• Natural Product Sciences
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• v.13 no.2
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• pp.140-143
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• 2007

Investigation of the chloroform soluble fraction of the red alga Liagora farinosa, collected from Hurghada at the Red Sea resulted in the isolation of three compounds; a nucleoside (thymidine) and two glycosides (methyl-${\beta}$-D-xylopyranoside and glycerol-2-${\alpha}$-D-glucopyranoside). The structures of the isolated compounds were established on the basis of different spectroscopic techniques as well as comparison with the previously published data. This is the first report for the isolation of the three compounds fron red algae; moreover, the compounds were examined for their antioxidant activity and showed variable activity.

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.407-411
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• 2007

Regulation of ${\beta}-xylosidase$ synthesis in Paenibacillus sp. DC-22 was studied to optimize the enzyme production. ${\beta}-Xylosidase$ synthesis of the Paenibacillus sp. DG-22 was observed to be regulated by carbon sources present in culture media. The synthesis of ${\beta}-xylosidase$ was induced by xylan and methyl ${\beta}-D-xylopyranoside$ (${\beta}MeXyl$) but slightly repressed by readily metabolizable monosaccharides. ${\beta}MeXyl$ was found to be the best substrate for the induction of ${\beta}$-xylosidase and the most effective induction was obtained at a concentration of 10 mg/ml. ${\beta}-Xylosidase$ production showed a cell growth associated profile with the maximum amount formed during the late exponential phase of growth. The presence of glucose and xylose decreased the level of ${\beta}-xylosidase$ activity indicating that its production was subjected to a form of carbon catabolite repression. SDS-PAGE and zymogram techniques demonstrated the induction by ${\beta}MeXyl$ and revealed the presence of one ${\beta}-xylosidase$ of approximately 80 kDa.

• Natural Product Sciences
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• v.19 no.3
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• pp.215-220
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• 2013

Three C-glucosyl flavones (1 - 3), one xanthone (4), and four flavanonols (5 - 8) were isolated by various chromatographic methods from the leaves and stems of Desmodium caudatum (Thunb.) DC. Chemical structures of these compounds were elucidated by 1D and 2D NMR and mass spectroscopy. The compounds were identified as swertisin (1), spinosin (2), 7-methyl-apigenin-6-C-${\beta}$-glucopyranosyl-2"-O-${\beta}$-D-xylopyranoside (3), 1,3,5,6-tetrahydroxyxanthone (4), yokovanol (5), aromadendrin (6), 2'-hydroxy yokovanol (7), and 2'-hydroxy neophellamuretin (8). Compounds 2 - 4 were first isolated from D. caudatum, as well as the spectroscopic data for compound 3.

• Natural Product Sciences
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• v.17 no.2
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• pp.80-84
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• 2011

Five known compounds, cimigenol (1), 25-O-acetylcimigenol (2), cimigenol 3-O-${\beta}$-D-xylopyranoside (3), ferulic acid methyl ester (4), and visnagin (5), were isolated from Cimicifugae Rhizoma (Ranunculaceae). The chemical structures of these compounds were determined on the basis of spectroscopic analyses including 2D NMR. Compounds 1 - 5 were evaluated for their cytotoxic activity against the HL-60, MCF-7, and A549 cancer cell lines in in vitro. Among them, compounds 4 and 5 showed moderate inhibitory activity against HL-60 cancer cell lines with $IC_{50}$ values of 24.8 and 18.1 ${\mu}M$, respectively.