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Du H, Cheng JL, Li ZY, Zhong HN, Wei S, Gu YJ, Yao CC, Zhang M, Cai QY, Zhao HM, Mo CH. Molecular insights into the catabolism of dibutyl phthalate in Pseudomonas aeruginosa PS1 based on biochemical and multi-omics approaches. Sci Total Environ 2024; 926:171852. [PMID: 38518818 DOI: 10.1016/j.scitotenv.2024.171852] [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: 01/12/2024] [Revised: 03/19/2024] [Accepted: 03/19/2024] [Indexed: 03/24/2024]
Abstract
A comprehensive understanding of the molecular mechanisms underlying microbial catabolism of dibutyl phthalate (DBP) is still lacking. Here, we newly isolated a bacterial strain identified as Pseudomonas aeruginosa PS1 with high efficiency of DBP degradation. The degradation ratios of DBP at 100-1000 mg/L by this strain reached 80-99 % within 72 h without a lag phase. A rare DBP-degradation pathway containing two monobutyl phthalate-catabolism steps was proposed based on intermediates identified by HPLC-TOF-MS/MS. In combination with genomic and transcriptomic analyses, we identified 66 key genes involved in DBP biodegradation and revealed the genetic basis for a new complete catabolic pathway from DBP to Succinyl-CoA or Acetyl-CoA in the genus Pseudomonas for the first time. Notably, we found that a series of homologous genes in Pht and Pca clusters were simultaneously activated under DBP exposure and some key intermediate degradation related gene clusters including Pht, Pca, Xyl, Ben, and Cat exhibited a favorable coexisting pattern, which contributed the high-efficient DBP degradation ability and strong adaptability to this strain. Overall, these results broaden the knowledge of the catabolic diversity of DBP in microorganisms and enhance our understanding of the molecular mechanism underlying DBP biodegradation.
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Affiliation(s)
- Huan Du
- Guangzhou Customs Technology Center, No. 66 Huacheng Avenue, Tianhe District, Guangzhou 510623, China; Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China; Center for Statistical Science, Tsinghua University, Beijing 100084, China
| | - Ji-Liang Cheng
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China; Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Zhi-Yong Li
- Guangzhou Customs Technology Center, No. 66 Huacheng Avenue, Tianhe District, Guangzhou 510623, China
| | - Huai-Ning Zhong
- Guangzhou Customs Technology Center, No. 66 Huacheng Avenue, Tianhe District, Guangzhou 510623, China
| | - Shuang Wei
- Guangzhou Customs Technology Center, No. 66 Huacheng Avenue, Tianhe District, Guangzhou 510623, China
| | - Yu-Juan Gu
- Guangzhou Customs Technology Center, No. 66 Huacheng Avenue, Tianhe District, Guangzhou 510623, China
| | - Can-Can Yao
- Guangzhou Customs Technology Center, No. 66 Huacheng Avenue, Tianhe District, Guangzhou 510623, China
| | - Miaoyue Zhang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Quan-Ying Cai
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Hai-Ming Zhao
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China.
| | - Ce-Hui Mo
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
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Wu S, Li D, Li H, Su QZ, Liang J, Zheng J, Zhong HN, Dong B. Characterization and elimination efficiency of volatile organic compounds in mechanically recycled polyethylene terephthalate at various recycling stages. Waste Manag 2024; 182:91-101. [PMID: 38643526 DOI: 10.1016/j.wasman.2024.04.029] [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: 12/07/2023] [Revised: 03/13/2024] [Accepted: 04/16/2024] [Indexed: 04/23/2024]
Abstract
The recycling of polyethylene terephthalate (PET) stands as an effective strategy for mitigating plastic pollution and reducing resource waste. The study aimed to investigate the characterization and elimination efficiency of volatile organic compounds (VOCs) present in rPET at various recycling stages using comprehensive two-dimensional gas chromatography-quadrupole-time-of-flight-mass spectrometry coupled with chemometrics. The results revealed that 52, 135, 95, 44, and 33 VOCs, mostly classified into three chemical groups, were tentatively identified in virgin - PET (v-PET), cold water washed - rPET (C-rPET), decontaminated - rPET (D-rPET), melt-extruded - rPET (M-rPET), and solid-state polycondensation - rPET (S-rPET), respectively. Regarding the VOCs with high and median detection frequencies, fatty acyls showed the highest elimination efficiency (100 % and 92 %), followed by organooxygen compounds (81 % and 99 %), others (97 % and 95 %), and benzene and substituted derivatives (82 % and 95 %) in term of HS-SPME. Following the recycling process, there was a general decrease in the concentration of almost all VOCs, as evidenced by the substantial reduction of o-Xylene, hexanoic acid, octanal, and D-limonene from 18.11, 22.43, 30.74, and 7.41 mg/kg to 0, 0, 3.97, and 0 mg/kg, respectively. However, it was noteworthy that the VOCs identified in the samples were not completely extracted, owing to the limitations of HS-SPME. Furthermore, chemometrics analysis indicated significant discrimination among VOCs from vPET, C-rPET, D-rPET, and M-rPET, while indistinct differences were observed between M-rPET and S-rPET. This study contributes to the enhancement of the recycling process and emphasizes the importance of safeguarding consumer health in terms of elimination of VOCs.
