Sonja Gadzovska Simic

Biotechnology, Botany, Cell Biology

PhD in Cellular and Molecular Biology
16.43

Publications

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    ABSTRACT: Hypericum perforatum cell suspensions were evaluated for their growth, phenylpropanoid and naphtodianthrone productions, and antioxidant activity after treatments with polysaccharide elicitors chitin (CHI), pectin (PEC) and dextran (DEX). Polysaccharide elicitation of cell cultures showed a considerable improving effect on phenylpropanoid production (phenolics, flavonoids, flavanols and anthocyanins) during the post-elicitation period. Even that enhanced phenylpropanoid production was related to growth suppression of CHI elicited cells, PEC and DEX were presented as effective elicitors without loss of cell biomass. Phenylpropanoid accumulation in elicited cells was correlated to markedly higher enzyme activities of phenylalanine ammonia lyase and chalcone-flavanone isomerase. Cell cultures were found to respond rapidly towards the applied elicitors through an early stimulation of both naphtodiantrones, hypericin (HYP) and pseudohypericin (PHYP). The CHI was proposed as a much more prominent elicitor in stimulation of HYP and PHYP levels in cell suspensions. All tested polysaccharide elicitors stimulated non-enzymatic antioxidant properties in cell extracts indicating the potential role of phenolic compounds as effective antioxidants. With regards to the antioxidant enzymes, an up-regulation of peroxidase and catalase activities was observed in PEC and DEX elicited cells, whereas CHI did not give any stimulatory effect on enzymatic activities. These findings suggest the involvement of an efficient antioxidant defense system in the adaptive response of cells to polysaccharide elicitation. Altogether, these results indicated that H. perforatum cells elicited with polysaccharides represent a promising experimental system for enhanced production of phenylpropanoids and naphtodianthrones.
    Plant Cell Tissue and Organ Culture 09/2015; 122(3). DOI:10.1007/s11240-015-0798-z · 2.61 Impact Factor
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    ABSTRACT: Hypericum perforatum L. cell suspensions were evaluated for their growth, antioxidant activity, phenolic compound productions and xanthone profile after elicitation with Agrobacterium tumefaciens and Agrobacterium rhizogenes. Secondary metabolite production in H. perforatum elicited cells was enhanced without loss of biomass. A. tumefaciens elicited cells showed largely increased amounts of total phenolics and flavonoids, whereas total flavanol contents were slightly enhanced. The production of phenolic compounds was clearly less marked in A. rhizogenes treated cells. Antioxidant activity of elicited cells was remarkably elevated throughout the post-elicitation period. A significant correlation between antioxidant activity and phenolic production in elicited cells was found. Xanthone profile of H. perforatum cells was notably changed after bacterial elicitation. H. perforatum elicited cells yielded about 17-fold higher levels of xanthones compared to control cells. Among the twenty one detected xanthones, five of them identified as 1,3,5,6-tetrahydroxyxanthone C-prenyl isomer, toxyloxanthone, 1,3,7-trihydroxy-6-methoxy-8-prenyl xanthone, 1,3,6-trihydroxy-7-methoxy-8-prenyl xanthone and 1,3,6,7-tetrahydroxyxanthone 2-prenyl xanthone were de novo synthesized in elicited cells. Altogether, these results indicated that H. perforatum cells elicited with Agrobacterium represent promising experimental system for enhanced production of xanthones.
