The phytochemical analysis of the ethyl acetate fraction of Arum palaestinum Boiss. (Araceae) led to the isolation and identification of a new polyhydroxy alkaloid compound; (S)-3,4,5-trihydroxy-1 H-pyrrol-2(5H)-one (1), and other five known compounds; caffeic acid (2), isoorientin (3), luteolin (4) and vicenin 11 (5), as well as the rare compound 3,6,8-trimethoxy, 5,7,3',4'-tetrahydroxy flavone (6). The structural elucidations of all the compounds were based on spectroscopic data (1H- and 13C-NMR, DEPT, HSQC, HMBC and NOE difference techniques) and comparison with literature data. Investigation of the antioxidant activity of the ethyl acetate fraction indicated its strong scavenging capacity for 1,1 -diphenyl-2-picrylhydrazyl (DPPH) radicals (SC50 3.1+/-0.82 microg/mL). Moreover, the treatment of different human cancer cell lines with the ethyl acetate fraction led to dose-dependant suppression in the proliferation of both breast carcinoma cells (MCF-7; IC50 59.09+/-4.1 microg/mL) and lymphoblastic leukemia cells (1301; IC50 53.1+/-2.9 microg/mL); however, it was found to have no effect on the growth of hepatocellular carcinoma cells (Hep G2).

The inhibitory activity of tanshinones from Salvia miltiorrhiza was tested on rat liver diacylglycerol acyltransferase (DGAT). Cryptotanshinone (1) and 15,16-dihydrotanshinone I (3) exhibited potent DGAT inhibitory activities dose-dependently with IC50 values of 10.5 microg/ml and 11.1 microg/ml. However, tanshinone IIA (2) and tanshinone I (4) showed very weak inhibition (IC50 value: > 250 microg/ml). A dihydrofuran moiety was seemed to be responsible for the stronger inhibitory activity.

A new acylated apigenin glucoside (apigenin-7-O-(6''-butyryl-beta-glucopyranoside) (1) was isolated from the methanolic extract of the leaves of Phyllanthus emblica L. (Euphorbiaceae) together with the known compounds; gallic acid (2), methyl gallate (3), 1,2,3,4,6-penta-O-galloylglucose (4) and luteolin-4'-O-neohesperiodoside (5). Their chemical structures were elucidated on the basis of spectroscopic studies ((1)H NMR, (13)C NMR, DEPT, HSQC, HMBC).

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