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 po ly(ether-ester) for bioabsorbable sutures, in natural environments was firs t revealed. Many kinds of PPDO-degrading microorganisms were found to be di stributed widely in natural environments. Twelve PPDO-degrading strains wer e isolated. From phylogenetic analysis based on 16S rRNA gene sequences, th e isolated PPDO-degrading strains were found to belong to the alpha and sub division of the class Proteobacteria and the class Actinobacteria. To clari fy the microbial degradability of PPDO, the degradation was investigated in pure cultures. The degradation by strain 3-1-a resulted in the rapid decom position and dissolution of high molecular weight PPDO, and the accumulatio n of acids as degradation products in culture medium. From HPLC and NR IR a nalyses? 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 Elsevie r Science Ltd. All rights reserved.