Enhancement of methane production from 1‐hexadecene by additional electron donors. Issue 4 (7th December 2017)

• Record Type: Journal Article
• Authors: Paulo, A. M. S.; Salvador, A. F.; Alves, J. I.; Castro, R.; Langenhoff, A. A. M.; Stams, A. J. M.; Cavaleiro, A. J.
• Is Part Of: Microbial biotechnology. Volume 11:Issue 4(2018:Jul.)
• Page Start: 657
• Page End: 666
• Publication Date: 2017-12-07
• Subjects: Microbial biotechnology -- Periodicals; Biotechnology; Microbiology; 660.62
• DOI: 10.1111/1751-7915.12886
• Languages: English
• ISSNs: 1751-7915

Abstract

Summary: 1‐Hexadecene‐contaminated wastewater is produced in oil refineries and can be treated in methanogenic bioreactors, although generally at low conversion rates. In this study, a microbial culture able to degrade 1‐hexadecene was enriched, and different stimulation strategies were tested for enhancing 1‐hexadecene conversion to methane. Seven and three times faster methane production was obtained in cultures stimulated with yeast extract or lactate, respectively, while cultures amended with crotonate lost the ability to degrade 1‐hexadecene. Methane production from 1‐hexadecene was not enhanced by the addition of extra hydrogenotrophic methanogens. Bacteria closely related to Syntrophus and Smithella were detected in 1‐hexadecene‐degrading cultures, but not in the ones amended with crotonate, which suggests the involvement of these bacteria in 1‐hexadecene degradation. Genes coding for alkylsuccinate synthase alpha‐subunit were detected in cultures degrading 1‐hexadecene, indicating that hydrocarbon activation may occur by fumarate addition. These findings are novel and show that methane production from 1‐hexadecene is improved by the addition of yeast extract or lactate. These extra electron donors may be considered as a potential bioremediation strategy of oil‐contaminated sites with bioenergy generation through methane production. Abstract : In this work, different stimulation strategies were tested for accelerating 1‐hexadecene conversion to methane, namely addition of hydrogenotrophic methanogens or extra electron donors. Our results show that methane production was 7 and 3 times faster in yeast extract‐ and lactate‐stimulated cultures, respectively, compared to non‐stimulated cultures. The involvement of Syntrophus/Smithella ‐related species in 1‐hexadecene methanogenic degradation is shown for the first time.