Estimation of camptothecin and pharmacological evaluation of Ophiorrhiza prostrata D. Don and Ophiorrhiza mungos L.

Abstract

ObjectiveTo carry out the qualitative and quantitative evaluation of camptothecin, estimation of total phenolic compounds and evaluation of in vitro antioxidant activity and cytotoxic activity of Ophiorrhiza prostrata and Ophiorrhiza mungos. MethodsDirect Analysis in Real Time- Mass Spectrometry (DART-MS) was employed for the detection of camptothecin in the Ophiorrhiza species, while high performance thin layer chromatography (HPTLC) was used for the estimation of camptothecin. Total phenolic compounds were estimated by modified Folins-Ciocalteu's reagent method. Antioxidant activity was evaluated through DPPH radical, hydroxyl radical, superoxide radical scavenging assays and reducing power assay. The cytotoxicity evaluation was performed using MTT assay on MCF-7 cell lines. ResultsThe presence of camptothecin was confirmed in both the species by the [M++H] peak at 349 by DART-MS analysis. Camptothecin content was estimated as 1.47 μg/gm (dry wt) in O. prostrata and 188.60 μg/gm (dry wt) in O. mungos using HPTLC method. The moderate in vitro antioxidant activities of the methanol extracts corroborates with the low content of phenolic compounds in O. prostrata (9.88 GAE mg/g) and O. mungos (12.73 GAE mg/g). The methanol extract of O. prostrata exhibited remarkable cytotoxicity on human breast cancer cell lines (MCF-7), with IC50 value 1.10μg/mL compared to O. mungos (3.48μg/mL) and standard camptothecin (3.51μg/mL). ConclusionsThe application of DART-MS proved to be a simple and rapid technique for the detection of camptothecin in Ophiorrhiza species. The higher cytotoxicity for O. prostrata, despite the low content of camptothecin suggests the presence of other potential cytotoxic compounds in O. prostrata.