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Publications (7)3.31 Total impact

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    ABSTRACT: 10 polyphenols were identified from 80% aqueous methanol extract (AME) of Markhamia platycalyx [(Baker) Sprague] leaf. Their structures were characterized as protocatechuic acid (1), E-caffeic acid (2), E-methyl caffeate (3), isoverbascoside (4), verbascoside (5), jacraninoside-I (6), cosmosiin (7), cinaroside (8), luteolin (9) and apigenin (10) based on chemical and extensive spectral studies (UV, ESI-MS, 1H, 13C and 1D/2D NMR). Biological evaluation indicated that AME is non-toxic to the experimental animals. It exhibited a significant inhibition of oedema after 1, 2, 3 and 4 h for all examined doses (250, 500 and 1 000 mg/kg). In comparison with silymarin, the AME demonstrated a significant hepatoprotective effect in the form of high reduction in elevated ALT and AST serum levels in regard to paracetamol treated group. As well as, it revealed a marked significant scavenging activity by 62.9, 82.5, 88.3, 83.7 and 83.7%, for the concentrations 20, 40, 60, 80 and 100 mg/ml of the extract, respectively, relative to L-ascorbic acid (86.8%), which was used as a reference antioxidant drug.
    Drug research. 04/2014;
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    ABSTRACT: Albizia species are rich in phenolics and terpenes in the different plant organs. They are widely used in traditional Chinese medicine. So this study investigated the phytochemical and biological activities of Albizia Anthelmintica. Column chromatography has been performed for the isolation of compounds. Bioactivity studies of A. anthelmintica leaves were carried out on aqueous ethanol extract and some pure compounds were tested for their antioxidant activities. Eight compounds have been isolated for the first time from A. anthelmintica. The aqueous ethanol extract of A. anthelmintica showed moderate anti-inflammatory activity and significant for both analgesic and antioxidant activities. Quercetin-3-O-β-D-glucopyranoside, kaempferol-3-O-β-D-glucopyranoside, kaempferol-3-O-(6β-O-galloyl-β-D-glucopyranoside and quercetin-3-O-(6β-O-galloyl-β-D-glucopyranoside) exhibited potent antioxidant scavenging activity towards diphenyl-picrylhydrazine.
    Pharmacognosy research. 01/2013; 5(2):80-85.
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    ABSTRACT: Bioassay-guided isolation using an in vitro assay testing for antischistosomiasis yielded a novel triterpene saponin, asparagalin A, from the n-butanol extract of the roots of Asparagus stipularis Forssk., Asparagaceae. The structure was elucidated by spectroscopic analysis and chemical transformations. Administration of asparagalin A resulted in a retardation of worm growth and locomotion at the first day and showed a significant activity of egg-laying suppression at 200 μg/mL concentration.
    Revista Brasileira de Farmacognosia 01/2012; 22(2):314-318. · 0.68 Impact Factor
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    ABSTRACT: Investigation of the aqueous alcoholic extract of Pyruscalleryana Decne. leaves led to the isolation of two new phenolic acids glycosides, namely protocatechuoylcalleryanin-3-O-β-glucopyranoside (1) and 3'-hydroxybenzyl-4-hydroxybenzoate-4'-O-β-glucopyranoside (2), together with nine known compounds among them lanceoloside A and methylgallate, which have been isolated for the first time from the genus Pyrus. Structures of the isolated compounds were established by spectroscopic analysis, including UV, IR, HRESI-MS, and 1D/2D NMR. The total extract and some isolated compounds were determined against DPPH (2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazinyl radical, for their free radical scavenging activity, the total alcoholic extract showed strong antioxidant activity while the two new compounds showed weak antioxidant activity.
    Carbohydrate research 01/2011; 346(1):64-7. · 2.03 Impact Factor
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    ABSTRACT: A novel biflavone di-C-glucoside, 6,6"-di-C-beta-D-glucopyranoside-methylene-(8,8")-biapigenin (1), was isolated from the leaves of Jatropha curcas L. (Euphorbiaceae), together with six known compounds; apigenin 7-O-beta-D-neohesperidoside (2), apigenin 7-O-beta-D-galactoside (3), orientin (4), vitexin (5), vicenin II (6), and apigenin (7). Their structures were determined on the basis of extensive chemical and spectroscopic analyses (UV, NMR and HRESI-MS). The immunomodulatory effect of an 80% aqueous methanol extract (AME) and compounds 1-5 (0.25 mg/kg body wt) to one-day-old specific pathogen-free (SPF) chicks was determined. Stimulation of both humoral and cell-mediated seroresponse was observed, especially those of AME and compound 1. Remarkable effective increases of the antibody titers, lymphocyte and macrophage cells, in blood were recorded. SPF chicks treated with the tested samples exhibited protection against Newcastle disease challenge virus after being vaccinated.
    Zeitschrift fur Naturforschung C 01/2009; 64(7-8):495-501. · 0.60 Impact Factor
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    ABSTRACT: Water-distilled essential oil from leaves and flowers of Micromeria nubigena H.B.K. (Lamiaceae) were analyzed by GC and GC/MS systems. The major components identified were thymol (36.9%), carvacrol (16.7%), pulegone (10.8%), caryophyllene oxide (4.6%) and (E)-phytol (3.2%). The major volatiles released by β-glucosidase treatment of the aqueous plant residue were (Z)-3-hexenol (31.2%), (Z)-2-hexenol (18.3%) and δ—cadinene (3.4%). The oil showed significant antibacterial activity against Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, and Pseudomonas aeruginosa, and antifungal activity against Candida albicans, Botrytis cinerea and Aspergillus niger, while the β-glucosidase-liberated fraction was inactive.
    Journal of Essential Oil Research - J ESSENT OIL RES. 01/2008; 20(5):452-456.
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    ABSTRACT: abstraCt Sixteen volatile compounds were identified from the n-hexane extract of the buds of Syzygium aromaticum by using gas chromatography-mass spectroscopy (GC-MS). The major components were eugenol (71.56 %) and eugenol acetate (8.99 %). The dichloromethane extract of the buds yielded limonin and ferulic aldehyde, along with eugenol. The flavonoids tamarixetin 3-O-b-D-glucopyranoside, ombuin 3-O-b-D-glu-copyranoside and quercetin were isolated from the ethanol extract; identifications of all these compounds were established by chemical and spectroscopic methods including 1D and 2D NMR. This is the first report of limonin, ferulic aldehyde and these flavonoids from this plant. All extracts and the isolated flavonoids showed strong antioxidant activity against 1, 2-diphenyl picrylhydrazyl (DPPH). Among the tested extracts, the ethanol extract of the clove buds showed remarkable scaven-ging activity, as compared with synthetic antioxidants such as butylated hydroxyl toluene (BHT). The ethanol extract of clove showed remarkable hepatoprotective activity against paracetamol-induced liver injury in female rats.