Elena Stashenko
Universidad Industrial de Santander, Chemistry, Faculty Member
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Research Interests: Chemistry, Cytotoxicity, Medicine, Phytochemical, Toxins, and 3 moreDPPH, Zearalenone, and Viability assay
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Research Interests: Botany, Chemistry, Organic Chemistry, Cultivar, Molecules, and 10 moreQuercetin, Flavonoid, Trolox, Flavonols, Anthocyanin, Catechin, Petal, Anthocyanidin, Kaempferol, and cyanidin
ABSTRACT Croton malambo (Karst), is a small tree that grows in the northern Colombian coast and eastern Venezuela. Hydrodistillation (HD), microwave-assisted hydrodistillation (MWHD), simultaneous distillation-solvent extraction (SDE) and... more
ABSTRACT Croton malambo (Karst), is a small tree that grows in the northern Colombian coast and eastern Venezuela. Hydrodistillation (HD), microwave-assisted hydrodistillation (MWHD), simultaneous distillation-solvent extraction (SDE) and supercritical fluid (CO2) extraction (SFE), were employed to isolate volatile secondary metabolites from Colombian C. malambo (Karst) barks. The essential oil and extracts were analyzed by GC-MS. More than 20 individual components in the various extracts were identified. Methyl eugenol was the main component found in the HD and MWHD essential oils (63.5, 74.6 %), SDE and SFE extracts (67.1 and ca. 67.9 %trans-β-caryophyllene (2.5, 2.6, 2.1 and 6.5 %) and trans-methyl isoeugenol (1.5, 1.9, 3.2 and 4.2 %). The oil obtained by HD presented a mean lethal concentration (LC50) against Artemia franciscana of 15.32 µg/mL and 2.20 µg/mL after 24 and 48 h exposition, respectively. These results show that C. malambo essential oil is an excellent source of methyl eugenol, but it is moderately cytotoxic. In addition, was evaluated the repellent activity of C. malambo essential oils against an important stored-product insect pest: Tribolium castaneum Herbst. These oils had high repellent effects on T. castaneum (92 % ± 3) at 0.2 µL/cm2 after 4 h of exposure.
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ABSTRACT Essential oil from the leaves of Morina longifolia was isolated (yield 1.43%) using the hydro-distillation method and analyzed for its chemical composition by capillary GC-FID and GC-MS. The oil showed the presence of 47... more
ABSTRACT Essential oil from the leaves of Morina longifolia was isolated (yield 1.43%) using the hydro-distillation method and analyzed for its chemical composition by capillary GC-FID and GC-MS. The oil showed the presence of 47 compounds representing 82.29% area of total chromatogram. The oil was dominated by sesquiterpenes amounting to 53.02% with germacrene D (20.74%), α-cadinol (4.09%), and germacrene D-4-ol (3.73%) as major constituents. The composition and characteristic odor of the oil is indicative of its use in fragrance applications.
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Chromatographic (GC/flame ionization detection, GC/MS) and statistical analyses were applied to the study of essential oils and extracts obtained from flowers, leaves, and stems of Lippia origanoides plants, growing wild in different... more
Chromatographic (GC/flame ionization detection, GC/MS) and statistical analyses were applied to the study of essential oils and extracts obtained from flowers, leaves, and stems of Lippia origanoides plants, growing wild in different Colombian regions. Retention indices, mass spectra, and standard substances were used in the identification of 139 substances detected in these essential oils and extracts. Principal component analysis allowed L. origanoides classification into three chemotypes, characterized according to their essential oil major components. α‐ and β‐phellandrenes, p‐cymene, and limonene distinguished chemotype A; carvacrol and thymol were the distinctive major components of chemotypes B and C, respectively. Pinocembrin (5,7‐dihydroxyflavanone) was found in L. origanoides chemotype A supercritical fluid (CO2) extract at a concentration of 0.83±0.03 mg/g of dry plant material, which makes this plant an interesting source of an important bioactive flavanone with diverse potential applications in cosmetic, food, and pharmaceutical products.