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Affiliation(s)
- Siliang Wu
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Dan Li
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Hanke Li
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Qi-Zhi Su
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Jinxin Liang
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Jianguo Zheng
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Huai-Ning Zhong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China.
| | - Ben Dong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
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Wu X, Su QZ, Yue X, Li H, Yang J, Wu S, Zhong HN, Li D, Jianguo Z, Chen S, Dong B. Occurrence and prioritization of non-volatile substances in recycled PET flakes produced in China. Chemosphere 2024; 352:141508. [PMID: 38387658 DOI: 10.1016/j.chemosphere.2024.141508] [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: 06/23/2023] [Revised: 12/18/2023] [Accepted: 02/19/2024] [Indexed: 02/24/2024]
Abstract
Recycled PET (rPET) is gaining popularity for use in the production of new food contact materials (FCMs) under the context of circular economy. However, the limited information on contaminants in rPET from China and concerns about their potential risk are major obstacles to their use in FCM in China. Fifty-five non-volatile compounds were tentatively identified in 126 batches of hot-washed rPET flakes aimed for food packaging applications in China. Although the 55 substances are not necessarily migratable and may not end up in the contacting media, their presence indicates a need for proper management and control across the value chain. For this reason, the 55 substances prioritized on the basis of level of concerns and in-silico genotoxicity profiler. Among them, dimethoxyethyl phthalate, dibutyl phthalate, bis(2-ethylhexyl) phthalate were classified as level V substances, and Michler's ketone and 4-nitrophenol were both categorized as level V substances and had the genotoxic structure alert, while 2,4,5-trimethylaniline was specified with genotoxic structure alert. The above substances have high priority and may pose a potential risk to human health, therefore special attention should be paid to their migration from rPET. Aside from providing valuable information on non-volatile contaminants present in hot-washed rPET flakes coming from China, this article proposed a prioritization workflow that can be of great help to identify priority substances deserving special attention across the value chain.
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Affiliation(s)
- Xuefeng Wu
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Qi-Zhi Su
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Xin Yue
- Danone open science research center (OSRC), Shanghai, 201204, China
| | - Hanke Li
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Jinghua Yang
- Danone open science research center (OSRC), Shanghai, 201204, China
| | - Siliang Wu
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Huai-Ning Zhong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640, China.
| | - Dan Li
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Zheng Jianguo
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Sheng Chen
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Ben Dong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China.
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Li D, Zeng Y, Ye ZK, Li HK, Li YZ, Dong B, Su QZ, Lin QB, Xiao J, Zhong HN. Analysis of volatile organic compounds and potential odour compounds in food contact paperboard using headspace two-dimensional GC-QTOF-MS. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2023; 40:1482-1493. [PMID: 37831931 DOI: 10.1080/19440049.2023.2259029] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 09/10/2023] [Indexed: 10/15/2023]
Abstract
The objective was to establish a robust and reliable approach for the characterisation of volatile organic compounds (VOCs) present in food contact paperboard. This was achieved through the utilisation of headspace solid-phase microextraction in tandem with comprehensive two-dimensional (2D) gas chromatography (GC) and quadrupole time-of-flight mass spectrometry (HS-SPME-GC × GC-QTOF-MS). The experimental parameters were optimised, involving the use of a DVB/C-WR/PDMS fibre at a temperature of 80 °C for a duration of 30 min. A total of 344 VOCs comprising aldehydes, ketones, alcohols, ethers, esters, alkanes and aromatic compounds, were tentatively identified in the samples. Twelve compounds believed to be from biogenic sources had a high odour impact making them major contributors to potential taint from the paperboard samples. Significant attention should be devoted to five compounds namely, 2-methylnaphthalene, 2-pentyl-furan, furfural, 1-octen-3-one and 1-octen-3-ol due to their potential adverse impact on the organoleptic qualities of packaged food items and their potential toxicity.Abbreviations: C-WR: carbon wide range; DVB: divinylbenzene; GC-MS: gas chromatography - mass spectrometry; GCxGC-QTOF-MS: comprehensive two-dimensional gas chromatography coupled to quadrupole-time-of-flight - mass spectrometry; HS-SPME: headspace - solid phase microextraction; LOD: limit of detection; LOQ: limit of quantification; OAV: odor activity values; PDMS: polydimethylsiloxane; RI: retention index; TTC: threshold of toxicological concern; VOC: volatile organic compound.
