Molecules

11 pages, 2646 KiB

Open AccessArticle

Inhibitory Activity of Quercetin 3-O-Arabinofuranoside and 2-Oxopomolic Acid Derived from Malus domestica on Soluble Epoxide Hydrolase

by In Sook Cho, Jang Hoon Kim, Yunjia Lin, Xiang Dong Su, Jong Seong Kang, Seo Young Yang and Young Ho Kim

Molecules 2020, 25(18), 4352; https://doi.org/10.3390/molecules25184352 - 22 Sep 2020

Cited by 9 | Viewed by 2820

Abstract

Flavonoids and triterpenoids were revealed to be the potential inhibitors on soluble epoxide hydrolase (sEH). The aim of this study is to reveal sEH inhibitors from Fuji apples. A flavonoid and three triterpenoids derived from the fruit of Malus domestica were identified as [...] Read more.

Flavonoids and triterpenoids were revealed to be the potential inhibitors on soluble epoxide hydrolase (sEH). The aim of this study is to reveal sEH inhibitors from Fuji apples. A flavonoid and three triterpenoids derived from the fruit of Malus domestica were identified as quercetin-3-O-arabinoside (1), ursolic acid (2), corosolic acid (3), and 2-oxopomolic acid (4). They had half-maximal inhibitory concentration of the inhibitors (IC₅₀) values of 39.3 ± 3.4, 84.5 ± 9.5, 51.3 ± 4.9, and 11.4 ± 2.7 μM, respectively, on sEH. The inhibitors bound to allosteric sites of enzymes in mixed (1) and noncompetitive modes (2–4). Molecular simulations were carried out for inhibitors 1 and 4 to calculate the binding force of ligands to receptors. The inhibitors bound to the left (1) and right (4) pockets next to the enzyme’s active site. Based on analyses of their molecular docking and dynamics, it was shown that inhibitors 1 and 4 can stably bind sEH at 1 bar and 300 K. Finally, inhibitors 1 and 4 are promising candidates for further studies using cell-based assays and in vivo cardiovascular tests. Full article

(This article belongs to the Special Issue Discovering New Natural Compounds with Pharmacological or Biotechnological Applications)

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Figure 1
The structures of compounds 1–4 isolated from the fruits of Malus domestica. Full article ">Figure 2
Inhibitory activities of the inhibitors 1–4 at a variety of concentrations toward soluble epoxide hydrolase (sEH) (A). Lineweaver-Burk plots (B–F) and Dixon plots (G–I) for the inhibition of sEH by compounds 1–4. Full article ">Figure 3
Predicted docking poses between compounds 1 and 4 and sEH (A,B). Hydrogen bonds of inhibitors 1 and 4 of the catalytic site, respectively (C,D). Full article ">Figure 4
Superpositions of sEH with compounds 1 and 4 for simulation trajectory (0 ns: red, 1: orange, 2: yellow, 3: green, 4: forest green, 5: cyan, 6: blue, 7: cornflower blue, 8: purple, 9: hot pink, and 10: magenta) (A,B). The potential energy (C), root mean square deviation (RMSD) (D), root mean square fluctuation (RMSF) (E), and hydrogen bonds (F,G) of the simulation calculated with 1 and 4 during 10 ns. Full article ">Figure 4 Cont.
Superpositions of sEH with compounds 1 and 4 for simulation trajectory (0 ns: red, 1: orange, 2: yellow, 3: green, 4: forest green, 5: cyan, 6: blue, 7: cornflower blue, 8: purple, 9: hot pink, and 10: magenta) (A,B). The potential energy (C), root mean square deviation (RMSD) (D), root mean square fluctuation (RMSF) (E), and hydrogen bonds (F,G) of the simulation calculated with 1 and 4 during 10 ns. Full article ">Figure 5
The Dictionary of Secondary Structure protein (DSSP) represented with secondary structure changes of sEH with inhibitor 1 (A) or 4 (B) (yellow square: Thr360-Pro371, black square: Ser415-Glu424, and blue square: Glu494-Pro501). Full article ">

13 pages, 979 KiB

Open AccessArticle

Oxazolochlorins 21. Most Efficient Access to meso-Tetraphenyl- and meso-Tetrakis(pentafluorophenyl)porpholactones, and Their Zinc(II) and Platinum(II) Complexes

by Damaris Thuita, Dinusha Damunupola and Christian Brückner

Molecules 2020, 25(18), 4351; https://doi.org/10.3390/molecules25184351 - 22 Sep 2020

Cited by 5 | Viewed by 3724

Abstract

meso-Phenyl- and meso-pentafluorophenyl-porpholactones, their metal complexes, as well as porphyrinoids directly derived from them are useful in a number of technical and biomedical applications, and more uses are expected to be discovered. About a dozen competing and complementary pathways toward their [...] Read more.

meso-Phenyl- and meso-pentafluorophenyl-porpholactones, their metal complexes, as well as porphyrinoids directly derived from them are useful in a number of technical and biomedical applications, and more uses are expected to be discovered. About a dozen competing and complementary pathways toward their synthesis were reported. The suitability of the methods changes with the meso-aryl group and whether the free base or metal derivatives are sought. These circumstances make it hard for anyone outside of the field of synthetic porphyrin chemistry to ascertain which pathway is the best to produce which specific derivative. We report here on what we experimentally evaluated to be the most efficient pathways to generate the six key compounds from the commercially available porphyrins, meso-tetraphenylporphyrin (TPP) and meso-tetrakis(pentafluorophenyl)porphyrin (T^FPP): free base meso-tetraphenylporpholactone (TPL) and meso-tetrakis(pentafluorophenyl)porpholactone (T^FPL), and their platinum(II) and zinc(II) complexes TPLPt, T^FPLPt, TPLZn, and T^FPLZn, respectively. Detailed procedures are provided to make these intriguing molecules more readily available for their further study. Full article

(This article belongs to the Special Issue Tetrapyrrolic Macrocycles: Synthesis, Functionalization and Applications 2020–2021)

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Graphical abstract

Graphical abstract
Full article ">Scheme 1
Generalized formation of meso-arylporpholactones from meso-arylporphyrins. Full article ">Scheme 2
Select literature-known reaction conditions toward the formation of meso-aryl(metallo)porpholactones. TPP = meso-tetraphenylporphyrin; TPPM = [meso-tetraphenylporphyrinato] metal complex; TFPP = meso-tetrakis(pentafluorophenyl)porphyrin; TFPPM = [meso-tetrakis(pentafluorophenyl)porphyrinato] metal complex; TPL = meso-tetraphenylporpholactone; TPPM = [meso-tetraphenylkporpholactonato] metal complex; TFPL = meso-tetrakis(pentafluorophenyl)porpholactone; TFPLM = [meso-tetrakis(pentafluorophenyl)porpholactonato] metal complex. Full article ">Scheme 3
The synthesis of meso-tetrakis(pentafluorophenyl)porpholactone (TFPL) and its zinc(II) (TFPLZn) and platinum(II) (TFPLPt) complexes. Full article ">Scheme 4
The most efficient synthesis of meso-tetraphenylporpholactone (TPL) and its zinc(II) (TPLZn) and platinum(II) (TPLPt) complexes. Full article ">

17 pages, 3907 KiB

Open AccessArticle

Comprehensive Evaluation of Metal Pollution in Urban Soils of a Post-Industrial City—A Case of Łódź, Poland

by Kinga Wieczorek, Anna Turek, Małgorzata Szczesio and Wojciech M. Wolf

Molecules 2020, 25(18), 4350; https://doi.org/10.3390/molecules25184350 - 22 Sep 2020

Cited by 22 | Viewed by 4873

Abstract

The pollution of urban soils by metals is a global problem. Prolonged exposure of habitants who are in contact with metals retained in soil poses a health risk. This particularly applies to industrialized cities with developed transport networks. The aim of the study [...] Read more.

The pollution of urban soils by metals is a global problem. Prolonged exposure of habitants who are in contact with metals retained in soil poses a health risk. This particularly applies to industrialized cities with developed transport networks. The aim of the study was to determine the content and spatial distribution of mobile metal fractions in soils of the city of Łódź and to identify their load and sources. Multivariate statistical analysis (principal component analysis (PCA), cluster analysis (CA)), combined with GIS, were used to make a comprehensive evaluation of the soil contamination. Hot-spots and differences between urban and suburban areas were also investigated. Metals were determined by atomic absorption spectrometry (AAS) after soil extraction with 1 mol L⁻¹ HCl. In most sites, the metal content changes in the following order: Zn > Pb > Cu > Ni > Cd. About one-third of the samples are considerably (or very highly) contaminated, (contamination factor, CF > 3) with Cu, Pb, or Zn. In almost 40% of the samples, contaminated soils were found (pollution load index, PLI > 1). All metals have a strong influence on the first principal component (PC1), whereas second principal component (PC2) is related to pH. Polluted soils are located in the downtown, in the south and east part of the city. The distribution of contamination coincides with the urban layout, low emission sources and former industrial areas of Łódź. Full article

(This article belongs to the Special Issue Determination of Trace Heavy Metals and Metalloids in Environmental Samples)

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24 pages, 516 KiB

Open AccessArticle

Volatile Profile Characterization of Croatian Commercial Sparkling Wines

by Ana-Marija Jagatić Korenika, Darko Preiner, Ivana Tomaz and Ana Jeromel

Molecules 2020, 25(18), 4349; https://doi.org/10.3390/molecules25184349 - 22 Sep 2020

Cited by 21 | Viewed by 4143

Abstract

Commercial sparkling wine production represents a relatively low but important part of the Croatian wine production, especially in the Zagreb county. This study presents the results of volatile aroma compounds profile and organic acid composition of commercial sparkling wine samples from three vine-growing [...] Read more.

Commercial sparkling wine production represents a relatively low but important part of the Croatian wine production, especially in the Zagreb county. This study presents the results of volatile aroma compounds profile and organic acid composition of commercial sparkling wine samples from three vine-growing regions in Zagreb county. In total, 174 volatile aroma compounds were identified, separated between their chemical classes (aldehydes, higher alcohols, volatile phenols, terpenes, C13-norisoprenoids, lactones, esters, fatty acids, sulfur compounds, other compounds, other alcohols). Higher alcohols such as phenylethyl and isoamyl alcohol as well as 2-methyl-1-butanol, and esters such as diethyl succinate, ethyl hydrogensuccinate, and ethyl lactate had the strongest impact on the volatile compounds profile of Zagreb county sparkling wine. The presence of diethyl glutarate and diethyl malonate, compounds whose concentrations are influenced by yeast autolysis or caused by chemical esterification during the ageing process, was also noted. The influence of every single volatile aroma compound was evaluated by discriminant analysis using forward stepwise model. The volatile profiles of traditional sparkling wines from Croatia were presented for the first time. It is hoped the results will contribute to better understanding the quality potential and to evaluate possible differences on the bases of detected aroma concentrations and multivariate analysis. Full article

(This article belongs to the Special Issue Wine Chemistry: The Key behind Wine Quality)

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13 pages, 3425 KiB

Open AccessArticle

Thymol Encapsulated into HP-β-Cyclodextrin as an Alternative to Synthetic Fungicides to Induce Lemon Resistance against Sour Rot Decay

by Vicente Serna-Escolano, María Serrano, Daniel Valero, María Isabel Rodríguez-López, José Antonio Gabaldón, Salvador Castillo, Juan Miguel Valverde, Pedro Javier Zapata, Fabián Guillén and Domingo Martínez-Romero

Molecules 2020, 25(18), 4348; https://doi.org/10.3390/molecules25184348 - 22 Sep 2020

Cited by 17 | Viewed by 2895

Abstract

Consumers demand the use of eco-friendly fungicides to treat fruit and vegetables and governmental authorities have unauthorized the application of chemical antifungals for the efficient control of sour rot. In the present research, the microwave irradiation (MW) method was used to encapsulate thymol [...] Read more.

