6 research outputs found
Phytochemical and biochemical analysis of selected species of subfamily Polygonoideae (Polygonaceae A. L. de Jussieu 1789) from Central and Western Balkan regions.
U ovoj doktorskoj disertaciji prikazani su rezultati istraživanja 15 vrsta biljaka koje pripadaju rodovima Rumex, Polygonum, Bistorta, Persicaria i Fagopyrum, podfamilije Polygonoideae, familije Polygonaceae, sakupljenih na teritoriji centralnog i zapadnog Balkana u periodu od 2009-2011. godine. Sprovedena istraživanja su se odvijala u dva pravca: fitohemijska i biohemijsko-biološka ispitivanja. Predmet analiza bili su ekstrakti herbi i rizoma ispitivanih biljaka. Fitohemijska ispitivanja obuhvatila su, pored spektrofotometrijskog određivanja ukupnih fenola, ukupnih flavonoida i ukupnih antrahinonskih jedinjenja, i određivanje sadržaja 51 komponente iz standardne smeše različitih klasa fenolnih jedinjenja LC-MSMS metodom, odnosno hromatografsko profilisanje ekstrakata LC-DAD-MS metodom. Odabirom nekoliko različitih model sistema za merenje antioksidantne aktivnosti (neutralizacija DPPH radikala, redoks kapacitet - FRAP test, skevindžer aktivnost prema superoksidanjon radikalu, NO radikalu i OH radikalu, kao i inhibicija lipidne peroksidacije) procenjen je antioksidantni potencijal ekstrakata, dok je za procenu njihove antiinflamatorne aktivnosti korišćen potencijal inhibicije biosinteze medijatora inflamacije u humanim trombocitima (kao model sistemu). Mikrobiološka ispitivanja su obuhvatila određivanje potencijala ovih vrsta u inhibiciji rasta serije gram pozitivnih i gram negativnih sojeva batkerija. Konačno, urađena je analiza korelacije hemijskog sastava, biološke aktivnosti i pripadnosti taksonomskim grupama.Phytochemical and biochemical analysis of herbal and root ethanol extracts of 15 species belonging to different genera (Rumex, Polygonum, Bistorta, Persicaria and Fagopyrum) of subfamily Polygonoideae, was examined. Phytochemical characterization included spectrophotometric determination of total phenolic, total flavonoids and total anthraquinone contents, quantification of 51 secondary metabolites by LC/MS/MS analysis and chromatographic fingerprinting by LC/DAD/MS technique, of prepared extracts. The antioxidant activity was evaluated by measuring ferric reducing ability (FRAP) of the extracts and their radical scavenging capacity towards DPPH, OH, NO and O2– radicals, and inhibition of lipid peroxidation). Antiinflammatory activity was evaluated by LC/MS/MS monitoring of selected metabolites (12-(S)-HHT, 12(S)-HETE, PGE2 , PGF2α, and TXB2) formed in cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism. Human platelets were used as a source of enzymes, while inflammation was induced by calcimycin. The antibacterial activity of prepared extracts against nine bacterial strains was evaluated by microtiter assay with resazurin as a colorimetric growth indicator
Phytochemical and biochemical analysis of selected species of subfamily Polygonoideae (Polygonaceae A. L. de Jussieu 1789) from Central and Western Balkan regions.
