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Hou Z, Pan H, Gu M, Chen X, Ying T, Qiao P, Cao J, Wang H, Hu T, Zheng L, Zhong W. Simultaneously degradation of various phthalate esters by Rhodococcus sp. AH-ZY2: Strain, omics and enzymatic study. JOURNAL OF HAZARDOUS MATERIALS 2024; 474:134776. [PMID: 38852255 DOI: 10.1016/j.jhazmat.2024.134776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 05/14/2024] [Accepted: 05/29/2024] [Indexed: 06/11/2024]
Abstract
Phthalate esters (PAEs) are widely used as plasticizers and cause serious complex pollution problem in environment. Thus, strains with efficient ability to simultaneously degrade various PAEs are required. In this study, a newly isolated strain Rhodococcus sp. AH-ZY2 can degrade 500 mg/L Di-n-octyl phthalate completely within 16 h and other 500 mg/L PAEs almost completely within 48 h at 37 °C, 180 rpm, and 2 % (v/v) inoculum size of cultures with a OD600 of 0.8. OD600 = 0.8, 2 % (v/v). Twenty genes in its genome were annotated as potential esterase and four of them (3963, 4547, 5294 and 5359) were heterogeneously expressed and characterized. Esterase 3963 and 4547 is a type I PAEs esterase that hydrolyzes PAEs to phthalate monoesters. Esterase 5294 is a type II PAEs esterase that hydrolyzes phthalate monoesters to phthalate acid (PA). Esterase 5359 is a type III PAEs esterase that simultaneously degrades various PAEs to PA. Molecular docking results of 5359 suggested that the size and indiscriminate binding feature of spacious substrate binding pocket may contribute to its substrate versatility. AH-ZY2 is a potential strain for efficient remediation of PAEs complex pollution in environment. It is first to report an esterase that can efficiently degrade mixed various PAEs.
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Affiliation(s)
- Zhengyu Hou
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Hejuan Pan
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Mengjie Gu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Xiaowang Chen
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Tongtong Ying
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Pei Qiao
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Junwei Cao
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Haixia Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Tong Hu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Lianbao Zheng
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Weihong Zhong
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, China.
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Wang L, Li Z, Li M, Chen Y, Zhang Y, Bao W, Wang X, Qi Z, Zhang W, Tao Y. Mechanisms of synthetic bacterial flora YJ-1 to enhance cucumber resistance under combined phthalate-disease stresses. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 365:121564. [PMID: 38944953 DOI: 10.1016/j.jenvman.2024.121564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 06/15/2024] [Accepted: 06/18/2024] [Indexed: 07/02/2024]
Abstract
Biotic and abiotic stresses have emerged as major constraints to agricultural production, causing irreversible adverse impacts on agricultural production systems and thus posing a threat to food security. In this study, a new strain of Bacillus subtilis DNYB-S1 was isolated from soil contaminated with Fusarium wilt. It was found that artificially synthetic flora (YJ-1) [Enterobacter sp. DNB-S2 and Rhodococcus pyridinovorans DNHP-S2, DNYB-S1] could effectively mitigate both biotic (Fusarium wilt) and abiotic (phthalates) sources of stresses, with the inhibition rate of YJ-1 resistant to wilt being 71.25% and synergistic degradation of 500 mg/L PAEs was 91.23%. The adaptive difference of YJ-1 was 0.59 and the ecological niche overlap value was -0.05 as determined by Lotka-Volterra modeling. These results indicate that YJ-1 has good ecological stability. The major degradation intermediates included 2-ethylhexyl benzoate (EHBA), phthalic acid (PA), diisobutyl phthalate (DIBP), and butyl benzoate, suggesting that YJ-1 can provide a more efficient pathway for PAEs degradation. In addition, there was metabolic mutualism among the strains that will selectively utilize the provided carbon source (some metabolites of PAEs) for growth. The pot experiment showed that YJ-1 with cucumber reduced the incidence of cucumber wilt by 45.31%. YJ-1 could reduce the concentration of PAEs (DBP: DEHP = 1:1) in soil species from 30 mg/kg to 4.26 mg/kg within 35 d, with a degradation efficiency of 85.81%. Meanwhile, the concentration of PAEs in cucumber was reduced to 0.01 mg/kg, indicating that YJ-1 is directly involved in the degradation of soil PAEs and the enhancement of plant immunity. In conclusion, this study provides a new perspective for the development of customized microbiomes for phytoremediation under combined biotic-abiotic stresses in agricultural production processes.
