- Bulgaria
- University of Food Technologies - Plovdiv, Organic chemistry, Faculty Memberadd
- Organic Chemistry, Plant biotechnology, Solid phase extractions, HPLC method validations, GC-MS, Information Extraction, and 32 moreAntioxidants, Biological Activities of Alkaloids and Alkaloids-Containing Compounds, Food Science and Technology, Chemistry, Biotechnology, Biochemistry, Food and Nutrition, Analytical Chemistry, Biology, Physics, Molecular Biology, Chemical Engineering, Ecology, Conservation Biology, Biodiversity, Evolutionary Biology, Microbiology, Alkaloids, Carotenoids, tocopherol/vitamin E, Inulin or Oligofructose, TLC-Densitometery, Amarillidaceae Alkaloids, Environmental Sustainability, Flavonoids, Anti cancer alkaloids, Inulin Esters, Fructooligosaccharides, Galanthamine, Phytochemistry, Pharmacognosy and Phytochemistry, and Food Scienceedit
Carlina acanthifolia All. is widely used in traditional medicine due to the presence of essential oil (1-2%) in the outer part of the roots of the plant. It is mainly used for its choleretic and anti-inflammatory properties, as well as... more
Carlina acanthifolia All. is widely used in traditional medicine due to the presence of essential oil (1-2%) in the outer part of the roots of the plant. It is mainly used for its choleretic and anti-inflammatory properties, as well as for the treatment of gastrointestinal problems. We obtain the fractions by sequential extraction with different solvents (hexane, chloroform, ethyl acetate, and ethanol) from carline thistles (Carlina acanthifolia All.) roots, evaluate the phytochemical compounds and for the first time, we report here the 3D fluorescence excitation-emission spectra. High extractable contents of fatty acids, terpenes, sterols, sugars and polyphenols, flavonoids and carlina oxide were found in the different fractional extracts of Carlina acanthifolia root. Three phenolic acids were detected in the ethyl acetate and n-hexane fraction, benzoic acid, phenylacetic acid, and p-methoxymadelic acid. In addition, fatty acids, pentacyclic triterpenes and sugars have been identified, these phytocomponents are responsible for the fluorescent properties of the roots. The topographic view of the excitation-emission matrix outlines a large strong first maximum (em,1 = 570 nm for exc,1 = 470 nm) connected with the presence of vitamin E and fatty acids and a weaker narrower second one (em,2 = 465 nm for exc,2 = 360 nm), witch is due to the presence of flavonoids, phenolic acids and palmitic acid. The emission spectrum of the main maximum is rather large at the 90% level (em,1 = 60 nm) but is observed over a narrow excitation bandwidth (exm,1 = 25 nm). The Stokes shift Δ is around 100 nm over the excitation range from 430 to 560 nm. Seven elements-Ca, Fe, K, Mg, Mn, Na and Zn, were determined in Carlina acanthifolia All. as potassium has the highest content K = 32.7 ± 0.6 g kg −1 followed by Ca, Mg and Fe (8.24 ± 0.12;1.86 ± 0.03;1.25 ± 0.01 g kg −1) , in mg kg −1 are Na = 212 ± 3 , Mn = 41.9 ± 0.2 and Zn = 26.7 ± 0.3.
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The development of functional foods providing health benefits above the basic nutritional needs is of growing interest to the food industry. This research aimed to: design fresh prebiotic cheese spreads enriched with agave inulin (AI),... more
The development of functional foods providing health benefits above the basic nutritional needs is of growing interest to the food industry. This research aimed to: design fresh prebiotic cheese spreads enriched with agave inulin (AI), thyme (Thymus callieri Borbás ex Velen.) and hawthorn fruit (Crataegus monogyna Jacq.) as plant sources of biologically active compounds; observe the physicochemical and microbiological changes in the cheese during storage at 4°C for 35 days; evaluate the sensory characteristics of the new functional products. Therefore, five experimental groups of fresh cheese spreads were prepareda control; 1% AI + 0.2% thyme; 2% AI + 0.2% thyme; 1% AI + 0.4% hawthorn fruit and 2% AI + 0.4% hawthorn fruit. During the storage, pH in all experimental groups gradually decreased (reaching values between 4.17 and 4.25 on the 35 th day), which corresponded to the increasing titratable acidity (reaching values from 146.30°T to 152.51°T on the 35 th day). The application of thyme and hawthorn fruit did not reduce the total plate count (mesophilic aerobic and facultative anaerobic microorganisms) and yeasts; however, during the storage period the addition of agave inulin stimulated the growth of lactic acid bacteria in the treated samples compared to the control.
Research Interests: Food Science, Dairy Science, Cheese Making, Food and Nutrition, Food Chemistry, and 12 moreFood Microbiology, Food Science and Technology, Food Technology, Dairy Science and Technology, Dairy Nutrition, Dairy Technology &Food Technology, Dairy Processing, Food and Beverage, Cheese, Dairy Technology, Dairy Products, and Milk and Dairy Chemistry
The development of functional foods providing health benefits above the basic nutritional needs is of great interest to the food industry. This research aimed to: design functional yogurts with agave inulin and extracts from propolis,... more
The development of functional foods providing health benefits above the basic nutritional needs is of great interest to the food industry. This research aimed to: design functional yogurts with agave inulin and extracts from propolis, rose petals and Spirulina platensis; observe the physicochemical and microbiological changes during storage at 4°C for 21 days; evaluate the sensory characteristics of the new functional products. Three kinds of calcium alginate microcapsules (agave inulin + ethanolic propolis extract; agave inulin + ethanolic propolis extract + rose petals extract; agave inulin + ethanolic propolis extract + Spirulina extract) were prepared and applied in yogurts before the coagulation. During the storage, pH in all experimental groups gradually decreased (reaching values between 3.94 and 4.02 on the 21 st day), which corresponded to the increasing titratable acidity (reaching values from 94.17°T to 108.78°T on the 21 st day). The application of microcapsules did not affect the coagulation process and number of lactic acid bacteria in yogurts until the end of storage period. To the best of our knowledge, this is the first study to investigate the application of agave inulin, propolis, rose petals and S. platensis extracts in microencapsulated form in traditional Bulgarian yogurt in order to obtain a dairy product with enhanced functional properties.
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The aim of the present study was to evaluate and compare three types of lavender (Lavandula angustifolia Mill.) biomasses for their content of biologically active substances and potential application. The first one was from unprocessed... more
The aim of the present study was to evaluate and compare three types of lavender (Lavandula angustifolia Mill.) biomasses for their content of biologically active substances and potential application. The first one was from unprocessed lavender (L-UNTR22_Z) and the other two were industrial steam-distilled lavender solid residues (L-SD22_Z and L-SD22_M). Ash, protein, polyuronide content and the degree of esterification of the pectic substances in the biomass were investigated. 70% ethanolic extracts of the residues were prepared and their total polyphenol content and antioxidant activity were evaluated by four methods. Individual phenolic acids, flavonoids, polar non-volatile compounds and polar volatile compounds were also determined by chromatographic analyses. The highest degree of esterification (83.9±0.5%) and protein content (8.15±1.6%) were found in L-SD22_Z extract. L-SD22_M extract demonstrated the highest polyphenolic content and antioxidant activity. Six phenolic acids (protocatehuic, syringic, p-coumaric, ferulic, salicylic, and gallic acid) and five flavonoids ((+)-catechin, (-)-epicatechin, rutin, hesperidin, and quercetin) were detected by HPLC analyses. The detail information about amino acids, sugars, organic and phenolic acids, as well as polar volatile compounds was obtained by GC-MS. The results suggested that the lavender (untreated and residual biomass) are a good source of dietary antioxidants and compounds with potent biological activity.
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Functional foods and beverages can be defined as processed products that provide health benefits beyond the basic nutritional needs and reduce the risk of diseases. The design of functional products with improved shelf-life is a new... more
Functional foods and beverages can be defined as processed products that provide health benefits beyond the basic nutritional needs and reduce the risk of diseases. The design of functional products with improved shelf-life is a new challenge for the food industry. Therefore, this research aimed to: design a functional fruit-herbal beverage; compare the preservation effect of two preservatives (propolis extract and potassium sorbate) added in the beverages; evaluate the sensory characteristics of the newly designed beverages; observe the physico-chemical and microbiological changes during storage at 4℃ for 42 d. The results demonstrated that the addition of propolis extract (0.02%) in the beverage, increased the total polyphenols, total flavonoids and antioxidant activity, compared to the control beverage and the beverage containing potassium sorbate (0.05%). The results from microbiological analyses showed that potassium sorbate and propolis extract effectively inhibited the microbial growth in the treated beverages. However, the propolis extract in a lower concentration (0.02%) was as effective as potassium sorbate in a higher concentration (0.05%) during the entire storage period. Consequently, in addition to being a functional ingredient and a food enhancer, propolis is a prospective natural preservative, which can improve the shelf-life of the food products and beverages.
