[Show abstract][Hide abstract] ABSTRACT: Further investigation of the methanol extract of the Egyptian Red Sea soft coral, Heteroxenia ghardaqensis (Family Xeniidae), led to the isolation of a new hydroxymethyl diacylglycerol namely, 1-(11’-hydroxymethyl-hexadecanoyl)-2-pentadecanoyl-3-propanol (1). The structure elucidation of the compound was deduced by 1D and 2D NMR as well as FAB-MS. Compound 1 as well as the methanol extract showed moderate antimicrobial activities against gram positive bacteria (Micrococcus luteus B-287), gram-negative bacteria, Klebsiella pneumonia, and fungi, Candida albicans ATCC 10321.
[Show abstract][Hide abstract] ABSTRACT: 2-Amino-3-cyanopyridine is a simple precursor for the synthesis of analogues of Egyptian natural products visnagin and khellin. Fused pyrido[2,3-d]pyrimidines were prepared under mild reaction conditions. The detailed syntheses and spectroscopic data of the synthesised compounds are reported. Some isolated compounds show antibacterial and antifungal activity.
[Show abstract][Hide abstract] ABSTRACT: Cynara scolymus L. (Asteraseae) (artichoke) is commonly eaten as a vegetable; its leaves are frequently used in folk medicine in the treatment of hepatitis, hyperlipidaemia, obesity and dyspeptic disorders. The purpose of this study is to determine the chemical composition of the volatile oil and alcoholic extract of artichoke head scales. In addition, the role of the methanol extract as an anti-ulcer agent against ethanol-induced gastric ulcer in rats was evaluated.
Six flavonoids and one phenolic acid were obtained from the methanol extract. Also, 37 compounds were identified in the volatile oil, the majority including mono- and sesquiterpenes. The artichoke extracts (200 and 400 mg kg−1) significantly (P < 0.05) reduced the ulcer index (55.33% and 72.14% inhibition). Histopathological examination of rat stomachs demonstrated that artichoke induced an increase in gastric mucus production, and a reduction of the depth and severity of mucosal lesions. Artichoke dose-dependently reduced the elevated ethanol gastric malonylaldehyde, and reduced glutathione levels and catalase activity. These results suggest that the head scales of artichoke possess potential anti-ulcer activity.
The present paper describes the identification of volatile oil for the first time along with the isolation and identification of the constituents of the methanol extract. Moreover, the high anti-ulcerogenic potential of scales of C. scolymus heads was established here for the first time.
Journal of the Science of Food and Agriculture 08/2013; 93(10). DOI:10.1002/jsfa.6065 · 1.71 Impact Factor
[Show abstract][Hide abstract] 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.
[Show abstract][Hide abstract] ABSTRACT: The methanolic extract of the leaves of Cassia roxburghii DC., was investigated for its anthraquinone glycosides and antioxidant activity. Two new anthraquinone glycosides named emodin 1-O-β-d-glucopyranosyl-(1→2)-glucopyranoside (1) and aloemodin 8-O-β-d-glucopyranosyl-(1→6)-glucopyranoside (2) along with aloemodin 8-O-β-d-glucopyranoside (3), emodin (4), aloemodin (5) and one flavonoid, quercetin-3-O-α-l-rhamnopyranoside, were isolated from the leaves of C. roxburghii. Structures of the isolated compounds were established by UV, HRESI-MS, and 1D/2D (1)H/(13)C NMR spectroscopy. 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 10/2012; 360:47-51. DOI:10.1016/j.carres.2012.07.020 · 1.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Chemical investigation of the chloroform extract of the Egyptian Red Sea soft coral, Heteroxenia ghardaqensis (Family Xeniidae), led to the isolation of three gorgostane derivatives, namely gorgosten-5(E)-3β-ol (1), gorgostan-3β,5α,6β, 11α-tetraol (sarcoaldosterol A) (2) and gorgostan-3β,5α,6β-triol-11α-acetate (3). To our knowledge, sterol 3 is reported in this article for the first time. The structure elucidation of these compounds was deduced by 1-D and 2-D NMR as well as ESIMS. Sterol 1 showed moderate activity as growth inhibitor of human colon tumour cell lines.
Natural product research 09/2012; 27(14). DOI:10.1080/14786419.2012.724417 · 0.92 Impact Factor
[Show abstract][Hide abstract] 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. DOI:10.1016/j.carres.2010.11.007 · 1.93 Impact Factor
[Show abstract][Hide abstract] 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 09/2008; 20(5):452-456. DOI:10.1080/10412905.2008.9700057 · 0.79 Impact Factor