The Evaluation of Marine Sponge–Associated Bacteria Microcapsule to Control Vibriosis in the Shrimp Culture

Abstract

The most frequent disease on vannamei shrimp is caused by Vibrio sp. bacterial infection. Vibrio sp. might cause a serious production loss in the shrimp culture, leading to larvae and mature stadium mortality at 50%. To date, vibriosis disease has yet to be controlled properly. Therefore, sponge-associated bacteria are used as an alternative to control vibriosis disease in shrimp. To maintain and protect the potential bacteria from unfavorable environmental influence, combining the ability of sponge-associated bacteria and encapsulation technology is necessary. This research aimed to evaluate the viability, shelf life, anti-vibrio activity, and structure characteristics under Scanning Electron Microscope (SEM) of Bacillus spp. microencapsulation using alginate, chitosan, as well as Arabic gum. The method of viability test used Total Plate Count (TPC) and to reconfirm the antibacterial test was conducted using plug agar method. The result indicates that the B. altitudinis PH.1 coated with chitosan show the highest viability at 1.8x108 CFU/ml after 14 days preserved in -20C. The moisture content of this treatment revealed 17% as the highest than the other treatment, therefore the predicted shelf life for chitosan coated reach 9.1 years. Furthermore, the antivibrio of B. altitudinis PH.1 show the strong activity with clear zone inhibition at 16.07 mm against Vibrio alginolyticus. The structure of B. altitudinis PH.1 under SEM observation was irregular shape and size. Therefore, this study found that chitosan could be an alternative source to preserve a potential bacterium using microencapsulation technology.