Kinetic modeling of hydrogen and L-lactic acid production by Thermotoga neapolitana via capnophilic lactic fermentation of starch. (July 2021)

• Record Type: Journal Article
• Authors: Pradhan, Nirakar; d'Ippolito, Giuliana; Dipasquale, Laura; Esposito, Giovanni; Panico, Antonio; Lens, Piet N.L.; Fontana, Angelo
• Is Part Of: Bioresource technology. Volume 332(2021)
• Publication Date: 2021-07
• Subjects: Hydrogen -- Fermentation -- Agri-food waste -- Lactic acid -- Thermotoga neapolitana; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2021.125127
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Under CO2 sparging, T. neapolitana efficiently transforms starch to H2 and lactate. Over 40% of acetate and exogenous CO2 recycled to produce lactate. T. neapolitana could potentially valorize starch-rich waste without pretreatment. Abstract: This study investigated the feasibility of hydrogen (H2 ) and L-lactic acid production from starch under capnophilic lactic fermentation (CLF) conditions by using Thermotoga neapolitana . Batch experiments were performed in 120 mL serum bottles and a 3 L pH-controlled continuous stirred-tank reactors (CSTR) system with potato and wheat starch as the substrates. A H2 yield of 3.34 (±0.17) and 2.79 (±0.17) mol H2 /mol of glucose eq. was achieved with, respectively, potato and wheat starch. In the presence of CO2, L-lactic acid production by the acetyl-CoA carboxylation was significantly higher for the potato starch (0.88 ± 0.39 mol lactic acid/mol glucose eq.) than wheat starch (0.33 ± 0.11 mol lactic acid/mol glucose eq.). A kinetic model was applied to simulate and predict the T. neapolitana metabolic profile and bioreactor performance under CLF conditions. The CLF-based starch fermentation suggests a new direction to biotransform agri-food waste into biofuels and valuable biochemicals.