    Plant Growth Regulation 06/2015; 76(2). DOI:10.1007/s10725-014-9989-6 · 1.63 Impact Factor
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    ABSTRACT: Hypericum perforatum cell suspensions were evaluated for their growth, phenylpropanoid and naphtodianthrone productions, and antioxidant activity after treatments with fungal elicitors Fusarium oxysporum, Phoma exigua and Botrytis cinerea. Elicited cells displayed a reduced biomass production, a rapid stimulation of secondary metabolites production and a modification of cell redox state compared to control. Cells responded strongly towards the applied elicitors through the enhanced production of naphtodianthrones. Hypericin and pseudohypericin production was significantly increased (up to fourfold) in the early growth phase and remained stable all along the post-elicitation period. Significant increase in contents of total phenolics, total flavonoids and total anthocyanins was observed during the entire period of cultivation, while total flavanols were enhanced at the end of post-elicitation. The enzymatic activities of phenylalanine ammonia lyase and chalcone isomerase were remarkably elevated in elicited cells confirming a strong activation of phenylpropanoid/flavonoid pathways. The fingerprint profile of Fourier transform infrared spectroscopy spectra from the cell walls showed a little variation in lignin accumulation between elicited and control samples. With regards to the antioxidant state, an early up-regulation of peroxidase activity was observed in elicited cells, whereas non-enzymatic properties and catalase activity were enhanced at the end of post-elicitation. These findings suggest the involvement of an efficient antioxidant defense system in the adaptive response of cells to fungal elicitation. Altogether, these results indicated that H. perforatum elicited cells represent a promising experimental system for scale-up production of naphtodianthrones for medicinal uses
    Plant Cell Tissue and Organ Culture 04/2015; 122(1). DOI:10.1007/s11240-015-0762-y · 2.61 Impact Factor
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    ABSTRACT: The effects of polysaccharide elicitors such as chitin, pectin, and dextran on the production of phenylpropanoids (phenolics and flavonoids) and naphtodianthrones (hypericin and pseudohypericin) in Hypericum perforatum shoot cultures were studied. Nonenzymatic antioxidant properties (NEAOP) and peroxidase (POD) activity were also observed in shoot extracts. The activities of phenylalanine ammonia lyase (PAL) and chalcone-flavanone isomerase (CHFI) were monitored to estimate channeling in phenylpropanoid/flavonoid pathways of elicited shoot cultures. A significant suppression of the production of total phenolics and flavonoids was observed in elicited shoots from day 14 to day 21 of postelicitation. This inhibition of phenylpropanoid production was probably due to the decrease in CHFI activity in elicited shoots. Pectin and dextran promoted accumulation of naphtodianthrones, particularly pseudohypericin, within 21 days of postelicitation.The enhanced accumulation of naphtodianthrones was positively correlated with an increase of PAL activity in elicited shoots. All tested elicitors induced NEAOP at day 7, while chitin and pectin showed increase in POD activity within the entire period of postelicitation.The POD activity was in significantly positive correlation with flavonoid and hypericin contents, suggesting a strong perturbation of the cell redox system and activation of defense responses in polysaccharide-elicited H. perforatum shoot cultures.
    The Scientific World Journal 12/2014; 2014(Article ID 609649):10 pages. DOI:10.1155/2014/609649 · 1.73 Impact Factor
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    ABSTRACT: Considering the global interest for the natural sources of antioxidants, macrofungi have become attractive for research activities. The aim of this study was to investigate the antioxidant properties of three Boletus species: B. appendiculatus, B. satanas and B. lupinus. Specimens were collected from Macedonian oak forest on Galichica Mountain in autumn 2011. Antioxidant properties of the selected fungi were assayed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity method in the methanolic extracts. The contents of phenolic compounds and flavonoids present in the mature fruiting bodies were also analyzed. A highly significant correlation between antioxidant capacity and phenolic content was found, indicating that phenolic compounds are a major contributor to antioxidant activity in the mushroom fruiting bodies. The highest antioxidant capacity and the lowest effective concentrations of the samples at which DPPH radicals were scavenged by 50% (EC50 values) were confirmed in B. appendiculatus extracts.
    Horizons 08/2014; 10(1):163-172.
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    Oliver Tusevski · Aneta Kostovska · Ana Iloska · Ljubica Trajkovska · Sonja Gadzovska Simic
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    ABSTRACT: Investigations have been made to study the production of phenolic compounds (total phenolics, flavonoids and phenylpropanoids) and total antioxidant capacity in 27 Macedonian traditional medicinal plants to improve its potential as a source of natural antioxidants. Antioxidant potential of plant extracts was analyzed by five different assays: cupric reducing antioxidant capacity (CUPRAC), phosphomolybdenum method (PM), reducing power (RP), 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 2,2’-azinobis(3- ethylbenzothiazoline-6-sulphonic acid (ABTS•+) radical scavenging activity. Origanum vulgare extract consistently exhibited the highest content of phenolic compounds and the strongest antioxidant capacity based on the tests performed, and can be proposed as a promising source of natural antioxidants. Melissa officinalis and Salvia ringens were also identified as valuable sources of antioxidant compounds. A positive linear correlation between antioxidant activity and total phenolics, flavonoids and phenylpropanoids indicates that these compounds are likely to be the main antioxidants contributing to the observed activities of evaluated plants. These findings suggest that the medicinal plants studied in this paper are good sources of bioactive compounds for the food and pharmaceutical industries.
