Activity of Eugenia jambolana, an ethnomedical plant, against drug-resistant bacteria.

Seeds of Eugenia jambolana Lam. (Myrtaceae) are used by many tribes in India to treat diarrhea and dysentery. The crude extracts of seeds of this plant demonstrated zones of inhibition in the range of 14- 21 mm against the isolated beta-lactamase-producing drug-resistant bacteria. The methanol extract showed promising antibacterial activity which was subjected to fractionation. The effective fraction (F2) showed a minimum inhibitory concentration (MIC) ranging from 31.75 to 62.5 microg/mL. Phytochemical analysis and thin layer chromatography of the most promising fraction showed the presence of saponin as the active phytoconstituent. The active fraction was further tested for its in vitro hemolytic activity in sheep and human erythrocytes and no hemolysis was seen. Thus, the use of this plant by tribals to treat bacterial infections has some scientific basis.