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Propolis is a natural mixture of resins, wax, and pollen from plant buds and flowers, enriched with enzymes and bee saliva. It also contains various essential oils, vitamins, mineral salts, trace elements, hormones, and ferments. It has... more
Propolis is a natural mixture of resins, wax, and pollen from plant buds and flowers, enriched with enzymes and bee saliva. It also contains various essential oils, vitamins, mineral salts, trace elements, hormones, and ferments. It has been found that propolis possesses antimicrobial, antiviral, and anti-inflammatory properties. We have studied the antiviral activity of six extracts of Bulgarian propolis collected from six districts of Bulgaria. The study was conducted against structurally different viruses: human coronavirus strain OC-43 (HCoV OC-43) and human respiratory syncytial virus type 2 (HRSV-2) (enveloped RNA viruses), human herpes simplex virus type 1 (HSV-1) (enveloped DNA virus), human rhinovirus type 14 (HRV-14) (non-enveloped RNA virus) and human adenovirus type 5 (HadV-5) (non-enveloped DNA virus). The influence of the extracts on the internal replicative cycle of viruses was determined using the cytopathic effect (CPE) inhibition test. The virucidal activity, its impact on the stage of viral adsorption to the host cell, and its protective effect on healthy cells were evaluated using the final dilution method, making them the focal points of interest. The change in viral infectivity under the action of propolis extracts was compared with untreated controls, and Δlgs were determined. Most propolis samples administered during the viral replicative cycle demonstrated the strongest activity against HCoV OC-43 replication. The influence of propolis extracts on the viability of extracellular virions was expressed to a different degree in the various viruses studied, and the effect was significantly stronger in those with an envelope. Almost all extracts significantly inhibited the adsorption step of the herpes virus and, to a less extent, of the coronavirus to the host cell, and some of them applied before viral infection demonstrated a protective effect on healthy cells. Our results enlarge the knowledge about the action of propolis and could open new perspectives for its application in viral infection treatment.
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Propolis (bee glue), a valuable biological mixture produced by European honey bees (Apis mellifera L.), is widely used as a remedy in traditional and alternative medicine, as an effective food biopreservative and as a nutritional value... more
Propolis (bee glue), a valuable biological mixture produced by European honey bees (Apis mellifera L.), is widely used as a remedy in traditional and alternative medicine, as an effective food biopreservative and as a nutritional value enhancer. The present study aimed to investigate eighty propolis samples collected from all twenty-eight districts of Bulgaria in the period of 2020-2022 in order to determine their physicochemical properties as well as their antioxidant and antimicrobial potential. The raw propolis samples exhibited brown or green colour depending on the climatic zone from which they are collected and pH values from 4.82 to 5.87, while the moisture content ranged between 0.98% and 2.97%. The total phenolics content (TPC) and total flavonoids content (TFC) varied from 63.14 mg GAE/g to 737.27 mg GAE/g, and from 29.22 mg QE/g to 234.17 mg QE/g, respectively. The propolis samples demonstrated significant antioxidant potential determined by DPPH and FRAP methods, from 18.56 mM TE/g to 1598.66 mM TE/g and from 82.28 mM TE/g to 1208.81 mM TE/g, respectively, whose values showed a positive correlation (r 2) with the TPC and TFC. The results from the antimicrobial screening revealed that the methanolic propolis extracts in concentration of 20 mg/ml exhibited the highest inhibitory effect on the Gram-positive bacteria such as Micrococcus luteus 2YC-YT, Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 25923, Listeria monocytogenes NBIMCC 8632 and Listeria innocua ATCC 33090.
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It is known that plants from the Carlina genus possessed many biological activity due to the bioactive compounds. The current study investigates the phytochemical constituents and antioxidant potential of the different vegetal parts of... more
It is known that plants from the Carlina genus possessed many biological activity due to the bioactive compounds. The current study investigates the phytochemical constituents and antioxidant potential of the different vegetal parts of Carlina vulgaris L., Carlina acanthifolia All. and Carlina corymbosa L. The samples (roots and aerial part) were collected from Bulgaria (Golo Bardo and Vlahina mountains). Total phenols, flavonoids, individual phenolic compounds, triterpenes, phytosterols, carlina oxide, fructans, and individual sugars were determined. Antioxidant potential was evaluated using four methods. The highest total phenolic content was
found in ethanol extract from C. acantifololia All. roots. Three phenolic acids (chlorogenic acid, ferulic acid, and salicylic acid), three flavonoids (rutin, hesperidin, and quercetin), and triterpenes (lupeol and betulin) were detected in all samples (mainly in roots). However, p-coumaric acid
and ursolic acid were detected only in C. vulgaris, while carlina oxide was found only in C. acantifololia All. roots. The result showed that the roots of C. acanthifolia All. were characterized by appreciable amounts of total fructans (20 g/100 g dry weight), while inulin represented 18-12 g/100 g of dry weight. Sugars were found in all plant materials. The current study provides data about the chemical composition of extracts obtained from three members of the Carlina genus and their use as a source of antioxidants, phenolic compounds, carlina oxide, and inulin-type prebiotics.
found in ethanol extract from C. acantifololia All. roots. Three phenolic acids (chlorogenic acid, ferulic acid, and salicylic acid), three flavonoids (rutin, hesperidin, and quercetin), and triterpenes (lupeol and betulin) were detected in all samples (mainly in roots). However, p-coumaric acid
and ursolic acid were detected only in C. vulgaris, while carlina oxide was found only in C. acantifololia All. roots. The result showed that the roots of C. acanthifolia All. were characterized by appreciable amounts of total fructans (20 g/100 g dry weight), while inulin represented 18-12 g/100 g of dry weight. Sugars were found in all plant materials. The current study provides data about the chemical composition of extracts obtained from three members of the Carlina genus and their use as a source of antioxidants, phenolic compounds, carlina oxide, and inulin-type prebiotics.
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Mentioned for the first time in the Materia medica by Pedanios Dioscorides, Sideritis scardica has been well known for its prolific anti-inflammatory properties for centuries. The name derives from the Greek word "sideros", meaning iron.... more
Mentioned for the first time in the Materia medica by Pedanios Dioscorides, Sideritis scardica has been well known for its prolific anti-inflammatory properties for centuries. The name derives from the Greek word "sideros", meaning iron. Ancient soldiers used the plant to help the healing process of cut wounds caused by iron weapons. The European Medical Agency Committee on Herbal Medicinal Products points to its traditional use for the relief of cough, associated with cold and gastrointestinal disorders. 1 Other described biological activities of the herb include anti-glioma, cytotoxic, antimicrobial, and antirheumatic. 2-5 Belonging to the Lamiaceae Family, Sideritis scardica has become more popular outside the Balkan Peninsula in the last decades. Different studies have confirmed its positive effect on cognitive and neurodegenerative diseases. 6-8 The phytochemical profile of the plant reveals many polyphenolic compoundsphenylethanoid glycosides, acetylated and nonacetylated flavonoids, and several organic phenolic acids. 2,3,9,10 With this composition, preparations from Sideritis scardica and other herbs belonging to the same genus in the Mediterranean display prominent antioxidant activity. Oxidative stress has long been linked with neurodegenerative processes, whether as a cause or part of a pathological cascade induced by other factors.
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Research Interests: Engineering, Technology, Flavonoids, Biological Sciences, Immersion, and 13 moreGene transfer techniques, Genetic transformation, Absorption, High Performance Liquid Chromatography, SAGE, High Pressure Liquid Chromatography, Phenols, Salvia, Agrobacterium, Agrobacterium-mediated transformation, Ion-exchange Resins, Phenolic Acid, and Hairy roots
Burdock (Arctium lappa L.) roots were used as a medicinal plant or vegetable worldwide. The research aimed to obtain different fractions by sequential extraction (hexane, chloroform, ethyl acetate water) of burdock roots and to evaluate... more
Burdock (Arctium lappa L.) roots were used as a medicinal plant or vegetable worldwide. The research aimed to obtain different fractions by sequential extraction (hexane, chloroform, ethyl acetate water) of burdock roots and to evaluate phytochemical compounds in them. Antioxidant and antimicrobial properties of nonpolar fractions were evaluated. Ethyl acetate fraction contained the highest total phenolics, total flavonoids, and derivatives of caffeic acids. Phenolic acids (mainly chlorogenic, caffeic acid, and p-coumaric acids) were detected only in the ethyl acetate fraction, while in the hexane fraction was found only triterpenes. Due to the high polyphenol content, the ethyl acetate fraction demonstrated the highest antioxidant activity. Three fractions revealed antimicrobial activity against Salmonella sp., Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Proteus vulgaris, Staphylococcus aureus, Bacillus cereus, and Candida albicans. The lowest minimum inhibitory concentration (>1 mg/ml) showed an ethyl acetate fraction against Pseudomonas aeruginosa and Bacillus cereus. From the water fraction was isolated inulin-type fructan with a degree of polymerization 20-24 with promising functional properties. This study showed the potential application of burdock root fractions as a rich source of phytochemicals with antimicrobial, antioxidant activities, and potential prebiotic effect due to the 7 g/100 g inulin content in them.
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The task of this study was to perform the "green" synthesis of lactose octaacetate through microwave irradiation and to establish their biological activities. Lactose ester was prepared after microwave-assisted esterification of lactose... more
The task of this study was to perform the "green" synthesis of lactose octaacetate through microwave irradiation and to establish their biological activities. Lactose ester was prepared after microwave-assisted esterification of lactose with acetic anhydride (yield 85-90 %). Lactose octaacetate was characterized by a high degree of acetylation (DS 3.2-3.7). The lactose esters' structure was elucidated by infrared spectroscopy and nuclear magnetic resonance spectroscopy. Lactose octaacetate showed better antifungal activities than antibacterial activities. It possessed slight to moderate antifungal activities against Aspergillus niger ATCC 1015, Penicillium sp., Rhizopus sp., Fusarium moniliforme ATCC 38932. Lactose acetates demonstrated low cytotoxicity against three cell lines: Madin-Darby bovine kidney (MDBK) cells, human epithelial type 2 (HEp-2), and Madin-Darby canine kidney (MDCK) cells. This is the first report for antiviral activity of lactose acetates against herpes simplex virus type 1 (HSV-1), influenza virus A/Panama/2007/99/H3N2-(IAV/H3N2), PV-1 and Coxsackievirus B1. It was found that this compound showed activity with SI = 2.4 only against PV-1, but against HSV-1, IAV/H3N2, and Coxsackievirus B1 was inactive. The current study demonstrated the applications of lactose acetates as antimicrobial and antiviral substances in food, pharmaceutical, agricultural and cosmetic preparations.
