1
|
Zheng Y, Feng Z, Wang P, Xu S, Gao X, Ren L, Yang T, Zhao X, Wei Y, Li J. Suppressive performance of food waste composting with polylactic acid: Emphasis on microbial core metabolism pathways and mechanism. Bioresour Technol 2023:129339. [PMID: 37343797 DOI: 10.1016/j.biortech.2023.129339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 06/23/2023]
Abstract
The aim of this study was to assess the effect of polylactic acid (PLA) on microbial community composition and core metabolism pathways in food waste (FW) composting. The presence of PLA negatively influenced microbial community richness and decreased respectively the abundance of Bacillus, Halocella and Cellvibrio at mesophilic, thermophilic and mature phases. Analysis of microbial metabolism at the gene level help to understand the mechanism in co-composting with FW and PLA. The expression of core functional genes related to lactide metabolism was stimulated by PLA degradation at thermophilic and mature phases. The sum of absolute abundance of functional genes that involved in first and second carbon oxidation of tricarboxylic acid cycle was decreased due to the existence of PLA. The transformation between 2-Oxoglutarate and Succinyl-CoA were interfered in thermophilic phase, which might result in the lower germination index in PLA group (115%) than that in control (186%).
Collapse
Affiliation(s)
- Yi Zheng
- College of Resources and Environmental Science, Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China; Organic Recycling Institute (Suzhou) of China Agricultural University, Suzhou 215128, China
| | - Ziwei Feng
- College of Resources and Environmental Science, Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Pan Wang
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China
| | - Shaoqi Xu
- College of Resources and Environmental Science, Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Xin Gao
- College of Resources and Environmental Science, Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Lianhai Ren
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China
| | - Tianxue Yang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Xinyu Zhao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yuquan Wei
- College of Resources and Environmental Science, Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China; Organic Recycling Institute (Suzhou) of China Agricultural University, Suzhou 215128, China.
| | - Ji Li
- College of Resources and Environmental Science, Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China; Organic Recycling Institute (Suzhou) of China Agricultural University, Suzhou 215128, China
| |
Collapse
|
2
|
Zheng Y, Wang P, Wei Y, Feng Z, Jia Z, Li J, Ren L. Untargeted metabolomics elucidated biosynthesis of polyhydroxyalkanoate by mixed microbial cultures from waste activated sludge under different pH values. J Environ Manage 2023; 331:117300. [PMID: 36657207 DOI: 10.1016/j.jenvman.2023.117300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 01/03/2023] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
Waste activated sludge has been frequently used as mixed substrate to produce polyhydroxyalkanoate (PHA). However, insufficient research on microbial metabolism has led to difficulties in regulating PHA accumulation in mixed microbial cultures (MMCs). To explore the variation of functional genes during domestication and the effect of different pH conditions on metabolic pathways during PHA accumulation, MMCs were domesticated by adding acetate and propionate with aerobic dynamic feeding strategy for 60 days. As the domestication progressed, the microbial community diversity declined and PHA-producing bacteria, Brevundimonas, Dechloromonas and Hyphomonas, were enriched. Through bacterial function prediction by PICRUSt the gene rpoE involved in starvation resistance of bacteria was enriched after the domestication. The pH value of 8.5 was the best condition for PHA accumulation in MMCs, under which a maximum PHA content reached 23.50% and hydroxybutyric (HB)/hydroxyvaleric (HV) reached 2.22. Untargeted metabolomics analysis exhibited that pH conditions of 7 and 8.5 could promote the up-regulation of significant differential metabolites, while higher alkaline conditions caused the inhibition of metabolic activity. Functional annotation showed that pH condition of 8.5 significantly affected Pyrimidine metabolism, resulting in an increase in PHA production. Regarding the pathways of PHA biosynthesis, acetoacetate was found to be significant in the metabolism of hydroxybutyric, and the alkaline condition could restrain the conversion from hydroxybutyric (HB) to the acetoacetate to protect PHB accumulation in MMCs compared with neutral condition. Taken together, the present results can advance the fundamental understanding of metabolic function in PHA accumulation under different pH conditions.
Collapse
Affiliation(s)
- Yi Zheng
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, School of Ecology and Environment, Beijing Technology and Business University, Beijing, 100048, China; College of Resources and Environmental Science, Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China; Organic Recycling Institute (Suzhou) of China Agricultural University, Suzhou, 215128, China
| | - Pan Wang
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, School of Ecology and Environment, Beijing Technology and Business University, Beijing, 100048, China.
| | - Yuquan Wei
- College of Resources and Environmental Science, Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China; Organic Recycling Institute (Suzhou) of China Agricultural University, Suzhou, 215128, China
| | - Ziwei Feng
- College of Resources and Environmental Science, Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China
| | - Zhijie Jia
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, School of Ecology and Environment, Beijing Technology and Business University, Beijing, 100048, China
| | - Ji Li
- College of Resources and Environmental Science, Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China; Organic Recycling Institute (Suzhou) of China Agricultural University, Suzhou, 215128, China
| | - Lianhai Ren
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, School of Ecology and Environment, Beijing Technology and Business University, Beijing, 100048, China.
| |
Collapse
|