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Different Extracts (different + extract)
Selected AbstractsStudying the anti-tyrosinase effect of Arbutus andrachne L. extractsINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 4 2008R. A. Issa Synopsis Arbutus andrachne L. is widely distributed in Jordan. Tyrosinase is the key enzyme in the biosynthesis of melanin. This preliminary study was carried out to assess the possible anti-tyrosinase activity of A. andrachne extracts. Arbutin, hydroquinone and kojic acid were selected as inhibitor standards. Five different extracts (chloroform, butanol, ethanol, methanol and water) were prepared from A. andrachne stems and their activities were compared with the selected tyrosinase inhibitors. IC50 was measured for both, standard and plant extracts. Among the different extracts, the methanolic extract exhibited the highest anttyrosinase activity with an IC50 value (1 mg mL,1). Furthermore, 9 mg A. andrachne methanolic extract showed 97.49% inhibition of tyrosinase activity. Arbutin, hydroquinone, ,-sitosterol and ursolic acid were identified in the different extracts of A. andrachne by thin layer chromatography (TLC) and isolated by preparative TLC from the methanolic and chloroform stem extracts, respectively. Résumé Arbutus andrachne L. est largement répandu en Jordanie. La tyrosinase est un enzyme clé dans la biosynthèse de la mélanine. Cette étude préliminaire est menée dans le but de juger de la possible activité anti-tyrosinase des extraits d'A. andrachne L. L'arbutine, l'hydroquinone et l'acide kojique ont été sélectionnés comme inhibiteurs de référence. Cinq extraits différents (chloroforme, butanol, éthanol, méthanol et eau) ont été préparés à partir de tiges d'A. andrachne L. et leurs activités ont été comparées à celles des inhibiteurs de tyrosinase sélectionnés. L'IC50 a été mesurée à la fois pour les références et les extraits de plantes. Parmi les différents extraits, l'extrait méthanolique montre l'activité anti-tyrosinase la plus élevée avec une valeur d'IC50 de 1 mg mL,1. De plus, 9 mg d'extrait méthanolique d'A. andrachne L. possède une activité inhibitrice de la tyrosinase de 97.49%. L'arbutine, l'hydroquinone, le ,-sitostérol et l'acide ursolique ont été identifiés dans les différents extraits par chromatographie sur couches minces et isolés par chromatographie préparative, respectivement à partir des extraits méthanoliques et chloroformiques de tiges. [source] Antioxidant properties of methanolic extracts from different parts of Sclerocarya birreaINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2008Abdalbasit A. Mariod Summary The methanolic extracts from Sclerocarya birrea leaves (SCL), roots (SCR), barks (SCB), and kernel oil cake (SCK) were examined for radical scavenging capacities and antioxidant activities. The total phenolics of the extracts was determined spectrophotometrically according to the Folin-Ciocalteau method using gallic acid as standard solution. The total phenolic compounds were found as 304.5, 367.5, 593, 148.0 and 258.0 mg g -1 of dry product, respectively. The extracts of SCL, SCR, SCB and SCK were markedly effective in inhibiting the oxidation of linoleic acid and subsequent bleaching of ,-carotene in comparison with the control. Based on oxidation of ,-carotene/linoleic acid, the SCK extract is the most effective followed by SCR, SCL and SCB extract. The antioxidant activity determined by the DPPH (1,1-diphenyl-,-picrylhydrazyl) method revealed that the SCK extract had the highest antioxidant activity on DPPH free radicals followed by SCB, SCR and SCL extracts. The effect of different extracts on the oxidative stability of sunflower oil at 70 °C was tested in the dark and compared with BHA. The oil peroxide values (PVs) were generally lower with the addition of extract in comparison to a control. [source] Qualitative and quantitative responses of Diabroticina (Coleoptera: Chrysomelidae) to cucurbit extracts linked to species, sex, weather and deployment methodJOURNAL OF APPLIED ENTOMOLOGY, Issue 3 2008G. Cabrera Walsh Abstract Toxic baits and traps for Diabroticina, based on bitter cucurbit extracts, have been utilized for a number of years with inconsistent results. Four species of bitter Cucurbitaceae were compared in the field for their attractancy to species of Diabroticina in Argentina and the United States. The comparisons were made with polyester fabrics treated with known volumes of different cucurbit extracts, against a standard cucurbit extract of bitter Hawkesbury watermelon (Citrullus lanatus (Thunberg) Matsumura and Nakai). The factors evaluated were: the attractancy of the different extracts in terms of beetle numbers, species and sex of the Diabroticina caught; influence of different fabrics on such attraction; and influence of several weather variables on the catches. The most attractive species was Cayaponia bonariensis (Miller) Martinez Crovetto, however, practical