Consumers demand the use of eco-friendly fungicides to treat fruit and vegetables and governmental authorities have unauthorized the application of chemical antifungals for the efficient control of sour rot. In the present research, the microwave irradiation (MW) method was used to encapsulate thymol into 2-hydroxylpropyl-beta-cyclodextrin (HP-β-CD) and the effect of these HP-β-CD on controlling sour rot in citrus fruit, caused by Geotrichum citri-aurantii, was evaluated. Amounts of 25 and 50 mM of HP-β-CD-thymol were used, and compared with propiconazole, to control the decay of inoculated lemon fruit. The treatments were performed in curative and preventive experiments. The incidence and severity of Geotrichum citri-aurantii in 25 and 50 mM HP-β-CD-thymol-treated fruit were reduced in both experiments. The preventive 50 mM HP-β-CD-thymol treatment showed the best effect, reducing the sour rot, respiration rate and fruit weight loss during storage at 20 °C. HP-β-CD-thymol increased polyphenol concentration and the activity of antioxidant enzymes, such as catalase (CAT), ascorbate peroxidase (APX) and peroxidase (POD) in lemon peel, and the highest effects were found with the 50-mM dose. In conclusion, the results show that the use of thymol encapsulated by MW into HP-β-CD could be an effective and sustainable tool, a substitute to the synthetic fungicides, for G. citri-auriantii control in citrus fruit. Full article

(This article belongs to the Special Issue Cyclodextrins: Recent Advances in Chemistry and Applications)

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Incidence (%) of fruit affected by G. citri-aurantii when 25 or 50 mM 2-hydroxylpropyl-beta-cyclodextrin (HP-β-CD)-thymol or propiconazole were applied as preventive (A) or curative (B) experiments. Severity (m2) of decayed lemons by G. citri-aurantii when 25 or 50 mM HP-β-CD-thymol or propiconazole were applied as preventive (C) or curative (D) experiments. Data are the mean ± SE. Different letters show significant differences (p < 0.05) among treatments for each sampling date. Full article ">Figure 2
Weight loss (%) of “Fino 49” lemon fruit treated with 25 or 50 mM HP-β-CD-thymol or propiconazole during 15 d of storage at 20 °C in preventive (A) and curative (B) experiments. Data are the mean ± SE. Different letters show significant differences (p < 0.05) among treatments, for each sampling date. Full article ">Figure 3
Weight loss (%) of “Fino 49” lemon fruit treated with 25 or 50 mM HP-β-CD-thymol or propiconazole during 15 d of storage at 20 °C in preventive (A) and curative (B) experiments. Data are the mean ± SE. Different letters show significant differences (p < 0.05) among treatments for each sampling date. Full article ">Figure 4
Total phenolics concentration (g kg−1 gallic acid equivalent), in peel of control, 25 or 50 mM of HP-β-CD-thymol or propiconazole treated “Fino 49” lemon fruits at harvest (day 0) and after 10 d of storage at 20 °C, in preventive experiment. Data are the mean ± SE. Different letters show significant differences (p < 0.05) among treatments after 10 days of storage. Full article ">Figure 5
Activity of the antioxidant enzymes catalase (CAT), ascorbate peroxidase (APX) and peroxidase (POD) and, in peel of control and 25 or 50 mM HP-β-CD-thymol and propiconazole treated “Fino 49” lemon fruit at harvest and after 10 d of storage at 20 °C in preventive experiment. Data are the mean ± SE. Different letters show significant differences (p < 0.05) among treatments after 10 days of storage. Full article ">

18 pages, 2359 KiB

Open AccessArticle

Development of an Optimized MALDI-TOF-MS Method for High-Throughput Identification of High-Molecular-Weight Glutenin Subunits in Wheat

by You-Ran Jang, Kyoungwon Cho, Se Won Kim, Susan B. Altenbach, Sun-Hyung Lim, Jae-Ryeong Sim and Jong-Yeol Lee

Molecules 2020, 25(18), 4347; https://doi.org/10.3390/molecules25184347 - 22 Sep 2020

Cited by 10 | Viewed by 3698

Abstract

Because high-molecular-weight glutenin subunits (HMW-GS) are important contributors to wheat end-use quality, there is a need for high-throughput identification of HMW-GS in wheat genetic resources and breeding lines. We developed an optimized method using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) to distinguish [...] Read more.

Because high-molecular-weight glutenin subunits (HMW-GS) are important contributors to wheat end-use quality, there is a need for high-throughput identification of HMW-GS in wheat genetic resources and breeding lines. We developed an optimized method using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) to distinguish individual HMW-GS by considering the effects of the alkylating reagent in protein extraction, solvent components, dissolving volume, and matrix II components. Using the optimized method, 18 of 22 HMW-GS were successfully identified in standard wheat cultivars by differences in molecular weights or by their associations with other tightly linked subunits. Interestingly, 1Bx7 subunits were divided into 1Bx7 group 1 and 1Bx7 group 2 proteins with molecular weights of about 82,400 and 83,000 Da, respectively. Cultivars containing the 1Bx7 group 2 proteins were distinguished from those containing 1Bx7^OE using well-known DNA markers. HMW-GS 1Ax2* and 1Bx6 and 1By8 and 1By8*, which are difficult to distinguish due to very similar molecular weights, were easily identified using RP-HPLC. To validate the method, HMW-GS from 38 Korean wheat varieties previously evaluated by SDS-PAGE combined with RP-HPLC were analyzed by MALDI-TOF-MS. The optimized MALDI-TOF-MS method will be a rapid, high-throughput tool for selecting lines containing desirable HMW-GS for breeding efforts. Full article

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Figure 1
Effects of four major factors on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) resolution of Chinese Spring using MALDI-TOF-MS. (A) treatment with alkylation reagent in glutenin extraction, (B) solvent components, (C) dilution volume, and (D) matrix II components. Parameters shown in red were found to be optimal and were incorporated into the new method. Full article ">Figure 2
HMW-GS profiles of standard wheat cultivars determined by MALDI-TOF-MS. Subunits corresponding to chromosomes 1A, 1B, and 1D are displayed in green, orange, and blue, respectively. Full article ">Figure 3
Amplification of DNA from standard cultivars containing 1Bx7 or 1Bx7OE genes. (A) PCR primers span the region of the 18 bp insertion in 1Bx7OE; (B) PCR primers from the left junction of the retroelement and duplicated region of Bx7OE; (C) PCR primers from right junction of the retroelement and duplicated region of Bx7OE. Glenlea and IT166460 were used as positive controls for Bx7OE. The 100 bp Plus DNA Ladder is shown in lanes (M). Full article ">Figure 4
Box and whisker plot of molecular weights of individual subunits in standard wheat cultivars. Red and blue boxes indicate subunits differing by less than 300 Da that were not distinguished by MALDI-TOF-MS, but could be differentiated by RP-HPLC. Full article ">Figure 5
RP-HPLC analysis of subunits that could not be distinguished by MALDI-TOF-MS. Subunits corresponding to chromosomes 1A, 1B, and 1D are displayed in green, orange, and blue, respectively. Unidentified subunits 1Ax2*, 1Bx6 and 1Bx8, and 1Bx8* are indicated with red arrows. Full article ">Figure 6
HMW-GS profiles of 38 Korean wheat cultivars of individual subunits determined by MALDI-TOF-MS. Subunits corresponding to chromosomes 1A, 1B, and 1D are shown in green, red, and blue, respectively. Full article ">

16 pages, 1907 KiB

Open AccessArticle

Structure and Performance of Benzoxazine Composites for Space Radiation Shielding

by Scott Winroth, Chris Scott and Hatsuo Ishida

Molecules 2020, 25(18), 4346; https://doi.org/10.3390/molecules25184346 - 22 Sep 2020

Cited by 22 | Viewed by 3829

Abstract

Innovative multifunctional materials that combine structural functionality with other spacecraft subsystem functions have been identified as a key enabling technology for future deep space missions. In this work, we report the structure and performance of multifunctional polymer matrix composites developed for aerospace applications [...] Read more.

Innovative multifunctional materials that combine structural functionality with other spacecraft subsystem functions have been identified as a key enabling technology for future deep space missions. In this work, we report the structure and performance of multifunctional polymer matrix composites developed for aerospace applications that require both structural functionality and space radiation shielding. Composites comprised of ultra-high molecular weight polyethylene (UHMWPE) fiber reinforcement and a hydrogen-rich polybenzoxazine matrix are prepared using a low-pressure vacuum bagging process. The polybenzoxazine matrix is derived from a novel benzoxazine resin that possesses a unique combination of attributes: high hydrogen concentration for shielding against galactic cosmic rays (GCR), low polymerization temperature to prevent damage to UHMWPE fibers during composite fabrication, long shelf-life, and low viscosity to improve flow during molding. Dynamic mechanical analysis (DMA) is used to study rheological and thermomechanical properties. Composite mechanical properties, obtained using several standardized tests, are reported. Improvement in composite stiffness, through the addition of carbon fiber skin layers, is investigated. Radiation shielding performance is evaluated using computer-based simulations. The composites demonstrate clear advantages over benchmark materials in terms of combined structural and radiation shielding performance. Full article

(This article belongs to the Special Issue Developing Polymers/Composites/Coatings for Space/Satellite Applications)

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11 pages, 2071 KiB

Open AccessArticle

Comparison of the Partial Structure and Antioxidant Activity of Polysaccharides from Two Species of Chinese Truffles

by Xiaolin Li, Zhongkai Zhu, Lei Ye, Zongjing Kang, Xiaoping Zhang, Yue Huang, Bo Zhang and Yuanfeng Zou

Molecules 2020, 25(18), 4345; https://doi.org/10.3390/molecules25184345 - 22 Sep 2020

Cited by 5 | Viewed by 2765

Abstract

Truffles are world-renowned premium commodities. Due to their unique aroma and rarity, the price of truffles has always been very high. In this study, Diethylaminoethyl anion exchange chromatography and gel filtration were employed for polysaccharide purification from two different species of Chinese truffles. [...] Read more.