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In the present work, ice cream mixtures with 5%, 10% and 15% lingonberry extract were studied. The lingonberry (Vaccinium vitis-idaea L.) is a source of anthocyanins and flavonoids, which are the bioactive components with good antioxidant... more
In the present work, ice cream mixtures with 5%, 10% and 15% lingonberry extract were studied. The lingonberry (Vaccinium vitis-idaea L.) is a source of anthocyanins and flavonoids, which are the bioactive components with good antioxidant properties. There was a significant increase in antioxidant activity (p<0.05) from 133.3 ± 5.6 mM TE/100 g to 249.8 ± 8.3 mM TE/100 g (ABTS method) with increasing the concentration of the extract from 5% to 15%, respectively. Significant changes (p<0.05) in the acidity and dry matter of the samples with lingonberry extract were recorded. After 30 days of storage, a decrease in the antioxidant properties (p<0.05) of the ice cream samples was observed but higher values (mM TE/100 g) were maintained compared to the sample without extract. The color characteristics of the samples were also influenced by the concentration of the extract used. During storage, the highest stability of the colorimetric index a* (red component) was established, which indicates relative color stability during storage.
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Propolis is a complex honey bee product known for its antioxidant potential and antimicrobial activity, widely used as a food biopreservative and food additive. The object of the current research was to investigate the effects of... more
Propolis is a complex honey bee product known for its antioxidant potential and antimicrobial activity, widely used as a food biopreservative and food additive. The object of the current research was to investigate the effects of carboxymethyl cellulose (CMC) edible coatings applied alone and in combination with a propolis extract on the quality parameters and storage life of fresh blueberries during refrigerated storage for 20 days. For this purpose, three experimental groups were prepared: blueberries without coating (control group), blueberries with 1%CMC coatings and blueberries with 1% CMC coatings+1% propolis extract (CMC+P). During the storage, the physicochemical and microbiological parameters of the experimental groups were evaluated. The use of CMC and CMC+P coatings reduced the weight loss by 1.13% and 1.67% in comparison with the control group on the 20-th day of storage. A significant decrease in decay percentage was found, which was in the great extent in the CMC+P coated fruit compared to the CMC coatings and the control fruit. The CMC and CMC+P edible coatings did not affect the TSS levels, the decreasing TA and increasing pH values. The application of CMC and CMC+P coatings did not cause a protective effect on the lowering values of total phenolic and anthocyanin contents in both treatments, but exhibited a positive influence on the antioxidant activity in CONTACT Yulian Dimitrov Tumbarski
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Bilberries (Vaccinium myrtillus L.) belong to the Ericaceae family and have been traditionally used in folk medicine for centuries because of their high content of polyphenolic compounds. Berry polyphenols exhibit strong antioxidant... more
Bilberries (Vaccinium myrtillus L.) belong to the Ericaceae family and have been traditionally used in folk medicine for centuries because of their high content of polyphenolic compounds. Berry polyphenols exhibit strong antioxidant properties that could have preventive and therapeutic effects for cardiovascular disease, neurodegenerative disorders, cancer, diabetes, osteoporosis, obesity. More recently, scientific interest in the leaf composition and beneficial properties has been growing, documenting that berry leaves can be considered an alternative source of bioactive substances. The main compounds in berry leaves are similar to those in berry fruits, i.e., phenolic acids, flavonols, proanthocyanidins. The leaves are one of the richest sources of chlorogenic acid. The aim of the current research was to investigate the intrapolulation variations of polyphenolic compounds in a bilberry (Vaccinium myrtillus L.) habitat in order to select the most productive plant individuals for introduction in vitro. The total polyphenols, total flavonoid content, total proanthocyanidines and antioxidant capacity were estimated by Folin–Ciocalteu’s method, aluminium nitrate method, n-butanol-HCl assay and DPPH, respectively.
The total polyphenol content of bilberry was 52.37 ± 8.62 mg GAE g−1 DW with coefficient of variation (CV%) 16.45%. The radical scavenging activity of the bilberry population defined by DPPH assay was 477.18±111.32 mmol TE g−1 DW with CV – 23.33%. HPLC analyses revealed that the dominant phenolic acid of the bilberry population was chlorogenic acid (17.10 ± 3.21 mg g−1 DW). The results obtained revealed that the analyzed population of bilberry possessed significant intrapopulation variations in respect of the quantity of investigated secondary metabolites.
The total polyphenol content of bilberry was 52.37 ± 8.62 mg GAE g−1 DW with coefficient of variation (CV%) 16.45%. The radical scavenging activity of the bilberry population defined by DPPH assay was 477.18±111.32 mmol TE g−1 DW with CV – 23.33%. HPLC analyses revealed that the dominant phenolic acid of the bilberry population was chlorogenic acid (17.10 ± 3.21 mg g−1 DW). The results obtained revealed that the analyzed population of bilberry possessed significant intrapopulation variations in respect of the quantity of investigated secondary metabolites.
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The aim of this study was profiling of primary metabolites of five Bulgarian Fumaria species (F. officinalis L., F. thuretii Boiss., F. kralikii Jord., F. rostellata Knaf. and F. schrammii Velen.) by GC-MS analyses. In polar fractions ten... more
The aim of this study was profiling of primary metabolites of five Bulgarian Fumaria species (F. officinalis L., F. thuretii Boiss., F. kralikii Jord., F. rostellata Knaf. and F. schrammii Velen.) by GC-MS analyses. In polar fractions ten carbohydrates, one polyol, ten amino acids and six organic acids were identified. Apolar (lipid) fractions showed the presence of four free fatty acids, two esters of fatty acids with glycerol and two fatty alcohols. Sucrose and fructose were in the highest relative concentrations of identified carbohydrates. Citric acid was the dominant organic acid in polar fractions of five Fumaria species. Predominant compounds in lipid fractions were palmitic acid and 1-stearoyl-glycerol. Principal component analysis (PCA) of GC-MS data of polar and apolar fractions of five Bulgarian Fumaria species differentiates them in two groups (F. officinalis and F. thuretii; F. rostellata and F. schrammii, respectively), while F. kralikii had phythochemical similarity w...
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Citation: Vrancheva, R.; Ivanov, I.; Dincheva, I.; Badjakov, I.; Pavlov, A. Plants 2021, 10, 94. https://doi.
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The aim of the current study was to evaluate the natural pigments (chlorophylls, carotenoids and antho-cyanins), phenolic compounds and antioxidant activity of water and 95% ethanol extracts from five edible flowers-snapdragon... more
The aim of the current study was to evaluate the natural pigments (chlorophylls, carotenoids and antho-cyanins), phenolic compounds and antioxidant activity of water and 95% ethanol extracts from five edible flowers-snapdragon (Antirrhinum majus), carnation (Dianthus plumarius), garden geranium (Pelargonium hortorum), petunia (Petunia integrifolia) and dahlia (Dahlia decorative). It was found that water extracts gave higher extractive yields. The highest carotenoids and total anthocyanins content were detected in snapdragon and dahlia flowers. The total phenolic content dominated in water extracts of petunia, garden geranium, carnation and snapdragon-above 30 mg GAE/g of dry extract. Sinapic acid was detected in all edible flowers. Gallic, caffeic, chlorogenic, p-coumaric, rosmarinic, sinapic and ferulic acid were detected only in carnation. Antioxidant activity was the highest in ethanol extracts of petunia, garden geranium, carnation by FRAP method. The current study demonstrated the future application of edible flower extracts as a source of antioxidants for culinary purposes.
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The aim of this study was GC-MS analysis of alkaloid profiles of different aerial parts (leaves, stems and flowers) of three Corydalis species, naturally grown in Bulgaria (Corydalis solida (L.) Clairv., Corydalis marschalliana (Willd.)... more
The aim of this study was GC-MS analysis of alkaloid profiles of different aerial parts (leaves, stems and flowers) of three Corydalis species, naturally grown in Bulgaria (Corydalis solida (L.) Clairv., Corydalis marschalliana (Willd.) Pers. and Corydalis bulbosa (L.) DC.), as well as analysis of the acetylcholinesterase inhibitory activity of obtained alkaloid extracts. Thirteen isoquinoline alkaloids were identified, as the principal ones were: protopines (protopine, allocryptopine and corycavidine); aporphines (corydine, bulbocapnine and nantenine); benzylisoquinolines (N-methyllaurotetanine); protoberberines (stylopine and canadine); spirobenzylisoquinolines (parfumine, fumarophycine and bicuculline); and phenanthrenes (thalicthuberine). Investigated alkaloid extracts showed significant acetylcholinesterase (AChE) inhibitory activity in comparison to galanthamine (IC 50 0.31 mg/mL), as the highest activity possessed leave extracts of Corydalis solida and C. marschalliana (IC 50 0.36 mg extract /mL).