considerations indicated that Cucumis myriocarpus Naudin and Hawkesbury watermelon may be better choices from the commercial perspective. No single weather factor could explain the catches throughout the sample range, but different temperature and barometric pressure ranges provided some predictive value. Although the susceptibility to weather conditions and a strong male dominance in the catches raise the question of the usefulness of cucurbitacins as the main component in toxic baits or traps, these drawbacks may prove to be less important in widespread bait applications and Diabroticina management in vegetable crops. [source] ANTIBACTERIAL ACTIVITY AND CHEMICAL CONSTITUTIONS OF OLEA EUROPAEA L. LEAF EXTRACTSJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2010MIHRIBAN KORUKLUOGLU ABSTRACT The in vitro antimicrobial activity of aqueous, acetone, diethyl ether and ethyl alcohol extracts of olive leaves (Olea europaea L.) was studied. The aqueous extract of olive leaves had no antibacterial effect against the test microorganisms, whereas acetone extract showed inhibitory effect on Salmonella enteritidis, Bacillus cereus, Klebsiella pneumoniae, Escherichia coli, Enterococcus faecalis, Streptococcus thermophilus and Lactobacillus bulgaricus. Furthermore, the antimicrobial activities of some phenolic compounds against microorganisms were tested. The most effective compound was found to be oleuropein while syringic acid was found ineffective. The characterization of phenolic compounds in different extracts determined by high performance liquid chromatography-air pressure chemical ionization-mass spectrometry detector (HPLC-APCI-MSD GC-MS) gas chromatography-mass spectrometry (GC-MS). The acetone and the ethyl alcohol extracts had the most and the least oleuropein content, respectively. PRACTICAL APPLICATIONS In recent years the extracts of many plant species have become popular, and attempts to characterize their bioactive principles have gained speed for many pharmaceutical and food-processing applications. Especially, antimicrobial properties of plants have revived as a consequence of current problems associated with the use of chemical preservatives. Because of consumers' negative perspectives of synthetic preservatives, attention is shifting toward natural alternatives. The findings suggest that olive leaf extracts and their phenolic compounds have good potential as antibacterial substances in food preservation as they may be more acceptable to consumers and the regulatory agencies in comparison with synthetic chemical compounds. [source] Cytotoxic effects of gingival retraction cords on human gingival fibroblasts in vitroJOURNAL OF ORAL REHABILITATION, Issue 4 2004C.-M. Liu summary, The objective of this study was to determine the cytocompatibility of three different extracts of gingival retraction cords and to compare the cytotoxic effect of these materials on human gingival fibroblasts. Gingival retraction cords impregnated with aluminium sulphate (Gingi-Aid), dl -adrenaline HCl (Gingi-Pak) and non-drug-impregnated cord (Gingi-Plain) were eluted with culture medium for 10 min and 24 h. Cytotoxicity was judged using a tetrazolium bromide reduction assay. Our data demonstrated that gingival retraction cords applied alone almost completely inhibited cell viability (P < 0·05). In addition, the results also showed that the eluates from aluminium sulphate-impregnated cord, dl -adrenaline HCl-impregnated cord and non-drug-impregnated cord were cytotoxic to primary human gingival fibroblast cultures (P < 0·05). The cell viability of incubation of gingival fibroblasts containing 10-min eluates of aluminium sulphate, dl -adrenaline HCl and non-drug-impregnated cord was 61, 21 and 70%, respectively. The cell viability of incubation of gingival fibroblasts containing 24 h eluates of aluminium sulphate, dl -adrenaline HCl and non-drug-impregnated cord was 68, 58 and 72%, respectively. It was found that dl -adrenaline HCl-impregnated gingival retraction cord was the most toxic gingival retraction cord among the materials tested in all cultures (P < 0·05). The cytotoxicity decreased in an order of dl -adrenaline HCl-impregnated cord > aluminium sulphate-impregnated cord > non-drug-impregnated cord. The extent or degree of the cytotoxicity depended on the materials tested. Gingival retraction cords have significant potential for gingival toxicity. Careful management of gingiva retraction cords would lower the risk of potential gingival tissue damage during clinical application procedure and thus increase the success of prosthodontic procedures. [source] In-vitro and in-vivo antioxidant activity of different extracts of the leaves of Clerodendron colebrookianum Walp in the ratJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 12 2003D. Rajlakshmi ABSTRACT The in-vitro antioxidant activities of different concentrations of the water, alcoholic, petroleum ether and ethyl acetate extracts of the dried