Cytotoxic potential of Anisochilus carnosus (L.f.) wall and estimation of luteolin content by HPLC

BACKGROUND Anisochilus carnosus (L.f.) wall (Lamiaceae), an annual herb which grows at high altitude is used extensively in folk medicine for the treatment of ailments such as gastric ulcer and skin diseases. The aim of our study was to evaluate the anticancer activity of different extracts of the leaves of A.carnosus. An attempt was also made to estimate the luteolin content in different extracts of Anisochilus carnosus by HPLC (High Performance Liquid Chromatography). METHODS In the current study, we explored the cytotoxic potential of petroleum ether, ethanolic and aqueous extracts of A.carnosus against breast adenocarcinoma cell line (BT-549), by in vitro MTT and SRB assay. We also detected the luteolin content in different extracts (ethanolic and aqueous) of A.carnosus by using HPLC as a tool of analysis. RESULTS The results demonstrate that petroleum ether and ethanolic extract of A.carnosus showed potent cytotoxic effect against BT-549 with an IC50 of 22.5 μg/ml (petroleum ether extract) and 87.24 μg/ml (ethanolic extract), by SRB assay, and 18.35 μg/ml (petroleum ether extract) and 58.64 μg/ml (ethanolic extract), by MTT assay. The aqueous extracts showed less cytotoxic effect with an IC50 of 211.26 μg/ml (by SRB assay) and 238.91 μg/ml (by MTT assay). HPLC results of luteolin content in various extracts using luteolin as the marker compound indicated the ethanol extract to contain the highest concentration of luteolin (0.372% w/w). The aqueous extract contained lower concentration of luteolin (0.282% w/w). CONCLUSION Our findings demonstrate that petroleum ether and ethanolic extract of A.carnosus shows promising anticancer activity and has the potential to be developed into a therapeutic option for the treatment of cancer.