Evaluating interactive toxic impact of heavy metals and variations of microbial community during fermentative hydrogen production. (26th August 2022)

• Record Type: Journal Article
• Authors: Matyakubov, Behzad; Hwang, Yuhoon; Lee, Tae-Jin
• Is Part Of: International journal of hydrogen energy. Volume 47:Number 73(2022)
• Page Start: 31223
• Page End: 31240
• Publication Date: 2022-08-26
• Subjects: Bio-hydrogen -- Heavy metals -- IC50 -- Richness index -- Diversity index; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2022.07.038
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: This study investigated the stimulating or inhibitory effect of Zn, Cu, Cd, Pb, and their mixtures on fermentative hydrogen production. Heavy metals inhibited the production process at all concentrations except 0.50 ppm of Zn. Consistent with the half of the maximum inhibitory concentration (IC50 ), Cu + Pb caused the greatest inhibition as it is more toxic than other heavy metal mixtures. As the concentration of heavy metal increased, the HBu/HAc ratio (butyrate/acetate) tended to decrease and the amount of hydrogen production decreased. Clostridium sp., Klebsiella sp., Dysgonomas sp., Enterobacter sp., and other hydrogen-producing bacteria were observed by polymerase chain reaction (PCR) – analysis by denaturing gradient gel electrophoresis (DGGE) during the fermentative hydrogen process. A significant relationship was observed between the richness index and the hydrogen production ( p -value = 0.01 < 0.05) from the Pielou index. The Pielou index ( E′ ) and the Shannon-Weaver index ( H' ) had no significant relationship ( p -value = 0.12 > 0.05). Graphical abstract: Image 1 Highlights: This study investigated the stimulative or inhibitive effects of Zn, Cu, Cd, Pb. The heavy metals resulted in inhibitory effects at all concentrations except Zn. Cu + Pb caused the highest inhibition by being more toxic than other mixtures. Heavy metals with low IC50 were more sensitive to hydrogen production. Microbial richness, not diversity, is an important factor for hydrogen production.