Inhibitory effect of Vibrio alginolyticus on the growth of V. harveyi

Abstract

One strain (NICA 1031) of Vibrio alginolyticus was screened from 50 strains of normal bacterial flora isolated from rearing water in Penaeus monodon hatchery based on its inhibitory activity against the growth of 5 strains Vibrio harveyi. The inhibitory effects of V. alginolyticus NICA 1031 on the growth of a V. harveyi strain were investigated by concomitant incubation of the two bacteria in artificial sea water under different conditions by monitoring colony forming unit of V. harveyi on BTB teepol agar. The inhibitory effect of V. alginolyticus against the strain of V. harveyi was higher in the sea water at 10 ppt of salinity than in those at 20 and 30 ppt. Results also showed that the higher inhibitory effect was revealed at 30-37°C than at 25°C and at pH 8.5 than pH 7.5 and 9.0.