Improvement of hydrogen fermentation of galactose by combined inoculation strategy.
This study evaluated the feasibility of anaerobic hydrogen fermentation of galactose, a red algal biomass sugar, using individual and combined mixed culture inocula. Heat-treated (90°C, 30 min) samples of granular sludge (GS) and suspended digester sludge (SDS) were used as inoculum sources. The type of mixed culture inoculum played an important role in hydrogen production from galactose. Between two inocula, granular sludge showed higher hydrogen production rate (HPR) and hydrogen yield (HY) of 2.2 L H2/L-d and 1.09 mol H2/mol galactoseadded, respectively. Combined inoculation (GS + SDS) led to an elevated HPR and HY of 3.1 L H2/L-d and 1.28 mol H2/mol galactoseadded, respectively. Acetic and butyric acids are the major organic acids during fermentation. Quantitative polymerase chain reaction (qPCR) revealed that the mixed culture generated using the combined inoculation contained a higher cluster I Clostridium abundance than the culture produced using the single inoculum.
Department of Environmental Engineering, Daegu University, Gyeongsan, Gyeongbuk 38453, Republic of Korea; Center for Materials Cycles and Waste Management Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan; Sustainable Environmental Process Research Institute, Daegu University, Gyeongsan, Gyeongbuk 38453, Republic of Korea.
Periyasamy
P
Sivagurunathan
Department of Civil Engineering, Daegu University, Gyeongsan, Gyeongbuk 38453, Republic of Korea; Sustainable Environmental Process Research Institute, Daegu University, Gyeongsan, Gyeongbuk 38453, Republic of Korea.
Parthiban
P
Anburajan
Center for Materials Cycles and Waste Management Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan; Sustainable Environmental Process Research Institute, Daegu University, Gyeongsan, Gyeongbuk 38453, Republic of Korea.
Gopalakrishnan
G
Kumar
Department of Environmental Engineering, Daegu University, Gyeongsan, Gyeongbuk 38453, Republic of Korea; Sustainable Environmental Process Research Institute, Daegu University, Gyeongsan, Gyeongbuk 38453, Republic of Korea.
Pugazhendhi
P
Arivalagan
Research Institute on Bioengineering, Membrane Technology and Energetics, University of Pannonia, Egyetem ut 10, 8200 Veszprém, Hungary.
Péter
P
Bakonyi
Department of Environmental Engineering, Daegu University, Gyeongsan, Gyeongbuk 38453, Republic of Korea; Sustainable Environmental Process Research Institute, Daegu University, Gyeongsan, Gyeongbuk 38453, Republic of Korea. Electronic address: sanghkim1@daegu.ac.kr.
Sang-Hyoun
SH
Kim
D000085:Acetates / Q000378:metabolism; D000693:Anaerobiosis; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology; D002087:Butyrates / Q000378:metabolism; D003013:Clostridium / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D005285:Fermentation; D005690:Galactose / Q000378:metabolism*; D006358:Hot Temperature; D006859:Hydrogen / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology
D000085:Acetates; D002087:Butyrates; D012722:Sewage; D006859:Hydrogen; D005690:Galactose
Bioaugmentation; Cluster I Clostridium; Galactose; Hydrogen production rate; Hydrogen yield