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Affiliation(s)
- Dan Li
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, PR China
| | - Ying Zeng
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, PR China
| | - Zhi-Kang Ye
- Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, Jinan University, Zhuhai, PR China
| | - Han-Ke Li
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, PR China
| | - Yu-Zhe Li
- China National Center for Food Safety Risk Assessment, Beijing, PR China
| | - Ben Dong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, PR China
| | - Qi-Zhi Su
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, PR China
| | - Qin-Bao Lin
- Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, Jinan University, Zhuhai, PR China
| | - Jing Xiao
- China National Center for Food Safety Risk Assessment, Beijing, PR China
| | - Huai-Ning Zhong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, PR China
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, PR China
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Hao TY, Lin QB, Wu XF, Wu SL, Zhong HN, Dong B, Chen ZF, Ye ZK, Wang ZW, Xu X. Authentication of recycled and virgin polyethylene terephthalate based on UPLC-Q-TOF-MS using non-volatile organic compounds and chemometrics. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2023; 40:1114-1130. [PMID: 37410927 DOI: 10.1080/19440049.2023.2227732] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/09/2023] [Accepted: 06/09/2023] [Indexed: 07/08/2023]
Abstract
Plastic packaging waste, such as polyethylene terephthalate (PET) has increased significantly in recent decades, arousing a considerable and serious public concern regarding the environment, economy, and policy. Plastic recycling is a useful tool to mitigate this issue. Here, a feasible study was performed to investigate the potential of a novel method for identifying virgin and recycled PET. Ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was combined with various chemometrics, as a simple and reliable method that achieved a high discrimination rate for 105 batches of virgin PET (v-PET) and recycled PET (r-PET) based on 202 non-volatile organic compounds (NVOCs). Making use of orthogonal partial least-squares discrimination analysis (OPLS-DA) together with non-parametric tests, 26 marker compounds (i.e. 12 intentionally added substances (IAS) and 14 non-intentionally added substances (NIAS) as well as 31 marker compounds (i.e. 11 IAS and 20 NIAS) obtained from positive and combination of positive and negative ionization modes of UPLC-Q-TOF-MS, respectively, were successfully identified. Moreover, 100% accuracy was obtained using a decision tree (DT). Cross-discrimination based on misclassified samples using various chemometrics allowed the prediction accuracy to be improved and to identify a large sample set, thus greatly enhancing the application scope of this method. The possible origins of these detected compounds can be the plastic itself, as well as contamination from food, medicine, pesticides, industry-related substances, and degradation and polymerization products. As many of these compounds are toxic, especially those pesticide related, this indicates an urgent requirement for closed loop recycling. Overall, this analytical method provides a quick, accurate, and robust way to distinguish virgin from recycled PET and thus addresses the issue of potential virgin PET adulteration thereby detecting fraud in the area of PET recycling.
