Separation and identification of a hydrogen-producing acetogens strain ZR-1 and its acetic production characters

Abstract:

A hydrogen-producing acetogen strain ZR-1 was isolated from organic wastewater sludge by applying modified Hungate anaerobic method. According to morphological observation, physiologicalbiochemical characteristics and homology analysis of 16S rRNA gene sequence, the strain was identified as a genus of Clostridium glycolicum. The effects of temperature, pH, optimum substrate and metal ions on its productivity of acetic acid in anaerobic conditions were investigated and then optimized by uniform tests. The results indicated that the optimun temperature and initial pH of culture media for strain ZR-1 were 37 °C, 8.5, and it′s optimum substrate was butyrate. Supply of Mn²⁺ in culture medium can promote acetic acid production of ZR-1. At optimum cultivation conditions, the conversion rate of butyrate reached 12.7% and the content of H₂ was up to 28.73%.

Key words:Anaerobic digestion, Hydrogen-producing acetogen, Identify, Acetic acid production characteristics