Ecology, Environment and Conservation Paper

ANTIOXIDANT, ANTIMICROBIAL, AND PHYTOCHEMCIAL ASSESSMENT OF TEPHROSIA PURPUREA (L.) PERS. EXTRACTS

A.S. Rao and S.S. Yadav

Abstract

Tephrosia purpurea is a traditional herbal medicine used in impotency, asthma, dyspepsia, hemorrhoids, gonorrhea, rheumatism, enlargement of kidney and spleen. The present study deals with the in vitro evaluation of antioxidant, antimicrobial activities and phytochemical profiling of methanolic and Ethanolic leaf extracts of T. purpurea. Antioxidant activity was analyzed by 2,2’-azino-bis(3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) and -diphenyl--picrylhydrazyl (DPPH) assays while antimicrobial activity was evaluated by disc diffusion assay and Minimum Inhibitory Concentration against four bacteria and two fungi. Extracts were subjected to phytochemical profiling utilizing Fourier Transform Infrared Spectroscopy and Liquid Chromatography- Mass Spectrometry. Both the extracts showed considerable free radical scavenging activity with IC50 value of 78.7, 49.7 and 65.38, 55.38 μg/ml against DPPH and ABTS, respectively. The extracts exhibited both antibacterial and antifungal activities against the tested microorganisms however Staphylococcus aureus and Bacillus subtilis were the most susceptible bacteria towards the extracts. The extracts showed concentration dependent inhibition of microorganisms. The LC-MS analysis identified 37 phyto compounds in both the extracts of which 5-Methyl-2-[5-(2-methyl-benzooxazol-7-yl)-1H-pyrazol-3-yl]- Phenol, 3b,4,5,6,7,7a,9,10,11,12-Decahydrobenzo[b] fluoranthene and N-(3-Amino-1,4-dioxo-1,4- dihydronaphthalen-2-yl)-N-phenylacetamide were reported for the first time from the plant. FTIR data revealed the presence of several phytocompound classes, notably flavonoids, saponins, glycosides, phenolics, steroids and tannins. This baseline study is a notable step towards the exploration of T. purpurea leaves as an economical natural source of broad-spectrum antimicrobial and antioxidant agents.