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Currently, there are no therapies to prevent severe dengue disease. Essential oils (EOs) can serve as primary sources for research and the discovery of phytomedicines for alternative therapy. Fourteen EOs samples were obtained by... more
Currently, there are no therapies to prevent severe dengue disease. Essential oils (EOs) can serve as primary sources for research and the discovery of phytomedicines for alternative therapy. Fourteen EOs samples were obtained by distillation from six plants used in Colombian folk medicine. GC/MS analysis identified 125 terpenes. Cytopathic effect (CPE) reduction assays revealed differences in antiviral activity. EOs of Lippia alba, citral chemotype and carvone-rich fraction; Lippia origanoides, phellandrene chemotype; and Turnera diffusa, exhibited strong antiviral activity (IC50: 29 to 82 µg/mL; SI: 5.5 to 14.3). EOs of Piper aduncum, Ocimum basilicum, and L. origanoides, carvacrol, and thymol chemotypes, exhibited weak antiviral activity (32 to 53% DENV-CPE reduction at 100 µg/mL; SI > 5.0). Cluster and one-way ANOVA analyses suggest that the strong antiviral activity of EOs could be attributed to increased amounts of non-phenolic oxygenated monoterpenes and sesquiterpene hydr...
Research Interests: Chemistry, Organic Chemistry, Essential Oil, TERPENE, Molecules, and 4 moreChemotype, Thymol, Carvacrol, and Citral
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The objective of this work was to evaluate DNA protective properties against UVR-induced genotoxicity of an L. origanoides extract obtained by CO2-supercritical fluid extraction and its major constituent, pinocembrin. L. origanoides... more
The objective of this work was to evaluate DNA protective properties against UVR-induced genotoxicity of an L. origanoides extract obtained by CO2-supercritical fluid extraction and its major constituent, pinocembrin. L. origanoides extract composition was determined by gas chromatography-mass spectrometry (GC-MS) and its antigenotoxic effect using the SOS chromotest. Fluorescence microscopy analysis was also used in cell treatments in order to determine interferences with cell division and different nucleoid shapes categories were measured. The principal constituents of the plant extract were pinocembrin (54.9%), trans-β- caryophyllene (10.9%), carvacrol (6.3%), p-cimene (6.2%), thymol (4.6%), and 1,8-cineole (3.5%). L. origanoides extract protected bacterial cells against UVR-induced genotoxicity at doses between 0.016 and 1 mg/mL; this effect was related to its major constituent pinocembrin. Fluorescence microscopy analysis showed that pinocembrin modulated the cell division and nucleoid shape in E. coli cells. The results were discussed in relation to the DNA protective potential of the L. origanoides species.Departamento Administrativo de Ciencia, Tecnología e Innovación [CO] Colciencias5507-543-31904Programa: Bioprospección y desarrollo de ingredientes naturales para las industrias cosmética, farmacéutica y de productos de aseo con base en la biodiversidad colombianan
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Salvia is a cosmopolitan and important genus, widely used in flavoring and traditional medicine for treatments of respiratory and gastrointestinal diseases. The present work evaluated the chemical composition of Salvia aratocensis extract... more
Salvia is a cosmopolitan and important genus, widely used in flavoring and traditional medicine for treatments of respiratory and gastrointestinal diseases. The present work evaluated the chemical composition of Salvia aratocensis extract obtained by supercritical CO2 extraction, as well as its DNA protective effect against ultraviolet radiation (UVR)-induced genotoxicity. S. aratocensis extract composition was determined by gas chromatography-mass spectrometry (GCMS). The antigenotoxic effect of S. aratocensis extract was assayed in co-incubation procedures using the SOS chromotest in Escherichia coli PQ37 cells. The major components of the plant extract were α-cadinol (31.8%), 1,10-epi-cubenol (12.9%), trans-β-caryophyllene (7.7%), -cadinene (6.6%), and squalene (6.5%). S. aratocensis extract protected bacterial cells against UVR-induced genotoxicity at doses between 0.063 and 1 mg/mL. The results were discussed in relation to the DNA protective potential of the S. aratocensis extract and its major constituents.Departamento Administrativo de Ciencia, Tecnología e Innovación [CO] Colciencias5507-543-31904Programa: Bioprospección y desarrollo de ingredientes naturales para las industrias cosmética, farmacéutica y de productos de aseo con base en la biodiversidad colombianan
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En este trabajo se estimo el contenido total de fenoles (CTF) por el ensayo Folin – Ciocalteau, y la actividad antioxidante mediante el ensayo de decoloracion del cation – radical ABTS, de extractos etanolicos y aceites esenciales de... more
En este trabajo se estimo el contenido total de fenoles (CTF) por el ensayo Folin – Ciocalteau, y la actividad antioxidante mediante el ensayo de decoloracion del cation – radical ABTS, de extractos etanolicos y aceites esenciales de especies del genero Piper recolectadas en la region de la Orinoquia. Los valores de CTF obtenidos para los extractos etanolicos de P. eriopodon, P. phytolaccifolium Opiz, P. sp., P. metanum y P. hispidum Sw fueron respectivamente: 7.3 ± 0.4, 2.0 ± 0.2, 8.5 ± 0.8, 11.4 ± 2.2 y 11.7 ± 0,6 (g AG / 100 g extracto) y para la actividad antioxidante, 0.0043 ± 0.0003, 0.0025 ± 0.0003, 0.004 ± 0.001, 0.0023 ± 0.0003 0.00419 ± 0.00005 (mmol Trolox / kg de sustancia). Para aceites esenciales se evaluo el CTF para P. eriopodon, P. sp., P. metanum, P. hispidum Sw y P. obstusilimbum, se obtuvieron los siguientes valores respectivamente: 2.35 ± 0.56, 4.01 ± 0.30, 1.16 ± 0.03, 1.23 ± 0.20 y 2.04 ± 0.10 (g AG / 100 g extracto). Ademas, se presenta el analisis composicio...
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The aqueous extract of fallen leaves from Fridericia chica (Bonpl.) L.G. Lohmann is utilized as a remedy in communities at northern Colombia. Traditional uses include wound healing, gastrointestinal inflammation, leukemia and psoriasis,... more
The aqueous extract of fallen leaves from Fridericia chica (Bonpl.) L.G. Lohmann is utilized as a remedy in communities at northern Colombia. Traditional uses include wound healing, gastrointestinal inflammation, leukemia and psoriasis, among others. The aims of this research were to evaluate the potential of the aqueous extract of fallen leaves of F. chica (AEFchica) to inhibit ethoxylated nonylphenol (Tergitol)-induced toxicity in Caenorhabditis elegans; and to identify its main components. The pharmacological properties of AEFchica was evaluated using a Tergitol-induced toxicity model in Caenorhabditis elegans. Lethality, locomotion, reproduction, and DAF-16 nuclear translocation were quantified. The chemical composition of AEFchica was carried out using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. AEFchica induced very little lethality on C. elegans (5.6%) even at high concentrations (10,000 μg/mL). The extract had no effect on locomotion impairing induced by ethoxylated nonylphenol. However, AEFchica (1000 μg/mL) abrogated Tergitol-induced mortality, recovering up to 53.3% of the nematodes from lethality induced by 10 mM Tergitol. Similarly, it also blocked Tergitol-dependent reproduction inhibition (82.1% recovery), as well as DAF-16 nuclear translocation (>95%), suggesting a prominent role on oxidative stress control. The chemical analysis indicated the presence of a great variety of molecules with known antioxidant, metabolic and immune modulator properties, such as hydroxylated methoxy flavones, N-methyl-1-deoxynojirimycin, and rehmaionoside A. In short, the aqueous extract of F. chica protects C. elegans from the deleterious effects of Tergitol on lethality, reproduction and oxidative stress involving DAF-16-mediated pathway. This extract is a promising source of bioactive phytochemicals for multi-target pharmacological purposes.
