Aliphatic polyester biodegradation by coral-associated bacteria from Karimunjawa Marine National Park, Java Sea

Abstract

Plastic waste is one of the environmental pollutants that is difficult to degrade. The spread of plastic waste is almost everywhere even in the ocean, especially in coral reef ecosystem. Non-degradable plastic like polyethylene, polypropylene, and polystyrene begins to be partially replaced with biodegradable plastic materials (i.e polycaprolactone) as a strategy to reduce non-degradable polymer materials. Hence, this study aims is to find the potential of polycaprolactone biodegradation from coral associated-bacteria from Karimunjawa National Park. Coral samples were isolated in July 2020 from areas with influence by anthropogenic. Bacterial isolates were screened using tributyrin and polycaprolactone as substrates to reveal potential polyester degradation enzymes. The result obtained only one active bacterial isolate that potential to degrade polycaprolactone from a total of 18 isolates bacteria. LBB 2 showed that strain can degrade polycaprolactone by 8 days incubation period with 4 days in room temperature and 4 days in a 4°C incubation room. Bacterial identification by 16S rRNA sequences showed that strain LBB 2 refers to the bacteria Bacillus subtilis. The similarity level in the database of National Center Biotechnology Information by 99.45%. These results prove that associated bacteria from stony coral might play a role in degrading aliphatic polyesters.