ANTIMICROBIAL ACTIVITY OF PSIDIUM GUAJAVA AND MANILKARA ZAPOTA AGAINST HUMAN PATHOGENIC BACTERIA

Natural drugs are boom to mankind. They have few side effects as compared to allopathic medicines. Psidium guajava, is an important food crop and medicinal plant in tropical and subtropical countries is widely used like food and in folk medicine around of the world. Psidium guajava linked with the antioxidant, hepatoprotective, anti-allergy, antimicrobial, antigenotoxic, antiplasmodial, cytotoxic, antispasmodic, cardio active, anti-cough, antidiabetic, anti-inflammatory and anti-nociceptive activities and also used as hypoglycemic agent. Decoction of the bark used for diarrhoea and fever of Manilkara zapota. It contains linoleic acid, oleic acid, unsaturated fatty acids, linoleic acid, tannins, flavonoids. Crude extract of Manilkara zapota and Psidium guajava showed anti-microbial activity against gram positive Bacillus subtilis, Staphylococcus aureus and gram negative Escherichia coli, Salmonella typhii. The alcoholic fractions of leaves of Psidium guajava and Manilkara zapota were taken. The concentrations of leaf extract are made and evaluated for antimicrobial activity. DMSO is used as standard for antimicrobial assay. Highest zone of inhibition seen on the concentration of (0:2) and (0.4:1.6 ) for all the micro-organisms i.e. for Bacillus subtilis 19.5mm, for Staphylococcus aureus 17.8mm, for Escherichia coli 14.3mm, for Salmonella typhii 14.6mm for 0.4:1.6 concentration and the zone of inhibition of standard was found to be 18.1mm. This antimicrobial activity of Manilkara zapota and Psidium guajava on Escherichia coli, Salmonella typhii and Bacillus subtilis, Staphylococcus aureus suggest that it has anti-microbial activity. This study provides significant insights into the therapeutic effect of Manilkara zapota and Psidium guajava on gram positive and negative microbes and opens the way for further studies on identification of novel anti-microbial targets of Manilkara zapota and Psidium guajava.