In vitro antibacterial and antioxidant activities of alcoholic extract from the leaves of Podocarpus neriifolius D. Don

In the present investigation, the methanol leaves extract of Podocarpus neriifolius D. Don was assessed for antibacterial and antioxidant activities. The antibacterial action was evaluated through agar disc diffusion method against seven pathogenic and non-pathogenic bacterial strains at various concentrations and compared against the standard (kanamycin 30 µg/disc). The antioxidant activity of the extract was investigated by means of a variety of in vitro assays and results were compared with standard drugs. The experiment indicates that the extract was effective against all the organisms and highest effectiveness showed against Salmonella paratyphi at 1000 µg/disc concentration. It also exhibited significant antioxidant activity. The total phenolic content was 168.2±6.4 mg galic acid equivalents/g of extract. The reducing power of this extract increases with the raise of concentration and the value of IC50 of 1,1-diphenyl-2- picrylhydrazyl (DPPH). scavenging activity was 4.73 µg/ml (IC50) value of standard ascorbic acid is 5.99 µg/ml. The results provided that the studied plant might indeed be possible basis of natural antioxidant as well as antimicrobial agents. Key words: Podocarpus neriifolius, antioxidant, antibacterial, 1,1-diphenyl-2- picrylhydrazyl (DPPH), reducing power, total phenol.