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Abstract Introduction Plants can be sources of photoprotective/antigenotoxic compounds that prevent cellular mutations involved in skin cancer and aging by regulating UV-induced mutability. Purpose The study was aimed at investigating the... more
Abstract Introduction Plants can be sources of photoprotective/antigenotoxic compounds that prevent cellular mutations involved in skin cancer and aging by regulating UV-induced mutability. Purpose The study was aimed at investigating the sunscreen properties of plants growing in Colombia. Materials and methods Ultraviolet (UV) radiation-absorption capability of different plant extracts was examined. In vitro photoprotection efficacies were evaluated using in vitro indices such as sun protection factor (SPFin vitro) and critical wavelength (λc). Pearson correlation analysis was used to examine the relationship between SPFin vitro and complementary UVB- antigenotoxicity estimates (%GI) based on the SOS Chromotest database. The cytotoxicity in human fibroblasts was studied using the trypan blue exclusion assay. Major compounds of promising plant extracts were determined by gas chromatography coupled to mass spectrometry (GC/MS). Results We showed that plant extracts have sunscreen properties against UVB, whereas broad-spectrum radiation protection efficacy was poor. SPFin vitro and %GI were correlated (R = 0.71, p < .0001) for the plant extracts under study. Three extracts obtained from Achyrocline satureioides, Chromolaena pellia, and Lippia origanoides species resulted to possess high protection efficacy and relatively low cytotoxicity in human fibroblasts. These plant extracts contained major compounds such as α-pinene, trans-β-caryophyllene, γ-muurolene, γ-cadinene and caryophyllene oxide in A. Satureioides extract, trans-β-caryophyllene, caryophyllene oxide, squalene and α-amyrin in C. pellia extract, and p-cymene, carvacrol, trans-β-caryophyllene and pinocembrin in L. origanoides extract. Conclusions Plants growing in Colombia contain compounds that can be useful for potential sunscreens. SPFin vitro and %GI estimates were correlated, but %GI estimates were more sensitive to detecting activity at lower plant extract concentrations. Our results supported the need to use DNA damage detection assays as a complement to photoprotection efficacy measurement.
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Background: Lippia origanoides H. B. K. (Verbenaceae) is an aromatic small shrub appreciated in the traditional systems of medicine. L. origanoides essential oil is an ingredient of commercial poultry feed products and its... more
Background: Lippia origanoides H. B. K. (Verbenaceae) is an aromatic small shrub appreciated in the traditional systems of medicine. L. origanoides essential oil is an ingredient of commercial poultry feed products and its postdistillation residual biomass is an interesting source of bioactive compounds. During our search for the valorization of this residual biomass, supercritical-CO2(SC-CO2)extraction afforded a mixture that was subjected to an investigation of phytochemicals and of cytotoxicity, which was not reported previously. Objectives: The current study was designed to investigate the phytochemicals from the steam-distilled residual biomass of thymol- and carvacrol-rich L. origanoides chemotypes and to evaluate their in vitro cytotoxic activity. Materials and Methods: Steam-distilled aerial parts of L. origanoides chemotypes were extracted with SC-CO2to obtain a greenish-yellow extract with a strong aromatic odor. The SC-CO2extract was subjected to column chromatography, and the isolate obtained was screened in vitro for cytotoxicity against human normal embryonic kidney 293, MRC-5, THP-1, and XP4PA cell lines, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Results: A pentacyclic triterpene, friedelan-3-one (1) was isolated for the first time from L. origanoides chemotypes. The structure of the isolate was elucidated with spectroscopic (ultraviolet, infrared, mass spectra, and nuclear magnetic resonance) techniques. The in vitro cytotoxic activity of the isolated compound was determined. The results showed no significant results against the selected cell lines using the MTT assay. Conclusion: The main significance of the present study was to develop promising routes to utilize the residual biomass for value-addition. This is the first report of friedelan-3-one isolation from the genus Lippia.
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Recent advances in the development of in vivo sampling methods for flavor constituents are reviewed. The different techniques available are presented together with representative examples of their application. Currently available sampling... more
Recent advances in the development of in vivo sampling methods for flavor constituents are reviewed. The different techniques available are presented together with representative examples of their application. Currently available sampling and analysis techniques for in vivo sampling permit the study of volatile and nonvolatile flavor components, their release, and interaction. Flavor release from foods can be followed in real time, which permits studies on the development of flavor perception and how it is affected by food composition, its mechanical properties, enzymatic processes, and other variables.
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Oil exploitation, drilling, transportation, and processing in refineries produces a complex mixture of chemical compounds, including polycyclic aromatic hydrocarbons (PAHs), which may affect the health of populations living in the zone of... more
Oil exploitation, drilling, transportation, and processing in refineries produces a complex mixture of chemical compounds, including polycyclic aromatic hydrocarbons (PAHs), which may affect the health of populations living in the zone of influence of mining activities (PZOI). Thus, to better understand the effects of oil exploitation activities on cytogenetic endpoint frequency, we conducted a biomonitoring study in the Hitnü indigenous populations from eastern Colombia by using the cytokinesis micronucleus cytome assay (CBMN-cyt). PAH exposure was also measured by determine urine 1-hydroxypyrene (1-OHP) using HPLC. We also evaluated the relationship between DNA damage and 1-OHP levels in the oil exploitation area, as well as the modulating effects of community health factors, such as Chagas infection; nutritional status; and consumption of traditional hallucinogens, tobacco, and wine from traditional palms. The frequencies of the CBMN-cyt assay parameters were comparable between P...