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Plants belonging to the monocotyledonous Amaryllidaceae family include about 1100 species divided among 75 genera. They are well known as medicinal and ornamental plants, producing pharmaceutically important alkaloids, the most... more
Plants belonging to the monocotyledonous Amaryllidaceae family include about 1100 species divided among 75 genera. They are well known as medicinal and ornamental plants, producing pharmaceutically important alkaloids, the most intensively investigated of which are galanthamine and lycorine. Amaryllidaceae alkaloids possess various biological activities, the most important one being their anti-acetylcholinesterase activity, used for the treatment of Alzheimer's disease. Due to increased demand for Amaryllidaceae alkaloids (mainly galanthamine) and the limited availability of plant sources, in vitro culture technology has attracted the attention of researchers as a prospective alternative for their sustainable production. Plant in vitro systems have been extensively used for continuous, sustainable, and economically viable production of bioactive plant secondary metabolites. Over the past two decades, a significant success has been demonstrated in the development of in vitro systems synthesizing Amaryllidaceae alkaloids. The present review discusses the state of the art of in vitro Amaryllidaceae alkaloids production, summarizing recently documented plant in vitro systems producing them, as well as the authors' point of view on the development of biotechnological production processes with a focus on the future prospects of in vitro culture technology for the commercial production of these valuable alkaloids.
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Dandelion (Taraxacum officinale L. Weber ex F.H. Wigg.) roots were traditionally used in folk medicine worldwide due to its antidiabetic, choleretic, antirheumatic and diuretic properties. The aim of the current study was to determinate... more
Dandelion (Taraxacum officinale L. Weber ex F.H. Wigg.) roots were traditionally used in folk medicine worldwide due
to its antidiabetic, choleretic, antirheumatic and diuretic properties. The aim of the current study was to determinate
the biologically active substances in 95% ethanol and subsequent water extracts from dandelion roots and to evaluate
their antioxidant activities. The carbohydrate composition was analyzed by the resorcinol assay, TLC and HPLC-RID
methods. The total phenolic contents (TPC), total flavonoids (TF) and total dihydroxycinnamic derivatives contents
were determined by Folin–Ciocalteau method, aluminium chloride colorimetric assay and Arnow’s reagent,
respectively. In vitro antioxidant activities of the extracts were estimated using ferric-reducing/antioxidant power
(FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assays. In spring harvested dandelion roots the
total fructan content were established to be in range 17-19 % dw. The low molecular carbohydrate fraction presented
by glucose, fructose, sucrose, 1-kestose and nystose dominated in 95 % ethanol extracts. The subsequent water extracts
demonstrated the highest inulin content (12% dw), while TPC, TF and total dihydroxycinnamic derivatives contents
were reported to be 9.2 mg GAE/g, 1.7 mg QE/g and 13.7 mg chlorogenic acid derivates/g dw, respectively. These
extracts showed the highest antioxidant activity for both the DPPH (82.1 mM TE/g) and FRAP (52.9 mg mM TE/g)
assays. Therefore, the subsequent water extracts possessed the highest antioxidant capacity, which positively correlated
with the phenolic content. The results of current investigation demonstrate that dandelion root is a valuable source of
dietary fibers and natural antioxidants and could be successfully used in foods with the potential to improve digestion
and prevent from oxidative stress related diseases.
to its antidiabetic, choleretic, antirheumatic and diuretic properties. The aim of the current study was to determinate
the biologically active substances in 95% ethanol and subsequent water extracts from dandelion roots and to evaluate
their antioxidant activities. The carbohydrate composition was analyzed by the resorcinol assay, TLC and HPLC-RID
methods. The total phenolic contents (TPC), total flavonoids (TF) and total dihydroxycinnamic derivatives contents
were determined by Folin–Ciocalteau method, aluminium chloride colorimetric assay and Arnow’s reagent,
respectively. In vitro antioxidant activities of the extracts were estimated using ferric-reducing/antioxidant power
(FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assays. In spring harvested dandelion roots the
total fructan content were established to be in range 17-19 % dw. The low molecular carbohydrate fraction presented
by glucose, fructose, sucrose, 1-kestose and nystose dominated in 95 % ethanol extracts. The subsequent water extracts
demonstrated the highest inulin content (12% dw), while TPC, TF and total dihydroxycinnamic derivatives contents
were reported to be 9.2 mg GAE/g, 1.7 mg QE/g and 13.7 mg chlorogenic acid derivates/g dw, respectively. These
extracts showed the highest antioxidant activity for both the DPPH (82.1 mM TE/g) and FRAP (52.9 mg mM TE/g)
assays. Therefore, the subsequent water extracts possessed the highest antioxidant capacity, which positively correlated
with the phenolic content. The results of current investigation demonstrate that dandelion root is a valuable source of
dietary fibers and natural antioxidants and could be successfully used in foods with the potential to improve digestion
and prevent from oxidative stress related diseases.
Research Interests:
Burdock (Arctium lappa L.) roots are traditionally used in folk medicine as diuretic and curing rheumatism, gastritis, gout, throat pain, arthritis and rashes. These pharmacological properties are due to many bioactive compounds such as... more
Burdock (Arctium lappa L.) roots are traditionally used in folk medicine as diuretic and curing rheumatism, gastritis, gout, throat pain, arthritis and rashes. These pharmacological properties are due to many bioactive
compounds such as flavonoids and fructooligosaccharides. Nowadays, the application of “green” methods for extraction of natural compounds gains more and more attention. The object of the current research was to
determine inulin and sugars content, phenolic content and antioxidant potential in 70% ethanol and water extracts obtained by two “green“ extraction methods, namely pressure-liquid extraction and ultrasound-assisted techniques. The content of total fructans, as well as inulin and sugars were analyzed by spectrophotometric resorcinol-thiourea method and high-performance liquid chromatography with refractive index detection. Total phenols and flavonoids were determined by Folin-Chiocalteu and Al(NO3
)3
reagents. Antioxidant activity
was evaluated by four reliable methods (DPPH, ABTS, FRAP and CUPRAC). The established inulin content
varied from 0.27 to 4.0 g/100 g dw in prevalence of the ultrasound-assisted extract obtained with water. Additionally, the established phenolic compounds content (from 10.35 to 18.16 mg gallic acid equivalent (GAE)/g dw) and antioxidant activities demonstrated the burdock roots as potential source phytonutrients with health
beneficial properties.
compounds such as flavonoids and fructooligosaccharides. Nowadays, the application of “green” methods for extraction of natural compounds gains more and more attention. The object of the current research was to
determine inulin and sugars content, phenolic content and antioxidant potential in 70% ethanol and water extracts obtained by two “green“ extraction methods, namely pressure-liquid extraction and ultrasound-assisted techniques. The content of total fructans, as well as inulin and sugars were analyzed by spectrophotometric resorcinol-thiourea method and high-performance liquid chromatography with refractive index detection. Total phenols and flavonoids were determined by Folin-Chiocalteu and Al(NO3
)3
reagents. Antioxidant activity
was evaluated by four reliable methods (DPPH, ABTS, FRAP and CUPRAC). The established inulin content
varied from 0.27 to 4.0 g/100 g dw in prevalence of the ultrasound-assisted extract obtained with water. Additionally, the established phenolic compounds content (from 10.35 to 18.16 mg gallic acid equivalent (GAE)/g dw) and antioxidant activities demonstrated the burdock roots as potential source phytonutrients with health
beneficial properties.
Research Interests:
The aim of the current research is to investigate the effects of edible coatings based on celery pectin singly and in combination with a bacteriocin of Bacillus methylotrophicus BM47 on the quality and storage life of fresh blackberries... more
The aim of the current research is to investigate the effects of edible coatings based on celery pectin singly and in combination with a bacteriocin of Bacillus methylotrophicus BM47 on the quality and storage life of fresh blackberries under refrigeration conditions. In this study three experimental groups were prepared: uncoated blackberries as a control, blackberries with 1% pectin coatings and blackberries with 1% pectin coatings+bacteriocin of B. methylotrophicus BM47. During the storage at 4°C and 75% RH for 16 days, the weight loss, decay percentage, total soluble solids (TSS), titratable acidity (TA), pH, organic acids, sugars, total phenolic content, total anthocyanins and antioxidant activity were analyzed.
The results showed that the application of pectin and pectin+bacteriocin coatings led to a reduction in weight loss with 6.3% and 6.7% compared to the control fruit on the 16-th day of storage. A decrease in decay percentage was also noticed, which was most pronounced in the pectin+bacteriocin coated fruit compared to the pectin coatings and control. The pectin and pectin+bacteriocin coatings reduced TSS levels with 0.4% and 0.6%, respectively compared to the control on the 16-th day of the storage, but did not affect TA and pH values. The pectin and pectin+bacteriocin coatings had no effect on decreasing total phenolic and anthocyanin contents or the concentration of sugars (glucose and fructose) in both treatments and the control fruit. The pectin and pectin+bacteriocin edible coatings exhibited a protective effect on the ascorbic acid content, maintaining concentrations of 57.5 mg/100 g of fw and 58.8 mg/100 g of fw (day 16), which were close to the initial values. The pectin and pectin+bacteriocin treatments had also a positive impact on antioxidant activity in the coated blackberries. Both edible coatings effectively inhibited its decrease with the prolongation of the storage time and kept antioxidant levels of 231.8 TE/100 g of fw and 232.4 TE/100 g of fw (day 16) that were close to the initial values.
The results showed that the application of pectin and pectin+bacteriocin coatings led to a reduction in weight loss with 6.3% and 6.7% compared to the control fruit on the 16-th day of storage. A decrease in decay percentage was also noticed, which was most pronounced in the pectin+bacteriocin coated fruit compared to the pectin coatings and control. The pectin and pectin+bacteriocin coatings reduced TSS levels with 0.4% and 0.6%, respectively compared to the control on the 16-th day of the storage, but did not affect TA and pH values. The pectin and pectin+bacteriocin coatings had no effect on decreasing total phenolic and anthocyanin contents or the concentration of sugars (glucose and fructose) in both treatments and the control fruit. The pectin and pectin+bacteriocin edible coatings exhibited a protective effect on the ascorbic acid content, maintaining concentrations of 57.5 mg/100 g of fw and 58.8 mg/100 g of fw (day 16), which were close to the initial values. The pectin and pectin+bacteriocin treatments had also a positive impact on antioxidant activity in the coated blackberries. Both edible coatings effectively inhibited its decrease with the prolongation of the storage time and kept antioxidant levels of 231.8 TE/100 g of fw and 232.4 TE/100 g of fw (day 16) that were close to the initial values.
