Degradation of Polyvinyl Alcohol by a Mixed Microbial Culture Isolated from Paper Mill Treatment

Mixed microbial culture from paper mill treatment system was enriched on polyvinyl alcohol (PVA) medium and its PVA biodegradation capacity was investigated as a function of change in the initial pH values and PVA concentrations. The optimum pH value at 0.75 gl^-1 initial PVA concentration was determined to be 8. PVA biodegradation by mixed microbial culture was investigated at the range of 0.68 – 15.5 gl^-1 initial PVA concentrations. The mixed microbial culture was found to degrade within 5 days 98.6–88.5% of the initial PVA levels which ranged from 0.68 to 1.14 gl^-1. The mixed microbial culture was found to remove more than 90% of the initial PVA concentrations, within the range of 3.13 to 6.64 gl^-1 in 16–25 days of incubation at 35 °C.