Antibacterial Activity of Bauhinia sirindhorniae Extract Against Aeromonas hydrophila Isolated from Hybrid catfish

The studies on antibacterial activity of Bauhinia sirindhorniae extract, an indigenous plant of Nong Khai province, against Aeromonas hydrophila isolated hybrid catfish were assayed. Root, stem, leaves and flowers of B. sirindhorniae were extracted by acetone, ethanol 50 %, ethanol 95 % and methanol. In antibacterial screening performed by disc method was conducted. The results revealed that the highest activity against A. hydrophila, found in roots extract using acetone with an inhibition zone, was 20.33 ± 0.58 mm. The minimum inhibitory concentration (MIC) for B. sirindhorniae extracts were also determined by the broth dilution method. The lowest MIC value with high efficacy against A. hydrophila was 97.66 ppm which could be obtained from the root extract of B. sirindhorniae from acetone. The minimum bactericidal concentrations (MBC) of B. sirindhorniae extracts were also determined. The determination of MBC was not observed in any concentration of B. sirindhorniae extracts.