Enhanced bio-hydrogen production from protein wastewater by altering protein structure and amino acids acidification type.
Enhanced bio-hydrogen production from protein wastewater by altering protein structure and amino acids acidification type via pH control was investigated. The hydrogen production reached 205.2 mL/g-protein when protein wastewater was pretreated at pH 12 and then fermented at pH 10. The mechanism studies showed that pH 12 pretreatment significantly enhanced protein bio-hydrolysis during the subsequent fermentation stage as it caused the unfolding of protein, damaged the protein hydrogen bonding networks, and destroyed the disulfide bridges, which increased the susceptibility of protein to protease. Moreover, pH 10 fermentation produced more acetic but less propionic acid during the anaerobic fermentation of amino acids, which was consistent with the theory of fermentation type affecting hydrogen production. Further analyses of the critical enzymes, genes, and microorganisms indicated that the activity and abundance of hydrogen producing bacteria in the pH 10 fermentation reactor were greater than those in the control.
State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
Naidong
N
Xiao
State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
Yinguang
Y
Chen
State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
Aihui
A
Chen
State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
Leiyu
L
Feng
D019342:Acetic Acid / Q000737:chemistry; D000596:Amino Acids / Q000737:chemistry; D000693:Anaerobiosis / Q000502:physiology; D001419:Bacteria / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology; D005285:Fermentation / Q000502:physiology*; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D011422:Propionates / Q000737:chemistry; D058767:Protein Unfolding; D011506:Proteins / Q000378:metabolism / Q000648:ultrastructure; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*
D019342:Acetic Acid; D000596:Amino Acids; D006859:Hydrogen; D011422:Propionates; D011506:Proteins; D062065:Wastewater; C029658:propionic acid