Evaluation of antimicrobial activity of extracts of Tibouchina candolleana (melastomataceae), isolated compounds and semi-synthetic derivatives against endodontic bacteria

This work describes the phytochemical study of the extracts from aerial parts of Tibouchina candolleana as well as the evaluation of the antimicrobial activity of extracts, isolated compounds, and semi-synthetic derivatives of ursolic acid against endodontic bacteria. HRGC analysis of the n-hexane extract of T. candolleana allowed identification of b-amyrin, a-amyrin, and b-sitosterol as major constituents. The triterpenes ursolic acid and oleanolic acid were isolated from the methylene chloride extract and identified. In addition, the flavonoids luteolin and genistein were isolated from the ethanol extract and identified. The antimicrobial activity was investigated via determination of the minimum inhibitory concentration (MIC) using the broth microdilution method. Amongst the isolated compounds, ursolic acid was the most effective against the selected endodontic bacteria. As for the semi-synthetic ursolic acid derivatives, only the methyl ester derivative potentiated the activity against Bacteroides fragilis.

Flavonoids of retama raetam, and in vitro antitumor screening of two isoflavones

From the aerial parts of Retama raefam ten flavonoids were isolated and identified as saponarin, genistein 8-C-glucoside, genistein 5-O- methylether, genistein 5,4'-di-O-methylether, alpuminoisoflavone, ephedroidin, luteolin, apigenin and two new flavones, luteolin 4'-O- neohesperidoside and 5,4'-dihydroxy- [3",4''- dihydro- [3",4"-dihdroxy] -2",2"dimethylpyrano [5",6":7,8]-flavone[1]. In vitro antitumor screening of genistein-5-O-methylether and genistein-8-C-glucoside were carried out on sixty human tumor cell lines

Pharmacological activities of Genistein, an isoflavone from soy (Glycine max): part I--anti-cancer activity.

Phytoestrogens represent a family of plant compounds such as isoflavones, flavones and lignans. A variety of these plant compounds have been identified in various human body fluids. A wide range of commonly consumed foods contains appreciable amounts of these different phytoestrogens, viz. soy products are particularly good sources of isoflavones and lignans. Accumulating evidences from molecular and cellular biology experiments, animal studies, and to a limited extent, human clinical trials suggests that phytoestrogens may potentially confer health benefits related to various cancers and diseases such as cardiovascular disorder. The evidences reviewed here represent the beneficial effects of most potential and promising isoflavone, Genistein in various types of cancers.