Employing salt-tolerant bacteria Serratia marcescens subsp. SLS for biodegradation of oily kitchen waste. (July 2023)

• Record Type: Journal Article
• Authors: Zhang, Xia; Zhang, Dan; Chu, Shaohua; Khalid, Muhammad; Wang, Renyuan; Chi, Yaowei; Duan, Xiangyu; Yang, Xijia; Zhou, Pei
• Is Part Of: Chemosphere. Volume 329(2023)
• Publication Date: 2023-07
• Subjects: Oily kitchen waste -- Serratia marcescens subsp. SLS -- Oil-degrading -- High NaCl concentration -- Composting -- Biodegradation; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2023.138655
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: The high oil and salt content of kitchen waste (KW) inhibit bioconversion and humus production. To efficiently degrade oily kitchen waste (OKW), a halotolerant bacterial strain, Serratia marcescens subsp. SLS which could transform various animal fats and vegetable oils, was isolated from KW compost. Its identification, phylogenetic analysis, lipase activity assays, and oil degradation in liquid medium were assessed, and then it was employed to carry out a simulated OKW composting experiment. In liquid medium, the 24 h degradation rate of mixed oils (soybean oil: peanut oil: olive oil: lard = 1:1:1:1, v/v/v/v) was up to 87.37% at 30 °C, pH 7.0, 280 rpm, 2% oil concentration and 3% NaCl concentration. The ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS) method demonstrated that the mechanism of SLS strain metabolizing long-chain triglycerides (TAGs) (C53–C60), especially the biodegradation of TAG (C18:3/C18:3/C18:3) by the strain can reach more than 90%. Degradation of 5, 10, 15% concentrations of total mixed oil were also calculated to be 64.57, 71.25, 67.99% respectively after a simulated composting duration of 15 days. The results suggest that the isolated strain of S. marcescens subsp. SLS is suitable for OKW bioremediation in high NaCl concentration within a reasonably short period of time. The findings introduced a salt-tolerant and oil-degrading bacteria, providing insights into the mechanism of oil biodegradation and offering new avenues of study for OKW compost and oily wastewater treatment. Graphical abstract: Image 1 Highlights: A salt-tolerant oil-degrading bacteria was isolated from kitchen waste compost. Serratia marcescens subsp. SLS showed high ability of oil-degrading in liquid medium. The conditions of degradation of mixed oil by strain SLS were optimized. The strain SLS showed efficient oil-degradation under high NaCl concentration. Maximum 71.25% oil reduction degraded by strain SLS in stimulated composting.