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Affiliation(s)
- Tian-Ying Hao
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, College of Packaging Engineering, Jinan University, Zhuhai, China
| | - Qin-Bao Lin
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, College of Packaging Engineering, Jinan University, Zhuhai, China
| | - Xue-Feng Wu
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs District Technology Center, Guangzhou, Guangdong, China
| | - Si-Liang Wu
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs District Technology Center, Guangzhou, Guangdong, China
| | - Huai-Ning Zhong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs District Technology Center, Guangzhou, Guangdong, China
| | - Ben Dong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs District Technology Center, Guangzhou, Guangdong, China
| | - Zhi-Feng Chen
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, College of Packaging Engineering, Jinan University, Zhuhai, China
| | - Zhi-Kang Ye
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, College of Packaging Engineering, Jinan University, Zhuhai, China
| | - Zhi-Wei Wang
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, College of Packaging Engineering, Jinan University, Zhuhai, China
| | - Xiaowen Xu
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, College of Packaging Engineering, Jinan University, Zhuhai, China
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Dong B, Wu X, Wu S, Li H, Su QZ, Li D, Lin Q, Chen S, Zheng J, Zhu L, Zhong HN. Occurrence of volatile contaminants in recycled poly(ethylene terephthalate) by HS-SPME-GC×GC-QTOF-MS combined with chemometrics for authenticity assessment of geographical recycling regions. J Hazard Mater 2023; 445:130407. [PMID: 36444813 DOI: 10.1016/j.jhazmat.2022.130407] [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: 09/09/2022] [Revised: 11/10/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
A comparison was performed on various methods detecting the volatile contaminants (VCs) in recycled poly(ethylene terephthalate) (rPET) flakes, the results demonstrated that head-space solid phase micro-extraction combined with comprehensive two-dimensional gas chromatograph-tandem quadrupole-time-of-flight mass spectrometry (HS-SPME-GC×GC-QTOF-MS) was a sensitive, effective, accurate method, and successfully applied to analyze 57 rPET flakes collected from different recycling plants in China. A total of 212 VCs were tentatively identified, and the possible source were associated with plastic, food, and cosmetics. 45 VCs are classified as high-priority compounds with toxicity level IV or V and may pose a risk to human health. Combined chemometrics for further analysis revealed that significant differences among these three geographical recycling regions. 6, 7, and 6 volatile markers were chosen based on VIP values and S-plot among plant1 plant 2 and plant 3, respectively. The markers differed significantly between recycled rPET samples in three geographical recycling regions based on chemometrics analysis. The initial classification rate and cross-validation accuracy were 100% on the identified VCs. These significant differences demonstrate that a systematic study is needed to obtain a comprehensive data on the contamination of rPET for food contact applications in China.
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Affiliation(s)
- Ben Dong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Xuefeng Wu
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Siliang Wu
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Hanke Li
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Qi-Zhi Su
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Dan Li
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Qinbao Lin
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, Jinan University, Zhuhai 519070, China; Working Group on Sustainable Food Contact Materials, Guangzhou 510070, China
| | - Sheng Chen
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China; Working Group on Sustainable Food Contact Materials, Guangzhou 510070, China
| | - Jianguo Zheng
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China
| | - Lei Zhu
- China National Center for Food Safety Risk Assessment, Beijing 100022, China.
| | - Huai-Ning Zhong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou 510075, China; Working Group on Sustainable Food Contact Materials, Guangzhou 510070, China; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.
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Guan MY, Zhong HN, Wang ZW, Yu WW, Hu CY. Chemical contaminants from food contact materials and articles made from or containing wood and bamboo - a review. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2023; 40:434-453. [PMID: 36693199 DOI: 10.1080/19440049.2023.2167003] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Due to recently introduced 'so-called' bio- and plant-based friendly food contact materials and articles (FCM/FCA), some neglected safety issues need to be raised. In this review, potential chemical contaminants from FCM/FCA made from or containing wood and bamboo are presented. Sources, migration, and analytical issues in determining contaminants including intentionally and non-intentionally added substances (IAS and NIAS, respectively) are reviewed. Most of the contaminants are components from melamine-formaldehyde-resin (MFR), paints and coatings, preservatives, and bleaching agents. Tableware made of MFR containing bamboo fibres as a filler are not always suitable for use as tableware since harmful amounts of melamine and formaldehyde can migrate from the tableware into food and even accelerate the degradation of certain polymers with which they are mixed. In addition, in the EU bamboo in plastic FCM is not authorized under Regulation (EU) 10/2011. Paints and coatings used to provide surface coverage for bamboo and wooden articles also pose a risk of migration of heavy metals. Limits on preservatives in wood FCM are covered by legislation in many countries, nevertheless their contamination should not be ignored. Some wood species are considered 'toxic' or contain 'toxic' constituents that should not be used in contact with food, which are worth considering for legislation. IAS analyses in bamboo and wooden FCM is generally not a problem, but has proven to be more challenging for NIAS. Due to a complex mixture of substances contained in plant-based materials, there is a need to improve databases for non-target screening of such chemicals.
