Potentials of using mixed culture bacteria incorporated with sodium bicarbonate for hydrogen production from water hyacinth

• Published in: Bioresource technology Vol. 263; pp. 365 - 374
• Main Authors: Wazeri, Alaa, Elsamadony, Mohamed, Roux, Sophie Le, Peu, Pascal, Tawfik, Ahmed
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.09.2018; Elsevier
• Subjects: Buffering capacity; Environmental Sciences; Hydrogen production; Lignocellulosic waste; Microbial community; Buffering capacity; Hydrogen production; Microbial community; Lignocellulosic waste; BUFFERING CAPACITY; HYDROGEN PRODUCTION; MICROBIAL COMMUNITY; LIGNOCELLULOSIC WASTE
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2018.05.021

•Low alkalinity of water hyacinth revealed low H2 productivity.•NaHCO3 supplementation enhanced H2 production, content, and hydrogenase enzyme.•Addition of NaHCO3 stimulated higher cellulase and xylanase enzymes activities.•NaHCO3 incremented the abundance of Firmicutes to 71% of the total OTU’s.•Net gain energy was augmented to 0.485 ± 0.029 kJ/gfeedstock by the aid of NaHCO3. The aim of this study is to assess the potentials of using mixed culture bacteria incorporated with different concentrations of NaHCO3 for hydrogen production from water hyacinth (WH). The lowest hydrogen yield (HY) of 30.4 ± 1.9 mL/gTVS, H2 content (HC) of 19.5 ± 1.5% and hydrogenase enzyme (HE) activity of 0.06 ± 0.01 mgM.Breduced/min were registered for the cultures without supplementation of NaHCO3. The HY, HC, and HE activity were maximized at levels of 69.2 ± 4.3 mL/gTVS, 58.4 ± 3.6% and 0.18 ± 0.01 mgM.Breduced/min. respectively for the anaerobes supplied with 3.0 g NaHCO3/L. Furthermore, cellulose, hemicellulose, and lignin destruction efficiencies were 37.2 ± 2.3, 30.0 ± 1.9 and 20.9 ± 1.3% respectively due to the increase of cellulase and xylanase activities up to 2.73 ± 0.17 and 1.87 ± 0.12 U/mL, respectively. Moreover, the abundance of Firmicutes was substantially increased and accounted for 71% of the total OTU’s. Microbes belonging to the order Clostridiales and OPB54 were particularly enriched in the medium supplemented with NaHCO3.