Biodegradation of malodorous thiols by a Brevibacillus sp. strain isolated from a Tunisian phosphate factory.

Hydrogen sulfide (H2S) and thiols (RSH) generated by the phosphate industry cause harmful effects on human health and quality of life. The present study aims to investigate and evaluate a bacterial strain CAT37 isolated from gas-washing wastewaters in terms of its properties and ability to degrade malodorous thiols. Gas-washing wastewater samples were submitted to physicochemical analyses and used for the isolation of thiol-degrading bacteria. The results from gas chromatography-mass spectrometry (GC-MS) analysis revealed that the isolated strain CAT37 was able to oxidize ∼99% of each thiol, decanethiol and dodecanethiol used as sole carbon and energy sources after 30 days of incubation at 37°C. The strain CAT37 displayed a biodegradative potential on several thiols known by their toxicity and odors. The results from phylogenetic and phenotypic analysis revealed that the CAT37 isolate belonged to the genus Brevibacillus, showing the highest sequence similarity to Brevibacillus agri. Overall, the results indicated that the strain CAT37 exhibited a number of attractive biodegradation abilities against thiols and could be considered a promising candidate for industrial application in future thiol biodeodorization strategies.