A Performance Comparison of Three Amino Acid Additives in the Process of Photo-Fermentative Biohydrogen Production with Corn Straw

The growth and metabolism of photosynthetic bacteria play a significant role in the efficiency of substrate and energy conversion in photo-fermentation biohydrogen production (PFHP). In this paper, the influence of different concentrations of L-alanine (0.3–1.2 g/L), L-leucine (0.6–1.5 g/L), and L-serine (1–2.5 g/L) on the PFHP and microbial metabolism were investigated. The results showed that sole additions of L-alanine at 0.6 g/L, L-leucine at 0.9 g/L, and L-serine at 1.5 g/L to the PFHP could enhance the cumulative biohydrogen production to 260 ± 4.01 mL (39.04% increase), 267 ± 4.27 mL (42.78% increase), and 248 ± 3.97 mL (32.62% increase), respectively. An analysis of the scatter matrix plots indicated that three amino acid additives play a key role in increasing hydrogen production. This study helps to further explore the effect of amino acid-based additives on PFHP.