Truffles are world-renowned premium commodities. Due to their unique aroma and rarity, the price of truffles has always been very high. In this study, Diethylaminoethyl anion exchange chromatography and gel filtration were employed for polysaccharide purification from two different species of Chinese truffles. Three polysaccharide fractions were obtained from Tuber panzhihuanense and referred to as TPZ-NP, TPZ-I, and TPZ-II. Additionally, two polysaccharide fractions were purified from T. pseudoexcavatum (TPD-NP and TPD-I). The results of structural elucidation indicated that the polysaccharide from different species showed different monosaccharide composition and linkage units, as well as molecular weight. Two of the polysaccharide fractions with the highest yield, TPZ-I and TPD-I, were chosen for biological testing. The results indicated that both fractions displayed antioxidant properties through mediation of the intestinal cellular antioxidant defense system, which could protect cultured intestinal cells from oxidative stress-induced damage and cell viability suppression. The TPD-I fraction showed stronger antioxidant effects, which may be due to the difference in structure. Further study on the structure-activity relationship is needed to be done. Full article

(This article belongs to the Special Issue Bioactive Compounds and Antioxidant Activity of Extracts from Different Natural Plants)

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Figure 1
The carbohydrate elution profiles monitored by the phenol-sulfuric acid assay. (A) Ion-exchange chromatography elution profile of crude polysaccharide from fruit bodies of T. panzhihuanense. (B) Ion-exchange chromatography elution profile of crude polysaccharide from fruit bodies of T. pseudoexcavatum. Full article ">Figure 2
The carbohydrate elution profiles of gel filtration chromatography, monitored with the phenol-sulfuric acid assay. Elution profiles of (A) TPZ-I, (B) TPZ-II, and (C) TPD-I. Full article ">Figure 3
Protective effects of TPZ-I and TPD-I on viability loss in porcine jejunum epithelial cells (IPEC-J2) induced by H2O2 (0.2 mM). The concentrations of polysaccharide fractions were 20, 10, and 5 μg/mL, respectively. Values are presented as means ± Standard error. Bars with different letters are statistically significant (p < 0.05). Full article ">Figure 4
Effects of TPZ-I and TPD-I on the activities of malondialdehyde-MDA (A), superoxide dismutase-SOD (B), catalase-CAT (C), and glutathione peroxidase-GSH-Px (D) in IPEC-J2 cells. The concentrations of the polysaccharide fractions were 20, 10, and 5 μg/mL, respectively. Values are presented as means ± SD (n = 6). Bars with different letters are statistically significant (p < 0.05). Full article ">Figure 5
Effects of TPZ-I and TPD-I on the activities of total antioxidant capacity-T-AOC (A), and reactive oxygen species-ROS (B) in IPEC-J2 cells. The concentrations of the polysaccharide fractions were 20, 10, and 5 μg/mL, respectively. Values are presented as means ± SD (n = 6). Bars with different letters are statistically significant (p < 0.05). Full article ">

18 pages, 2629 KiB

Open AccessArticle

Biocatalytic Potential of Native Basidiomycetes from Colombia for Flavour/Aroma Production

by David A. Jaramillo, María J. Méndez, Gabriela Vargas, Elena E. Stashenko, Aída-M. Vasco-Palacios, Andrés Ceballos and Nelson H. Caicedo

Molecules 2020, 25(18), 4344; https://doi.org/10.3390/molecules25184344 - 22 Sep 2020

Cited by 9 | Viewed by 4567

Abstract

Aromas and flavours can be produced from fungi by either de novo synthesis or biotransformation processes. Herein, the biocatalytic potential of seven basidiomycete species from Colombia fungal strains isolated as endophytes or basidioma was evaluated. Ganoderma webenarium, Ganoderma chocoense, and Ganoderma [...] Read more.

Aromas and flavours can be produced from fungi by either de novo synthesis or biotransformation processes. Herein, the biocatalytic potential of seven basidiomycete species from Colombia fungal strains isolated as endophytes or basidioma was evaluated. Ganoderma webenarium, Ganoderma chocoense, and Ganoderma stipitatum were the most potent strains capable of decolourizing β,β-carotene as evidence of their potential as biocatalysts for de novo aroma synthesis. Since a species’ biocatalytic potential cannot solely be determined via qualitative screening using β,β-carotene biotransformation processes, we focused on using α-pinene biotransformation with mycelium as a measure of catalytic potential. Here, two strains of Trametes elegans—namely, the endophytic (ET-06) and basidioma (EBB-046) strains—were screened. Herein, T. elegans is reported for the first time as a novel biocatalyst for the oxidation of α-pinene, with a product yield of 2.9 mg of cis-Verbenol per gram of dry weight mycelia used. The EBB-046 strain generated flavour compounds via the biotransformation of a Cape gooseberry medium and de novo synthesis in submerged cultures. Three aroma-producing compounds were identified via GC–MS—namely, methyl-3-methoxy-4H-pyran-4-one, hexahydro-3-(methylpropyl)-pyrrolo[1,2-a]pyrazine-1,4-dione, and hexahydro-3-(methylphenyl)-pyrrolo[1,2-a]pyrazine-1,4-dione. Full article

(This article belongs to the Special Issue Natural Products from Fungi)

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Full article ">Figure 1
β,β-carotene biotransformation after a 4- and 14-day incubation periods. Screening was conducted using seven strains of native basidiomycetes—namely, Ganoderma stipitatum (A), Ganoderma chocoense (B), Ganoderma gibbosum (C), Ganoderma weberianum (D), Laetiporus gilbertsonii (E), Trametes elegans (endophyte) (F), and Trametes elegans (G). Full article ">Figure 2
The hydroxylation of α-pinene via the P450 monooxygenase/reductase system (adapted from Krings [<a href="#B57-molecules-25-04344" class="html-bibr">57</a>]). Full article ">Figure 3
The influence exerted by the concentration of α-pinene (10 and 20 mM) and the mycelium (5 and 10 g/L) on the cis-Verbenol yield during biotransformation reactions using whole cells of the EBB-046 and ET-06 strains of Trametes elegans. The incubation time was 48 h. Full article ">Figure 4
(A) Pellets formed by the EBB-046 strain in the Yeast extract-Malt extract medium YM. (B) Mycelial clumps formed by the EBB-046 strain in the yeast extract medium. (C) Image of the submerged culture of Trametes elegans (EBB-046 strain) in a defined medium using Cape Gooseberry after an incubation period of 96 h. Full article ">Figure 5
Intensity progress descriptor for the generation of sweet and fruity odours as a function of time by Trametes elegans mycelia cultivated in media containing Cape Gooseberry. The odour intensity was rated on a scale of one to eight, where 1–2 represented a low intensity, 3–4 was described as “characteristic”, 5–6 was classified as “intense”, and 7–8 was a strong odour. Full article ">Figure 6
Chromatogram of the biotransformation products of Trametes elegans (EBB-046) obtained after an 80-h incubation period. Full article ">

21 pages, 906 KiB

Open AccessReview

The Lipidome Fingerprint of Longevity

by Mariona Jové, Natàlia Mota-Martorell, Irene Pradas, José Daniel Galo-Licona, Meritxell Martín-Gari, Èlia Obis, Joaquim Sol and Reinald Pamplona

Molecules 2020, 25(18), 4343; https://doi.org/10.3390/molecules25184343 - 22 Sep 2020

Cited by 19 | Viewed by 4295

Abstract

Lipids were determinants in the appearance and evolution of life. Recent studies disclose the existence of a link between lipids and animal longevity. Findings from both comparative studies and genetics and nutritional interventions in invertebrates, vertebrates, and exceptionally long-lived animal species—humans included—demonstrate that [...] Read more.

Lipids were determinants in the appearance and evolution of life. Recent studies disclose the existence of a link between lipids and animal longevity. Findings from both comparative studies and genetics and nutritional interventions in invertebrates, vertebrates, and exceptionally long-lived animal species—humans included—demonstrate that both the cell membrane fatty acid profile and lipidome are a species-specific optimized evolutionary adaptation and traits associated with longevity. All these emerging observations point to lipids as a key target to study the molecular mechanisms underlying differences in longevity and suggest the existence of a lipidome profile of long life. Full article

(This article belongs to the Special Issue Lipids in Health and Disease)

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17 pages, 2249 KiB

Open AccessArticle

Design, Synthesis, In Vitro and In Silico Studies of New Thiazolylhydrazine-Piperazine Derivatives as Selective MAO-A Inhibitors

by Begüm Nurpelin Sağlık, Osman Cebeci, Ulviye Acar Çevik, Derya Osmaniye, Serkan Levent, Betül Kaya Çavuşoğlu, Sinem Ilgın, Yusuf Özkay and Zafer Asım Kaplancıklı

Molecules 2020, 25(18), 4342; https://doi.org/10.3390/molecules25184342 - 22 Sep 2020

Cited by 9 | Viewed by 2853

Abstract

Monoamine oxidase (MAO) isoenzymes are very important drug targets among neurological disorders. Herein, novel series of thiazolylhydrazine-piperazine derivatives were designed, synthesized and evaluated for their MAO-A and -B inhibitory activity. The structures of the synthesized compounds were assigned using different spectroscopic techniques such [...] Read more.

Monoamine oxidase (MAO) isoenzymes are very important drug targets among neurological disorders. Herein, novel series of thiazolylhydrazine-piperazine derivatives were designed, synthesized and evaluated for their MAO-A and -B inhibitory activity. The structures of the synthesized compounds were assigned using different spectroscopic techniques such as ¹H-NMR, ¹³C-NMR and HRMS. Moreover, the prediction of ADME (Absorption, Distribution, Metabolism, Elimination) parameters for all of the compounds were performed using in silico method. According to the enzyme inhibition results, the synthesized compounds showed the selectivity against MAO-A enzyme inhibition. Compounds 3c, 3d and 3e displayed significant MAO-A inhibition potencies. Among them, compound 3e was found to be the most effective derivative with an IC₅₀ value of 0.057 ± 0.002 µM. Moreover, it was seen that this compound has a more potent inhibition profile than the reference inhibitors moclobemide (IC₅₀ = 6.061 ± 0.262 µM) and clorgiline (IC₅₀ = 0.062 ± 0.002 µM). In addition, the enzyme kinetics were performed for compound 3e and it was determined that this compound had a competitive and reversible inhibition type. Molecular modeling studies aided in the understanding of the interaction modes between this compound and MAO-A. It was found that compound 3e had significant and important binding property. Full article

(This article belongs to the Special Issue Trends in the Development of Enzyme Inhibitors)

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Design of target compounds. Full article ">Figure 2
(A) Lineweaver-Burk plots for the inhibition of MAO-A by compound 3e. [S], substrate concentration (µM); V, reaction velocity (nmol/min/mg protein). Inhibitor concentrations are shown at the left. (B) Secondary plot (slope, namely Km/Vmax obtained from graph A, versus inhibitor concentrations) of compound 3e for determining the steady-state inhibition constant (Ki). Ki was calculated to be 0.011 μM. Full article ">Figure 3
The three-dimensional (3D) poses of compounds 3c, 3d and 3e in the active region of MAO-A (PDB ID: 2Z5X). The compounds are shown in a tube pattern and are yellow, maroon and orange colored, respectively. Full article ">Figure 4
The 3D interacting modes of compound 3c, 3d and 3e in the active region of MAO-A. Tube model introduce the ligands and the relevant residues in the enzyme’s active site. The flavin adenine dinucleotide (FAD) molecule is shown in a ball and stick pattern and is blue colored. (A) Compound 3c is colored = yellow. (B) Compound 3d is colored maroon. (C) Compound 3e is colored orange. Full article ">Scheme 1
The synthetic route of the compounds (3a–3l). Reagents and conditions: (i) DMF, K2CO3, reflux, 24 h; (ii) EtOH, reflux, 3 h; (iii) EtOH, reflux, 4–8 h. Full article ">

22 pages, 5067 KiB

Open AccessArticle

Novel Bis-Ammonium Salts of Pyridoxine: Synthesis and Antimicrobial Properties

by Nikita V. Shtyrlin, Mikhail V. Pugachev, Sergey V. Sapozhnikov, Marsel R. Garipov, Rusalia M. Vafina, Denis Y. Grishaev, Roman S. Pavelyev, Renata R. Kazakova, Mariya N. Agafonova, Alfiya G. Iksanova, Svetlana A. Lisovskaya, Marina I. Zeldi, Elena S. Krylova, Elena V. Nikitina, Alina E. Sabirova, Airat R. Kayumov and Yurii G. Shtyrlin

Molecules 2020, 25(18), 4341; https://doi.org/10.3390/molecules25184341 - 22 Sep 2020

Cited by 16 | Viewed by 3371

Abstract

A series of 108 novel quaternary bis-ammonium pyridoxine derivatives carrying various substituents at the quaternary nitrogen’s and acetal carbon was synthesized. Thirteen compounds exhibited antibacterial and antifungal activity (minimum inhibitory concentration (MIC) 0.25–16 µg/mL) comparable or superior than miramistin, benzalkonium chloride, and chlorhexidine. [...] Read more.

