The use of microbes in culture of harpacticoid copepod (Tigriopus japonicus Mori) for suppression of Vibrio and enhancement of population growth, enzyme activity and microbial longevity

This study aimed to evaluate the effects of four potential microbial strains, consisting of Candida parapsilosis, Pseudoalteromonas flavipulchra, Lactobacillus sakei, and Bacillus natto, on the suppression of Vibrio and the increase of population growth and enzyme activity in the copepod Tigriopus japonicus. Five treatments were set up, including four experimental groups and a control, each with four replicates. For each strain a concentration 108CFU/mL−1 was applied. The results demonstrated that the use of L. sakei and B. natto, besides suppression of Vibrio, could increase the population growth and enzyme activity in copepods. The longevity of B. natto was recorded as the best in long-term inoculation in a way that after 8 days of copepod starvation, the count of B. natto after a significant decrease first, increased again. The findings showed that B. natto appears to be a promising bacterial strain for the copepod T. japonicus in the suppression of Vibrio and also in increasing the population growth, enzyme activity, and long-term inoculation potential.