    Central European Journal of Biology 08/2014; 9(9). DOI:10.2478/s11535-014-0322-1 · 0.63 Impact Factor
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    ABSTRACT: Regeneration of transgenic shoots was achieved from Hypericum perforatum L. hairy roots on hormone-free MS/B5 medium for a period of 4 weeks under a photoperiod of 16-h light. A control experiment was set up with root segments obtained from in vitro grown seedlings. Investigations have been made to study the production of phenolic compounds in non transgenic and transgenic shoot cultures. Six groups of phenolic compounds such as phenolic acids, flavonols, flavan-3-ols, naphtodianthrones, phloroglucinols, and xanthones were recorded in the transgenic shoots. Chlorogenic acid was found as the most representative phenolic acid in shoot extracts. With regard to the class of quercetin derivatives in transformed shoots, quercetin 6-C-glucoside usually dominated among the glycosides followed by quercitrin and hyperoside. The analysis of flavan-3-ols in transgenic shoots resulted in the identification of epicatechin and proanthocyanidin dimers. One of the main achievements in this study was considerably enhanced hypericin and pseudohypericin production in transgenic shoots. The concentration of identified naphtodianthrones was about 12-fold higher in transformed shoots compared to control. Chromatographic analysis of phloroglucinols in transgenic shoots resulted in the identification of hyperforin, while its homolog adhyperforin was detected in traces. A twofold higher content of hyperforin was observed in transgenic shoots compared to control. Although mangiferin was found as the main representative xanthone in shoot extracts, several other xanthones identified as c-mangostin isomers, trihydroxy-1-methoxy-C-prenyl xanthone, garcinone E, and banaxathone E were de novo synthesized in transformed shoots. Therefore, H. perforatum transgenic shoots could be considered as a source for rapid and increased production of naphtodianthrones and other specific phenolic compounds.
    Acta Physiologiae Plantarum 07/2014; 36(10). DOI:10.1007/s11738-014-1627-4 · 1.52 Impact Factor
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    ABSTRACT: St. John’s wort (Hypericum perforatum L.) has received considerable interest in recent years due to the increased market demand for Hyperici herba crude material as a source of bioactive pharmaceuticals. Hypericum extracts contain a complex mixture of bioactive metabolites, mainly naphthodianthrones (hypericin and pseudohypericin), phloroglucinols (hyperforin and adhyperforin) and flavonoids with a broad spectrum of biological effects. As a consequence of the great commercial potential of this species, attempts have been focused on improvement of secondary metabolite production by application of in vitro culture methods. Although H. perforatum in vitro cultures are known to produce naphtodianthrones, there has been little work to investigate whether these compounds are inducible by genetic transformation. The main objective of this study was to establish an efficient Agrobacterium rhizogenes A4-mediated transformation system that would result in the rapid formation of H. perforatum transgenic shoots for the purposes of studying the naphtodianthrone production. Naphtodianthrones in control and transformed shoots were analyzed using high-performance liquid chromatography (HPLC) coupled with diode-array detection (DAD) and tandem mass spectrometry (MSn) with electrospray ionization (ESI). Chromatographic analyses revealed that pseudohypericin, hypericin and protopseudohypericin were the only naphtodianthrones identified in both control and transgenic shoots. The concentration of hypericin and pseudohypericin was about 12-fold higher in transformed shoots compared to control. Regarding the quantitative aspect, pseudohypericin was found as the main naphthodianthrone in transgenic shoots, usually present in 3.5-fold higher amounts than hypericin. In addition, a 3-fold increase of protopseudohypericin was also found in transgenic shoots. Transgenic shoot cultures accumulated significantly higher levels of total naphtodianthrones (113.74±6.13 mg•100g-1 DW) compared to control shoots (10.67±0.88 mg•100g-1 DW). The direct mode of shoot regeneration, as observed in H. perforatum, is a desirable trait when the aim is to obtain genetically stable and viable plants for the purposes of studying the production and accumulation of bioactive compounds. Therefore, H. perforatum transgenic shoots could be considered as a source for rapid and increased production of naphtodianthrones.