The aim of the current research is to investigate the effects of edible coatings based on celery pectin singly and in combination with a bacteriocin of Bacillus methylotrophicus BM47 on the quality and storage life of fresh blackberries... more
The aim of the current research is to investigate the effects of edible coatings based on celery pectin singly and in combination with a bacteriocin of Bacillus methylotrophicus BM47 on the quality and storage life of fresh blackberries under refrigeration conditions. In this study three experimental groups were prepared: uncoated blackberries as a control, blackberries with 1% pectin coatings and blackberries with 1% pectin coatings+bacteriocin of B. methylotrophicus BM47. During the storage at 4°C and 75% RH for 16 days, the weight loss, decay percentage, total soluble solids (TSS), titratable acidity (TA), pH, organic acids, sugars, total phenolic content, total anthocyanins and antioxidant activity were analyzed.
Research Interests: Food Science, Thin Films and Coatings, Food Chemistry, Food Microbiology, Food Science and Technology, and 10 moreFood Security, Surface Coatings, Blackberry, Industrial Microbiology, Food Microbilogy,medical Bacteriology, Biopreservation, Surface and Coatings Technology, Natural Biopreservatives, Food sciences and nutrition, Bacteriocin Producing Microroganisms, and Edible Coating
Changes in phytochemical compounds and antioxidant potential of fresh, frozen, and processed figs (Ficus carica L.) Abstract The aim of the present work was to evaluate some phytochemical compounds in fresh, frozen, and processed... more
Changes in phytochemical compounds and antioxidant potential of fresh, frozen, and processed figs (Ficus carica L.) Abstract The aim of the present work was to evaluate some phytochemical compounds in fresh, frozen, and processed yellow-coloured figs (Ficus carica L.). The moisture content, ash, titrable acidity, total chlorophylls, total carotenoids, total phenols, total flavonoids, total anthocyanins, as well as carbohydrates (fructose, glucose, and sucrose) were evaluated. In addition, the antioxidant capacities of fresh, frozen, and processed figs (jam) were determined by DPPH and FRAP assays. The highest values of bioactive compounds and antioxidant activity were found in fresh fruits, while in frozen fruits their levels decreased significantly. The preparation of fig jam was a better approach for preserving some bioactive compounds, especially carotenoids and phenolic compounds. After four months of storage at-18°C, it was observed that there were significant losses in the antioxidant potential, decrease in sucrose content, as well as total phenols, total flavonoids, and total anthocyanins values. In spite of the reduction in some valuable compounds, jam processing retained good amount of them during storage in comparison with freezing storage.
Research Interests:
Culinary herbs were known and applied from ancient times in food production and for culinary purposes, as flavor enhancers and food preservation, because of the bioactive substances with antimicrobial and antioxidant properties.... more
Culinary herbs were known and applied from ancient times in food production and for culinary purposes, as flavor enhancers and food preservation, because of the bioactive substances with antimicrobial and antioxidant properties. Therefore, they can successfully use as sources of natural antioxidants that improve consumer health and the nutritional value of foodstuffs. The aim of the current study was to evaluate the fructan content and antioxidant activity in leaves of four culinary herbs: tarragon (Artemisia dracunculos L.), chives (Allium schoenoprasum L.), wild garlic or ramson (Allium ursinum L.) and samardala (Nectaroscordum siculum Lindl.) used in Bulgarian traditional cuisine. The content of total chlorophylls, total carotenoids, phenols, derivatives of caffeic acids (DCA), flavonoids and fructans in culinary herb extracts were analysed. The antioxidant activity of the water extracts was evaluated by two reliable methods (DPPH and FRAP). It was found that chives dry leaves contained the highest total chlorophylls (2255 μg/g dw). Total carotenoids and DCA were detected only in tarragon leaves, where, in addition, the total phenol content was the highest (25 mg GAE/g dw). It possessed the highest antioxidant potential probably due to the high polyphenolic content. However, the leaves of samardala showed the highest total flavonoids content (7.87 mg QE/ g dw), while chives possessed the highest total fructans (5.66 g/100 g dw). This is the first report that evaluated chives, wild garlic and tarragon leaves as natural sources of prebiotics from fructan family, especially 1-kestose found in them. The current study demonstrated the antioxidant potential and prebiotics content in four culinary herbs used as spices in nutritional habitats of Bulgarian consumers.
Research Interests:
The study aimed at determination and analysis of total acidity (pH), titratable acidity, total polyphenols content, total anthocyanins content and DPPH antioxidant activity (radical scavenging activity) of Rubus idaeus L cv. Rubin juice... more
The study aimed at determination and analysis of total acidity (pH), titratable acidity, total polyphenols content, total anthocyanins content and DPPH antioxidant activity (radical scavenging activity) of Rubus idaeus L cv. Rubin juice obtained from fruits of a variety grown in different geographical areas and altitudes in Bulgaria. A systematic approach and critical analysis of the available scientific periodicals were applied; DPPH method was used for determining the antioxidant activity (radical trapping activity). The value of pH index ranges from 2.99±0.03 to 2.75±0.03. The lowest level of common phenols 251.73 ± 0.20 mg GAE/100 mL was observed in raspberry from Banya town. Total anthocyanins were within the range of 13.79 ± 0.13 mg/100 mL. (Dolna Banya town-643 m.) to 86.89 ± 0.06 mg/100 mL (Dobrila hut-1804 m.). Antioxidant activity (DPPH) has values from 37287 ± 030 mmol TE/100 ml (Uzundjovo village) to 2240.20 ± 19.10 mmol TE/100 ml (Dobrila hut-1804 m.). The antioxidant activity of raspberry juice obtained from R. idaeus cv. Rubin mainly depends on the total anthocyanins content (r 2 = 0.71). The antioxidant activity significantly increases with the increase in altitude, i.e. they have a significant correlation (r 2 = 0.81).
Research Interests:
Worldwide, studies of Nectaroscordum siculum ssp. bulgaricum (Janka) Stearn have been focused mainly on the botanical and taxonomic characteristics of the species resulting in scanty data about its polyphenol profile and biological... more
Worldwide, studies of Nectaroscordum siculum ssp. bulgaricum (Janka) Stearn have been focused mainly on the botanical and taxonomic characteristics of the species resulting in scanty data about its polyphenol profile and biological activity. Therefore, the aim of the present work was to analyse and compare the polyphenol substances and antioxidant activity of four wild populations of N. siculum growing in Bulgaria. The total phenolic content of 70% ethanolic extracts of the analysed populations ranged between 15.62 ± 0.22 and 43.50 ± 0.50 mg Gallic acid equivalent (GAE) per g dry weight (DW) (mg GAE/g DW). The total flavonoid content varied between 5.66 ± 0.03 and 25.71 ± 0.17 mg quercetin equivalent (QE) per g DW (mg QE/g DW). Analysis of polyphenol profiles by High Performance Liquid Chromatography with Diode Array Detector (HPLC-DAD) revealed the domination of sinapic acid (between 3.23 ± 0.02 and 6.37 ± 0.07 mg/g DW) and hyperoside (between 4.72 ± 0.02 and 22.94 ± 0.06 mg/g DW). All the analysed populations possessed antioxidant activity, determined by four most used in vitro methods, namely DPPH, ABTS, FRAP and CUPRAC. The highest radical scavenging and reduction ability was measured for the extract of the population from Eastern Stara Planina Mts. that could be explained by the highest amount of total and individual phenolic acids and flavonoids. The present work showed that the leaves of N. siculum are a valuable source of polyphenols and could potentially find applications in different food systems to improve their health benefits.
Research Interests:
Polygonum hydropiper L. (water pepper), an important medicinal plant from the Polygonaceae family, is traditionally used in folk medicine as an anti-cancer and anti-rheumatic agent, against diarrhea, positively influencing cerebral... more
Polygonum hydropiper L. (water pepper), an important medicinal plant from the Polygonaceae family, is traditionally used in folk medicine as an anti-cancer and anti-rheumatic agent, against diarrhea, positively influencing cerebral ischemia, Parkinson’s disease, and with neuroprotective effects. The aim of the current study was to evaluate and compare the total polyphenol content and antioxidant activity of water (infusion, decoction and microwave) and alcohol (tincture) extracts of Polygonum hydropiper. The total flavonoid content, total monomeric anthocyanin content and detailed phenolic acids profile were additionally assessed. The polyphenol content was established to be in range from 5.02 ± 0.07 to 17.44 ± 0.24 mg GAE/g dw, the total flavonoids from 3766.27 ± 118.25 to 6909.66 ± 66.03 µM QЕ/g dw and total monomeric anthocyanins from 0.26 ± 0.14 to 3.17 ± 0.44 mg/l. The in vitro antioxidant activity was evaluated by four common procedures, the highest results were established for the decoction, and tincture extracts. The phenolic acids profile revealed the highest yield, in respect of total phenolic acids, in the water pepper tincture - 3243.74 µg/g dw. As a result, the consumption of P. hydropiper extracts could be recommended as a good source of biologically active substances with potential benefit effects.