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Affiliation(s)
- Mu-Ying Guan
- Department of Food Science & Engineering, Jinan University, Guangzhou City, China
| | - Huai-Ning Zhong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou City, China
| | - Zhi-Wei Wang
- Packing Engineering Institute, Jinan University, Zhuhai, China
| | - Wen-Wen Yu
- Department of Food Science & Engineering, Jinan University, Guangzhou City, China
| | - Chang-Ying Hu
- Department of Food Science & Engineering, Jinan University, Guangzhou City, China
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Hu JL, Duan Y, Zhong HN, Lin QB, Zhang T, Zhao CC, Chen S, Dong B, Li D, Wang J, Mo MZ, Chen J, Zheng JG. Analysis of microplastics released from plastic take-out food containers based on thermal properties and morphology study. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2023; 40:305-318. [PMID: 36538705 DOI: 10.1080/19440049.2022.2157894] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Plastic take-out food containers may release microplastics (MPs) into food and pose a potential risk to food safety and human health. Here, after being subjected to hot water treatment, MPs released from three types of plastic food containers (polypropylene, PP; polyethylene, PE; expanded polystyrene, EPS) were identified by micro-Raman spectroscopy. The results showed that the size of released MPs ranged from 0.8-38 μm and over 96% MPs were smaller than 10 μm. Various MPs concentrations were found from the three types of containers, that is, 1.90 × 104, 1.01 × 105, and 2.82 × 106 particles/L on average from PP, PE, and EPS, respectively. Moreover, based on thermal and morphology analysis, we discovered that both relaxations of the polymer chains in the rubbery state and defects caused by processing techniques might contribute to the release of MPs. Thus, such release can be reduced by increasing the thermal stability of the materials and mitigating the defects generated during production.
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Affiliation(s)
- Jia-Ling Hu
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, Jinan University, Zhuhai, China
| | - Yipin Duan
- Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Huai-Ning Zhong
- Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Qin-Bao Lin
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, Jinan University, Zhuhai, China
| | - Tianlong Zhang
- Guangzhou Customs Technology Center, Guangzhou, Guangdong, China.,School of Chemical Engineering, The University of Queensland, Brisbane, Qld, Australia
| | - Chuang-Chuang Zhao
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, Jinan University, Zhuhai, China
| | - Sheng Chen
- Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Ben Dong
- Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Dan Li
- Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Jing Wang
- Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Ming-Zhen Mo
- Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Jie Chen
- Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Jian-Guo Zheng
- Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
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Guan MY, Hu CY, Peng QS, Zeng Y, Wen-Wei A, Wu ZC, Wang ZW, Zhong HN. Formation and migration of 5-hydroxymethylfurfural and furfural from food contact bamboo sticks during heating and their safety evaluation. J Food Compost Anal 2023. [DOI: 10.1016/j.jfca.2023.105146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Zhang YC, Lin QB, Zhong HN, Zeng Y. Identification and source analysis of volatile flavor compounds in paper packaged yogurt by headspace solid-phase microextraction-gas chromatography-mass spectrometry. Food Packag Shelf Life 2022. [DOI: 10.1016/j.fpsl.2022.100947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Hao TY, Xu X, Lin QB, Wu SL, Wu XF, Hu JL, Zhong HN, Dong B, Chen ZF, Ye ZK, Wang ZW. Rapid discrimination of recycled and virgin poly(ethylene terephthalate) based on non-targeted screening of semi-volatile organic compounds using a novel method of DSI/GC×GC-Q-TOF-MS coupled with various chemometrics. Food Packag Shelf Life 2022. [DOI: 10.1016/j.fpsl.2022.100978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Chen ZF, Lin QB, Dong B, Zhong HN, Wang ZW. Comparison of the ability of UV-Vis and UPLC-Q-TOF-MS combined with chemometrics to discriminate recycled and virgin polyethylene. J Hazard Mater 2022; 423:127165. [PMID: 34844336 DOI: 10.1016/j.jhazmat.2021.127165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 07/05/2021] [Revised: 08/21/2021] [Accepted: 09/05/2021] [Indexed: 06/13/2023]
Abstract
A growing attention is attracted to the use of recycled plastics as food contact materials, and its chemical safety research and discrimination approach are indispensable. In current study, ultraviolet-visible spectrometry (UV-Vis) and ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) were used to provide spectral and mass fingerprinting for polyethylene (PE). Coupling with chemometrics, two methods were developed to discriminate recycled and virgin PE. UV-Vis combined with chemometrics could be a more accessible, simpler and faster approach. 237-331 nm in UV spectrum was regarded as marker region selected by orthogonal partial least-squares discrimination analysis (OPLS-DA) and the accuracy of both calibration and validation set could reach 100% in linear discrimination analysis (LDA) based on this region. Besides, 2314 ions were detected by UPLC-Q-TOF-MS and processed by MS-DIAL. 48 candidate chemicals were identified, including ketone, esters, carboxylic acid, alcohols and phenols, amine, nitriles, aldehydes and others. Possible origins of these compounds could be classified as plastic, food, drug, cosmetics and pesticide related. Many of these compounds are highly toxic, especially pesticide related, indicating that recycling in closed loop or sorting by the recycled plastic articles is very necessary if the recycled PE is going to be used as food contact material.
