Enhancement of Fermentative Hydrogen Production from Beverage Wastewater via Bioaugmentation and Statistical Optimization

Abstract

In this study an attempt was made to enhance anaerobic hydrogen production from beverage wastewater (BWW) by augmenting anaerobic enriched mixed cultures (EMC) with facultative Enterobacteriaceae strains (E. Coli XL1-BLUE, Enterobacter cloacae) under mesophilic temperature 37°C, pH 5.5 and substrate concentration of 10 gglucose equivalent /L. Among the bioaugmented cultures, E. cloacae+EMC led to the peak hydrogen production rate (HPR) of 2250 mL/L-d. Furthermore, the variables substrate concentration and pH was statistically optimized using response surface methodology (RSM). Results show that the predicted maximum HPR of 3096 mL/L-d was achieved under optimal opera- tion conditions: substrate concentration 25.6 g glucose equivalent /L and pH 5.7. Verification experimental results showed HPR of 3044 mL/L-d, reveals that predicted results were closure with the experimental data and proved experimental design optimization processes are more feasible techniques for biohydrogen production. PCR-DGGE analysis indicates that Clos- tridium sp. and Enterobacter sp. were appeared under optimal conditions.