A series of 108 novel quaternary bis-ammonium pyridoxine derivatives carrying various substituents at the quaternary nitrogen’s and acetal carbon was synthesized. Thirteen compounds exhibited antibacterial and antifungal activity (minimum inhibitory concentration (MIC) 0.25–16 µg/mL) comparable or superior than miramistin, benzalkonium chloride, and chlorhexidine. A strong correlation between the lipophilicity and antibacterial activity was found. The most active compounds had logP values in the range of 1–3, while compounds with logP > 6 and logP < 0 were almost inactive. All active compounds demonstrated cytotoxicity comparable with miramistin and chlorhexidine on HEK-293 cells and were three-fold less toxic when compared to benzalkonium chloride. The antibacterial activity of leading compound 5c₁₂ on biofilm-embedded Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli or Pseudomonas aeruginosa was comparable or even higher than that of the benzalkonium chloride. In vivo 5c₁₂ was considerably less toxic (LD₅₀ 1705 mg/kg) than benzalkonium chloride, miramistine, and chlorhexidine at oral administration on CD-1 mice. An aqueous solution of 5c₁₂ (0.2%) was shown to be comparable to reference drugs efficiency on the rat’s skin model. The molecular target of 5c₁₂ seems to be a cellular membrane as other quaternary ammonium salts. The obtained results make the described quaternary bis-ammonium pyridoxine derivatives promising and lead molecules in the development of the new antiseptics with a broad spectrum of antimicrobial activity. Full article

(This article belongs to the Special Issue Microbiocides Chemistry)

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Graphical abstract

Graphical abstract
Full article ">Figure 1
The structures of QAC based on pyridoxine derivatives obtained by us earlier [<a href="#B13-molecules-25-04341" class="html-bibr">13</a>,<a href="#B14-molecules-25-04341" class="html-bibr">14</a>,<a href="#B15-molecules-25-04341" class="html-bibr">15</a>,<a href="#B16-molecules-25-04341" class="html-bibr">16</a>,<a href="#B17-molecules-25-04341" class="html-bibr">17</a>,<a href="#B18-molecules-25-04341" class="html-bibr">18</a>,<a href="#B19-molecules-25-04341" class="html-bibr">19</a>] and compounds 5a8–5r18 synthesized in this work. Full article ">Figure 2
Lg1/MIC versus calculated logP relationship for novel bis-ammonium salts of pyridoxine. The parabolic line shows the polynomial approximation by using a second order model. Inactive compounds (MIC > 64 mg/mL) are not shown. Full article ">Figure 3
The effect of 5c12 and reference antiseptics on biofilm-embedded bacteria. (A)—S. aureus; (B)—S. intermedius; (C)—E. coli, (D)—P. aeruginosa. The 48-h biofilms were treated with 1–16 × MBCs of benzalkonium chloride (circles), miramistin (squares), or 5c12 (triangles) for 24 h and then quantified by CFU counting. Data are present as medians from five independent experiments with interquartile range (M ± IQR). Dotted line shows 3 log-decrease of viable cells. Full article ">Figure 4
In vivo antibacterial efficacy test (Mean ± SD) using a rat skin model. log10 number of viable cells in the control and the number of viable cells after exposure with 5c12, miramistin, benzalkonium chloride, and chlorhexidine, n = 6. Full article ">Figure 5
The effect of 5c12 on the electric potential of the bacterial membrane determined using a membrane-potential-sensitive cyanine dye DiSC3(5) (10 min treatment by 1–8 × MBC (A,B) and 20 min treatment by 1–8 × MBC (C,D)). Asterisks denote a statistically significant difference in comparison with untreated cells. * statistically significant difference from the control. Full article ">Figure 6
Scanning Electron Microscopy microphotographs of S. aureus ATCC209p (A,C) and E. coli CDC F-50 (B,D). Untreated cells (A,B) and bacteria treated by 0.2% solution of 5c12 for 30 min (C,D). 50,000× magnification. Full article ">Scheme 1
Reagents and conditions. (i) R1C(O)R2, HCl, 3–5 °C, 3 h; or C6H6, R1C(O)R2, p-TsOH, reflux, 17 h, (ii) H2O, NaOH, 20 °C, (iii) CH2Cl2, SOCl2, 20 °C, 17 h, (iv) H2O/CHCl3, NaHCO3, (v) CHCl3, TCICA, reflux, 4 h, (vi) C2H5OH, R3N(CH3)2, 70 °C, 5 h. Full article ">

19 pages, 1416 KiB

Open AccessArticle

Urinary Resveratrol Metabolites Output: Differential Associations with Cardiometabolic Markers and Liver Enzymes in House-Dwelling Subjects Featuring Metabolic Syndrome

by Vanessa Bullón-Vela, Itziar Abete, Maria Angeles Zulet, Yifan Xu, Miguel A. Martínez-González, Carmen Sayón-Orea, Miguel Ruiz-Canela, Estefanía Toledo, Vicente Martín Sánchez, Ramon Estruch, Rosa María Lamuela-Raventós, Enrique Almanza-Aguilera, Montserrat Fitó, Jordi Salas-Salvadó, Andrés Díaz-López, Francisco J. Tinahones, Josep A. Tur, Dora Romaguera, Jadwiga Konieczna, Xavier Pintó, Lidia Daimiel, Ana Rodriguez-Mateos and José Alfredo Martínez Show full author list Hide full author list

Molecules 2020, 25(18), 4340; https://doi.org/10.3390/molecules25184340 - 22 Sep 2020

Cited by 7 | Viewed by 3615

Abstract

Metabolic syndrome (MetS) components are strongly associated with increased risk of non-alcoholic fatty liver disease (NAFLD) development. Several studies have supported that resveratrol is associated with anti-inflammatory and antioxidant effects on health status. The main objective of this study was to assess the [...] Read more.

Metabolic syndrome (MetS) components are strongly associated with increased risk of non-alcoholic fatty liver disease (NAFLD) development. Several studies have supported that resveratrol is associated with anti-inflammatory and antioxidant effects on health status. The main objective of this study was to assess the putative associations between some urinary resveratrol phase II metabolites, cardiometabolic, and liver markers in individuals diagnosed with MetS. In this cross-sectional study, 266 participants from PREDIMED Plus study (PREvención con DIeta MEDiterránea) were divided into tertiles of total urinary resveratrol phase II metabolites (sum of five resveratrol conjugation metabolites). Urinary resveratrol metabolites were analyzed by ultra- performance liquid chromatography coupled to triple quadrupole mass spectrometry (UPLC-Q-q-Q MS), followed by micro-solid phase extraction (µ-SPE) method. Liver function markers were assessed using serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyl transferase (GGT). Moreover, lipid profile was measured by triglycerides, very-low-density lipoprotein cholesterol (VLDL-c), and total cholesterol/high-density lipoprotein ratio (total cholesterol/HDL). Linear regression adjusted models showed that participants with higher total urine resveratrol concentrations exhibited improved lipid and liver markers compared to the lowest tertile. For lipid determinations: log triglycerides (β_T3= −0.15, 95% CI; −0.28, −0.02, p-trend = 0.030), VLDL-c, (β_T3= −4.21, 95% CI; −7.97, −0.46, p-trend = 0.039), total cholesterol/HDL ratio Moreover, (β_T3= −0.35, 95% CI; −0.66, −0.03, p-trend = 0.241). For liver enzymes: log AST (β_T3= −0.12, 95% CI; −0.22, −0.02, p-trend = 0.011, and log GGT (β_T3= −0.24, 95% CI; −0.42, −0.06, p-trend = 0.002). However, there is no difference found on glucose variables between groups. To investigate the risk of elevated serum liver markers, flexible regression models indicated that total urine resveratrol metabolites were associated with a lower risk of higher ALT (169.2 to 1314.3 nmol/g creatinine), AST (599.9 to 893.8 nmol/g creatinine), and GGT levels (169.2 to 893.8 nmol/g creatinine). These results suggested that higher urinary concentrations of some resveratrol metabolites might be associated with better lipid profile and hepatic serum enzymes. Moreover, urinary resveratrol excreted showed a reduced odds ratio for higher liver enzymes, which are linked to NAFLD. Full article

(This article belongs to the Section Natural Products Chemistry)

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8 pages, 1791 KiB

Open AccessArticle

Conformation of G-quadruplex Controlled by Click Reaction

by Chao-Da Xiao, Zhi-Yong He, Chuan-Xin Guo, Xiang-Chun Shen and Yan Xu

Molecules 2020, 25(18), 4339; https://doi.org/10.3390/molecules25184339 - 22 Sep 2020

Cited by 1 | Viewed by 2905

Abstract

G-quadruplexes are non-canonical four stranded secondary structures possessing great biological importance. Controlling G-quadruplex conformation for further regulating biological processes is both exciting and challenging. In this study, we described a method for regulating G-quadruplex conformation by click chemistry for the first time. 8-ethynyl-2′-deoxyguanosine [...] Read more.