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Affiliation(s)
- Lei Wang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, PR China
| | - Zhe Li
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, PR China
| | - MingZe Li
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, PR China
| | - YuXin Chen
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, PR China
| | - Ying Zhang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, PR China.
| | - WenJing Bao
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, PR China
| | - XiaoDong Wang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, PR China
| | - ZeWei Qi
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, PR China
| | - WenQian Zhang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, PR China
| | - Yue Tao
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, PR China
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Ningthoujam R, Pinyakong O. Exploring di (2-ethylhexyl) phthalate degradation by a synthetic marine bacterial consortium: Genomic insights, pathway and interaction prediction, and application in sediment microcosms. JOURNAL OF HAZARDOUS MATERIALS 2024; 472:134557. [PMID: 38735188 DOI: 10.1016/j.jhazmat.2024.134557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 05/01/2024] [Accepted: 05/04/2024] [Indexed: 05/14/2024]
Abstract
Di (2-ethylhexyl) phthalate (DEHP), a toxic phthalate ester (PAE) plasticizer, is often detected in marine sediment and biota. Our understanding of DEHP-degrading marine bacteria and the associated genetic mechanisms is limited. This study established a synthetic bacterial consortium (A02) consisting of three marine bacteria (OR05, OR16, and OR21). Consortium A02 outperformed the individual strains in DEHP degradation. Investigations into the degradation of DEHP intermediates revealed that OR05 and OR16 likely contributed to enhanced DEHP degradation by Consortium A02 via the utilization of DEHP intermediates, such as protocatechuic acid and mono (ethylhexyl) phthalate, with OR21 as the key DEHP degrader. A pathway of DEHP degradation by Consortium A02 was predicted based on genome analysis and experimental degradation. Bioaugmentation with Consortium A02 led to 80% DEHP degradation in 26 days in saline sediment (100 mg/kg), surpassing the 53% degradation by indigenous microbes, indicating the potential of A02 for treating DEHP-contaminated sediments. Meanwhile, bioaugmentation notably changed the bacterial community, with the exclusive presence of certain bacterial genera in the A02 bioaugmented microcosms, and was predicted to result in a more dynamic and active sediment bacterial community. This study contributes to the limited literature on DEHP degradation by marine bacteria and their associated genes.
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Affiliation(s)
- Ritu Ningthoujam
- International Program in Hazardous Substance and Environmental Management, Graduate School, Chulalongkorn University, Bangkok, Thailand
| | - Onruthai Pinyakong
- Center of Excellence in Microbial Technology for Marine Pollution Treatment (MiTMaPT), Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand; Research Program on Remediation Technologies for Petroleum Contamination, Center of Excellence on Hazardous Substance Management (HSM), Chulalongkorn University, Bangkok, Thailand.
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Wang L, Feng C, Chen Y, Meng Q, Li J, Liu Y, Zhang W, Li Z, Qu J, Zhang Y. Study on the mechanism and degradation behavior of Encifer adhaerens DNM-S1 capturing dimethyl phthalate. CHEMOSPHERE 2024; 358:141919. [PMID: 38641291 DOI: 10.1016/j.chemosphere.2024.141919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 03/14/2024] [Accepted: 04/04/2024] [Indexed: 04/21/2024]
Abstract
The global concern surrounding pollution caused by phthalates is escalating, with dimethyl phthalate (DMP) emerging as one of the most prevalent contaminants within the phthalates (PAEs) category. Although the biodegradation of DMP is considered both safe and efficient, its underlying degradation mechanism is not yet fully elucidated, and the degradation performance can be somewhat inconsistent. To address this issue, our study isolated a DMP-degrading bacterium (DNM-S1) from a vegetable greenhouse. The resulting data revealed that DNM-S1 exhibited a remarkable degradation performance, successfully degrading 84.98% of a 2000 mg L-1 DMP solution within 72 h. Remarkably, it achieved complete degradation of a 50 mg L-1 DMP solution within just 3 h. DMP degradation by DNM-S1 was also found to be efficient even under low-temperature conditions (10 °C). Our research further indicates that DNM-S1 is capable of capturing DMP through the ester bond in the bacterium's cell wall fatty acids, forming hydrogen bonds through hydrophobic interactions. The DMP was then transported into the DNM-S1 protoplasm using an active transport mechanism. Interestingly, the secondary metabolites of DNM-S1 contained natural carotenoids, which could potentially counteract the damaging effects of PAEs on cell membrane permeability. In summary, these findings highlight the potential of DNM-S1 in addressing PAEs pollution and provide new insights into the metabolic mechanism of PAEs degradation.