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ABSTRACT
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Headspace (HS), extractive, and distillative methods were employed to isolate volatile and semivolatile compounds from fresh Coffea arabica flowers. Static HS solid‐phase microextraction (HS‐SPME), microwave‐assisted HS‐SPME (MW‐HS‐SPME)... more
Headspace (HS), extractive, and distillative methods were employed to isolate volatile and semivolatile compounds from fresh Coffea arabica flowers. Static HS solid‐phase microextraction (HS‐SPME), microwave‐assisted HS‐SPME (MW‐HS‐SPME) with simultaneous hydrodistillation, and extraction with hexane or supercritical CO2‐isolated mixtures in which around 150 different chemical substances were identified or tentatively identified by GC–MS analysis. n‐Pentadecane (20–37% relative peak area, RPA) was the most abundant compound in the HS fractions from fresh flowers, followed by 8‐heptadecene (8–20% RPA) and geraniol (6–14% RPA). Hydrocarbons (mostly C13–C30 paraffins) were the predominant compound class in all the sorptive extractions (HS‐SPME, MW‐HS‐SPME, distillate), followed by terpenoids or oxygenated compounds (which varied with the isolation technique). Caffeine, a distinctive component of coffee fruits and beans, was also found in relatively high amounts in the supercritical CO2 extract of C. arabica flowers.
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Subcritical (CO(2)) extraction, carried out in a J&amp;W Scientific High Pressure Soxhlet Extractor, was used to isolate secondary metabolites from leaves, flowers, stems and roots of Colombian rue (Ruta graveolens L.). The various... more
Subcritical (CO(2)) extraction, carried out in a J&amp;W Scientific High Pressure Soxhlet Extractor, was used to isolate secondary metabolites from leaves, flowers, stems and roots of Colombian rue (Ruta graveolens L.). The various extracts were analyzed by capillary chromatography, on an HP-5 (30 m) column, using nitrogen-phosphorus, flame ionization, and mass selective detection systems. Kováts indexes and mass spectra (electron impact, 70 eV) were employed for compound identification. The extracts from the various parts of rue studied had different compositions. The number of compounds detected at concentrations above 0.01% (w/w) in the extracts from leaves, flowers, stems and roots, was 78, 45, 25 and 24, respectively. 2-Nonanone (8.9%), 2-undecanone (13.4%), chalepensin (13.0%), and geijerene (19.3%) were the main constituents found in the extracts from rue leaves, flowers, stems and roots, respectively. Furanocoumarins, furoquinolines, hydrocarbons and benzodioxol derivatives were the main compound families found in all extracts, at total concentrations between 3.7 and 33.9%, depending on the part of the plant. The extraction method used has low environmental impact and produced solvent-free extracts in good yield with no pigments, waxes, resins, or high-molecular weight compounds which may interfere with the isolation and analysis of the alkaloids responsible for rue&#39;s biological activity, which were extracted in relatively high yield.
Research Interests: Chemistry, High Pressure, Carbon Dioxide, Chromatography, Medicine, and 15 morePhosphorus, Nitrogen, Alkaloids, Gas Chromatography, Secondary Metabolites, Environmental Impact, Plant extracts, Time Factors, Gas Chromatography/mass Spectrometry, Extraction Method, Biological activity, Biochemistry and cell biology, Ruta graveolens, High Molecular Weight, and Capillary gas chromatography
The use of derivatization in the solid phase or in solution in analytical methods based on solid-phase microextraction (SPME) has made possible low detection limits (LODs) to determine substances with poor chromatographic behavior, high... more
The use of derivatization in the solid phase or in solution in analytical methods based on solid-phase microextraction (SPME) has made possible low detection limits (LODs) to determine substances with poor chromatographic behavior, high reactivity and/or volatility or thermal instability. The most common use of derivatization in SPME applications is the treatment of polar compounds to increase their recoveries from
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Research Interests: Engineering, Chemistry, Chromatography, Mass Spectrometry, Pharmacognosy, and 15 morePhosphorus, Solvent Extraction, STEM, Nitrogen, Gas Chromatography, Chemical Analysis, Secondary Metabolites, CHEMICAL SCIENCES, Supercritical Fluid Extraction, Extraction Method, Indexation, Steam Distillation, Supercritical Fluid, Flor, and Capillary gas chromatography
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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... 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 myc...
