Microbial degradation of poly(p-dioxanone) - I. Isolation of degrading microorganisms and microbial decomposition in pure culture

Microbial degradability of poly(p-dioxanone) (PPDO), which is known as a poly(ether-ester) for bioabsorbable sutures, in natural environments was first revealed. Many kinds of PPDO-degrading microorganisms were found to be distributed widely in natural environments. Twelve PPDO-degrading strains were isolated. From phylogenetic analysis based on 16S rRNA gene sequences, the isolated PPDO-degrading strains were found to belong to the alpha and subdivision of the class Proteobacteria and the class Actinobacteria. To clarify the microbial degradability of PPDO, the degradation was investigated in pure cultures. The degradation by strain 3-1-a resulted in the rapid decomposition and dissolution of high molecular weight PPDO, and the accumulation of acids as degradation products in culture medium. From HPLC and NR IR analyses? the products were confirmed to be dominated by monomeric acid. It was determined that the degrading strains merely hydrolyzed PPDO to soluble oligomeric acids, and did not substantially utilize them. (C) 2000 Elsevier Science Ltd. All rights reserved.