G-quadruplexes are non-canonical four stranded secondary structures possessing great biological importance. Controlling G-quadruplex conformation for further regulating biological processes is both exciting and challenging. In this study, we described a method for regulating G-quadruplex conformation by click chemistry for the first time. 8-ethynyl-2′-deoxyguanosine was synthesized and incorporated into a 12-nt telomere DNA sequence. Such a sequence, at first, formed mixed parallel/anti-parallel G-quadruplexes, while it changed to anti-parallel after reaction with azidobenzene. Meanwhile, the click reaction can give the sequence intense fluorescence. Full article

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Figure 1
(a) Click reaction controls the glycosidic conformation of modified guanine nucleoside. (b) G-quadruplex topology changed by manipulating the glycosidic conformation of modified guanine nucleoside through click reaction. Full article ">Figure 2
(a) NOESY spectrum of 8etdG click reaction product. Cross peak between H in the triazole ring and H1′ is in the red box. (b) Schematic representation of syn glycosidic conformation of 8etdG click reaction product with arrows indicating the NOEs. Full article ">Figure 3
HPLC analyses of the ODN-N reaction with the CuAAC reaction solution at the indicted time where peak “P” is the product. Full article ">Figure 4
(a) CD spectrum of unreacted and click reaction product of ODN-9. (b) Fluorescence spectra for modified oligonucleotides. ODN-9 P (em): the emission spectrum for click reaction product of ODN-9; ODN-9 (em): emission spectrum for the ODN-9 unreacted sequence; ODN-9 P (ex), excitation spectrum (345 nm). Full article ">Scheme 1
Reagents and conditions: (a) Trimethylsilyl acetylene, Tetrakis(triphenylphosphine)palladium, Triethylamine, N,N-Dimethylformamide, 50 °C, 3 h; (b) Tetrabutylammonium fluoride, Tetrahydrofuran, rt, 2 h; (c) N,N-dimethylformamide diethylacetal, methanol, 55 °C, 3 h; (d) 4,4′-Dimethoxytriphenylmethyl chloride, Triethylamine, 4-(Dimethylamino)pyridine, Pyridine, rt, overnight; (e) N,N-diisopropylchlorophosphoramidite, Triethylamine, rt, 15 min. Full article ">

16 pages, 430 KiB

Open AccessReview

Autophagy, One of the Main Steps in Periodontitis Pathogenesis and Evolution

by Maria Greabu, Francesca Giampieri, Marina Melescanu Imre, Maria Mohora, Alexandra Totan, Silviu Mirel Pituru and Ecaterina Ionescu

Molecules 2020, 25(18), 4338; https://doi.org/10.3390/molecules25184338 - 22 Sep 2020

Cited by 29 | Viewed by 3968

Abstract

Periodontitis represents a complex inflammatory disease that compromises the integrity of the tooth-supporting tissue through the interaction of specific periodontal pathogens and the host’s immune system. Experimental data help to outline the idea that the molecular way towards periodontitis initiation and progression presents [...] Read more.

Periodontitis represents a complex inflammatory disease that compromises the integrity of the tooth-supporting tissue through the interaction of specific periodontal pathogens and the host’s immune system. Experimental data help to outline the idea that the molecular way towards periodontitis initiation and progression presents four key steps: bacterial infection, inflammation, oxidative stress, and autophagy. The aim of this review is to outline the autophagy involvement in the pathogenesis and evolution of periodontitis from at least three points of view: periodontal pathogen invasion control, innate immune signaling pathways regulation and apoptosis inhibition in periodontal cells. The exact roles played by reactive oxygen species (ROS) inside the molecular mechanisms for autophagy initiation in periodontitis still require further investigation. However, clarifying the role and the mechanism of redox regulation of autophagy in the periodontitis context may be particularly beneficial for the elaboration of new therapeutic strategies. Full article

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23 pages, 8091 KiB

Open AccessArticle

Sulphamoylated Estradiol Analogue Induces Reactive Oxygen Species Generation to Exert Its Antiproliferative Activity in Breast Cancer Cell Lines

by Maphuti T. Lebelo, Anna M. Joubert and Michelle H. Visagie

Molecules 2020, 25(18), 4337; https://doi.org/10.3390/molecules25184337 - 22 Sep 2020

Cited by 4 | Viewed by 2521

Abstract

2-Methoxyestradiol (2ME), a 17β-estradiol metabolite, exerts anticancer properties in vitro and in vivo. To address 2ME’s low bioavailability, research led to the in silico design of sulphamoylated 2ME analogues. However, the role of oxidative stress induced in the activity exerted by sulphamoylated compounds [...] Read more.

2-Methoxyestradiol (2ME), a 17β-estradiol metabolite, exerts anticancer properties in vitro and in vivo. To address 2ME’s low bioavailability, research led to the in silico design of sulphamoylated 2ME analogues. However, the role of oxidative stress induced in the activity exerted by sulphamoylated compounds remains elusive. In the current study, the influence of 2-Ethyl-17-oxoestra-1,3,5(10)-trien-3-yl sulphamate (ESE-one) on reactive oxygen species (ROS) induction and its effect on cell proliferation, as well as morphology, were assessed in breast tumorigenic cells (MCF-7 and MDA-MB-231). Fluorescent microscopy showed that sulphamoylated estradiol analogues induced hydrogen peroxide and superoxide anion, correlating with decreased cell growth demonstrated by spectrophotometry data. ESE-one exposure resulted in antiproliferation which was repressed by tiron (superoxide inhibitor), trolox (peroxyl inhibitor) and N,N′-dimethylthiourea (DMTU) (hydrogen peroxide inhibitor). Morphological studies demonstrated that tiron, trolox and DMTU significantly decreased the number of rounded cells and shrunken cells in MCF-7 and MDA-MB-231 cells induced by ESE-one. This in vitro study suggests that ESE-one induces growth inhibition and cell rounding by production of superoxide anion, peroxyl radical and hydrogen peroxide. Identification of these biological changes in cancer cells caused by sulphamoylated compounds hugely contributes towards improvement of anticancer strategies and the ROS-dependent cell death pathways in tumorigenic breast cells. Full article

(This article belongs to the Special Issue From Cell Signalling to Anticancer Drug Discovery: A Theme Issue in Honor of Professor Barry Potter)

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14 pages, 579 KiB

Open AccessArticle

Antioxidant Extracts of Three Russula Genus Species Express Diverse Biological Activity

by Marina Kostić, Marija Ivanov, Ângela Fernandes, José Pinela, Ricardo C. Calhelha, Jasmina Glamočlija, Lillian Barros, Isabel C. F. R. Ferreira, Marina Soković and Ana Ćirić

Molecules 2020, 25(18), 4336; https://doi.org/10.3390/molecules25184336 - 22 Sep 2020

Cited by 19 | Viewed by 4439

Abstract

This study explored the biological properties of three wild growing Russula species (R. integra, R. rosea, R. nigricans) from Serbia. Compositional features and antioxidant, antibacterial, antibiofilm, and cytotoxic activities were analyzed. The studied mushroom species were identified as being [...] Read more.

This study explored the biological properties of three wild growing Russula species (R. integra, R. rosea, R. nigricans) from Serbia. Compositional features and antioxidant, antibacterial, antibiofilm, and cytotoxic activities were analyzed. The studied mushroom species were identified as being rich sources of carbohydrates and of low caloric value. Mannitol was the most abundant free sugar and quinic and malic acids the major organic acids detected. The four tocopherol isoforms were found, and polyunsaturated fatty acids were the predominant fat constituents. Regarding phenolic compounds, P-hydroxybenzoic and cinnamic acids were identified in the prepared methanolic and ethanolic extracts, which displayed antioxidant activity through the inhibition of thiobarbituric acid reactive substances (TBARS) formation and oxidative hemolysis; the highest activity was attributed to the R. nigricans ethanolic extract. This is the first report on the antibacterial and antibiofilm potential of the studied species, with the most promising activity observed towards Streptococcus spp. (0.20–0.78 mg/mL as the minimal inhibitory concentration, MIC). The most promising cytotoxic effect was caused by the R. integra methanolic extract on non-small cell lung cancer cells (NCI-H460). Therefore, due to the observed in vitro bioactive properties, the studied mushrooms arise as a source of functional ingredients with potential to be used in novel nutraceutical and drug formulations, which can be used in the treatment of various diseases and health conditions. Full article

(This article belongs to the Special Issue Measurement of Antioxidant Activity: Advances and Perspectives)

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9 pages, 1117 KiB

Open AccessArticle

Isolation and FTIR-ATR and ¹H NMR Characterization of Alginates from the Main Alginophyte Species of the Atlantic Coast of Morocco

by Zahira Belattmania, Soukaina Kaidi, Samir El Atouani, Chaimaa Katif, Fouad Bentiss, Charafeddine Jama, Abdeltif Reani, Brahim Sabour and Vitor Vasconcelos

Molecules 2020, 25(18), 4335; https://doi.org/10.3390/molecules25184335 - 22 Sep 2020

Cited by 60 | Viewed by 5950

Abstract

Alginates are widely used as gelling agents in textile print pastes, medical industries, impression material in dentistry, and anticoagulant material in toothpaste. In the present study, the content and spectroscopic characterization (¹H NMR and FT-IR) of the sodium alginates were investigated [...] Read more.

Alginates are widely used as gelling agents in textile print pastes, medical industries, impression material in dentistry, and anticoagulant material in toothpaste. In the present study, the content and spectroscopic characterization (¹H NMR and FT-IR) of the sodium alginates were investigated in the eight brown seaweeds Sargassum muticum, Fucus vesiculosus f. volubilis, Carpodesmia tamariscifolia, Bifurcaria bifurcata, Laminaria ochroleuca, Cystoseira humilis, Saccorhiza polyschides, and Fucus guiryi harvested from the NW Atlantic coast of Morocco. The results proved that the most studied algae depicted alginate yields higher than 18% dry weight. The FT-IR analysis showed that the spectra of the extracted alginates exhibited significant similarities to the commercial alginate from Sigma-Aldrich. The ¹H NMR spectroscopy indicated that the extracted alginates have a high content of β-d-mannuronic (M) than α-l-guluronic acid (G) with M/G ratio values ranging from 1.04 to 4.41. The homopolymeric fractions F_MM are remarkably high compared to the F_GG and heteropolymeric fractions (F_GM = F_MG) especially for F. guiryi, C humilis, C. tamariscifolia, L. ochroleuca, and S. polyschides. Nevertheless, the heteropolymeric fractions (F_GM/F_MG) are quite abundant in the alginates of S. muticum, F. vesiculosus f. volubilis, and B. bifurcata accounting for more than 52% of the polymer diads. Based on these results, the investigated algal species (except Fucus guiryi and Bifurcaria bifurcata) could be regarded as potential sources of alginates for industrial uses. Full article

(This article belongs to the Special Issue Bioactive Compounds with Applications in Health and Food)

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14 pages, 5105 KiB

Open AccessArticle

N-Benzyl Residues as the P1′ Substituents in Phosphorus-Containing Extended Transition State Analog Inhibitors of Metalloaminopeptidases

by Kamila Janiszewska, Michał Talma, Bartosz Oszywa, Małgorzata Pawełczak, Paweł Kafarski and Artur Mucha

Molecules 2020, 25(18), 4334; https://doi.org/10.3390/molecules25184334 - 22 Sep 2020

Cited by 1 | Viewed by 2686

Abstract

Peptidyl enzyme inhibitors containing an internal aminomethylphosphinic bond system (P(O)(OH)-CH₂-NH) can be termed extended transition state analogs by similarity to the corresponding phosphonamidates (P(O)(OH)-NH). Phosphonamidate pseudopeptides are broadly recognized as competitive mechanism-based inhibitors of metalloenzymes, mainly hydrolases. Their practical use is, [...] Read more.