Research Interests:
European cinquefoil (Potentilla reptans L.) (Rosaceae) is very common in the Central Europe and Balkan Peninsula. Since ancient times the European cinquefoil have been traditionally used in herbal medicine for treatment of tooth ache,... more
European cinquefoil (Potentilla reptans L.) (Rosaceae) is very common in the Central Europe and Balkan Peninsula. Since ancient times the European cinquefoil have been traditionally used in herbal medicine for treatment of tooth ache, ulcers and inflammation of the throat, as well as certain forms of cancer, infections due to bacteria, fungi and viruses, diarrhea, diabetes mellitus and other ailments. Most species of genus Potentilla contain hydrolysable tannins, proanthocyanidins, flavonoids and triterpenes as bioactive substances. The aim of this study was to establish the most suitable condition for extraction of biologically active substances from Potentilla reptans aerial parts. The influence of the time of the ultrasonic extraction and solvent concentration (ethanol-water) in different ratio over the extraction process was studied. The optimal conditions for the extraction of biologically active substances from European cinquefoil were as follow: 40% ethanol-water as solvent system and extraction time 45 min in ultrasonic bath with frequency 35 kHz. Under these conditions the maximum values of total polyphenols content, total proanthocyanidins and total hydrolysable tannins (60.2 mg GAE/ g dw, 93.1 mg LE/100g dw, 101.3 mg TAE /g dw) were obtained.
Research Interests:
The lavender is among the most famous and valuable industrially plant for the production of essential oil. After the production of essential oil, waste biomass present a potential valuable source of biologically active substances. In this... more
The lavender is among the most famous and valuable industrially plant for the production of essential oil. After the production of essential oil, waste biomass present a potential valuable source of biologically active substances. In this study the content of polyphenols and triterpenes in various extracts (methanol, ethanol and acetone) obtained by various extraction techniques (maceration, under reflux and ultrasound-assisted extraction) were investigated. The antimicrobial and antioxidant activity of the extracts were evaluated The highest values of total pentacyclic triterpenes were established in extract obtained by ultrasound-assisted extraction with methanol (MUS)-227.3 mg/g extract and 963.5 mg/100 g DW (14.8 mg/g extract betulinic acid, 251.5 mg/g extract oleanolic acid and 153.1 mg/g extract ursolic acid, respectively). In general, all extracts obtained by ultrasound-assisted extraction demonstrated the highest levels of total polyphenolic content and antioxidant activity. Lavender waste was evaluated as a perspective and promising alternative source of pentacyclic triterpenes with potential application in cosmetics and the pharmaceutical industry.
Research Interests:
In the current study, an acidic polysaccharide from the in vitro suspension culture of Fumaria officinalis L. was obtained by extraction with 0.8% (w/v) aqueous ammonium oxalate. The polysaccharide fraction mainly consisted of... more
In the current study, an acidic polysaccharide from the in vitro suspension culture of Fumaria officinalis L. was obtained by extraction with 0.8% (w/v) aqueous ammonium oxalate. The polysaccharide fraction mainly consisted of galacturonic acid (41.0%), followed by galactose (7.3%) and arabinose (5.6%). This suggests the presence of arabinogalactan side chains in the rhamnogalacturonan-I segment of the studied pectin, which was mainly built up by homogalacturonan segments. The pectin was evaluated as low-methyl-esterified (45.0%) with degree of acetylation 3.4%. The polymer fraction was consisted of different molecular weight populations in the range of 6–600 kDa. The high amount of 4-L-hydroxyproline (11.7% of total protein) and the specific positive reaction to Yariv’s phenylglycoside reagent indicated the presence of an arabinogalactan protein in the cell walls. The functional properties of the polysaccharide fraction were evaluated, as it possessed better water-holding capacity than oil-holding capacity. The studied pectin demonstrated significant foaming ability and promising emulsifying properties in a concentration 1%. Therefore, the isolated polysaccharide fraction could be successfully used as emulsifier and foaming agent in food products and pharmaceutical supplements.
Research Interests:
Members of the bacterial genus Bacillus are known as producers of a broad spectrum of antibiotic compounds of proteinaceous nature that possess inhibitory activity against different saprophytic and pathogenic microorganisms. In the... more
Members of the bacterial genus Bacillus are known as producers of a broad spectrum of antibiotic compounds of proteinaceous nature that possess inhibitory activity against different saprophytic and pathogenic microorganisms. In the current research, a peptide synthesized by Bacillus methylotrophicus strain BM47, previously isolated from a natural thermal spring in Bulgaria, was identified and characterized as a bacteriocin. In vitro antimi-crobial screening of the crude bacteriocin substance of B. methylotrophicus BM47 showed activity against the plant pathogenic fungi Fusarium moniliforme, Aspergillus awamori, Pen-icillium sp., Aspergillus niger and Gram-negative bacterium Pseudomonas aeruginosa. The antimicrobial activity of the crude bacteriocin substance was partially inhibited by the enzymes trypsin, Alcalase®, Savinase®, proteinase K, papain and Esperase®, while catalase was not effective. The crude bacteriocin substance was relatively pH resistant, but sensitive to the action of heat and most organic solvents and detergents tested. To obtain the active protein fractions, crude bacteriocin substance was purified by fast protein liquid chromatography (FPLC) using a strong anion exchange column. Tricine-sodium dodecyl sulfate-po-lyacrylamide gel electrophoresis analysis demonstrated that the purified bacteriocin had molecular mass of 19 578 Da. The amino acid analysis performed by high-performance liquid chromatography (HPLC) revealed that the isolated bacteriocin consisted of 17 types of amino acids, with the highest mol fraction expressed as percent of serine (29.3), valine (10.3), alanine (9.8) and tyrosine (7.1).
Research Interests:
The aim of the study was the determination and analysis of pH, content of common phenols, antioxidant activity (radical trapping activity), common anthocyanins and acidity of pomegranate (Punica granatum) and their relation to the soil... more
The aim of the study was the determination and analysis of pH, content of common phenols, antioxidant activity (radical trapping activity), common anthocyanins and acidity of pomegranate (Punica granatum) and their relation to the soil composition and altitude. Methods for systematic approach and critical analysis of the available scientific periodicals were applied. Spectrophotometric method was used for determination of adsorption with gallic acid standard; DPPH method was used for determining the antioxidant activity (radical trapping activity). It was found that the value of pH index ranges from 3.05 to 4.29. The lowest level of common phenols 67.71 ± 0.12 mg GAE/100 ml was observed in the Red Filk variety. Total anthocyanins were within the range of 0.60 ± 0.01 mg/100 ml (Red Filk) to 35.80 ± 0.65 mg/100 ml (Pink Satin). Antioxidant activity (DPPH) was: 966.13 ± 37.67 mmol TE/100 ml (Red Filk) to 2271.72 ± 26.91 mmol TE/100 ml. Titratable acidity was within the range: 0.47 ± 0.10 g/100 mL for Red Filk and up to 1.64 ± 0.10 g/100 mL for Pink Satin. It was concluded that there is a direct correlation between the antioxidant activity and the altitude at which the pomegranate is growing. There is a direct correlation between the common phenols and the antioxidant activity, excluding variety Wonderful.
Research Interests:
We report for the first time fumaric acid biosynthesis by in vitro systems of Fumaria spp. The highest amount of fumaric acid (137 mg/L) was accumulated by Fumaria officinalis L. plant cell culture, cultivated at submerged conditions in... more
We report for the first time fumaric acid biosynthesis by in vitro systems of Fumaria spp. The highest amount of fumaric acid (137 mg/L) was accumulated by Fumaria officinalis L. plant cell culture, cultivated at submerged conditions in darkness. The prospects for efficient process development were also discussed.
Research Interests:
The aim of the current study was to evaluate nutritional and antioxidant potential of commercial carob flour. The evaluation of functional properties of carob polysaccharide presented additional interest for pharmaceutical and food... more
The aim of the current study was to evaluate nutritional and antioxidant potential of commercial carob flour. The evaluation of functional properties of carob polysaccharide presented additional interest for pharmaceutical and food application of this flour. Ash, moisture, protein, carbohydrate, lipid, total phenolic and total flavonoids contents and antioxidant potential were studied. The polysaccharide from carob flour was isolated and their monosaccharide composition and functional properties as solubility, swelling, water and oil-holding capacities were also studied. Moisture content did not exceeded 7.6 %. The carob flour contained 2 % ash, 5.9 % protein, carbohydrates (85.5%), low lipids content (0.5 %), total phenols and flavonoids 8.1 mg GAE/g dw and 8.1 mg QE/g dw, respectively. Antioxidant potential of this flour were 70.4 mM TE/g dw (DPPH assay) and 84.2 mM TE/g dw (FRAP assay). The isolated polysaccharide from carob flour was characterized as galactomannan (M/G ratio 3.5). Two polysaccharide fractions were isolated with weight molecular weights 1724 kDa and 665 kDa, respectively. The carob galactomannan showed promising water solubility (84 %), higher oil-holding capacity 4.0 g oil/g sample than water-holding capacity 1.4 g water/g sample. The carob flour was evaluated as high nutritional and antioxidant food with low fat content, but rich of dietary fibers (galactomannan).