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Affiliation(s)
- Zhi-Feng Chen
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, Jinan University, Zhuhai 519070, China
| | - Qin-Bao Lin
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, Jinan University, Zhuhai 519070, China.
| | - Ben Dong
- Guangdong Provincial Key Laboratory of Import and Export Technical Measures of Animal, Plant and Food, Guangzhou Customs Technology Center, Guangzhou, Guangdong 510623, China
| | - Huai-Ning Zhong
- Guangdong Provincial Key Laboratory of Import and Export Technical Measures of Animal, Plant and Food, Guangzhou Customs Technology Center, Guangzhou, Guangdong 510623, China; China Certification and Inspection Group Guangdong Co. Ltd, Guangzhou 510623, China
| | - Zhi-Wei Wang
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, Jinan University, Zhuhai 519070, China
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Zhong HN, Zeng Y, Yang DY, Wu ZC, Li D, Sui HX, Gao J, Chen YF, Mo CH. Investigation of factors influencing the release of chloropropanols (3-MCPD and 1,3-DCP) from food contact paper. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2021; 38:2036-2044. [PMID: 34477493 DOI: 10.1080/19440049.2021.1970241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Chloropropanols such as 3-monochloropropane-1,2-diol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) have drawn increasing attention due to their release from food contact paper and their potential carcinogenic effects. In this study, the effects were investigated of water extraction conditions on release of chloropropanols from food contact paper, and the extraction efficiencies of chloropropanols by water extract and migration method were compared. Cold water was found to be more severe than hot water for extraction of chloropropanols, with the highest water extraction value obtained at 23°C. Two hours of extraction was sufficient as the chloropropanols can be fully extracted from food contact paper within a short period of time. Increase of temperature in the range of 10°C-60°C had little impact on release of chloropropanols, however, the extraction of chloropropanols decreased when high temperatures (80°C or above) were applied due to volatilisation losses. Hence, attention should be paid when choosing extract conditions representing the worst-case scenario. The water extraction value using EN 645 method gives higher results compared to migration test described in GB 31604.1 and GB 5009.156, suggesting that the water extract method was probably more severe. For migration test, aqueous-based simulants were found to be more conservative than oil-based simulants, suggesting the conventional experiment conditions applicable for compliance test of chloropropanols migration can be simplified and optimised.
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Affiliation(s)
- Huai-Ning Zhong
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, Guangdong, China.,School of Environment, Jinan University, Guangzhou, China
| | - Ying Zeng
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Dao-Yuan Yang
- Division III of Risk Assessment, China National Center for Food Safety Risk Assessment, Beijing, China
| | - Ze-Chun Wu
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Dan Li
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Hai-Xia Sui
- Division III of Risk Assessment, China National Center for Food Safety Risk Assessment, Beijing, China
| | - Jie Gao
- Division III of Risk Assessment, China National Center for Food Safety Risk Assessment, Beijing, China
| | - Yan-Fen Chen
- National Reference Laboratory for Food Contact Material (Guangdong), Guangzhou Customs Technology Center, Guangzhou, Guangdong, China
| | - Ce-Hui Mo
- School of Environment, Jinan University, Guangzhou, China
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Chen ZF, Lin QB, Song XC, Chen S, Zhong HN, Nerin C. Discrimination of Virgin and Recycled Polyethylene Based on Volatile Organic Compounds Using a Headspace GC-MS Coupled with Chemometrics Approach. Food Packag Shelf Life 2020. [DOI: 10.1016/j.fpsl.2020.100553] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Zhu LX, Lin QB, Li JY, Zhu HM, Ma HS, Zhong HN, Pan JJ. Sources of potassium permanganate consumption for food contact paper. Food Packag Shelf Life 2019. [DOI: 10.1016/j.fpsl.2019.100319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Song XC, Wrona M, Nerin C, Lin QB, Zhong HN. Volatile non-intentionally added substances (NIAS) identified in recycled expanded polystyrene containers and their migration into food simulants. Food Packag Shelf Life 2019. [DOI: 10.1016/j.fpsl.2019.100318] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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17
