Antitubercular Activity and Isolation of Chemical Constituents from plant Vitex negundo Linn.

Tuberculosis still remains a leading cause of death in the world. Currently considerable interest in natural products and their derivatives in the area of drug research for multidrug resistant tuberculosis (MDR-TB). The present investigation focused on identification, isolation, characterization of lead constituents and to determine the antitubercular activity of their enriched fractions and isolated compounds by Nitrate reductase assay (NRA) method. Leaves extracted with ethanol by soxhlet extraction and ethanol extract separated in petroleum ether, chloroform and methanol by separating funnel and fractionated by column chromatography. Ethanol extract, petroleum ether and chloroform fraction showed antitubercular activity at 150 µg/mL. Isolated HEA-2, CM-20 and CM-24 showed MIC at 100 while PE-34 at 50 and 100 µg/mL. β-sitosterol content in chloroform and petroleum ether fractions was calculated by using HPTLC. Pet. ether and chloroform fractions of ethanol extract which contains betulinic acid, ursolic acid and β -sitosterol shows anti- TB activity. HPTLC, IR, 1 H NMR and GC-MS study of isolated PE-34 gave satisfactory results for confirmation of the structure as ursolic acid with significant antitubercular potential.