Research Interests: Chemistry, Organic Chemistry, Medicine, Ganoderma, Aroma, and 3 moreMolecules, Biotransformation, and Mycelium
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Stickiness of vegetative tissues has evolved multiple times in different plant families but is rare and understudied in flowers. While stickiness in general is thought to function primarily as a defense against herbivores, it may... more
Stickiness of vegetative tissues has evolved multiple times in different plant families but is rare and understudied in flowers. While stickiness in general is thought to function primarily as a defense against herbivores, it may compromise mutualistic interactions (such as those with pollinators) in reproductive tissues. Here, we test the hypothesis that stickiness on flower petals of the High-Andean plant, Bejaria resinosa (Ericaceae), functions as a defense against florivores. We address ecological consequences and discuss potential trade-offs associated with a repellant trait expressed in flowers that mediate mutualistic interactions. In surveys and manipulative experiments, we assess florivory and resulting fitness effects on plants with sticky and non-sticky flowers in different native populations of B. resinosa in Colombia. In addition, we analyze the volatile and non-volatile components in sticky and non-sticky flower morphs to understand the chemical information context wit...
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Background H. brasiletto is used in popular culture due to its therapeutic properties, including antioxidant, anti-inflammatory and antiproliferative properties, although little is known about its role as a protector against metal... more
Background H. brasiletto is used in popular culture due to its therapeutic properties, including antioxidant, anti-inflammatory and antiproliferative properties, although little is known about its role as a protector against metal toxicity. This study aimed to investigate the chemical composition and efficacy of the hydroalcoholic extract from H. brasiletto (HAE-Hbrasiletto) collected in northern Colombia to defend against cadmium (Cd)-induced toxicity. Methods Phytochemical characterization was performed using HPLC-ESI-QTOF. Caenorhabditis elegans was employed to assess the shielding effect of HAE-Hbrasiletto against Cd toxicity in vivo, and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was utilized to measure radical scavenging activity. Results The main secondary metabolites identified by HPLC-ESI-QTOF in the extracts were hematoxylins (brazilein and hematein) and protosappanins (protosappanin A, B and C, 10-O-methylprotosappanin B, and protosappanin A dimethyl acetal). The HAE-...
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espanolIntroduccion: la consulta de un particular que trajo un producto fitoterapeutico a base de calendula cuyo consumo le causo fuertes reacciones adversas, origino esta investigacion sobre la composicion de este producto. Objetivo:... more
espanolIntroduccion: la consulta de un particular que trajo un producto fitoterapeutico a base de calendula cuyo consumo le causo fuertes reacciones adversas, origino esta investigacion sobre la composicion de este producto. Objetivo: caracterizar la composicion quimica de muestras de lotes diferentes de un producto comercial denominado fitoterapeutico a base de calendula (Calendula officinalis) (PFC)comercializado en Colombia. Metodologia:se analizaron tabletas de ocho cajas del PFC de cuatro lotes diferentes de produccion (2017 y 2018). Se llevo a cabo el analisis de espacio de cabeza (HS) de tabletas por microextraccion en fase solida (SPME), con una fibra PDMS/DVB (65 μm), expuesta al HS de la muestra durante 30 min a 50 °C. Las fracciones volatiles se analizaron por cromatografia de gases acoplada a espectrometria de masas (GC/MS). Los extractos de tabletas obtenidos con mezcla de metanol:agua (1:1, v/v) se analizaron por cromatografia liquida (LC) de alta (HPLC) y ultra-alta e...