    8th CMAPSEEC, Durres, Albania; 05/2014
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    ABSTRACT: the Republic of Macedonia Secondary metabolites have a specific role in the organic matter and nutrient cycling in forest ecosystems, especially in the process of litter decomposition. Decomposition of Common beech (Fagus sylvatica L.) leaf, branch, and acorn litter was followed by litter-bag experiments in the Common beech ecosystem Calamintho grandiflorae-Fagetum in Mavrovo National Park (Macedonia) for almost 7 years. The main goal of the present study was to analyze the dynamics of soluble phenolic com-pounds during litter decomposition. We analyzed total phenolics, flavonoids and anthocyanins content in the course of the decomposition of leaves, branches and acorns. The concentration of total phenolics, flavonoids and anthocyanins in leaves decreased follow-ing a simple exponential model. All of these compounds followed a 3-step dynamics in branch and acorn litter. The decrease in absolute mass of all compounds in all three litter fractions was described by simple exponential or logarithmic models. Total phenolics, flavonoids and anthocyanins were found in low concentrations. These low concentration point out to a new hypothesis, yet to be proved, that the phenolics do not slow down the decomposition process and contribute to the low limit value for this forest ecosystem. Секундарните метаболити имаат специфична улога во кружењето на материјата во шумските екосистеми, а особено во деградацијата на мртвата органска материја. Деградацијата на мртвата органска материја (листови, гранчиња и буклинки) беше следена со помош на огледни вреќички за деградација во буковиот екосистем Calamintho grandiflorae-Fagetum во Националниот парк "Маврово" (Македонија) во период од скоро 7 години. Главна цел на овој труд беше да се испита динамиката на фенолните соединенија во текот на деградацијата на мртвата органска материја. За реализација на целта на овој труд беше извршена анализа на концентрацијата и количеството на вкупни растворливи феноли, флавоноиди и антоцијани. Концентрацијата на вкупни феноли, флавоноиди и антоцијани во листовите се намалуваше според прост експоненцијален модел. Во гранчињата и буклинките, сите испитувани фенолни соединенија покажаа 3-степена динамика во текот на деградацијата. Вредностите за вкупното количество (маса) феноли, флавоноиди и антоцијани во сите три испитувани фракции покажаа континуирано намалување, кое најдобро се опишува со прости експоненцијални или логаритамски модели. Резултатите од ова истражување се во согласност со претходните констатации за ниската гранична вредност на деградацијата на мртвата органска материја во буковиот екосистем во Националниот парк "Маврово". Добиените резултати за релативно ниска концентрација на вкупните феноли, флавоноиди и антоцијани веројатно ј поддржуваат хипотезата дека овие секундарни метаболити не го забавуваат процесот на деградација. Клучни зборови: вкупни феноли, флавоноиди, антоцијани, деградација на мртвата органска материја, бука (Fagus sylvatica), листови, гранчиња, буклинки.
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    Vesna Levkov · Sonja Gadzovska Simic · Oliver Tusevski · Natasha Gjorgovska · Natasa Mateva
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    ABSTRACT: The presence of phenolic compounds in the milk and cheese is a result of their transfer from plant to milk and can affect their antioxidant activity. The objective of this work is to make a survey of the prevalence of the total phenolic compounds (TPC) in certain stages during cheese ripening as well as to determinate their final concentration in mature cheese. The obtained results show differences in the content of TPC between cheese samples from two batches (1 and 2). During the cheese ripening and after the dry salting and brining decreasing in the content of TPC has been noticed in both cheese batches. This is a result of number of chemical and enzymatic reactions as well as the high concentration of NaCl that inhibits the phenolic compounds to react with Folin reagent.