Peptidyl enzyme inhibitors containing an internal aminomethylphosphinic bond system (P(O)(OH)-CH₂-NH) can be termed extended transition state analogs by similarity to the corresponding phosphonamidates (P(O)(OH)-NH). Phosphonamidate pseudopeptides are broadly recognized as competitive mechanism-based inhibitors of metalloenzymes, mainly hydrolases. Their practical use is, however, limited by hydrolytic instability, which is particularly restricting for dipeptide analogs. Extension of phosphonamidates by addition of the methylene group produces a P-C-N system fully resistant in water conditions. In the current work, we present a versatile synthetic approach to such modified dipeptides, based on the three-component phospha-Mannich condensation of phosphinic acids, formaldehyde, and N-benzylglycines. The last-mentioned component allowed for simple and versatile introduction of functionalized P1′ residues located on the tertiary amino group. The products demonstrated moderate inhibitory activity towards porcine and plant metalloaminopeptidases, while selected derivatives appeared very potent with human alanyl aminopeptidase (K_i = 102 nM for 6a). Analysis of ligand-protein complexes obtained by molecular modelling revealed canonical modes of interactions for mono-metallic alanyl aminopeptidases, and distorted modes for di-metallic leucine aminopeptidases (with C-terminal carboxylate, not phosphinate, involved in metal coordination). In general, the method can be dedicated to examine P1′-S1′ complementarity in searching for non-evident structures of specific residues as the key fragments of perspective ligands. Full article

(This article belongs to the Special Issue Recent Developments in the Synthesis and Utilization of Organophosphorus Compounds)

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Graphical abstract

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Full article ">Figure 1
General formula of pseudodipeptides containing an internal aminomethylphosphinate bond system planned for the synthesis. Selected heteroatom-modified/functionalized benzyl P1′ residues are envisaged to be installed as the N-substituents. The activities of the unsubstituted derivative 1 reported previously for porcine enzymes are considered as the reference [<a href="#B7-molecules-25-04334" class="html-bibr">7</a>]. Full article ">Figure 2
Modeled conformations of N-benzyloxycarbonyl-protected 4-Br derivative 4b, with energies minimized for each stereoisomer. (a) trans-carbamate/(R), ΔG = −266.9 kJ/mol; (b) trans-carbamate/(S), ΔG = −280.8 kJ/mol; (c) cis-carbamate/(R), ΔG = −258.1 kJ/mol; (d) cis-carbamate/(S), ΔG = −269.2 kJ/mol. Full article ">Figure 3
Modeled binding mode of the (R) (a) and (S) enantiomer (b) of phosphinic dipeptide analog 6b containing a 4-bromobenzyl P1′ fragment in the active center of porcine aminopeptidase N (PDB: 4FKE) [<a href="#B23-molecules-25-04334" class="html-bibr">23</a>]. Amino acid residues of the inhibitor and enzyme are shown as sticks, while the zinc ion is shown as a gray sphere. Hydrogen bonds and nonpolar interactions are shown as thin dashed lines. Full article ">Figure 4
Modeled binding mode of (R) enantiomer of phosphinic dipeptide analog 6b containing a 4-bromobenzyl P1′ fragment in the active center of human aminopeptidase N (PDB: 4FYT) [<a href="#B24-molecules-25-04334" class="html-bibr">24</a>]. Amino acid residues of the inhibitor and enzyme are shown as sticks, while the zinc ion is shown as a gray sphere. Hydrogen bonds and nonpolar interactions are shown as thin dashed lines, while the surface of the active site is colored according to hydrophobicity. Full article ">Figure 5
Modeled binding mode of phosphinic dipeptide analog (R)-6c containing a 4-carboxybenzyl P1′ fragment in the active center of bovine leucine aminopeptidase (PDB: 1LAM) [<a href="#B25-molecules-25-04334" class="html-bibr">25</a>]. Amino acid residues of the inhibitor and enzyme are shown as sticks, while zinc ions are shown as gray spheres. Hydrogen bonds and nonpolar interactions are shown as thin dashed lines. Full article ">Figure 6
Modeled binding mode of phosphinic dipeptide analog (R)-6d containing a 4-nitrobenzyl P1′ fragment in the active center of tomato leucine aminopeptidase (PDB: 4KSI) [<a href="#B26-molecules-25-04334" class="html-bibr">26</a>]. Amino acid residues of the inhibitor and enzyme are shown as sticks, while magnesium ions are shown as green spheres. Hydrogen bonds and nonpolar interactions are shown as thin dashed lines. Full article ">Scheme 1
The synthesis of pseudodipeptides containing the aminomethylphosphinic bond system. Reagents and conditions: (a) KOH, NaBH4, EtOH, 15 °C, 24 h; (b) pH 4–5; (c) CH2O (36–38% aqueous solution, 2.0 eq.), H2O/AcOH (1:1, v/v), HClconc (1.0 eq.), reflux, 5 h; (d) HBr (33% solution in AcOH), room temperature, 2 h; (e) propylene oxide; (f) SnCl2, EtOH, reflux, 3 h. Full article ">

20 pages, 3091 KiB

Open AccessArticle

Evaluation of Clay Hydration and Swelling Inhibition Using Quaternary Ammonium Dicationic Surfactant with Phenyl Linker

by Mobeen Murtaza, Hafiz Mudaser Ahmad, Muhammad Shahzad Kamal, Syed Muhammad Shakil Hussain, Mohamed Mahmoud and Shirish Patil

Molecules 2020, 25(18), 4333; https://doi.org/10.3390/molecules25184333 - 22 Sep 2020

Cited by 25 | Viewed by 4349

Abstract

Water-based drilling fluids are extensively used for drilling oil and gas wells. However, water-based muds cause clay swelling, which severely affects the stability of wellbore. Due to two adsorption positions, it is expected that cationic gemini surfactants can reduce the clay swelling. In [...] Read more.

Water-based drilling fluids are extensively used for drilling oil and gas wells. However, water-based muds cause clay swelling, which severely affects the stability of wellbore. Due to two adsorption positions, it is expected that cationic gemini surfactants can reduce the clay swelling. In this work, quaternary ammonium dicationic gemini surfactants containing phenyl linkers and different counterions (Cl⁻ and Br⁻) were synthesized, and the effect of variation in counterions on swelling and hydration properties of shales was studied. Numerous water-based drilling fluid formulations were prepared with different concentrations of surfactants to study the swelling inhibition capacity of surfactants. The performance of surfactant-containing drilling muds was evaluated by comparing them with base drilling mud, and sodium silicate drilling mud. Various experimental techniques were employed to study drilling mud characteristics such as rheology and filtration. The inhibition properties of drilling mud formulations were determined by linear swelling experiment, capillary suction time test, particle size distribution measurement, wettability measurements, and X-ray Diffraction (XRD). Experimental results showed that surfactant-based formulation containing bromide counterion exhibited superior rheological properties as compared to other investigated formulations. The filtration test showed that the gemini surfactant with chloride counterion had higher filtrate loss compared to all other formulations. The bentonite swelling was significantly reduced with increasing the concentration of dicationic surfactants as inhibitors, and maximum reduction in the linear swelling rate was observed by using a formulation containing surfactant with chloride counterion. The lowest capillary suction timer (CST) was obtained in the formulation containing surfactant with chloride counterion as less CST indicated the enhanced inhibition capacity. The particle size measurement showed that average bentonite particle size increased upon the addition of surfactants depicting the inhibition capacity. The increase in basal spacing obtained from XRD analysis showed the intercalation of gemini surfactants in interlayers of bentonite. The contact angle measurements were performed to study the wettability of the bentonite film surface, and the results showed that hydrophobicity increased by incorporating the surfactants to the drilling fluid. Full article

(This article belongs to the Special Issue New Frontiers Regarding Surfactants and Biosurfactants: Production, Characterization and Application)

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26 pages, 7326 KiB

Open AccessArticle

A Bottom-Up Synthesis Approach to Silver Nanoparticles Induces Anti-Proliferative and Apoptotic Activities Against MCF-7, MCF-7/TAMR-1 and MCF-10A Human Breast Cell Lines

by Nurul Izzati Zulkifli, Musthahimah Muhamad, Nur Nadhirah Mohamad Zain, Wen-Nee Tan, Noorfatimah Yahaya, Yazmin Bustami, Azlan Abdul Aziz and Nik Nur Syazni Nik Mohamed Kamal

Molecules 2020, 25(18), 4332; https://doi.org/10.3390/molecules25184332 - 22 Sep 2020

Cited by 25 | Viewed by 3435

Abstract

A bottom-up approach for synthesizing silver nanoparticles (AgNPs-GA) phytomediated by Garcinia atroviridis leaf extract is described. Under optimized conditions, the AgNPs-GA were synthesized at a concentration of 0.1 M silver salt and 10% (w/v) leaf extract, 1:4 mixing ratio [...] Read more.

A bottom-up approach for synthesizing silver nanoparticles (AgNPs-GA) phytomediated by Garcinia atroviridis leaf extract is described. Under optimized conditions, the AgNPs-GA were synthesized at a concentration of 0.1 M silver salt and 10% (w/v) leaf extract, 1:4 mixing ratio of reactants, pH 3, temperature 32 °C and 72 h reaction time. The AgNPs-GA were characterized by various analytical techniques and their size was determined to be 5–30 nm. FTIR spectroscopy indicates the role of phenolic functional groups in the reduction of silver ions into AgNPs-GA and in supporting their subsequent stability. The UV-Visible spectrum showed an absorption peak at 450 nm which reflects the surface plasmon resonance (SPR) of AgNPs-GA and further supports the stability of these biosynthesized nanoparticles. SEM, TEM and XRD diffractogram analyses indicate that AgNPs-GA were spherical and face-centered-cubic in shape. This study also describes the efficacy of biosynthesized AgNPs-GA as anti-proliferative agent against human breast cancer cell lines, MCF-7 and MCF-7/TAMR-1. Our findings indicate that AgNPs-GA possess significant anti-proliferative effects against both the MCF-7 and MCF-7/TAMR-1 cell lines, with inhibitory concentration at 50% (IC₅₀ values) of 2.0 and 34.0 µg/mL, respectively, after 72 h of treatment. An induction of apoptosis was evidenced by flow cytometry using Annexin V-FITC and propidium iodide staining. Therefore, AgNPs-GA exhibited its anti-proliferative activity via apoptosis on MCF-7 and MCF-7/TAMR-1 breast cancer cells in vitro. Taken together, the leaf extract from Garcinia atroviridis was found to be highly capable of producing AgNPs-GA with favourable physicochemical and biological properties. Full article

(This article belongs to the Special Issue Nanoparticles and Their Biological and Biomedical Applications)

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23 pages, 1182 KiB

Open AccessReview

Cyanobacterial Polyhydroxyalkanoates: A Sustainable Alternative in Circular Economy

by Diana Gomes Gradíssimo, Luciana Pereira Xavier and Agenor Valadares Santos

Molecules 2020, 25(18), 4331; https://doi.org/10.3390/molecules25184331 - 22 Sep 2020

Cited by 34 | Viewed by 6738

Abstract

Conventional petrochemical plastics have become a serious environmental problem. Its unbridled use, especially in non-durable goods, has generated an accumulation of waste that is difficult to measure, threatening aquatic and terrestrial ecosystems. The replacement of these plastics with cleaner alternatives, such as polyhydroxyalkanoates [...] Read more.