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Su QZ, Vera P, Van de Wiele C, Nerín C, Lin QB, Zhong HN. Non-target screening of (semi-)volatiles in food-grade polymers by comparison of atmospheric pressure gas chromatography quadrupole time-of-flight and electron ionization mass spectrometry. Talanta 2019; 202:285-296. [PMID: 31171184 DOI: 10.1016/j.talanta.2019.05.029] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/30/2019] [Accepted: 05/03/2019] [Indexed: 01/16/2023]
Abstract
Atmospheric pressure gas chromatography (APGC) coupled to quadrupole time-of-flight (QTOF) and electron ionization mass spectrometry together with commercial library search are two complementary techniques for non-target screening of volatile and semi-volatile compounds. Optimization was first conducted to achieve easier search of correspondent peaks between the two systems. Analytical strategy for the determination of volatile and semi-volatile compound with different identification confidence levels was then proposed and applied to food contact grade polypropylene (PP) samples. Identification was found to be much easier and less time-consuming especially when correspondent peak was found in the two systems with the help of library search, exact mass of precursor and fragment ions as well as Kovats Index (KI). The behavior of APGC-QTOF-MS was also further investigated. Apart from the M+. ion and the well-known adduct [M+H]+ others such as [M-3H + O]+, [M-3H+2O]+ and [M-H+3O]+ were also observed for n-alkanes. Besides, new reaction products were found, formed by diol compounds (1-Monostearoylglycerol, 2-Monostearoylglycerol and NX 8000K) and silanediol dimethyl, which would be a transformation product of the silicone base septum or the methyl 5% phenyl polysiloxane based column. These new compounds were only detected in APGC-MS-QTOF as EI-GC-MS was not enough sensitive for this purpose.
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Affiliation(s)
- Qi-Zhi Su
- Department of Analytical Chemistry, GUIA Group, I3A, EINA, University of Zaragoza, María de Luna 3, 50018, Zaragoza, Spain
| | - Paula Vera
- Department of Analytical Chemistry, GUIA Group, I3A, EINA, University of Zaragoza, María de Luna 3, 50018, Zaragoza, Spain
| | - Cathy Van de Wiele
- Department of Analytical Chemistry, GUIA Group, I3A, EINA, University of Zaragoza, María de Luna 3, 50018, Zaragoza, Spain; Antwerp University, Campus Drie Eiken, Building S, Office 7.25, Universiteitsplein 1, B-2610, Antwerp, Belgium
| | - Cristina Nerín
- Department of Analytical Chemistry, GUIA Group, I3A, EINA, University of Zaragoza, María de Luna 3, 50018, Zaragoza, Spain.
| | - Qin-Bao Lin
- Key Laboratory of Product Packaging and Logistics, Packaging Engineering Institute, Jinan University, Zhuhai, 519070, China
| | - Huai-Ning Zhong
- Inspection and Quarantine Technology Center, Guangdong Entry-Exit Inspection and Quarantine Bureau, Guangzhou, Guangdong 510623, China
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Abstract
Three nanocopper/low-density polyethylene (LDPE) composite films were tested in food simulants (3% acetic acid and 10% ethanol) and real food matrices (rice vinegar, bottled water and Chinese liquor) to explore the behaviours of copper migration using ICP-OES and GFAAS. The effects of exposure time, temperature, nanocopper concentration and contact media on the release of copper from nanocopper/LDPE composite films were studied. It was shown that the migration of copper into 10% ethanol was much less than that into 3% acetic acid at the same conditions. With the increase of nanocopper concentration, exposure time and temperature, the release of copper increased. Copper migration does not appear to be significant in the case of bottled water and Chinese liquor compared with rice vinegar with a maximum value of 0.54 μg mL-1 for the CF-0.25# bags at 70°C for 2 h. The presence and morphology of copper nanoparticles in the films and the topographical changes of the films were confirmed by field emission scanning electron microscope (FE-SEM) and atomic force microscope (AFM). In this manner, copper nanoparticles of different morphologies, sizes and distribution were found, and samples with higher nanocopper concentration had a more irregular topography. In the case of Fourier transform infrared spectroscopy (FTIR), no chemical bonds formed between copper nanoparticles and LDPE. Copper nanoparticles were just as physically dispersed in LDPE.
