Degradation of polyvinyl alcohol by a novel bacterial strainStenotrophomonassp. SA21

In this study, polyvinyl alcohol (PVA)-degrading bacteria were screened from oil sludge using PVA as a sole source of carbon in the culture medium. A novel strain, SA21, was obtained and identified as a member of the Stenotrophomonas genus based on the analysis of a partial 16S rDNA nucleotide sequence, morphological and biochemical characteristics, and phylogenetic analysis. This Stenotrophomonas isolate had not previously been reported as a PVA-degrading bacterium. Stenotrophomonas sp. strain SA21 degraded 90% of the PVA present in the culture medium after 4 days. The effect of nitrogen sources on the production of PVA-degrading enzyme involved in the biodegradation process was significant, and the enzymatic activity reached 82 U/ml when ammonium nitrate or urea was used in the optimized medium. The information obtained in this study will provide a foundation for improving industrial wastewater treatment.Abbreviations: DCW: dry cell weight; FTIR: Fourier Transform Infrared Spectroscopy; NCBI: National Center for Biotechnology Information; PCR: polymerase chain reaction; PVA: polyvinyl alcohol; SEM: scanning electron microscope