Conventional petrochemical plastics have become a serious environmental problem. Its unbridled use, especially in non-durable goods, has generated an accumulation of waste that is difficult to measure, threatening aquatic and terrestrial ecosystems. The replacement of these plastics with cleaner alternatives, such as polyhydroxyalkanoates (PHA), can only be achieved by cost reductions in the production of microbial bioplastics, in order to compete with the very low costs of fossil fuel plastics. The biggest costs are carbon sources and nutrients, which can be appeased with the use of photosynthetic organisms, such as cyanobacteria, that have a minimum requirement for nutrients, and also using agro-industrial waste, such as the livestock industry, which in turn benefits from the by-products of PHA biotechnological production, for example pigments and nutrients. Circular economy can help solve the current problems in the search for a sustainable production of bioplastic: reducing production costs, reusing waste, mitigating CO₂, promoting bioremediation and making better use of cyanobacteria metabolites in different industries. Full article

(This article belongs to the Special Issue Biobased Biodegradable Polymers)

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40 pages, 4116 KiB

Open AccessReview

The Efficacy of Cholesterol-Based Carriers in Drug Delivery

by Ngonidzashe Ruwizhi and Blessing Atim Aderibigbe

Molecules 2020, 25(18), 4330; https://doi.org/10.3390/molecules25184330 - 22 Sep 2020

Cited by 42 | Viewed by 5346

Abstract

Several researchers have reported the use of cholesterol-based carriers in drug delivery. The presence of cholesterol in cell membranes and its wide distribution in the body has led to it being used in preparing carriers for the delivery of a variety of therapeutic [...] Read more.

Several researchers have reported the use of cholesterol-based carriers in drug delivery. The presence of cholesterol in cell membranes and its wide distribution in the body has led to it being used in preparing carriers for the delivery of a variety of therapeutic agents such as anticancer, antimalarials and antivirals. These cholesterol-based carriers were designed as micelles, nanoparticles, copolymers, liposomes, etc. and their routes of administration include oral, intravenous and transdermal. The biocompatibility, good bioavailability and biological activity of cholesterol-based carriers make them potent prodrugs. Several in vitro and in vivo studies revealed cholesterol-based carriers potentials in delivering bioactive agents. In this manuscript, a critical review of the efficacy of cholesterol-based carriers is reported. Full article

(This article belongs to the Special Issue Natural Macromolecules for Medicine)

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15 pages, 2963 KiB

Open AccessArticle

Attempts to Target Staphylococcus aureus Induced Osteomyelitis Bone Lesions in a Juvenile Pig Model by Using Radiotracers

by Pia Afzelius, Aage Kristian Olsen Alstrup, Ole Lerberg Nielsen, Karin Michaelsen Nielsen and Svend Borup Jensen

Molecules 2020, 25(18), 4329; https://doi.org/10.3390/molecules25184329 - 21 Sep 2020

Cited by 4 | Viewed by 2818

Abstract

Background [¹⁸F]FDG Positron Emission Tomography cannot differentiate between sterile inflammation and infection. Therefore, we, aimed to develop more specific radiotracers fitted for differentiation between sterile and septic infection to improve the diagnostic accuracy. Consequently, the clinicians can refine the treatment of, [...] Read more.

Background [¹⁸F]FDG Positron Emission Tomography cannot differentiate between sterile inflammation and infection. Therefore, we, aimed to develop more specific radiotracers fitted for differentiation between sterile and septic infection to improve the diagnostic accuracy. Consequently, the clinicians can refine the treatment of, for example, prosthesis-related infection. Methods: We examined different target points; Staphylococcus aureus biofilm (⁶⁸Ga-labeled DOTA-K-A9 and DOTA-GSGK-A11), bone remodeling ([¹⁸F]NaF), bacterial cell membranes ([⁶⁸Ga]Ga-Ubiquicidin), and leukocyte trafficking ([⁶⁸Ga]Ga-DOTA-Siglec-9). We compared them to the well-known glucose metabolism marker [¹⁸F]FDG, in a well-established juvenile S. aureus induced osteomyelitis (OM) pig model. Results: [¹⁸F]FDG accumulated in the OM lesions seven days after bacterial inoculation, but disappointingly we were not able to identify any tracer accumulation in OM with any of the supposedly more specific tracers. Conclusion: These negative results are, however, relevant to report as they may save other research groups from conducting the same animal experiments and provide a platform for developing and evaluating other new potential tracers or protocol instead. Full article

(This article belongs to the Special Issue Past, Present, and Future of Radiochemical Synthesis)

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[68Ga]Ga-DOTA-K-A9 compared to [18F]FDG. Full article ">Figure 2
[68Ga]Ga-DOTA-GSGK-A11 compared to [18F]FDG. Full article ">Figure 3
Maximum intensity projections (MIPs) of [18F]FDG, [68Ga]Ga-DOTA-K-A9, and [68Ga]Ga-DOTA-GSGK-A11. Full article ">Figure 4
[68Ga]Ga-ubiquicidin and [18F]NaF compared to [18F]FDG. Full article ">Figure 5
MIPs of [68Ga]Ga-ubiquicidin, [18F]NaF, and [18F]FDG. Full article ">Figure 6
[68Ga]Ga-DOTA-Siglec-9 compared to [18F]FDG]. Full article ">Figure 7
[68Ga]Ga-DOTA-Siglec-9 uptake in the lungs. Full article ">Figure 8
[68Ga]Ga-DOTA-Siglec-9 compared to [18F]FDG. Full article ">

16 pages, 1701 KiB

Open AccessArticle

Techno-Economic Analysis of Producing Glacial Acetic Acid from Poplar Biomass via Bioconversion

by Rodrigo Morales-Vera, Jordan Crawford, Chang Dou, Renata Bura and Rick Gustafson

Molecules 2020, 25(18), 4328; https://doi.org/10.3390/molecules25184328 - 21 Sep 2020

Cited by 20 | Viewed by 6122

Abstract

Most of the current commercial production of glacial acetic acid (GAA) is by petrochemical routes, primarily methanol carbonylation. GAA is an intermediate in the production of plastics, textiles, dyes, and paints. GAA production from biomass might be an economically viable and sustainable alternative [...] Read more.

Most of the current commercial production of glacial acetic acid (GAA) is by petrochemical routes, primarily methanol carbonylation. GAA is an intermediate in the production of plastics, textiles, dyes, and paints. GAA production from biomass might be an economically viable and sustainable alternative to petroleum-derived routes. Separation of acetic acid from water is a major expense and requires considerable energy. This study evaluates and compares the technical and economic feasibility of GAA production via bioconversion using either ethyl acetate or alamine in diisobutylkerosene (DIBK) as organic solvents for purification. Models of a GAA biorefinery with a production of 120,650 tons/year were simulated in Aspen software. This biorefinery follows the path of pretreatment, enzymatic hydrolysis, acetogen fermentation, and acid purification. Estimated capital costs for different scenarios ranged from USD 186 to 245 million. Recovery of GGA using alamine/DIBK was a more economical process and consumed 64% less energy, due to lower steam demand in the recovery distillation columns. The estimated average minimum selling prices of GGA were USD 756 and 877/ton for alamine/DIBK and ethyl acetate scenarios, respectively. This work establishes a feasible and sustainable approach to produce GGA from poplar biomass via fermentation. Full article

(This article belongs to the Special Issue Lignocellulosic Biomass to Biofuels and Biochemicals)

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15 pages, 2061 KiB

Open AccessArticle

Synergistic Solubilization of Phenanthrene by Mixed Micelles Composed of Biosurfactants and a Conventional Non-Ionic Surfactant

by Jianfei Liu, Yuru Wang and Huifang Li

Molecules 2020, 25(18), 4327; https://doi.org/10.3390/molecules25184327 - 21 Sep 2020

Cited by 19 | Viewed by 2910

Abstract

This study investigated the solubilization capabilities of rhamnolipids biosurfactant and synthetic surfactant mixtures for the application of a mixed surfactant in surfactant-enhanced remediation. The mass ratios between Triton X-100 and rhamnolipids were set at 1:0, 9:1, 3:1, 1:1, 1:3, and 0:1. The ideal [...] Read more.

This study investigated the solubilization capabilities of rhamnolipids biosurfactant and synthetic surfactant mixtures for the application of a mixed surfactant in surfactant-enhanced remediation. The mass ratios between Triton X-100 and rhamnolipids were set at 1:0, 9:1, 3:1, 1:1, 1:3, and 0:1. The ideal critical micelle concentration values of the Triton X-100/rhamnolipids mixture system were higher than that of the theoretical predicted value suggesting the existence of interactions between the two surfactants. Solubilization capabilities were quantified in term of weight solubilization ratio and micellar-water partition coefficient. The highest value of the weight solubilization ratio was detected in the treatment where only Triton X-100 was used. This ratio decreased with the increase in the mass of rhamnolipids in the mixed surfactant systems. The parameters of the interaction between surfactants and the micellar mole fraction in the mixed system have been determined. The factors that influence phenanthrene solubilization, such as pH, ionic strength, and acetic acid concentration have been discussed in the paper. The aqueous solubility of phenanthrene increased linearly with the total surfactant concentration in all treatments. The mixed rhamnolipids and synthetic surfactants showed synergistic behavior and enhanced the solubilization capabilities of the mixture, which would extend the rhamnolipids application. Full article

(This article belongs to the Special Issue New Frontiers Regarding Surfactants and Biosurfactants: Production, Characterization and Application)

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Plots of surface tension as a function of the logarithm values of the total surfactant concentration of the single and TX100–Rham mixture at 10, 20, 30, 40, 50, 60, 80, 100, 200, 300, 400, 500, 1000, 1500, 2000, 2500, 3000 mg/L and with mass ratios of TX100 and Rham at 1:0; 9:1; 3:1; 1:1; 1:3; and 0:1, respectively. (γ: surface tension; C: total surfactant concentration; mTX100: the bulk mass fraction of TX100 in TX100 and rhamnolipids (Rham) mixture). Full article ">Figure 2
Solubilization of phenanthrene with total surfactant concentration at CMC, 500, 1000, 1500, 2000, 2500 and 3000mg/L, and with mass ratios of TX100 and rhamnolipids at 1:0; 9:1; 3:1; 1:1; 1:3; and 0:1, respectively (mTX100: the bulk mass fraction of TX100 in TX100 and rhamnolipids mixture). Full article ">Figure 3
Solubilization of phenanthrene with different pH value (5, 6, 7, 8, 9) in the TX100–Rham mixture at CMC, 500, 1000, 1500, 2000, 2500 and 3000 mg/L (the mass ratio between TX100 and rhamnolipids was 3:1). Full article ">Figure 4
Solubilization of phenanthrene with coexisting NaCl (5, 10, and 15 mg/L) in the TX100–rhamnolipids mixture at CMC, 500, 1000, 1500, 2000, 2500 and 3000 mg/L (the mass ratio between TX100 and rhamnolipids was 3:1, and CNaCl is the concentration of NaCl). Full article ">Figure 5
Solubilization of phenanthrene with coexisting acetic acid (5, 10, and 15 mg/L) in the TX100-Rham mixture at CMC, 500, 1000, 1500, 2000, 2500 and 3000 mg/L (the mass ratio between TX100 and Rham was 3:1, and CAC is the concentration of acetic acid). Full article ">

20 pages, 1734 KiB

Open AccessArticle

Comparative Phytochemical, Antioxidant and Haemostatic Studies of Preparations from Selected Vegetables from Cucurbitaceae Family

by Agata Rolnik, Iwona Kowalska, Agata Soluch, Anna Stochmal and Beata Olas

Molecules 2020, 25(18), 4326; https://doi.org/10.3390/molecules25184326 - 21 Sep 2020

Cited by 6 | Viewed by 3238

Abstract

The aim of this study was to provide detailed insight into the chemical composition and activity of five cucurbit vegetable preparations (pumpkin, zucchini, cucumber, white and yellow pattypan squash), each containing various phytochemical compounds with potential use against oxidative stress induced by the [...] Read more.

