Isolation and Characterization of Phytoconstitutents from Achyranthes Asperal with Reference to Antioxidant Activity

Abstract

Achyranthes aspera is a well known and a potential herb for Ayurvedic medicine. It is used as a medicinal plant since ancient time. It is a very rich source of terpenoids, saponins, alkaloids etc. Literature shows that plant has very good antioxidant potential; also it shows antimicrobial, anticancer, antidiabetic and many more pharmacological activities. There are many constituents which are reported from Achyranthes aspera, but still further detailed investigation is needed for identification of complete chemical profile of the plant. So, this research work is focusing on isolation of phytoconstituents from plant and its identification by various spectroscopic methods like IR, Mass, and Nuclear Magnetic Resonance spectroscopy and to study its antioxidant potential. Standardization of plant of A. aspera was done by morphological study, microscopical study of powder materials, phytochemical screening for presence of active constituents, swelling and foaming index, physicochemical parameter like ash values, extractive values and loss on drying. Extract of A. aspera was prepared by soxhlet with methanol for 8 hrs. The methanolic crude extract was loaded in column and isolation was carried out by vacuum assisted column chromatography. Seven pure compounds aa01 to aa07 were isolated. FTIR, MASS, 1H-NMR, 13C-NMR spectrum of isolated compounds were recorded for identification and characterization. Probable structures of isolated compounds were predicted by their spectral data. HPTLC methods were developed for routine quantification of aa04, aa07 and oleanolic acid as phytoconstituents for A. aspera and the methods were further validated in terms of linearity, precision and accuracy. Methods for quantification of aa03, ecdysterone and oleanolic acid were also developed from extract. Compounds aa02 and aa04 were proved as ecdysterone by comparing spectral data and UV overlay spectra. Antioxidant potential of isolated compounds and methanolic extract was evaluated. In conclusion, data suggested that compound aa07 and methanolic extract of plant have antioxidant potential. IC50 value of aa07 and methanolic extract for antioxidant scavenging was found to be 11.827±0.23μg/ml and 14.489±0.47μg/ml respectively, indicate that the plant exhibits the anti oxidant potential due to compound aa07.