Effect of external acetate on lactate-based carboxylate platform: Shifted lactate overloading limit and hydrogen co-production

• DOI: 10.1016/j.scitotenv.2021.149885
• Publication Date: 2021-08-26T02:40:13Z
• Authors: Filip Brodowski; Mateusz Łężyk; Natalia Gutowska; Piotr Oleskowicz-...
• Keywords: Electron acceptor; Electron donor; Carboxylate; Elongation

Chain elongation is an anaerobic biotechnological process that converts short chain carboxylates and electron donor (e.g. ethanol, lactate) into more valuable medium carboxylates. Caproate production in lactate-based gaining popularity, however, the relation between lactate (electron donor) acetate acceptor) has not yet been fully elucidated. Herein, for first time, effect of external on a continuously-fed bioreactor was tested to verify how would affect product spectrum, gas production, as well stability efficiency production. Periodic fluctuations caproate were observed continuously fed with sole carbon source due lack acceptor (acetate) low performance. The recovery stable (68.9 ± 2.2 mmol C/L/d), total consumption, high hydrogen co-production (748 76 mLH2/d) addition acetate. conversion second ensured dominant from beginning process. Moreover, despite continuous overloading acetate, achieved (71.7 2.4 C/L/d) previously unobserved occurred (213 30 mLH2/d). Thus, (i.e. acetate) proposed effective method Microbiological analysis showed dominance microbes closely related Ruminococcaceae bacterium CPB6 Acinetobacter throughout Co-occurrence networks based taxon abundances parameters revealed microbial sub-networks responding concentrations.