DISTRIBUTION OF POLY(3-HYDROXYBUTYRATE)-DEGRADING ANAEROBIC-BACTERIA

In order to elucidate anaerobic biodegradation of poly(3-hydroxybutyrate) (PHB), the degradation in anaerobic enrichment cultures inoculated with many environmental samples and the distribution of PHB-degrading anaerobic bacteria were investigated. Strict anaerobic enrichment cultures containing fibrous PHB were inoculated with 102 samples which were collected from 17 sampling points of the southern part of Ibaraki prefecture and the northern part of Chiba prefecture. In 61 enrichment cultures, the fibrous PHBs were disintegrated into powder, and decreases in the powder volume were observed. Analysis of the residual PHB, culture broth, and gaseous components indicated that PHB was degraded by the anaerobic bacterial attack. The accumulation of some volatile fatty acids as main fermentation products suppressed the bacterial degradation. The PHB-degrading anaerobic bacteria distributed widely in environment, particularly, in anaerobic bottom sediments.