Enhanced photo fermentative H2 production from cornstalk by acid-tolerant R. capsulatus mutation

Culture pH is very crucial to hydrogen production in the photo-fermentation process. Excessively low pH can directly affect cell growth and hydrogen production by changing bacterial physiological characteristics. Thus, screening acid-tolerant strains that can alleviate acid stress with enhanced hydrogen production is essential. In this work, an acid-tolerant mutant Rhodobacter capsulatus AT11 was isolated by transposon technology, and its photosynthetic characteristic under different initial pH values was investigated. The results indicated that the H2 yield of AT11 at initial pH of 5.5 was 4682.64 mL·L−1, which was 310.65