Results

Influence of operational conditions on the performance of biogas bioconversion into ectoines in pilot bubble column bioreactors

The 6th DEEP PURPLE publication was received on 18 April 2022, revised 26 May 2022, accepted 27 May 2022 and is available online since 29 May 2022 in Bioresource Technology (Volume 358, 2022, 127398, ISSN 0960-8524). The author team (see below in cite and share) is from the Institute of Sustainable Processes, University of Valladolid.

Abstract
The application of biogas as a low-priced substrate for the production of ectoines constitutes an opportunity to decrease their production costs and to enhance the viability of anaerobic digestion. The influence of operational conditions on CH4-biogas biodegradation and on ectoines production yields was assessed in continuous pilot bubble column bioreactors. The rise in biomass concentration from 1 to 3 g L−1 resulted in a decrease in the specific ectoine content from 42 ± 8 to 30 ± 4 mgectoine gVSS−1. The concentration of Cu2+ and Mg2+ did not impact process performance, while the use of ammonium as N source resulted in low CH4 biodegradation and ectoine yields (13 ± 7 mgectoine gVSS−1). The increase in CH4 content from 4.5 to 9 %v·v−1 enhanced CH4 removal efficiency. Process operation at NaCl concentrations of 3 %w·w−1 instead of 6 %w·w−1 decreased the ectoine yield to 17 mgectoine gVSS−1. Finally, Methylomicrobium buryatense was identified as the dominant species.

Ectoine-production-from-biogas-graphic

Highlights
• Low biomass concentrations resulted in an increase in the ectoines yields.
• The increase in Cu2+ and Mg2+ concentrations did not enhance ectoines synthesis.
• The use of ammonium instead of nitrate as N source induced biomass decay.
• The increase in CH4 concentration did not enhance ectoines yields.
• Low NaCl concentrations enhanced CH4 biodegradation but reduced ectoines yields.

Share and cite
María del Rosario Rodero, Raquel Herrero-Lobo, Víctor Pérez, Raúl Muñoz,
Influence of operational conditions on the performance of biogas bioconversion into ectoines in pilot bubble column bioreactors, Bioresource Technology, Volume 358, 2022, 127398, ISSN 0960-8524, https://doi.org/10.1016/j.biortech.2022.127398.

Find and download the publication here
(https://www.sciencedirect.com/science/article/pii/S0960852422007271)

KEYWORDS: Biogas; Bubble column bioreactor; Ectoine; Hydroxyectoine; Methanotrophs