Organic carbon recovery and photosynthetic bacteria population in an anaerobic membrane photo-bioreactor treating food processing wastewater.

Purple non-sulfur bacteria (PNSB) were cultivated by food industry wastewater in the anaerobic membrane photo-bioreactor. Organic removal and biomass production and characteristics were accomplished via an explicit examination of the long term performance of the photo-bioreactor fed with real wastewater. With the support of infra-red light transmitting filter, PNSB could survive and maintain in the system even under the continual fluctuations of influent wastewater characteristics. The average BOD and COD removal efficiencies were found at the moderate range of 51% and 58%, respectively. Observed photosynthetic biomass yield was 0.6g dried solid/g BOD with crude protein content of 0.41 g/g dried solid. Denaturing gradient gel electrophoretic analysis (DGGE) and 16S rDNA sequencing revealed the presence of Rhodopseudomonas palustris and significant changes in the photosynthetic bacterial community within the system.