TY - JOUR
T1 - Effect of inoculum pretreatment on the microbial and metabolic dynamics of food waste dark fermentation
AU - Luo, Lijun
AU - Sriram, Saranya
AU - Davidraj, Johnravindar
AU - Martin, Thomas Louis Philippe
AU - Wong, Jonathan W.C.
AU - Pradhan, Nirakar
N1 - Funding Information:
This work was supported by the Hong Kong Baptist University with grant numbers: RC's start-up grant (Tier 1) and RC-OFSGT2/20-21/SCI/010.
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/8
Y1 - 2022/8
N2 - This study systematically evaluated and compared different inoculum pretreatment methods to quickly select dark fermentative bacteria from anaerobic sludge for the bioconversion of food waste. The hydrogen (H2) production rate was found to be highest for 'heat + CO2′ treated inoculum at 140.75 ± 2.61 mL/L/h compared to control experiments (60.27 ± 2.61 mL/L/h). At the same time, H2 yield was found to be highest for alkali-treated inoculum at 157.25 ± 7.62 mL/g of volatile solids (VS) added compared to control experiments (91.61 ± 1.93 mL/g VS). Analysis of organic acids suggests a Clostridial-type fermentation with acetate (0.52 to 1.60 g/L) and butyrate (1.69 to 2.42 g/L) being the major by-products. The microbial data analysis showed that Firmicutes (63.64–90.39%), Bacteroidota (1.16–21.88%), and Proteobacteria (2.09–9.93%) were dominant at the phylum level, whereas genus-level classification showed Clostridium sensu stricto 1 (6.37–42.63%), Streptococcus (1.87–28.96%), Prevotella (0.57–16.59%), and Enterococcus (0.56–14.51%) dominated under different experimental conditions.
AB - This study systematically evaluated and compared different inoculum pretreatment methods to quickly select dark fermentative bacteria from anaerobic sludge for the bioconversion of food waste. The hydrogen (H2) production rate was found to be highest for 'heat + CO2′ treated inoculum at 140.75 ± 2.61 mL/L/h compared to control experiments (60.27 ± 2.61 mL/L/h). At the same time, H2 yield was found to be highest for alkali-treated inoculum at 157.25 ± 7.62 mL/g of volatile solids (VS) added compared to control experiments (91.61 ± 1.93 mL/g VS). Analysis of organic acids suggests a Clostridial-type fermentation with acetate (0.52 to 1.60 g/L) and butyrate (1.69 to 2.42 g/L) being the major by-products. The microbial data analysis showed that Firmicutes (63.64–90.39%), Bacteroidota (1.16–21.88%), and Proteobacteria (2.09–9.93%) were dominant at the phylum level, whereas genus-level classification showed Clostridium sensu stricto 1 (6.37–42.63%), Streptococcus (1.87–28.96%), Prevotella (0.57–16.59%), and Enterococcus (0.56–14.51%) dominated under different experimental conditions.
KW - Amplicon sequence variants
KW - Dark fermentation
KW - Food waste
KW - Hydrogen
KW - Inoculum pretreatment
KW - Organic acids
UR - http://www.scopus.com/inward/record.url?scp=85131409369&partnerID=8YFLogxK
U2 - 10.1016/j.biortech.2022.127404
DO - 10.1016/j.biortech.2022.127404
M3 - Journal article
C2 - 35654323
AN - SCOPUS:85131409369
SN - 0960-8524
VL - 358
JO - Bioresource Technology
JF - Bioresource Technology
M1 - 127404
ER -
