Identification of bioactives from Astragalus chinensis L.f. and their antioxidant, anti-inflammatory and anti-proliferative effects.

This work was designed to obtain the valuable compounds with antioxidant, anti-proliferative and anti-inflammatory activities from Astragalus chinensis. Ethyl acetate fraction obtained from A. chinensis L.f. had significant antioxidant, anti-proliferative and anti-inflammatory activities. Subsequently, five single compounds were separated and purified, which were identified as formononetin (1), rhamnocitrin (2), calycosin (3), ß-daucosterol (4), rhamnocitrin-3-O-ß-d-glucoside (5). The results displayed that formononetin and rhamnocitrin exhibited significant cytotoxicity actions against tumor cell lines. Calycosin exerted the strongest anti-inflammatory effect of inhibition effects on NO production in macrophages.

Eclipta prostrata L. phytochemicals: isolation, structure elucidation, and their antitumor activity.

Eclipta prostrata L., (Asteraceae), is used in China for both food and medicine purposes. This research is concerned with the isolation and purification of phytochemical constituents from the aerial parts of E. prostrata, using gradient solvent fractionation, macroporous resin, silica gel, Sephadex LH-20 and ODS columns, and TLC analyses. Four fractions (water, 30% ethanol, 60% ethanol and 90% ethanol) were obtained. Four compounds, wedelolactone (I), eclalbasaponin I (II), luteolin (III) and luteolin-7-O-glucoside (IV) were purified and their structures were identified by the interpretation of spectroscopic analyses including MS, (1)H and (13)C NMR. Antitumor activities of extracts (total fraction), four fractions and the isolated compounds were assessed using hepatoma cell smmc-7721 as an in vitro assay system. The 30% ethanol fraction and eclalbasaponin I dose-dependently inhibited the proliferation of hepatoma cell smmc-7721 with IC(50) values of 74.2399 and 111.1703 µg/ml, respectively, more strongly compared with 5-fluorouracil positive control group with the IC(50) value of 195.3131 µg/ml. Antitumor activities of other fractions and compounds were lower than positive control. These results suggested that some specific compounds or extracts from E. prostrata are potential sources of natural anti-tumor materials and worthy of further study.

Antioxidative activities of medicinal plants from TCM.

As a natural antioxidant resource, traditional Chinese medicine (TCM) has been paid much more attentions than before. The studies on its antioxidative activity have also increased dramatically in recent years. Abundant studies on TCM show that some TCM can increase body's activity of antioxidant enzymes, enhance body's ability of scavenging free radicals and decrease the generation of lipid peroxide (LPO) and malondialdehyde (MDA) in the body etc. The action mechanism of TCM is closely related to its active constituents, including polysaccharides, quinines, flavonoids, saponins, alkaloids, terpenes, phenolic acids compounds and tannins etc. Through referring to related reports on TCM, in the last 20 years, this paper reviews literatures involved in antioxidation research on TCM. Antioxidative mechanism, functional property and application prospect of some active constituents with antioxidation in TCM are discussed.