Research Interests:
The Lemon balm (Melissa officinalis L.) is an important aromatic and medicinal plant from Lamiaceae family. Its leaves and essentials oils are used in folk medicine for the treatment of fevers and colds, hyperthyroidism, headaches and... more
The Lemon balm (Melissa officinalis L.) is an important aromatic and medicinal plant from Lamiaceae family. Its leaves and essentials oils are used in folk medicine for the treatment of fevers and colds, hyperthyroidism, headaches and toothaches. Melissa officinalis is a rich source of volatile oil, flavonoid glycosides and derivatives of caffeic acid (rosmarinic acid). The aim of current study was to evaluate and compare the polyphenol content and antioxidant activity of infusions prepared from commercially available lemon balm brands on Bulgarian market. The total polyphenol content was established to be in range from 18.17 ± 0.04 to 64.17 ± 0.52 mg GAE/g dw, the total derivatives of caffeic acid from 3.80 ± 0.05 to 21.66 ± 0.10 mg CAE/g dw, caffeic acid content from 0.16 ± 0.01 to 0.97 ± 0.03 mg/g dw and rosmarinic acid between 2.4 ± 0.02 and 23.1 ± 0.5 mg/g dw, respectively. In vitro radical scavenging activity was evaluated by DPPH method (106.31 ± 9.87-553.51 ± 46.04 mM TE/g dw) and the metal reducing antioxidant potential was established by CUPRAC method (321.32 ± 14.39-1476.63 ± 11.32 mM TE/g dw). As a result the consumption of M. officinalis infusions could be recommended as a good preventive and therapeutic source of biologically active substances with potential benefit effects.
Research Interests:
The aims of the current research were to evaluate and to compare the antioxidant activity and the content of total phenolic, flavonoids and fructan content in infusions and microwave-assisted extracts from eight herbs: rosehip (Rosa... more
The aims of the current research were to evaluate and to compare the antioxidant activity and the content of total phenolic, flavonoids and fructan content in infusions and microwave-assisted extracts from eight herbs: rosehip (Rosa canina L.), peppermint (Mentha piperita L.), thyme (Thymus vulgaris L.), coltsfoot (Tussilago farfara L.), dandelion (Taraxacum officinale Web.), elecampane (Inula helenium L.), great burdock (Arctium lappa L.) and echinacea (Echinacea purpurea Moench.). The total phenolic contents, total flavonoids and antioxidant activity were evaluated by Folin-Ciocalteau, Al(NO3)3 methods and DPPH assays. The total fructans and sugars were determined by resorcinol and HPLC-RID methods. Infusion and microwave-assisted extraction (MAE) were evaluated as efficient methods for preparation of herbal drinks. The highest values of biologically active substances and antioxidant activity were found in MAE herbal extracts. Coltsfoot, thyme and great burdock extracts demonstrated the highest content of total phenolic and flavonoids. Coltsfoot and thyme extracts showed the highest antioxidant activity (334 mM TEg-1 and 287 mM TEg-1 dw, respectively). Fructans were found in coltsfoot (4.6%) and echinacea (3.9 %) leaves, in great burdock, dandelion and elecampane roots-14 %, 34% and 44% dw, respectively. Elecampane and dandelion roots were evaluated as sources of prebiotic inulin.
Research Interests:
Balabanova, T., Ivanova, M., Ivanov, I., Dimitrova, M., Dushkova, M. & Vlaseva, R. (2018). Lactic acid beverage fortifi ed with goji berry. Bulgarian Journal of Agricultural Science, 24(5), 885-890 A lactic acid beverage fortifi ed with... more
Balabanova, T., Ivanova, M., Ivanov, I., Dimitrova, M., Dushkova, M. & Vlaseva, R. (2018). Lactic acid beverage fortifi ed with goji berry. Bulgarian Journal of Agricultural Science, 24(5), 885-890 A lactic acid beverage fortifi ed with ground goji berries has been developed. The sequence of technological operations, the chemical, microbiological, organoleptic profi le and antioxidant activity of the product during cold storage have been established. No statistically signifi cant differences (ρ ≤ 0.5) characterizing the rate of the lactic acid process, acidifi cation, total active acidity and residual lactose have been found in the test samples. The results of the microbiological analysis show that the low storage temperatures have a decisive impact on the intensity of microbial growth and correlate with acid formation. The data obtained for antioxidant activity show that the metal-reducing activity of the lactic acid beverage containing goji berries is more pronounced than the radical scavenging activity indicator.
Research Interests:
Moraceae is very common in the Mediterranean region and in the countries with dry and warm climate. Since ancient times the figs have been used for human consumption, but it was only recently that their nutritive and pharmacological value... more
Moraceae is very common in the Mediterranean region and in the countries with dry and warm climate. Since ancient times the figs have been used for human consumption, but it was only recently that their nutritive and pharmacological value has been investigated. The aim of the current study was to investigate the metabolites profile of the different extracts (diethyl ether, petroleum ether, n-hexane, acetone and ethanol) from Ficus carica leaves. The highest yield of the extractable components has been obtained with n-hexane-5.0 g/100 g dw. Thirty-seven unpolar compounds have been identified by GC-MS analysis. In the investigated extracts were mainly detected the following phytochemical compounds: saturated and unsaturated fatty acids (18% of TIC)-myristic acid, palmitic acid, margaric acid, linoleic acid, α-linolenic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid; fatty alcohols (35% of TIC)-stearyl, behenyl, pentacosan-1-ol, ceryl, montanyl, melissyl alcohol and diterpenic alcohol-phytol; phytosterols (18% of TIC)-stigmasterol, β-sitosterol, lanosterol and cycloartenol; triterpenes (11% of TIC)-squalene, α-amyrin, β-amyrin, germanicol and lupeol. Phytol (32% of TIC), β-sitosterol (12% of TIC), α-linolenic acid (8% of TIC), cycloartenol (5% of TIC), lupeol (4% of TIC), α-amyrin (3% of TIC) and β-amyrin (2% of TIC) were established as the dominants compounds in Ficus carica leaves. The obtaining extracts of fig leaves were evaluated as a valuable source of high biological active lipid components for protecting the skin from environmental stress conditions and reactive oxygen species. These extracts can be potentially used for medical and natural cosmetics and caring protection against premature skin aging.
Research Interests:
A comparative investigation of n-hexane soluble compounds from aerial parts of dandelion (Taraxacum officinale Weber ex F.H. Wigg.) collected during different vegetative stages was carried out. The GC-MS analysis of the n-hexane (unpolar)... more
A comparative investigation of n-hexane soluble compounds from aerial parts of dandelion (Taraxacum officinale Weber ex F.H. Wigg.) collected during different vegetative stages was carried out. The GC-MS analysis of the n-hexane (unpolar) fraction showed the presence of 30 biologically active compounds. Phytol [14.7% of total ion current (TIC)], lupeol (14.5% of TIC), taraxasteryl acetate (11.4% of TIC), β-sitosterol (10.3% of TIC), α-amyrin (9.0% of TIC), β-amyrin (8.3% of TIC), and cycloartenol acetate (5.8% of TIC) were identified as the major components in n-hexane fraction. The unpolar fraction exhibited promising antioxidant activity-46.7 mmol Trolox equivalents/g extract (determined by 1,1-diphenyl-2-picrylhydrazyl method). This fraction demonstrated insignificant antimi-crobial activity and can be used in cosmetic and pharmaceutical industries.
Research Interests:
Rocket plant (Eruca sativa) is a green leafy vegetable with significant levels of bioactive active components. Although, this plant is known in Bulgaria, scanty data concerning chemical composition of representatives with Bulgarian origin... more
Rocket plant (Eruca sativa) is a green leafy vegetable with significant levels of bioactive active components. Although, this plant is
known in Bulgaria, scanty data concerning chemical composition of representatives with Bulgarian origin is available. The aim of this
study was to evaluate and to compare the biological potential of Italian and Bulgarian rockets in terms of their antioxidant activity, total
phenolic content and total hydroxycinnamic acid derivatives. The micro- and macro elements were evaluated as well. The highest
content of total phenolic content was detected in Bulgarian rocket – 4.45 mg gallic acid equivalent per g dry weight, while in Italian
samples dominated the total hydroxycinnamic acid derivatives – 1.52 mg chlorogenic acid equivalent per g dry weight. The antioxidant
activity was not significantly different in both samples. The presence Co and Al was reported for the first time, as in our study their
values were higher in a rocket from Italian origin (75.6 and 595 mg/kg). Italian rocket contained arsenic (0.07 mg/g) in comparison with
Bulgarian samples where it was not found. The results revealed the sample with Italian origin as a significant better source of
antioxidants with potential beneficial effects. Bulgarian rocket was evaluated with smaller amount of some metals as nickel, arsenic,
chromium, manganese, aluminum and sodium, but the concentrations of Pb (0.58 mg/kg) and Cd (0.27 mg/kg) were higher than
accepted levels by EU.
known in Bulgaria, scanty data concerning chemical composition of representatives with Bulgarian origin is available. The aim of this
study was to evaluate and to compare the biological potential of Italian and Bulgarian rockets in terms of their antioxidant activity, total
phenolic content and total hydroxycinnamic acid derivatives. The micro- and macro elements were evaluated as well. The highest
content of total phenolic content was detected in Bulgarian rocket – 4.45 mg gallic acid equivalent per g dry weight, while in Italian
samples dominated the total hydroxycinnamic acid derivatives – 1.52 mg chlorogenic acid equivalent per g dry weight. The antioxidant
activity was not significantly different in both samples. The presence Co and Al was reported for the first time, as in our study their
values were higher in a rocket from Italian origin (75.6 and 595 mg/kg). Italian rocket contained arsenic (0.07 mg/g) in comparison with
Bulgarian samples where it was not found. The results revealed the sample with Italian origin as a significant better source of
antioxidants with potential beneficial effects. Bulgarian rocket was evaluated with smaller amount of some metals as nickel, arsenic,
chromium, manganese, aluminum and sodium, but the concentrations of Pb (0.58 mg/kg) and Cd (0.27 mg/kg) were higher than
accepted levels by EU.