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Affiliation(s)
- Fang Liu
- a Department of Food Science and Engineering , Jinan University , Guangzhou , China
| | - Chang-Ying Hu
- a Department of Food Science and Engineering , Jinan University , Guangzhou , China.,b Key Laboratory of Product Packaging and Logistics of Guangdong Higher Education Institutes , Jinan University , Zhuhai , China
| | - Quan Zhao
- c Guangdong Inspection and Quarantine Technology Center , Guangzhou , China
| | - Yu-Jie Shi
- a Department of Food Science and Engineering , Jinan University , Guangzhou , China
| | - Huai-Ning Zhong
- c Guangdong Inspection and Quarantine Technology Center , Guangzhou , China
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19
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Lin QB, Li H, Zhong HN, Zhao Q, Xiao DH, Wang ZW. Determination of Titanium in Nano-Titanium(IV) Oxide Composite Food Packaging by Microwave Digestion and Inductively Coupled Plasma Atomic Emission Spectrometry and Inductively Coupled Plasma Mass Spectrometry. ANAL LETT 2014. [DOI: 10.1080/00032719.2014.895907] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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20
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Lin QB, Li H, Zhong HN, Zhao Q, Xiao DH, Wang ZW. Migration of Ti from nano-TiO2-polyethylene composite packaging into food simulants. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2014; 31:1284-90. [DOI: 10.1080/19440049.2014.907505] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Yang HP, Zhong HN, Zhou HM. Catalysis of the refolding of urea denatured creatine kinase by peptidyl-prolyl cis-trans isomerase. Biochim Biophys Acta 1997; 1338:147-50. [PMID: 9128132 DOI: 10.1016/s0167-4838(97)00026-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effect of peptidyl-prolyl cis-trans isomerase (PPIase) on the refolding and reactivation courses of urea-denatured creatine kinase was followed by fluorescence emission, ultraviolet difference spectra and recovery of activity. PPIase is shown to accelerate the slow-phasic reaction of the refolding of urea-denatured creatine kinase. The results suggest that the prolyl peptide bond isomerization may be one of the rate-determining steps in the refolding of creatine kinase.
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Affiliation(s)
- H P Yang
- Department of Biological Science and Biotechnology, Tsinghua University, Beijing, China
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22
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Abstract
The conformational changes of creatine kinase during alkaline unfolding and salt-induced folding at high pH have been followed by fluorescence emission and circular dichroism spectra. The results obtained show that at low ionic strength, with increasing pH value, creatine kinase denatured gradually to reach the ultimate unfolded conformation in the vicinity of pH 12.7. With the increase of pH from 9.0 to 12.7, the fluorescence emission maximum red shifted from 337 to 355 nm, indicating complete exposure of the buried tryptophan residues to the solvent. The far-UV CD spectra show that even at pH 12.7, the apparently fully denatured enzyme retains a great part of ordered secondary structure. At pH 12.7 by adding the salt, the relatively unfolded state of denatured enzyme changes into a compact conformational state by hydrophobic collapsing. Folded state induced by salt bound ANS strongly, indicating the existence of increased hydrophobic surface. The above results suggest that the salt-induced folded state at high pH may be the folded intermediate which exists in the general protein folding, and the larger residual ordered secondary structure might become folded being point on the salt-induced folding.
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Affiliation(s)
- H P Yang
- Department of Biological Science and Biotechnology, Tsinghua University, Beijing, P. R. China
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23
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Le WP, Yan SX, Li S, Zhong HN, Zhou HM. Alkaline unfolding and salt-induced folding of yeast alcohol dehydrogenase under high pH conditions. Int J Pept Protein Res 1996; 47:484-90. [PMID: 8836776 DOI: 10.1111/j.1399-3011.1996.tb01099.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The conformational changes of yeast alcohol dehydrogenase during unfolding at alkaline pH have been followed by fluorescence emission and circular dichroism spectra. A result of comparison of inactivation and conformational changes shows that much lower values of alkaline pH are required to bring about inactivation than significant conformational change of the enzyme molecule. At pH 9.5, although the enzyme has been completely inactivated, no marked conformational changes can be observed. Even at pH 12, the apparently fully unfolded enzyme retains some ordered secondary structure. After removal of Zn2+ from the enzyme molecule, the conformational stability decreased. At pH 12 by adding the salt, the relatively unfolded state of denatured enzyme changes into a compact conformational state by hydrophobic collapsing. Folded states induced by salt bound ANS strongly, indicating the existence of increased hydrophobic surface. More extensive studies showed that although apo-YADH and holo-YADH exhibited similar behavior, the folding cooperative ability of apo-enzyme was lower than that of holo-enzyme. The above results suggest that the zinc ion plays an important role in helping the folding of YADH and in stabilizing its native conformation.
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Affiliation(s)
- W P Le
- Department of Biology, Xiamen University, China
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