U ovoj doktorskoj disertaciji prikazani su rezultati istraživanja 15 vrsta biljaka koje pripadaju rodovima Rumex, Polygonum, Bistorta, Persicaria i Fagopyrum, podfamilije Polygonoideae, familije Polygonaceae, sakupljenih na teritoriji centralnog i zapadnog Balkana u periodu od 2009-2011. godine. Sprovedena istraživanja su se odvijala u dva pravca: fitohemijska i biohemijsko-biološka ispitivanja. Predmet analiza bili su ekstrakti herbi i rizoma ispitivanih biljaka. Fitohemijska ispitivanja obuhvatila su, pored spektrofotometrijskog određivanja ukupnih fenola, ukupnih flavonoida i ukupnih antrahinonskih jedinjenja, i određivanje sadržaja 51 komponente iz standardne smeše različitih klasa fenolnih jedinjenja LC-MSMS metodom, odnosno hromatografsko profilisanje ekstrakata LC-DAD-MS metodom. Odabirom nekoliko različitih model sistema za merenje antioksidantne aktivnosti (neutralizacija DPPH radikala, redoks kapacitet - FRAP test, skevindžer aktivnost prema superoksidanjon radikalu, NO radikalu i OH radikalu, kao i inhibicija lipidne peroksidacije) procenjen je antioksidantni potencijal ekstrakata, dok je za procenu njihove antiinflamatorne aktivnosti korišćen potencijal inhibicije biosinteze medijatora inflamacije u humanim trombocitima (kao model sistemu). Mikrobiološka ispitivanja su obuhvatila određivanje potencijala ovih vrsta u inhibiciji rasta serije gram pozitivnih i gram negativnih sojeva batkerija. Konačno, urađena je analiza korelacije hemijskog sastava, biološke aktivnosti i pripadnosti taksonomskim grupama.Phytochemical and biochemical analysis of herbal and root ethanol extracts of 15 species belonging to different genera (Rumex, Polygonum, Bistorta, Persicaria and Fagopyrum) of subfamily Polygonoideae, was examined. Phytochemical characterization included spectrophotometric determination of total phenolic, total flavonoids and total anthraquinone contents, quantification of 51 secondary metabolites by LC/MS/MS analysis and chromatographic fingerprinting by LC/DAD/MS technique, of prepared extracts. The antioxidant activity was evaluated by measuring ferric reducing ability (FRAP) of the extracts and their radical scavenging capacity towards DPPH, OH, NO and O2– radicals, and inhibition of lipid peroxidation). Antiinflammatory activity was evaluated by LC/MS/MS monitoring of selected metabolites (12-(S)-HHT, 12(S)-HETE, PGE2 , PGF2α, and TXB2) formed in cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism. Human platelets were used as a source of enzymes, while inflammation was induced by calcimycin. The antibacterial activity of prepared extracts against nine bacterial strains was evaluated by microtiter assay with resazurin as a colorimetric growth indicator
Plant mediated synthesis of zero valent iron nanoparticles and its chracterisation
Nanoscale zero valent-iron (nZVI) particles represent an important material for diverse environmental applications because of the exceptional electron-donating properties, which can be exploited for applications such as reduction, catalysis, adsorption, and degradation of a broad range of pollutants. The search for “green” strategies leads to the advancement in the plantmediated synthesis of ZVI nanoparticles.Within the framework of this work, the possibility of synthesis of nano zerovalent iron (nZVI) was investigated using extracts of oak, mulberry, green tea, pomelo peel, fresh orange peel and orange peel that was previously dried. Also, the subject of the investigation was the characterization of the obtained nanomaterials
Optimization of extraction conditions for secondary biomolecules from various plant species
Extraction of plant secondary metabolites is an essential step in isolation
of natural products. Non-optimized extraction conditions can lead to losses,
degradation and modification of the biomolecules. In this paper, the
influence of different solvent mixtures, solvent amounts, temperature,
extraction time, and procedures for defatting on yield and profile of various
classes of secondary metabolites was investigated. Rumex alpinus was used for
the extraction of anthraquinones, Glycine max for isoflavonoids,
Chaerophyllum bulbosum for flavonoids and phenolic acids, Anthriscus
sylvestris for lignans and coumarins, alkaloids were extracted from Lupinus
albus and sesquiterpene lactones from Artemisia absinthium. Extraction
efficiency was evaluated by use of LC-DAD-ESI-MS/MS. The compromise
extraction solvent for all of the examined compounds is 80 % methanol, mixed
in ratio 13 : 1 with plant material. Maceration should last for six hours,
repeated four times with fresh solvent. Defatting of the extracts does not
lead to significant losses of the compounds of interest. It is acceptable to
use extraction and evaporation temperature of 60ºC, while the extracts should
be stored in the dark, on -20ºC. [Projekat Ministarstva nauke Republike
Srbije, br. 172058
In Vitro Study of Two Edible Polygonoideae Plants: Phenolic Profile, Cytotoxicity, and Modulation of Keap1-Nrf2 Gene Expression
Polygonum aviculare and Persicaria amphibia (subfam. Polygonoideae) are used in traditional cuisines and folk medicine in various cultures. Previous studies indicated that phytochemicals obtained from Polygonoideae plants could sensitize chemoresistant cancer cells and enhance the efficacy of some cytostatics. Here, the cytotoxic properties of chemically characterized ethanol extracts obtained from P. aviculare and P. amphibia, individually and in combination with doxorubicin (D), were determined against hepatocarcinoma HepG2 cells. Phenolic composition, cell viability, cell cycle, apoptosis, and the expression of Keap1 and Nrf2 were examined by following methods: LC-MS/MS, LC-DAD-MS, MTT, flow cytometry, and qRT-PCR. Extracts were rich in dietary polyphenolics. Synergistic cytotoxicity was detected for extracts combined with D. The observed synergisms are linked to the interference with apoptosis, cell cycle, and expression of Keap1-Nrf2 genes involved in cytoprotection. The combined approach of extracts and D could emerge as a potential pathway of chemotherapy improvement