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Affiliation(s)
- Lei Wang
- School of Resource and Environment, Northeast Agricultural University, Harbin, Heilongjiang, 150030, PR China.
| | - Chengcheng Feng
- School of Resource and Environment, Northeast Agricultural University, Harbin, Heilongjiang, 150030, PR China; Heilongjiang Province Ecological Environment Monitoring Center, Harbin, Heilongjiang, 150056, PR China.
| | - Yuxin Chen
- School of Resource and Environment, Northeast Agricultural University, Harbin, Heilongjiang, 150030, PR China.
| | - Qingqing Meng
- Heilongjiang Province Ecological Environment Monitoring Center, Harbin, Heilongjiang, 150056, PR China.
| | - Jingwei Li
- Heilongjiang Province Ecological Environment Monitoring Center, Harbin, Heilongjiang, 150056, PR China.
| | - Yi Liu
- School of Resource and Environment, Northeast Agricultural University, Harbin, Heilongjiang, 150030, PR China.
| | - Wenqian Zhang
- School of Resource and Environment, Northeast Agricultural University, Harbin, Heilongjiang, 150030, PR China.
| | - Zhe Li
- School of Resource and Environment, Northeast Agricultural University, Harbin, Heilongjiang, 150030, PR China.
| | - Jianhua Qu
- School of Resource and Environment, Northeast Agricultural University, Harbin, Heilongjiang, 150030, PR China.
| | - Ying Zhang
- School of Resource and Environment, Northeast Agricultural University, Harbin, Heilongjiang, 150030, PR China.
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Guan R, Wang L, Zhao Y, Huang F, Zhang Y, Wang X, Chen Y, Li M, Wang D. The mechanism of DEHP degradation by the combined action of biochar and Arthrobacter sp. JQ-1: Mechanisms insight from bacteria viability, degradation efficiency and changes in extracellular environment. CHEMOSPHERE 2023; 341:140093. [PMID: 37678595 DOI: 10.1016/j.chemosphere.2023.140093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/18/2023] [Accepted: 09/05/2023] [Indexed: 09/09/2023]
Abstract
Di(2-ethylhexyl) phthalate (DEHP) has been widely detected in soil, water, and sediment as a priority control pollutant. Immobilized microorganism technology is gradually mature and applied in production. Biochar prepared from agricultural wastes is an excellent immobilized carrier because of its porous structure and abundant functional groups. Environmental acidification was caused by degrading bacteria Arthrobacter sp. JQ-1 (JQ-1) respiration and acidic metabolites during DEHP degradation, which affected the passage life of microorganisms and the removal efficiency of DEHP. The mechanism of DEHP degradation by the combined action of JQ-1 and corn straw biochar (BC) at 600 °C was investigated, and bacterial viability, microenvironmental changes, and kinetic tests were performed in this research. Compared with biodegradation group alone, the degradation rate of DEHP in 1% biochar unloaded and loaded with JQ-1 increased by 18.3% and 30.9%, and its half-life decreased to 23.90 h and 11.95h, a reduction of 31.37 h. The percentage of detected living JQ-1 increased as biochar content increased when loading capacity was less than 1%. In which, (JQ-1-BC2) group was 4.1% higher than (JQ-1-BC1) group. Biochar has the ability to neutralize acidifying environmental pH due to its alkaline functional groups, including lactone group, -OH, -COO-. 1% biochar loaded with JQ-1 increased the pH of the microenvironment by 0.57 and alkaline phosphatase (AKP) activity by 0.0063 U·mL-1, which promoted the reduction of PA. Study suggested that biochar loaded with JQ-1 could simultaneously adsorb and degrade DEHP during the process of DEHP removal. Biochar could be used as a biological stimulant to increase abundance and metabolism, enhance the utilization of DEHP by JQ-1. Biochar (1% (w/v)) loaded with JQ-1 as DEHP removal material showed good performance. Biochar not only as an immobilized carrier, but also as a biostimulant, providing an effective strategy for the collaborative remediation of PAEs contaminated.
