Fermentative degradation of nonionic surfactants and polyethylene glycol by enrichment cultures and by pure cultures of homoacetogenic and propionate-forming bacteria

Abstract

Linear alkyl ethoxylates (polyethylene glycol alkyl ethers) were fermented completely to methane and CO2 in enrichment cultures inoculated with anoxic sewage sludge. Long-chain fatty acids were released as intermediates. No degradation was found with polypropylene glycol and polypropylene glycol-containing surfactants. Two types of primary ethoxylate-degrading bacteria were isolated and characterized. Both degraded polyethylene glycols with molecular weights of 1,000 completely. Strain KoB35 fermented polyethylene glycol, ethoxyethanol, and lactate to acetate and propionate and was assigned to the described species Pelobacterpropionicus. Strain KoB58 converted polyethylene glycol and many other substrates to acetate only and was assigned to the genus Acetobacterium. The pathways of anaerobic degradation of nonionic surfactants are discussed with respect to their limitations and the various groups of bacteria involved.

Involvement of a quinoprotein (PQQ-containing) alcohol dehydrogenase in the degradation of polypropylene glycols by the bacterium Stenotrophomonas maltophilia

“…The temperature optimum for PPG-DH activity was found to be 50 ‡C, and the enzyme was stable up to 60 ‡C (both tested in 0.1 M TrisĤ Cl bu¡er, pH 8.0). Addition of NH 4 Cl, ethylamine, EDTA, Ca 2þ or Mg 2þ to the assay mixture did not a¡ect the speci¢c activity value.…”

“…In line with this, it has been found that several bacteria are able to use PPGs as carbon and energy source [2]. Since most PEG-utilizing bacteria do not grow on PPG [3,4], the biological degradation pathways of PEG and PPG could be dissimilar.…”

Degradation of alkylphenol ethoxylates by Pseudomonas sp. strain TR01

“…Only a few APE-degrading microorganisms have been reported so far, in contrast to many that are known to degrade PEG (6,8,13,16,22,29,32,33). Maeda and Mikami isolated several NPE-degrading pseudomonad bacteria from various samples and reported that these strains degraded NPE almost completely, the final TOC removal efficiency reaching approx.…”

“…In this paper we report on the isolation and identification of a pseudomonad bacterium which is capable of utilizing APE as the sole carbon source. This bacterium is shown to possess a unique metabolic system for APE degradation, in contrast to the polyethylene glycol (PEG)-degrading bacteria reported so far (4,6,11,16,32,33) (PEG is a structural molecule of APE).…”

Biodegradability of Nonionic Surfactant Used in the Remediation of Groundwaters Polluted with PCE

“…LCFA would be subjected to interconversion processes (Lalman and Bagley, 2001) and degradation by betaoxidation (Fillmore et al, 2011) that typically ends in acetate. The fermentation of PEG has been shown to occur in anaerobic cultures (Lee et al, 2013;Schink and Stieb, 1983;Wagener and Schink, 1988). A more complete description of the possible pathway of Tween decomposition/degradation can be found in Supplemental Material Appendix C. (The Supplemental Materials are found in the online version of this article.)…”