leaves of Clerodendron colebrookianum Walp, and in-vivo antioxidant activity of the water extract was studied in experimental rat models. The results obtained from in-vitro lipid peroxidation induced by FeSO4 -ascorbate in rat liver homogenate showed a significant inhibition of lipid peroxidation by different extracts of C. colebrookianum leaf. Water extracts at concentrations (w/v) of 1:30, 1:50, 1:200 and 1:1000 showed the strongest inhibitory activity over the other organic extracts, suggesting maximum antioxidant effect. Chronic feeding of the water extract to Wistar albino rats (both sexes, 150,200g) in 1 or 2g kg,1/day doses for 14 days significantly increased the ferric reducing ability of plasma by 19% and 40% on the seventh day, and by 45% and 57% on the fourteenth day of treatment, respectively. Thiobarbituric acid reactive substances (TBARS), as a marker of lipid peroxidation, and some cellular antioxidants (superoxide dismutase, catalase and reduced glutathione) were estimated in heart, liver and kidney. There was a significant reduction in hepatic and renal TBARS with both the doses, without any change in myocardial TBARS. There was no change in the level of antioxidants in heart, liver and kidney, except for the hepatic superoxide dismutase. The findings of this study showed that the leaf extract of C. colebrookianum increased the antioxidant capacity of blood and had an inhibitory effect on the basal level of lipid peroxidation of liver and kidney. This lends scientific support to the therapeutic use of the plant leaves, as claimed by the tribal medicine of North-East India. [source] Chemical fingerprinting of Andrographis paniculata using HPLC, HPTLC and densitometryPHYTOCHEMICAL ANALYSIS, Issue 5 2004Alpana Srivastava Abstract An attempt has been made to develop a method by which to determine the chemical ,ngerprint of Andrographis paniculata (Acanthaceae). High-performance thin layer chromatography (HPTLC) was used to analyse hexane, chloroform, methanol and water extracts of leaves of A. paniculata. A computerised densitometer was applied to the two-dimensional spectrographic image analysis of the HPTLC plates. An HPLC equipped with a photodiode array detector was used for the analyses of these different extracts. The analyses showed that andrographolide and neoandrographolide are absent in the hexane extract but are present in greater amounts in the methanol extract as compared with the other extracts. These chromatograms may serve as a chemical ,ngerprint of the drug A. paniculata for quality control purposes and in the preparation of formulations based on the drug. Copyright © 2004 John Wiley & Sons, Ltd. [source] Evaluation of antioxidant and antimicrobial properties of Soymida febrifuga leaf extractsPHYTOTHERAPY RESEARCH, Issue 7 2008Boreddy Srinivas Reddy Abstract The present study was designed to evaluate the antioxidant and antimicrobial properties of hexane (LH), methanol (LM) and aqueous (LA) extracts of Soymida febrifuga (Maliaceae) leaves, which is a traditional folk medicine in India. No pharmacological evaluation of this plant (except antiplasmodial activity) has been reported to date. Antioxidant activity of different extracts was evaluated by DPPH free radical scavenging activity, taking total phenolic content (TPC) as an index. Antimicrobial activity was tested against six bacterial and five fungal strains using the agar hole diffusion method and the minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) were determined for all the test organisms against the extracts. The results showed that the methanol and aqueous extracts of leaf had a higher antioxidant activity and total phenolic content than the hexane extract. The antioxidant activity and TPC of the extracts were highly correlated. Extracts also showed several degrees of antimicrobial activity against different microbes. The methanol extract was more potent against Aspergillus fumigatus and Candida tropicana. The lowest MIC values obtained for LM, LA and LH were 78, 156, 625 µg/mL against A. fumigatus, C. tropicana and C. albicans, respectively. Hence, this study confirms that Soymida febrifuga leaves possess potent antioxidant and antimicrobial activity. Copyright © 2008 John Wiley & Sons, Ltd. [source] Effect of parsley (Petroselinum crispum (Mill.) Nym. ex A.W. Hill, Apiaceae) extracts on some biochemical parameters of oxidative stress in mice treated with CCl4PHYTOTHERAPY RESEARCH, Issue 8 2007Mira Popovi Abstract The in vitro and in vivo antioxidant activity of different extracts of leaves and root of parsley (Petroselinum crispum (Mill.) Nym. ex A.W. Hill, Apiaceae) were studied. Free radical scavenging capacity (RSC) was evaluated measuring the scavenging activity on the 2,2-diphenyl-1-picrylhydrazil (DPPH) and OH radicals. Also, the effects on lipid peroxidation (LP) were evaluated. The results obtained showed that all examined extracts act as good scavengers of DPPH and OH radicals and