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Affiliation(s)
- Rui Guan
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Lei Wang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Ying Zhao
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Fuxin Huang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Ying Zhang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Xiaodong Wang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Yuxin Chen
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Mingze Li
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Didi Wang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
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Fan S, Guo J, Han S, Du H, Wang Z, Fu Y, Han H, Hou X, Wang W. A Novel and Efficient Phthalate Hydrolase from Acinetobacter sp. LUNF3: Molecular Cloning, Characterization and Catalytic Mechanism. Molecules 2023; 28:6738. [PMID: 37764514 PMCID: PMC10537300 DOI: 10.3390/molecules28186738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 09/14/2023] [Accepted: 09/17/2023] [Indexed: 09/29/2023] Open
Abstract
Phthalic acid esters (PAEs), which are widespread environmental contaminants, can be efficiently biodegraded, mediated by enzymes such as hydrolases. Despite great advances in the characterization of PAE hydrolases, which are the most important enzymes in the process of PAE degradation, their molecular catalytic mechanism has rarely been systematically investigated. Acinetobacter sp. LUNF3, which was isolated from contaminated soil in this study, demonstrated excellent PAE degradation at 30 °C and pH 5.0-11.0. After sequencing and annotating the complete genome, the gene dphAN1, encoding a novel putative PAE hydrolase, was identified with the conserved motifs catalytic triad (Ser201-Asp295-His325) and oxyanion hole (H127GGG130). DphAN1 can hydrolyze DEP (diethyl phthalate), DBP (dibutyl phthalate) and BBP (benzyl butyl phthalate). The high activity of DphAN1 was observed under a wide range of temperature (10-40 °C) and pH (6.0-9.0). Moreover, the metal ions (Fe2+, Mn2+, Cr2+ and Fe3+) and surfactant TritonX-100 significantly activated DphAN1, indicating a high adaptability and tolerance of DphAN1 to these chemicals. Molecular docking revealed the catalytic triad, oxyanion hole and other residues involved in binding DBP. The mutation of these residues reduced the activity of DphAN1, confirming their interaction with DBP. These results shed light on the catalytic mechanism of DphAN1 and may contribute to protein structural modification to improve catalytic efficiency in environment remediation.
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Affiliation(s)
- Shuanghu Fan
- College of Life Science, Langfang Normal University, Langfang 065000, China; (S.F.); (S.H.); (H.D.); (Z.W.); (Y.F.); (H.H.)
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Technical Innovation Center for Utilization of Edible and Medicinal Fungi in Hebei Province, Langfang 065000, China
| | - Jingjing Guo
- School of Chemistry and Materials Science, Langfang Normal University, Langfang 065000, China;
| | - Shaoyan Han
- College of Life Science, Langfang Normal University, Langfang 065000, China; (S.F.); (S.H.); (H.D.); (Z.W.); (Y.F.); (H.H.)
| | - Haina Du
- College of Life Science, Langfang Normal University, Langfang 065000, China; (S.F.); (S.H.); (H.D.); (Z.W.); (Y.F.); (H.H.)
| | - Zimeng Wang
- College of Life Science, Langfang Normal University, Langfang 065000, China; (S.F.); (S.H.); (H.D.); (Z.W.); (Y.F.); (H.H.)
| | - Yajuan Fu
- College of Life Science, Langfang Normal University, Langfang 065000, China; (S.F.); (S.H.); (H.D.); (Z.W.); (Y.F.); (H.H.)
- Technical Innovation Center for Utilization of Edible and Medicinal Fungi in Hebei Province, Langfang 065000, China
| | - Hui Han
- College of Life Science, Langfang Normal University, Langfang 065000, China; (S.F.); (S.H.); (H.D.); (Z.W.); (Y.F.); (H.H.)
- Technical Innovation Center for Utilization of Edible and Medicinal Fungi in Hebei Province, Langfang 065000, China
| | - Xiaoqiang Hou
- College of Life Science, Langfang Normal University, Langfang 065000, China; (S.F.); (S.H.); (H.D.); (Z.W.); (Y.F.); (H.H.)
- Technical Innovation Center for Utilization of Edible and Medicinal Fungi in Hebei Province, Langfang 065000, China
| | - Weixuan Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- National Nanfan Research Institute (Sanya), Chinese Academy of Agricultural Sciences, Sanya 572024, China
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Bhattacharyya M, Dhar R, Basu S, Das A, Reynolds DM, Dutta TK. Molecular evaluation of the metabolism of estrogenic di(2-ethylhexyl) phthalate in Mycolicibacterium sp. Microb Cell Fact 2023; 22:82. [PMID: 37101185 PMCID: PMC10134610 DOI: 10.1186/s12934-023-02096-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 04/12/2023] [Indexed: 04/28/2023] Open
Abstract
BACKGROUND Di(2-ethylhexyl) phthalate (DEHP) is a widely detected plasticizer and a priority pollutant of utmost concern for its adverse impact on humans, wildlife and the environment. To eliminate such toxic burden, biological processes are the most promising ways to combat rampant environmental insults under eco-friendly conditions. The present study investigated the biochemical and molecular assessment of the catabolic potential of Mycolicibacterium sp. strain MBM in the assimilation of estrogenic DEHP. RESULTS A detailed biochemical study revealed an initial hydrolytic pathway of degradation for DEHP followed by the assimilation of hydrolyzed phthalic acid and 2-ethylhexanol to TCA cycle intermediates. Besides the inducible nature of DEHP-catabolic enzymes, strain MBM can efficiently utilize various low- and high-molecular-weight phthalate diesters and can grow under moderately halotolerant conditions. Whole genome sequence analysis exhibited a genome size of 6.2 Mb with a GC content of 66.51% containing 6,878 coding sequences, including multiple genes, annotated as relevant to the catabolism of phthalic acid esters (PAEs). Substantiating the annotated genes through transcriptome assessment followed by RT-qPCR analysis, the possible roles of upregulated genes/gene clusters in the metabolism of DEHP were revealed, reinforcing the biochemical pathway of degradation at the molecular level. CONCLUSIONS A detailed co-relation of biochemical, genomic, transcriptomic and RT-qPCR analyses highlights the PAE-degrading catabolic machineries in strain MBM. Further, due to functional attributes in the salinity range of both freshwater and seawater, strain MBM may find use as a suitable candidate in the bioremediation of PAEs.
