Lipase-producing Marine Actinomycetes Having Potential to Degrade PET Film

Abstract Currently, the study and the development of plastic degradation are receiving great attention since it could potentially be applied to plastic degradation. Owing to its environmentally benign nature, the enzymatic process of plastic degradation is highly desired. Polyethylene terephthalate (PET) is one of the most common plastic materials. The degradation of PET was possible by the treatment of the three hydrolases, namely cutinase, lipase, and esterase. On the other hand, marine actinomycetes, which are commonly found to associate with other organisms such as a sponge or residing in a unique environment such as marine sediment, could be a great source of valuable metabolites and enzymes. For that reason, in this study, six isolates of marine actinomycetes showing lipase activity were tested for PET-film degradation. The PET-film degradation was performed by incubating the isolates in a liquid media supplemented with PET films for 14 days. The resulting PET films were then subjected to XRD, FTIR, and SEM analysis. Despite of the decrease in crystallinity of PET-film which was only observed in treatment with isolate BLC 17-1, the FTIR analysis revealed that all absorbances, which are related to PET functionalities, were reduced. Further analysis by SEM showed that the surface of PET films treated with isolates was damaged, indicating degradation of the films. According to the results, it is concluded that the six isolates of marine actinomycetes have the potential to be applied to PET-film degradation.