reduce the intensity of LP. The in vivo effects were evaluated on some antioxidant systems (activities of LPx, GSH-Px, Px, CAT and XOD, and GSH content) in the mice liver and blood after treatment with the examined parsley extracts, or in combination with carbon tetrachloride (CCl4). On the basis of the results obtained it can be concluded that the examined extracts exhibited a certain protective effect. However, combined treatments with CCl4 and the examined extracts showed both positive and negative synergism, inducing or suppressing the influence of CCl4 alone. Copyright © 2007 John Wiley & Sons, Ltd. [source] Analgesic and antiinflammatory activity of Cyclamen repandum S. et S.PHYTOTHERAPY RESEARCH, Issue 7 2007E. Speroni Abstract According to folk medicine some species belonging to the genus Cyclamen were used for their biological activities. Early investigation of the different species of the genus resulted in the isolation of triterpenic saponins. No phytochemical and biological data are available on C. repandum. As part of a series of phytochemical investigations for bioactive compounds from medicinal plants, Cyclamen repandum S. et S. was investigated. The present study sought to find the antiinflammatory and antinociceptive activities of C. repandum tubers in rats and mice. A preliminary screening was conducted with three different extracts in the tests used, particularly the paw edema and the writhing tests. Subsequently some saponins isolated from the ME extract, the more effective one, have been identified. This paper also describes the results of fractionation and bioassay guided chemical studies. Chemical investigation of the active extract afforded the isolation and characterization of six triterpenic saponins. The possible antiinflammatory and analgesic properties were investigated as the saponin content of the fractions allows to speculate on such aspect. Copyright © 2007 John Wiley & Sons, Ltd. [source] High-performance liquid chromatography and LC-ESI-MS method for identification and quantification of two isomeric polyisoprenylated benzophenones isoxanthochymol and camboginol in different extracts of Garcinia speciesBIOMEDICAL CHROMATOGRAPHY, Issue 8 2009Satyanshu Kumar Abstract A rapid, sensitive and simple reverse-phase high-performance liquid chromatography,electrospray ionization mass spectrometric method has been developed for the identification and quantification of two isomeric polyisoprenylated benzophenones, isoxanthochymol and camboginol, in the extracts of the stem bark, seeds and seed pericarps of Garcinia indica and in the fruit rinds of Garcinia cambogia. The separation of isoxanthochymol and camboginol was achieved on a Perkin Elmer RP8 column (10 × 2.1 mm with 5.0 µm particle size) using a solvent system consisting of a mixture of acetonitrile,water (80:20, v/v) and methanol,acetic acid (99.0:1.0, v/v) as a mobile phase in a gradient elution mode. The limits of detection and quantification were 5 and 10 µg/mL for isoxanthochymol and 50 and 100 µg/mL for camboginol, respectively. The intra- and inter-day precisions were 2.34 and 3.41% for isoxanthochymol and 3.35 and 3.66% for camboginol. The identity of the two isomeric compounds in the samples was determined on a triple quadrupole mass spectrometer with ESI interface operating in the negative ion mode. The method was used to identify and quantify isoxanthochymol and camboginol in the different extracts of two Garcinia species, Garcinia indica and Garcinia cambogia. Copyright © 2009 John Wiley & Sons, Ltd. [source] Identification and quantification of two antihepatotoxic coumarinolignoids cleomiscosin A and cleomiscosin B in the seeds of Cleome viscosa using liquid chromatography,tandem mass spectrometryBIOMEDICAL CHROMATOGRAPHY, Issue 4 2009Sunil K. Chattopadhyay Abstract A sensitive liquid chromatography/electrospray ionization tandem mass spectrometric (LC/ESI-MS/MS) method was developed for the identification and quantification of two antihepatotoxic coumarinolignoids cleomiscosin A and cleomiscosin B in different extracts of the seeds of Cleome viscosa. The separation of cleomiscosin A and cleomiscosin B was achieved on an RP18 column using a solvent system consisting of a mixture of acetonitrile,methanol (1:2, v/v) and acetonitrile,water,formic acid (5:95:0.3, v/v) as a mobile phase in a gradient elution mode. A multiple-reaction monitoring (MRM) method was developed for quantification of cleomiscosin A and cleomiscosin B in the seed extracts of Cleome viscosa. On the basis of signal-to-noise ratio of 3, the limit of detection in MRM mode for cleomiscosin A and cleomiscosin B were 1.0 and 4.0 ng/mL respectively. The method was validated in terms of linearity, accuracy and precision for 6 days. The method developed was found to be useful for identification and quantification of cleomiscosin A and cleomiscosin B in the different extracts of the seeds of Cleome viscosa. Copyright © 2008 John Wiley & Sons, Ltd. [source] High-performance liquid chromatography and LC-ESI-MS method for the identification and quantification of two biologically active isomeric coumarinolignoids cleomiscosin A and cleomiscosin B in different extracts of Cleome viscosaBIOMEDICAL CHROMATOGRAPHY, Issue 12 2008Sunil K. Chattopadhyay Abstract A rapid, sensitive and simple reverse-phase high-performance liquid chromatographic,electrospray ionization,mass spectrometry method for simultaneous determination of cleomiscosin A and cleomiscosin B has been developed and validated. The isomeric coumarinolignoids cleomiscosin A (1) and cleomiscosin B (2) were separated on a Waters symmetry C18 column with a solvent system composed of acetonitrile,methanol (1:2) and acetic acid,water (0.5 : 99.5) in a gradient elution mode. The absorption at 326 nm was chosen as the measuring wavelength in which resolution and baseline separation of compounds 1 and 2 could be obtained. The identity of the two isomeric compounds 1 and 2 in the samples were determined on a triple quadrupole mass spectrometer with ESI interface operating in the positive mode. Calibration curves were linear (r2 > 0.993) over the concentration range 20,200 µg/mL for cleomiscosin A and 10,200 µg/mL for cleomiscosin B with acceptable accuracy and precision, respectively. The intra-day and inter-day precision were 1.13 and 0.82% for cleomiscosin A and 1.78 and 1.28% for cleomiscosin B, respectively. The validated method was successfully applied for the analysis of the above two compounds in different extracts of Cleome viscosa. Copyright © 2008 John Wiley & Sons, Ltd. [source] High-performance liquid chromatographic method for identification and quantification of two isomeric coumarinolignoids,cleomiscosin A and cleomiscosin B,in extracts of Cleome viscosaBIOMEDICAL CHROMATOGRAPHY, Issue 11 2007Sunil K. Chattopadhyay Abstract A simple, accurate and reproducible reverse-phase HPLC method has been developed for identification and quantification of two isomeric coumarinolignoids, cleomiscosin A and B in different extracts of the seeds of Cleome viscosa using photodiode array detection at 326 nm. Cleomiscosin A and B were separated on a Waters symmetry C18 column (250 × 4.6 mm with 5.0 µm particle size) with an isocratic elution system composed of acetonitrile,methanol (1:2, v/v) and acetic acid,water (0.5:99.5, v/v) in the ratio of 40:60 (v/v). The calibration curves were linear (r2 > 0.997) in the concentration ranges of 20,100 µg/mL for both compounds. The limits of detection and quantification were 15 and 20 µg/mL for both cleomiscosin A and B. The intra- and inter-day precisions were 3.68 and 2.22% for cleomiscosin A and 4.22 and 5.06% for cleomiscosin B. The recoveries measured at two different concentration levels varied from 98.03 to 110.06%. The method was used to identify and quantify cleomiscosins A and B in different extracts of Cleome viscosa seeds. Copyright © 2007 John Wiley & Sons, Ltd. [source] Optimization of Allium sativum Solvent Extraction for the Inhibition of in Vitro Growth of Helicobacter PyloriBIOTECHNOLOGY PROGRESS, Issue 6 2002Pablo Cañizares Helicobacter pylori (Hp) is the bacterium responsible for serious gastric diseases such as ulcers and cancer. The work described here involved the study of the inhibitory power of Allium sativum extracts against the in vitro growth of Hp(Hp ivg). We used purple garlic of the "Las Pedroñeras" variety for this study. The effects of two different extraction methods (Soxhlet, stirred tank extractor) and four solvents with different characteristics (water, acetone, ethanol, and hexane) were investigated in terms of the efficiency of the extraction process. Satisfactory results were obtained in most cases in the activity tests, indicating that different extracts gave rise to good inhibitory activity against Hp ivg. The extracts that showed the highest bacteriostatic activities were selected to evaluate the influence of the most important operation variables on the extraction yield: stirring speed, operation time, garlic conditioning, and garlic storage time. The best results were obtained using ethanol and acetone as solvents in a stirred tank. The inhibitory powers of these extracts were compared to those shown by some commercial antibiotics used in the medical treatment of Hp infections. The results of this study show that garlic extracts produce levels of inhibition similar to those of the commercial materials. These extracts were also tested against other common bacteria, and equally satisfactory results were obtained. The research described here represents an important starting point in the fight against and/or prevention of peptic ulcers, as well as other pathologies associated with Hp infections such us gastric cancer. The extracted material can be used by direct application and involves a simple and economical extraction procedure that avoids isolation or purification techniques. [source] | ||||||||||||||||