Abstract

Bacillus is found not only in terrestrial and marine environments but also in the intestines of humans, animals, and marine species. Due to its ability to produce these valuable bioactive compounds, Bacillus is widely utilized as a key material for developing new probiotics. In an experiment using strains isolated from the intestines of sea cucumbers, the strains were tested for their ability to break down agar, alginic acid, carrageenan, cellulose, and starch-major polysaccharides in seaweed consumed by marine organisms-along with chitin. The results showed that all strains capable of degrading at least two of these macromolecules belonged to the genus Bacillus. Notably, B. proteolyticus strain SCT64 and B. halotolerans strain SCT118 demonstrated the ability to degrade all the tested macromolecules. Therefore, intestinal Bacillus strains derived from marine organisms, with their ability to produce various bioactive compounds, hold great potential as probiotics for sustainable aquaculture, particularly for farmed sea cucumbers, fish, and other marine species.

Keywords: Aquaculture; Intestinal microorganism; Maine Bacillus; Polysaccharides; Probiotics