PHYTOCHEMICAL INVESTIGATION AND ANTIMICROBIAL PROPERTIES OF LEAF EXTRACT OF Zehneria scabra

Abstract

All parts of Zehneria scabra are traditionally used for the treatments of different ailments. The present study was carried out to investigate phytochemicals and evaluate antimicrobial activities of the leaves of Zehneria scabra. The leaves of the plant were sequentially extracted with petroleum ether, chloroform/methanol (1:1) and methanol for 8 h using Soxhlet apparatus. Phytochemical screening tests of Zehneria scabra were performed on petroleum ether, chloroform/methanol (1:1) and methanol crude extracts. The petroleum ether extract of the plant showed the presence of steroids, carbohydrates, phenol and flavonoid. Similarly the chloroform/methanol (1:1) crude extracts of the plant showed the presence of alkaloid, tannins, terpenoids, flavonoid, carbohydrate and phenols. The methanol crude extract of the plant was found to contain flavonoids, tannins, terpenoids, alkaloid, saponins, phenols and glycosides from the tested phytochemicals. Hexane extract of the plant leaf was obtained using a Soxhlet apparatus and its constituents were determined by GC-MS. GC-MS profile revealed the presence of 4 compounds among which the constituents of leaf hexane extract includes N-(N-Lalanylglycyl) glycine (51.31%), Ethyl oxamate (20.03%), 2,5-dimethoxy-4- (methylsulfonyl) amphetamine (14.50%) and 4-methyl-2-hexanamine (14.16%) were considered as major constituents. The hexane extract, crude extracts, isolated pure compound and fractions of the leaves were tested for their antimicrobial activity and the highest activity was exhibited by volatile oil, petroleum ether, methanol and CHCl3/MeOH(1:1) extract against S.typhi, S.aureus, St. agalactiae and E.coli, respectively. The crude extracts of this plant also tested for their antitubercular activity by agar microdilution method. The pure compound, ZS-1, isolated from petroleum ether extract was with solvent ratio of toluene: ethyl acetate (4:1). The structure of this compound was established by UV-Vis, IR and NMR spectral data. Isolated pure compound exhibited medium antimicrobial activity against E. coli and having high activity against S.typhi. Thus the present study supported the traditional claims of the plant