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Affiliation(s)
- Mousumi Bhattacharyya
- Department of Microbiology, Bose Institute, EN-80, Sector V, Salt Lake, Kolkata, West Bengal, 700091, India
| | - Rinita Dhar
- Department of Microbiology, Bose Institute, EN-80, Sector V, Salt Lake, Kolkata, West Bengal, 700091, India
| | - Suman Basu
- Department of Microbiology, Bose Institute, EN-80, Sector V, Salt Lake, Kolkata, West Bengal, 700091, India
| | - Avijit Das
- Department of Microbiology, Bose Institute, EN-80, Sector V, Salt Lake, Kolkata, West Bengal, 700091, India
| | - Darren M Reynolds
- Centre for Research in Biosciences, Department of Applied Sciences, University of the West of England, Bristol, BS16 1QY, UK
| | - Tapan K Dutta
- Department of Microbiology, Bose Institute, EN-80, Sector V, Salt Lake, Kolkata, West Bengal, 700091, India.
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Wang L, Jia X, Dou Z, Li X, Bao W, Ma C, Wang H, Wang L, Dong M, Zhang Y. Fluorescent labeling and tracing of immobilized efficient degrading bacterium DNB-S1 and its remediation efficiency of DBP contaminated soil. CHEMOSPHERE 2023; 320:138011. [PMID: 36731677 DOI: 10.1016/j.chemosphere.2023.138011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 01/20/2023] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
Dibutyl phthalate (DBP) is an organic pollutant frequently detected in soil, and is a reproductive poison that harms animals both before and after birth and has mutagenic, teratogenic, and carcinogenic effects. DBP removal from farmland has been the subject of extensive research in recent years. Efficient DBP degrading bacterial strains were screened in the laboratory. GFP (Green fluorescent protein) labeled degradation strain GFP-DNB-S1 was analyzed for its activity and dynamics. Using sodium alginate (SA) and nano-hydroxyapatite (n-HAP) as carrier materials and CaCl2 as a cross-linking agent, the immobilized microbial agent n-HAP/SA + DNB-S1 was prepared by embedding cross-linking immobilization technology to study the remediation effect of DBP contaminated soil. The best formation effect of immobilized materials (n-HAP/SA) was found when the SA to n-HAP ratio was 3:2. When compared to single SA immobilized bacteria, n-HAP/SA immobilized bacteria improved the surface roughness and porosity of the microspheres. After 70 days, LED light revealed that the immobilized bacteria's GFP green fluorescent protein expression was stable. At 70 days, the initial DBP concentration of 500 mg ∙ L-1 degraded at a rate of 69.9%. The degrading bacteria had no effect on DBP degradation before and after being labeled with GFP. The n-HAP/SA immobilized bacteria offered a better living environment for microorganisms due to their rougher surface and a greater number of pores. This protected the microorganisms and increased the efficiency of DBP degradation. When the concentration of DBP in contaminated soil was set to 20 mg ∙ kg-1 and the n-HAP/SA + DNB-S1 immobilized bacterial agent was applied to the soil, the rate of DBP degradation was determined to be 93.34%. The degradation process followed First-order degradation kinetics, which improved the physical and chemical properties of the soil as well as its fertility.
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Affiliation(s)
- Lei Wang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Xiaochen Jia
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Zeyu Dou
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Xiaoqian Li
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Wenjing Bao
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Chaoran Ma
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Hongye Wang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Lei Wang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Maofeng Dong
- Pesticide Safety Evaluation Research Center, Shanghai Academy of Agricultural Sciences, 2901 Beizhai Road, Minhang District, Shanghai, China
| | - Ying Zhang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
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