Determination of in vitro antioxidant and UV-protecting activity of aqueous and ethanolic extracts from Galinsoga parviflora and Galinsoga quadriradiata herb.

Galinsoga species are used in folk medicine as anti-inflammatory agents and accelerators for wound healing. They also have reported antioxidant activity. We examined aqueous and ethanolic extracts derived from the Galinsoga herb as potential photoprotectors, as the role of reactive oxygen species (ROS) has implicated in skin damage. The extracts used in the study were standardized by determining the sum of flavonoids, and the amount of caffeic acid and its derivatives. The antioxidant activity of the extracts was evaluated by examining the scavenging of two radicals (O2(-) and H2O2) generated in cell-free systems. We also examined the effect on ROS generation by human skin fibroblasts after UV irradiation. In addition we determined the cytotoxicity of the extracts and their protective effect against damage caused by UV irradiation (MTT test, LDH release test and staining with annexine V-FITC/PI). Our findings show that the ethanolic extracts from the herb have cytotoxic effects, while the aqueous extracts from Galinsoga herb have protective activity, in part due to their ability to inhibit ROS generation. In the conclusion the aqueous extracts from the both tested species may be effective as photoprotectors.

Novel insight into qualitative standardization of Polygoni avicularis herba (Ph. Eur.).

Polygonum aviculare L. (Common Knotrgrass) (Polygonaceae Juss.) is an annual from which pharmacopoeial (Ph. Eur.) plant material Polygoni avicularis herba is obtained. Although its main active constituents are flavonoids and its standardization is based on their total content, no profound qualitative analysis has been performed, yet. The use of hyphenated analytical methods: UHPLC-DAD coupled with ion trap or time of flight mass detectors together with acidic hydrolysis products analysis allowed for a comprehensive determination of flavonoid composition. Among dominating compounds, myricetin, kaempferol, isorhamnetin and kaempferide glucuronides, which were not previously reported in P. avicularis herba, were discovered. The developed method can be used as a suitable tool for a more insightful, metabolome-based standardization of flavonoid rich pharmacopoeial plant material -P. avicularis herba.