Aspergillus oryzae lipase-mediated in vitro enzymatic degradation of poly (2,2'-dimethyltrimethylene carbonate-co-ε-caprolactone)

The amino acid sequence and spatial structure of lipases from different sources often result in significant dif-ferences in the active sites, which exhibit differential activity when interacting with a particular polymer, as reflected in the rate of degradation of the polymer. The research of the degradation properties of enzymes for specific polymers can therefore be a helpful guide in production. In this study, a series of copolymer poly(2,2 '- dimethyltrimethylene carbonate-co-epsilon-caprolactone) P(DTC-co-CL) was prepared and the in vitro enzymatic degradation behavior of the resultant copolymers was performed in the lipase solutions (from Aspergillus oryzae, >= 100,000 U/g), and the effect of the CL content in composition on the degradation behavior of P(DTC-co-CL) was investigated. The results showed that lipase significantly can accelerate the degradation rate of P(DTC-co-CL), and the mass loss of P(DTC-co-CL) strongly depended on the CL content due to the prior cleavage of ester bonds under the catalysis activity of lipase enzymes. For the copolymers containing 85 mol% CL, 37.9% of mass loss and 75.2% remaining CL content were observed after degradation of 15 days. Samples with 75 mol% DTC content can maintain good dimensional stability after the degradation, indicating that the introduction of DTC was beneficial to maintain the morphology. The results showed that P(DTC-co-CL) had adjustable degra-dation properties and well form-stability, which was a promising candidate for biomedical applications.

Automated summary

The amino acid sequence and spatial structure of lipases from different sources often result in significant differences in the active sites, which exhibit differential activity when interacting with a particular polymer, as reflected in the rate of degradation of the polymer. Therefore, studying the degradation properties of enzymes for specific polymers can be a helpful guide in production.