Research Interests:
Culinary herbs were known and applied from ancient times in food production and for culinary purposes, as flavor enhancers and food preservation, because of the bioactive substances with antimicrobial and antioxidant properties.... more
Culinary herbs were known and applied from ancient times in food production and for culinary purposes, as flavor enhancers and food preservation, because of the bioactive substances with antimicrobial and antioxidant properties. Therefore, they can successfully use as sources of natural antioxidants that improve consumer health and the nutritional value of foodstuffs. The aim of the current study was to evaluate the fructan content and antioxidant activity in leaves of four culinary herbs: tarragon (Artemisia dracunculos L.), chives (Allium schoenoprasum L.), wild garlic or ramson (Allium ursinum L.) and samardala (Nectaroscordum siculum Lindl.) used in Bulgarian traditional cuisine. The content of total chlorophylls, total carotenoids, phenols, derivatives of caffeic acids (DCA), flavonoids and fructans in culinary herb extracts were analysed. The antioxidant activity of the water extracts was evaluated by two reliable methods (DPPH and FRAP). It was found that chives dry leaves contained the highest total chlorophylls (2255 μg/g dw). Total carotenoids and DCA were detected only in tarragon leaves, where, in addition, the total phenol content was the highest (25 mg GAE/g dw). It possessed the highest antioxidant potential probably due to the high polyphenolic content. However, the leaves of samardala showed the highest total flavonoids content (7.87 mg QE/ g dw), while chives possessed the highest total fructans (5.66 g/100 g dw). This is the first report that evaluated chives, wild garlic and tarragon leaves as natural sources of prebiotics from fructan family, especially 1-kestose found in them. The current study demonstrated the antioxidant potential and prebiotics content in four culinary herbs used as spices in nutritional habitats of Bulgarian consumers.
Research Interests:
Agastache foeniculum (Pursh) Kuntze (anise hyssop) is known as a medicinal and flavoring spice plant. The aim of this research was gas chromatography-mass spectrometry (GC-MS) analysis of anise hyssop essential oil and analysis of radical... more
Agastache foeniculum (Pursh) Kuntze (anise hyssop) is known as a medicinal and flavoring spice plant. The aim of this research was gas chromatography-mass spectrometry (GC-MS) analysis of anise hyssop essential oil and analysis of radical scavenging ability, antimicrobial activity, and acetylcholinesterase inhibitory activity. Phytochemical composition of anise hyssop wastes and the aqueous extract obtained after steam distillation was investigated. Eight compounds were identified in essential oils by GC-MS analysis, as the major ones were phenylpropenoids [estragol-93.45% of total ion current (TIC), eugenol-0.15% of TIC, and methyl isoeugenol-2.48% of TIC]. In the anise hyssop wastes extract, four pentacyclic triterpenes were identified (betulin-36.1 mg/g, betulinic acid-2.4 mg/g, oleanolic acid-160.0 mg/g, and ursolic acid-6.7 mg/g extract). Rosmarinic acid (50.6 mg/g extract) and flavonoids-myricetin (0.5 mg/g), luteolin (0.9 mg/g), and apigenin (0.6 mg/g) were detected by high-performance liquid chromatography with diode-array detection analysis of aqueous extract. The anise hyssop essential oil showed strong radical scavenging ability IC 50-6.54 μl/ml. The results obtained from antimicrobial screening revealed that essential oil possessed inhibitory activity against Staphylococcus aureus ATCC 25923, Curtobacterium flaccumfaciens
Research Interests:
Consumption of the edible flowers forms new trend in human nutrition, especially in Bulgaria. Therefore, the determination of bioactive compounds content in their petals presents important tasks for their evaluation as natural source of... more
Consumption of the edible flowers forms new trend in human nutrition, especially in Bulgaria. Therefore, the determination of bioactive compounds content in their petals presents important tasks for their evaluation as natural source of antioxidants for human diet. In this study the quantity of natural pigments, total phenolic content and total flavonoids content, as well the antioxidant capacities in 95 % (v/v) ethanol, 70 % (v/v) ethanol, 80 % (v/v) methanol and distilled water extracts obtained from five edible flowers targets (Tagetes erecta L.), marigold (Calendula officinalis L.), geranium (Geranium macrorrhizum L.), bougainvillea (Bougainvillea spectabilis Willd.), Jerusalem artichoke (Helinathus tuberous L.) were invastigated. Total phenols and flavonoid quantification of the extracts was achieved by using Folin-Ciocalteau and AlCl3 reagents, respectively. Geranium 95 % ethanol extracts were evaluated as the richest source of total phenols-19.79 mg GAE/g fw, while 80% methanol extracts of Helinathus tuberous L. showed the highest values of total flavonoids content-8.89 mg QE/g fw. The highest antioxidant capacities using two methods, DPPH and FRAP assays were obtained for 95% ethanol geranium (Geranium macrorrhizum L.) extracts-242.9 and 106 mM TE/g fw, respectively. There was positive linear correlation between antioxidant activity and total phenolic content for all investigated edible flower extracts. All studied flowers could be a valuable source of antioxidants for addition to dishes or fresh consumption for preventing diets. These findings showed that the tested flowers could be considered as new sources of safe natural antioxidants and colorants for food industry.
Research Interests:
Bacteriocins are biologically active compounds of proteinaceous nature synthesized by a large number of microorganisms, including members of bacterial genus Bacillus and lactic acid bacteria (LAB). The broad antimicrobial spectrum of... more
Bacteriocins are biologically active compounds of proteinaceous nature synthesized by a large number of microorganisms, including
members of bacterial genus Bacillus and lactic acid bacteria (LAB). The broad antimicrobial spectrum of bacteriocins against various
spoilage and pathogenic microorganisms stimulated the research efforts for their investigation and potential application in different
branches of food industry as natural preservatives. The promising antimicrobial activity of bacteriocins makes them suitable for application
as biopreservatives and alternatives of chemical preservatives in dairy industry for production of fermented or non-fermented milk
products. Therefore, the aim of the present study was to evaluate the antifungal effect of a bacteriocin isolated from Bacillus
methylotrophicus strain BM47 and the possibilities for its application as a potential biopreservative of traditional Bulgarian yogurt. The
results demonstrated that the addition of a purified bacteriocin in dose of 1 AU/mL of milk led to significant reduction of the fungal spores
and mycelial growth of the indicator microorganism Penicillium sp. in the yogurt, without a change of its organoleptic properties, and
biochemical and microbiological parameters during the 4-week period of storage.
members of bacterial genus Bacillus and lactic acid bacteria (LAB). The broad antimicrobial spectrum of bacteriocins against various
spoilage and pathogenic microorganisms stimulated the research efforts for their investigation and potential application in different
branches of food industry as natural preservatives. The promising antimicrobial activity of bacteriocins makes them suitable for application
as biopreservatives and alternatives of chemical preservatives in dairy industry for production of fermented or non-fermented milk
products. Therefore, the aim of the present study was to evaluate the antifungal effect of a bacteriocin isolated from Bacillus
methylotrophicus strain BM47 and the possibilities for its application as a potential biopreservative of traditional Bulgarian yogurt. The
results demonstrated that the addition of a purified bacteriocin in dose of 1 AU/mL of milk led to significant reduction of the fungal spores
and mycelial growth of the indicator microorganism Penicillium sp. in the yogurt, without a change of its organoleptic properties, and
biochemical and microbiological parameters during the 4-week period of storage.
Research Interests:
Fragaria vesca L. (wild strawberry) belongs to the Rosaceae family. The aerial part from wild strawberry was applied in traditional medicine. Fragaria vesca are a rich source of biologically active substances like tannins,... more
Fragaria vesca L. (wild strawberry) belongs to the Rosaceae family. The aerial part from wild strawberry was applied in traditional medicine. Fragaria vesca are a rich source of biologically active substances like tannins, proanthocyanidins, flavonoids and phenolic acids. The aim of this study was to compare the value of phytochemical compounds and antioxidant activities in infusion, decoction glycerine extracts and tinctures obtained from the F. vesca leaves and flowers. The extracts were analyzed regarding their secondary metabolites content (total polyphenols, total tannins, and total proanthocyanidins) and antioxidant activities (DPPH and FRAP methods). The analysis of 50% glycerin extracts under ultrasound irradiation shown the highest level of total polyphenols (150.2 mg GAE/g dw), total tannins (65.8 mg TAE/g dw) total proanthocyanidins (193.3 mg LE/ 100g dw) and antioxidant activities – radical scavenging activity (DPPH – 1255.2 m mol TE/ g dw) and metal reducing ability (FRAP – 1129.2 mmol TE/ g dw). The results showed that the 50% glycerin extracts from leaves and flowers of Fragaria vesca are appropriate additives for the preparation of emulsion for natural cosmetic products with improved biological activity. The most suitable solvent for tincture preparation was 50% ethanol. With this solvent, the biologically active substances were best extracted (total polyphenols – 10847.3 mg GAE/ L). The influence of the storage period at room temperature on the amount of biologically active surfactants in the obtained tinctures was also monitored. The optimal shelf life for tinctures has been determinate at 12 months.
Research Interests:
The adsorption and desorption of galanthamine on Amberlite XAD-2. XAD-4 and XAD-7 resins was investigated as a part from the development of two-phase systems for galanthamine biosynthesis by Leucojum aestivum L. It was established that... more
The adsorption and desorption of galanthamine on Amberlite XAD-2. XAD-4 and XAD-7 resins was investigated as a part from the development of two-phase systems for galanthamine biosynthesis by Leucojum aestivum L. It was established that Amberlite XAD-4 possesses the highest adsorption capacity, as 1 g resin was albe to adsorb 11.5 mg galanthamine. The further desorption process was the most effective when as an eluent acidified methanol was used (with addition of 1% 0.5M HCl). In this case 91% of galanthamine adsorbed on Amberlite XAD-4 was eluted.