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Post-weaning diarrhea (PWD) is an often disease affecting piglets. It is caused mainly by enterotoxigenic Escherichia coli (ETEC) colonization in pig gut. Antibiotics has been used to prevent, combat and control PWD and its negative... more
Post-weaning diarrhea (PWD) is an often disease affecting piglets. It is caused mainly by enterotoxigenic Escherichia coli (ETEC) colonization in pig gut. Antibiotics has been used to prevent, combat and control PWD and its negative impact on the productivity of pig breeding sector. Nonetheless, antibiotics due to their wide antibacterial spectrum also can reach beneficial gut bacteria, such as Lactobacillus. Lately, essential oils (EOs) have emerged as a potential alternative to using antibiotics in animal breeding because of their effect on bacterial growth. Commonly, citrus EOs are by-products of food industry and the availability of these EOs in the worldwide market is huge. Thus, six commercials citrus EOs were evaluated on ETEC strains, as model of pathogenic bacteria, and on Lactobacillus species, as models of beneficial bacteria. In overall, citrus EOs exhibited a selective antibacterial activity with higher effect on pathogenic bacteria (ETECs) than beneficial bacteria (Lac...
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Land-use change and pesticides have been identified as two of the main causes behind pollinator decline. Understanding how these factors affect crop pollinator communities is crucial to inform practices that generate optimal pollination... more
Land-use change and pesticides have been identified as two of the main causes behind pollinator decline. Understanding how these factors affect crop pollinator communities is crucial to inform practices that generate optimal pollination and ensure sustainable food production. In this study, we investigated the effects of landscape composition and pesticide residues on bee communities and their pollination services in Solanum quitoense “lulo” crops in Colombia. On 10 farms, located along a gradient of landscape complexity that varied from 0.15 to 0.62 in their natural habitat proportion, we characterized the bee community visiting the crop, and carried out pollination experiments with bagged and open inflorescences to later estimate fruit set, weight, and diameter at every site. Additionally, we performed pesticide analysis on collected anthers through liquid chromatography to estimate pesticide risk coming from the crop fields using hazard quotients (HQ). Bee abundance and species r...
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RESUMEN Colombia posee gran diversidad de plantas medicinales, pero pocas han sido objeto de investigación. En este trabajo se evaluó la actividad antiproliferativa de aceites esenciales obtenidos por hidrodestilación asistida por... more
RESUMEN Colombia posee gran diversidad de plantas medicinales, pero pocas han sido objeto de investigación. En este trabajo se evaluó la actividad antiproliferativa de aceites esenciales obtenidos por hidrodestilación asistida por microondas. Se analizaron 15 muestras de 11 especies en ensayos del MTT en células cancerosas MCF-7, HeLa y HepG-2 y se incluyeron células normales humanas (HEK293) y de animales (Vero y BF16F10) para evaluar selectividad. La composición química de muestras activas se determinó por cromatografía de gases acoplada a espectrometría de masas (GC-MS). Aceites esenciales de cuatro especies mostraron actividad antiproliferativa (CI 50 : 50 μg/mL) en células HeLa y/o MCF-7, en el siguiente rango (índice de selectividad en paréntesis): Piper cumanense H.B.K. (4,7) > Piper subflavum var. espejuelanum C.DC (3,9) > Salvia officinalis L. (3,6) > Piper eriopodom (Miq.) C. DC. (3,1). Ninguna muestra fue activa en células HepG-2. El análisis por CG-MS identificó β-cariofileno, α-copaeno, β-pineno, α-pineno y linalol como componentes mayoritarios. Los aceites esenciales activos pueden ser puntos de partida para desarrollo de medicamentos herbales para cuidado paliativo del cáncer. ABSTRACT Colombia has a great diversity of medicinal plants, but few have been investigated. In this work, the antiproliferative activity of essential oils obtained by microwave-assisted hydrodistillation was evaluated. Fifteen samples from 11 species were analyzed in MTT assays in cancer cells MCF-7, HeLa and HepG-2, and normal human cells (HEK293) and animal cells (Vero and B16F10) were included to evaluate selectivity. The chemical composition of the active oils was determined by gas chromatography coupled to mass spectrometry (GC-MS). Essential oils from four species showed antiproliferative activity (IC 50 : <50 μg / mL) in HeLa and / or MCF-7 cells, in the following range (selectivity index in parenthesis): Piper cumanense H.B.K. (4.7) > Piper subflavum var. espejuelanum C. DC (3.9) > Salvia officinalis Linneo. (3.6) > Piper eriopodom (Miq.) C.DC. (31). The CG-MS analysis identified β-caryophyllene, α-copaene, β-pinene, α-pinene and linalool as major components. Active essential oils could serve as starting points to develop herbal medicines for cancer palliative care.