The Influences of Aerobic and Anaerobic Conditions on PHB and Glycerin Yields in the Process of Lignin Degradation by Pseudomonas stutzeri P156
The effects of aerobic and anaerobic conditions on polyhydroxybutyrate (PHB) and glycerin yields during the course of lignin degradation were studied with Pseudomonas stutzeri P156. The lignin degradation rate was 22.5% and 15%, respectively, under aerobic and anaerobic condition. However, the gradation rate/biomass (YL/X) was nearly no differences that diversified from 0.9% to 3%. In addition, the maximal anaerobic yield of PHB and glycerin yield was 0.42 g/g and 56.3 ug/ml, which was 176.6% and 36.7% higher than that under aerobic condition, respectively. Interestingly to point out, anaerobic lignin degradation rate was decreased by 33.3% relative to the aerobic one, but lignin content did decreased by 15% at the cost of higher yields of PHB and glycerin, which suggested biosyntheses of PHB and glycerin could balance the redox potential under anaerobic condition, facilitate lignin degradation by Pseudomonas stutzeri P156, persistently, and meet the process demands of straw-based anaerobic methane fermentation.