Abstract: Six kinds of extraction methods were used to obtain effective components from the Chinese herb, including water extraction, microwave extraction, 60% acetone extraction, ethanol extraction (95%, 70% and 45% ethanol). The bacterial growth inhibition test in vitro was performed to evaluate bacteriostasis of the six kinds of extracts. The acute toxicity and maximal tolerance test on the water extract of the herb was implemented in mice. Anti-inflammatory effect of the water extract of Oroxylum indicum was observed by the ear edema induced by xylene in mice. The results showed that the six extracts of Oroxylum indicum had significant antibacterial actions on chicken Escherichia coli and Staphylococcus aureus, particularly 95% ethanol extract revealed highly sensitive to the two germs. The water extract of Oroxylum indicum was safe for animals from the findings of toxicological test and the MLD of water extract of Oroxylum indicum was 150 g/kg body weight by intragastric infuse in mice. The water extract of Oroxylum indicum had obvious anti-inflammatory effects by lowering ear swell in mice; the product also exhibited an immune suppressive action by decreasing spleen indices in mice.

Key words: Oroxylum indicum; antibacterial activity; anti-inflammatory activity