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    ABSTRACT: Hypericum perforatum L. is a medicinal plant considered as an important natural source of secondary metabolites with a wide range of pharmacological attributes. Hairy roots (HR) were induced from root segments of in vitro grown seedlings from H. perforatum after cocultivation with Agrobacterium rhizogenes A4. Investigations have been made to study the production of phenolic compounds in dark-grown (HR1) and photoperiod-exposed (HR2) cultures. The chromatographic analysis of phenolic acids, flavonols, flavan-3-ols, and xanthones revealed marked differences between HR1 and HR2 cultures. The production of quinic acid, kaempferol, and seven identified xanthones was increased in HR2. Moreover, HR2 showed a capability for de novo biosynthesis of two phenolic acids (3-p-coumaroylquinic acid and 3-feruloylquinic acid), three flavonol glycosides (kaempferol hexoside, hyperoside, and quercetin acetylglycoside), and five xanthones (tetrahydroxy-one-methoxyxanthone, 1,3,5-trihydroxy-6-methoxyxanthone, 1,3,5,6-tetrahydroxy-2-prenylxanthone, paxanthone, and banaxanthone E). On the other side, HR1 cultures were better producers of flavan-3-ols (catechin, epicatechin, and proanthocyanidin dimers) than HR2. This is the first comparative study on phenolic profile of H. perforatum HR cultures grown under dark and photoperiod conditions.
    The Scientific World Journal 12/2013; 2013:602752. DOI:10.1155/2013/602752 · 1.73 Impact Factor
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    ABSTRACT: Hypericum perforatum L. is a common perennial plant with a reputed medicinal value. Investigations have been made to develop an efficient protocol for the identification and quantification of secondary metabolites in hairy roots (HR) of Hypericum perforatum L. HR were induced from root segments of in vitro grown seedlings from H. perforatum, after co-cultivation with Agrobacterium rhizogenes A4. Transgenic status of HR was confirmed by PCR analysis using rolB specific primers. HR had an altered phenolic profile with respect to phenolic acids, flavonol glycosides, flavan-3-ols, flavonoid aglycones and xanthones comparing to control roots. Phenolics in control and HR cultures were observed to be qualitatively and quantitatively distinct. Quinic acid was the only detectable phenolic acid in HR. Transgenic roots are capable of producing flavonol glycosides such as quercetin 6-C-glucoside, quercetin 3-O-rutinoside (rutin) and isorhamnetin O-hexoside. The HPLC analysis of flavonoid aglycones in HR resulted in the identification of kaempferol. Transformed roots yielded higher levels of catechin and epicatechin than untransformed roots. Among the twenty-eight detected xanthones, four of them were identified as 1,3,5,6-tetrahydroxyxanthone, 1,3,6,7-tetrahydroxyxanthone, γ-mangostin and garcinone C were de novo synthesized in HR. Altogether, these results indicated that H. perforatum HR represent a promising experimental system for enhanced production of xanthones.
    Central European Journal of Biology 10/2013; 8(10). DOI:10.2478/s11535-013-0224-7 · 0.63 Impact Factor
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    Sonja Gadzovska-Simic · Oliver Tusevski
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    ABSTRACT: Investigations have been made to develop an efficient protocol for identification and quantification of phenolic acids and flavonoids in hairy roots (HR) of Hypericum perforatum L. HR were induced from root segments of in vitro grown seedlings from H. perforatum, after co-cultivation with Agrobacterium rhizogenes A4. Transgenic status of HR was confirmed by PCR analysis using rolB specific primers. HR grew rapidly on hormone-free medium and had plagiotropic growth with vigorous production of lateral roots. Phenolic acids and flavonoids in control roots and HR were analyzed using HPLC/DAD/ESI-MSn. Quinic acid was the only detectable phenolic acid in HR. Transgenic roots produced flavonol glycosides such as quercetin 6-C-glucoside, rutin and isorhamnetin O-hexoside. Chromatographic analysis of flavonoid aglycones in HR resulted in the identification of kaempferol. Transformed roots yielded higher levels of catechin and epicatechin than untransformed roots. H. perforatum HR represent promising experimental system for enhanced production of phenolic compounds.
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    ABSTRACT: Hypericum perforatum is a well known medicinal plant. The main pharmacological properties are due to the presence of naphtodianthrones such as hypericin and pseudohypericin. Unfortunately the levels of these compounds vary under different environmental conditions. Elicitation of in vitro cultures is a useful approach to enhance and extend production of desirable products. Therefore, the effects of salicylic acid were characterized on different explants of H. perforatum L. (cells, calli and shoots) cultured in vitro. It appears at first that salicylic acid did not affect growth and development of these explants. In addition, the production of both hypericin and pseudohypericin has doubled in elicited cell suspension cultures but not in the two other cultures. Furthermore, phenylpropanoids that are among the most frequently observed metabolites affected upon treatment of in vitro culture material with elicitors, were produced and the enzymatic activities of phenylalanine ammonia lyase and of chalcone isomerase were stimulated upon elicitation. These effects were dependant of the type of in vitro culture, the concentration of salicylic acid and the duration postelicitation. The H. perforatum cells were globally more sensitive to salicylic acid elicitation when maintained in an undifferentiated state and particularly in cell suspension cultures. In the absence of glands considered as the sites of naphtodianthrones biosynthesis, cells and calli were capable of producing these compounds. This implies that salicylic acid could act at biosynthesis level but not for the accumulation of both hypericin and pseudohypericin. Consequently, the regulation of this process is more complex than cited in the literature involving the responsibility of only Hyp-1 gene, encoding a hypericin biosynthetic enzyme, cloned and characterized from H. perforatum.
