Anticancer and antioxidant potential of pentacyclic triterpenoids isolated from C. carandas a medicinally important plant

Carissa carandas Linn, an important medicinal plant was used for the isolation of potent bioactive compounds from its leaves. C. carandas leaf material was shade dried and macerated in solvents such as hexane, chloroform, ethyl acetate and methanol and then concentrated using a rotary vacuum evaporator. FRAP, DPPH and the reducing power assays were used to measure the antioxidant activity. Isolation and purification of compounds using column chromatography followed by spectral analysis was done for identification. Of the four solvents used hexane, chloroform, ethyl acetate and methanol, the antioxidant potential of the methanol extract of C. carandas exhibited high DPPH (76.22μg/mL), FRAP (46.00μg/mL) and reducing power (81.83μg/mL) activities respectively. Gradient elution, followed by structural analysis using UV, IR and NMR spectral studies, resulted in the isolation of six triterpenoids, namely β-sitosterol and stigmasterol, lupeol, betulin, betulinic acid, oleanolic acid and methoxy urosolic acid. A comparative antioxidant activity of the isolated triterpenoids revealed the superiority of methoxy urosolic acid over the other triterpenes. Methoxy urosolate also exhibited anti-inflammatory (41.05%), cytotoxic (83.24%) and apoptotic potential against the lung cancer cell line A549. Of the four extracts, methanol extract exhibited the maximum antioxidant activity.