The aim of this study was to provide detailed insight into the chemical composition and activity of five cucurbit vegetable preparations (pumpkin, zucchini, cucumber, white and yellow pattypan squash), each containing various phytochemical compounds with potential use against oxidative stress induced by the hydroxyl radical donors in human plasma in vitro. We studied the antiradical capacity of vegetable preparations using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method. As oxidative stress may induce changes in hemostasis, our aim included the determination of their effect on three selected hemostatic parameters of plasma, which are three coagulation times: PT (prothrombin time), APTT (activated partial thromboplastin time) and TT (thrombin time). However, none of used vegetable preparations changed APTT, PT or TT compared to the control. The phytochemical composition of the tested preparations was determined by UPLC-ESI-QTOF-MS. In our in vitro experiments, while all five tested preparations had antioxidant potential, the preparation from yellow pattypan squash showed the strongest potential. All cucurbit vegetable preparations inhibited lipid peroxidation. Only zucchini did not have an effect on protein carbonylation and only yellow pattypan squash inhibited thiol oxidation. The antioxidant activity of cucurbits appears to have triggered significant interest in multiple applications, including CVDs (cardiovascular diseases) associated with oxidative stress, which can be treated by supplementation based on these vegetables. Full article

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The base-peak chromatogram (BPC) of the five cucurbit vegetable preparations, obtained using high resolution UHPLC-ESI-QTOF-MS in negative ionization mode: preparation from zucchini (A), preparation from yellow pattypan squash (B), preparation from white pattypan squash (C), preparation from pumpkin (D), and preparation from cucumber (E). Full article ">Figure 1 Cont.
The base-peak chromatogram (BPC) of the five cucurbit vegetable preparations, obtained using high resolution UHPLC-ESI-QTOF-MS in negative ionization mode: preparation from zucchini (A), preparation from yellow pattypan squash (B), preparation from white pattypan squash (C), preparation from pumpkin (D), and preparation from cucumber (E). Full article ">Figure 2
Effects of the five cucurbit vegetable preparations (concentration range 1–50 µg/mL, pre-incubation time 5 min) on the oxidative damages of plasma protein–protein carbonylation, in plasma treated with H2O2/Fe (incubation time-25 min) (A); on the oxidative damages of plasma proteins, the level of thiol groups in plasma treated with H2O2/Fe (incubation time 25 min) (B); and on lipid peroxidation in plasma treated with H2O2/Fe (incubation time 25 min) (C). Results are given as mean ± SE (n = 6). Control negative refers to plasma not treated with H2O2/Fe, whereas control positive to plasma treated with H2O2/Fe. One-way ANOVA followed by a multicomparison Tukey test and Kruskal–Wallis test: * p < 0.05, compared with positive control (treated with H2O2/Fe). Full article ">Figure 2 Cont.
Effects of the five cucurbit vegetable preparations (concentration range 1–50 µg/mL, pre-incubation time 5 min) on the oxidative damages of plasma protein–protein carbonylation, in plasma treated with H2O2/Fe (incubation time-25 min) (A); on the oxidative damages of plasma proteins, the level of thiol groups in plasma treated with H2O2/Fe (incubation time 25 min) (B); and on lipid peroxidation in plasma treated with H2O2/Fe (incubation time 25 min) (C). Results are given as mean ± SE (n = 6). Control negative refers to plasma not treated with H2O2/Fe, whereas control positive to plasma treated with H2O2/Fe. One-way ANOVA followed by a multicomparison Tukey test and Kruskal–Wallis test: * p < 0.05, compared with positive control (treated with H2O2/Fe). Full article ">Figure 3
Effects of the five cucurbit vegetable preparations (incubation time 30 min) on the plasma antioxidant capacity, measured as ORAC (oxygen radical antioxidant capacity) (A); on total antioxidant capacity of plasma (B). Results are given as mean ± SE (n = 5). One-way ANOVA followed by a multicomparison Tukey test and Kruskal–Wallis test, compared with control. The use of TLC-DPPH• assay for the detection of antioxidant activity of preparations from: 1-pumpkin, 2-zucchini, 3-cucumber, 4-white pattypan squash, 5-yellow pattypan squash. Standards: chlorogenic acid (CGA) and rutin (R) (C). Full article ">Figure 3 Cont.
Effects of the five cucurbit vegetable preparations (incubation time 30 min) on the plasma antioxidant capacity, measured as ORAC (oxygen radical antioxidant capacity) (A); on total antioxidant capacity of plasma (B). Results are given as mean ± SE (n = 5). One-way ANOVA followed by a multicomparison Tukey test and Kruskal–Wallis test, compared with control. The use of TLC-DPPH• assay for the detection of antioxidant activity of preparations from: 1-pumpkin, 2-zucchini, 3-cucumber, 4-white pattypan squash, 5-yellow pattypan squash. Standards: chlorogenic acid (CGA) and rutin (R) (C). Full article ">

20 pages, 2850 KiB

Open AccessArticle

The Effect of Cultivation Method of Strawberry (Fragaria x ananassa Duch.) cv. Honeoye on Structure and Degradation Dynamics of Pectin during Cold Storage

by Magdalena Drobek, Magdalena Frąc, Artur Zdunek and Justyna Cybulska

Molecules 2020, 25(18), 4325; https://doi.org/10.3390/molecules25184325 - 21 Sep 2020

Cited by 22 | Viewed by 4157

Abstract

The high quality and long shelf life of strawberry fruit are largely dependent on the cultivation method. The goal of this experiment was to study the effect of different cultivation methods on molecular structure and rheological properties of pectin extracted from strawberry quality [...] Read more.

The high quality and long shelf life of strawberry fruit are largely dependent on the cultivation method. The goal of this experiment was to study the effect of different cultivation methods on molecular structure and rheological properties of pectin extracted from strawberry quality parameters during cold storage. Three methods of cultivation of strawberry cv. Honeoye were tested: organic cultivation on raised beds, organic cultivation with the flat-planted method and conventional cultivation with the flat-planted method. The nanostructure of pectin (AFM), its chemical structure (FT-IR) and rheological properties were studied. The fruits were also tested by size, dry matter, firmness, acidity and the content of soluble solids, anthocyanin, phenolics, vitamin C and galacturonic acid. Pectin isolated from organic strawberries was more rapidly degraded than conventional strawberry pectin, which limits the possibilities for their processing and use as gelling or stabilizing agents at 20 °C. The differences in fruit quality were particularly noticeable with respect to the anthocyanin content, which was significantly higher for organic strawberry. The organic fruit also had better sensory properties because of its lower acidity and higher soluble solid content (SSC). These and other results from this experiment showed that strawberries produced by organic farming methods had better biochemical properties compared to conventional fruit; however, pectin transformation undergone faster limits their further technological applications. Full article

(This article belongs to the Special Issue Recent Advances on Natural Product Research)

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Scheme of quality testing of strawberries. Full article ">Figure 2
Fruit quality attributes. Average dry weight (A) and firmness (B) changes over storage time. T0—harvest day, T1–T12—days of sampling. Letters indicate the differences (a, b, c, d) between cultivation methods and storage days (p < 0.05), determined by Tukey’s HSD test. Data are means ± SD (n = 3). Full article ">Figure 3
FT-IR spectrum of pectin after extraction with ammonium oxalate from strawberries cv. Honeoye cultivated in three different ways on (A) the day of harvest (T0) and (B) the twelfth day of storage (T12). Full article ">Figure 4
AFM height images of pectin extracted with ammonium oxalate during cold storage; (a)—organic cultivation on raised beds T0, (b)—organic cultivation on raised beds T12, (c)—organic cultivation in a flat-planted plot T0, (d)—organic cultivation in a flat-planted plot T12, (e)—conventional cultivation in a flat-planted plot T0, (f)—conventional cultivation in a flat-planted plot T12. Full article ">Figure 5
Flow curves for pectin samples extracted with ammonium oxalate. The arrow indicates the direction of the line. T0—harvest day, T12—last day of the experiment. Full article ">

17 pages, 1117 KiB

Open AccessArticle

Skin Damages—Structure Activity Relationship of Benzimidazole Derivatives Bearing a 5-Membered Ring System

by Ernestine Nicaise Djuidje, Elisa Durini, Sabrina Sciabica, Elena Serra, Jan Balzarini, Sandra Liekens, Stefano Manfredini, Silvia Vertuani and Anna Baldisserotto

Molecules 2020, 25(18), 4324; https://doi.org/10.3390/molecules25184324 - 21 Sep 2020

Cited by 14 | Viewed by 3209

Abstract

In the search for scaffolds for multifunctional compounds we investigated the structure activity relationship of a class of benzimidazole derivatives bearing 5-membered ring. The newly synthesized and the already known compounds were divided into three classes that present different substituent at 5 position [...] Read more.

In the search for scaffolds for multifunctional compounds we investigated the structure activity relationship of a class of benzimidazole derivatives bearing 5-membered ring. The newly synthesized and the already known compounds were divided into three classes that present different substituent at 5 position of the benzimidazole ring (-H, -COOH or –SO₃H) and different heterocycle at position 2 (thiophene, furan or pyrrole). All the derivatives were synthesized and tested to determine their photoprotective profile against UV rays, in vitro antioxidant capacity against different radicals (DPPH and FRAP test), antifungal inhibitory activity (dermatophytes and Candida albicans), antiviral and antiproliferative activity. A Structure-Activity Relationship study indicated compound 10, bearing a pyrrole heterocycle on the benzimidazole ring, as the best multifunctional derivative of the series and as potential candidate for the development of drugs especially in case of melanoma. Full article

(This article belongs to the Special Issue Nitrogen-Containing Heterocycles as Significant Molecular Scaffolds for Medicinal and Other Applications)

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40 pages, 9284 KiB

Open AccessReview

Boronic Acids and Their Derivatives in Medicinal Chemistry: Synthesis and Biological Applications

by Mariana Pereira Silva, Lucília Saraiva, Madalena Pinto and Maria Emília Sousa

Molecules 2020, 25(18), 4323; https://doi.org/10.3390/molecules25184323 - 21 Sep 2020

Cited by 93 | Viewed by 17035

Abstract

Boron containing compounds have not been widely studied in Medicinal Chemistry, mainly due to the idea that this group could confer some toxicity. Nowadays, this concept has been demystified and, especially after the discovery of the drug bortezomib, the interest for these compounds, [...] Read more.

Boron containing compounds have not been widely studied in Medicinal Chemistry, mainly due to the idea that this group could confer some toxicity. Nowadays, this concept has been demystified and, especially after the discovery of the drug bortezomib, the interest for these compounds, mainly boronic acids, has been growing. In this review, several activities of boronic acids, such as anticancer, antibacterial, antiviral activity, and even their application as sensors and delivery systems are addressed. The synthetic processes used to obtain these active compounds are also referred. Noteworthy, the molecular modification by the introduction of boronic acid group to bioactive molecules has shown to modify selectivity, physicochemical, and pharmacokinetic characteristics, with the improvement of the already existing activities. Besides, the preparation of compounds with this chemical group is relatively simple and well known. Taking into consideration these findings, this review reinforces the relevance of extending the studies with boronic acids in Medicinal Chemistry, in order to obtain new promising drugs shortly. Full article

(This article belongs to the Special Issue Breakthroughs in Medicinal Chemistry: New Targets and Mechanisms, New Drugs, New Hopes 2020)

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