    Plant Cell Tissue and Organ Culture 11/2012; 113(113):25-39. DOI:10.1007/s11240-012-0248-0 · 2.61 Impact Factor
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    Conference on Medicinal and Aromatic plants of South East European Countries, 7th CMAPSEEC; 05/2012
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    ABSTRACT: We investigated the production of phenylpropanoids (phenolic compounds, flavanols, flavonols and anthocya-nins) and naphtodianthrones (hypericins) in elicited Hypericum perforatum L. cell suspensions. To determine whether secondary metabolite production could be enhanced, Hypericum cell suspensions were exposed to mycelia extract from the fungus Aspergillus flavus. Elicited Hypericum cell suspension cultures displayed reduced growth and viability and a modification of secondary metabolites production. Anthocyanins were only stimulated in fungal-elicited cell suspensions. Secondary metabolite production in elicited Hypericum cells revealed an antagonism between the flavonoid/naphtodian-throne and anthocyanin pathways. The data suggest a modification of the channeling of the phenylpropanoid compounds. Together, these results represent useful data for monitoring the channeling in different secondary metabolite pathways during the scaled-up production of naphtodianthrones for medicinal uses.
    Archives of Biological Sciences 01/2012; 64:113-121. DOI:10.2298/ABS1201113G · 0.61 Impact Factor
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    Sonja Gadzovska-Simic
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    ABSTRACT: Hypericum perforatum L. in vitro cultures with different morphological characteristics referred to shoots, calli and cells were used as experimental models for studying of secondary metabolite productions. To determine whether production of secondary metabolites could be enhanced, in vitro cultures were exposed to exogenous application of phytohormones and chemical elicitors (jasmonic acid, salicylic acid, pectin and chitin). To assess responses to biotic elicitors, cells were treated with mycelia extracts from three fungi Fusarium, Phoma and Botrytis. Shoot cultures exhibited a higher yield of secondary metabolites, but calli and cells showed remarkably fast and strong response to applied elicitors. Secondary metabolite production in Hypericum cells can be partially changed by supplementation of these elicitors and well controlled cultures could be used as a source for rapid and increased production of hypericin and pseudohypericin. This book is intended for graduated students and researchers in Plant Cell and Tissue Culture and Plant Molecular Biology. Students and researchers who are just beginning to work in this field will also find much valuable information in this book.
    08/2010; LAP Lambert Academic Publishing, Saarbrücken, Germany., ISBN: 978-3-8383-8304-0
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    ABSTRACT: Recently, research activities in plant secondary metabolites are focused on their properties as a new source of natural antioxidants. In this study, nonenzymatic antioxidant acitvity (NEAA) of 20 Macedonian medicinal plants was determined using -carotene/linoleic acid oxidation method. Plant species were collected on the Jablanica Mt. at the altitude from 1450 to 2000 meters and different plant parts (leaves, stems and flowers) were used for antioxidant analyses. Results from this study shown that some plant species such as Geum coccineum L., Stachys alpina L., Achillea millefolium L. were identified among the best sources of antioxidant compounds. The values for NEAA were highly correlated to the concentration of total phenolics (r ! 0.56) in plant extracts. The highest significant correlation between NEAA and phenolic amount was noticed in methanolic extracts of leaves (r=0.689), confirmed that phenolic compounds were dominant antioxidant components in these plant parts. Therefore, traditional Macedonian me - di cinal plants could be used as a potential available source of products with antioxidant properties in cosmetics, pharmaceutics and food industry.
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    20th Congress of Chemists and Technologysts of Macedonia; 01/2008
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    20th Congress of Chemists and Technologysts of Macedonia; 01/2008

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