Phase-specific microbial relay strategy enhances lipid degradation and humification in aerobic composting of lipid-rich food waste

YangYang Li; ZhuoRui Zhu; ShuaiShuai Li; Yaofu Tan; Hu Xu; Xin Sheng; BaoChuan Qi; JingSheng Wu; Li Li; ZhiWei Zhao

doi:10.1016/j.jenvman.2025.126342

Phase-specific microbial relay strategy enhances lipid degradation and humification in aerobic composting of lipid-rich food waste

J Environ Manage. 2025 Jun 26:390:126342. doi: 10.1016/j.jenvman.2025.126342. Online ahead of print.

Authors

YangYang Li¹, ZhuoRui Zhu², ShuaiShuai Li³, Yaofu Tan⁴, Hu Xu⁵, Xin Sheng⁶, BaoChuan Qi⁷, JingSheng Wu⁸, Li Li⁹, ZhiWei Zhao¹⁰

Affiliations

¹ College of Environment and Ecology, Chongqing University, Chongqing, China. Electronic address: 20221701022@stu.cqu.edu.cn.
² College of Environment and Ecology, Chongqing University, Chongqing, China. Electronic address: 202217131189@stu.cqu.edu.cn.
³ College of Environment and Ecology, Chongqing University, Chongqing, China. Electronic address: 2998711821@qq.com.
⁴ College of Environment and Ecology, Chongqing University, Chongqing, China. Electronic address: 202217131148@stu.cqu.edu.cn.
⁵ College of Environment and Ecology, Chongqing University, Chongqing, China. Electronic address: xuhu20211117@163.com.
⁶ College of Environment and Ecology, Chongqing University, Chongqing, China. Electronic address: sx791654008@163.com.
⁷ College of Environment and Ecology, Chongqing University, Chongqing, China. Electronic address: qibchuan@163.com.
⁸ Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, China. Electronic address: 2022205081@cqust.edu.cn.
⁹ College of Environment and Ecology, Chongqing University, Chongqing, China; School of Civil and Transportation Engineering, Guangdong University of Technology, Guangdong, China. Electronic address: freelin729@cqu.edu.cn.
¹⁰ School of Civil and Transportation Engineering, Guangdong University of Technology, Guangdong, China. Electronic address: hit_zzw@163.com.

PMID: 40577874
DOI: 10.1016/j.jenvman.2025.126342

Abstract

Lipid-rich food waste poses significant challenges in aerobic composting owing to oil-induced physicochemical barriers (>10 % oil content reduces porosity by 32-45 % and suppresses microbial activity). To bridge this gap, we designed a phase-specific microbial relay strategy integrating Pseudomonas aeruginosa DO1 with thermophilic consortia derived from agricultural soils (CK3). The results demonstrated that DO1 achieved 25 % lipid degradation within 96 h (mesophilic phase, <45 °C) through lipase secretion (121.18-131.45 U/mL) and enzymatic emulsification of lipids, after which its abundance decreased (from 26.99 % to 8.41 %). Subsequently, CK3-derived thermophilic bacteria (Bacillus, 38.54 %; Thermoactinomyces, 2.53 %) and fungi (Wallemia, 21.12 %) dominated the thermophilic phase (>50 °C for >5 d), driving β-oxidation-mediated lipid degradation to 91.91 % and enhancing humification with 92.74 % humic substances. Metagenomic analysis confirmed the enrichment of lipolytic pathways (ko00071, p < 0.01) and the upregulation of ammonia-assimilation genes (glsA/gdhB), reducing nitrogen loss to 25.1 %. This temperature-phased relay strategy enables the efficient in situ degradation of high-lipid waste (>15 % oil), offering a scalable solution for industrial composting.

Keywords: Aerobic composting; Functional genomics; Humification; Lipid degradation; Microbial consortia; Nitrogen conservation.