Fermentative biohydrogen production from tequila vinasse via the lactate-acetate pathway: Operational performance, kinetic analysis and microbial ecology

• Published in: Fuel (Guildford) Vol. 234; pp. 151 - 160
• Main Authors: García-Depraect, Octavio, León-Becerril, Elizabeth
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15.12.2018; Elsevier BV
• Subjects: Acetic acid; Biohydrogen; Clostridium; Correlation analysis; Dark fermentation; Ecological monitoring; Ecology; Energy; Fermentation; Gompertz model; Hydrogen-producing bacteria; Kinetics; Lactic acid; Lactic acid bacteria; Microorganisms; Mixed culture; Next-generation sequencing; Polylactic acid; Substrates; Tequila; Vinasse; Clostridium; Gompertz model; Hydrogen-producing bacteria; Lactic acid bacteria; Dark fermentation; Mixed culture
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2018.06.126

[Display omitted] •The fermentative bioH2 production from tequila vinasse was investigated.•The peak bioH2 production yield and rate were 124 NmL/g VSadded and 159 NmL/L-h.•BioH2 and butyrate were produced as lactate and acetate were consumed.•Clostridium, Streptococcus and Acetobacter were linked to high bioH2 production.•The bioH2 energy yield of 1.5 kJ/g VSadded was obtained. In this study, a comprehensive approach considering the operational performance, kinetic analysis and microbial ecology was employed to investigate the fermentative biohydrogen (bioH2) production from tequila vinasse. Batch fermentations were conducted in a 3-L stirred tank reactor at 35 °C and pH 6.5–5.8. The bioH2 yield of 124 ± 9 NmL/g VSadded and a peak bioH2 production rate of 159 ± 33 NmL/L-h were obtained. Thus, the energy yield and energy production rate were estimated as 1.5 kJ/g VSadded and 48.7 ± 10.2 kJ/L-d, respectively. The metabolic profile and correlation analysis reflected that bioH2 was associated with the consumption of lactate and acetate. The lactate-acetate pathway was consistent with the modeling of substrate consumption, product formation and biomass growth accurately described by the modified Gompertz model. Illumina MiSeq high-throughput sequencing revealed that Clostridium beijerinckii, Streptococcus sp. and Acetobacter lovaniensis were the main species at the highest bioH2 production activity. The results obtained suggested that the lactate-acetate pathway can potentially be used to produce bioH2 from tequila vinasse.