INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2017
·
IF 3.671
Jiahong Lin,Qiujie Lai,Yingju Liu,Shi Chen,Xueyi Le,Xiaohua Zhou
Magnetically retrievable formulations of laccase potentially promising for biomedical and environmental applications were constructed by immobilization of the enzyme on the surface of magnetic nanoparticles functionalized by siloxane layers with active amino and methacrylyol moieties. The functional magnetic particles were prepared using a hydrolytic polycondensation reaction of tetraethoxysilane with 3-methacryloxypropyltrimethoxysilane (MPS). The results indicated that the amounts of laccase loading on the methacrylyol functional magnetic particles were approximately 150 mg/g under the optimum conditions. The stability of the immobilized laccase was highly enhanced against thermal treatments and provided better long-term storage. Compared to free laccase, the immobilized laccase exhibited significantly higher decolourisation efficiency in the decolorization of a representative dye, methyl red, which resulted from the magnetic particles adsorption and enzymatic catalysis. These results show its great potential for industrial applications.
研究领域:
生物技术
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环境科学
·
医学工程
✓ 已验证
DOI
高影响因子
Environmental Technology & Innovation
·
2020
·
IF 3.356
Xiaochu Chen,Qizhen Zhou,Fengmao Liu,Qingrong Peng,Yanli Bian
The control and removal of pesticide residues from possible pollution source by using improved methods without secondary pollution is essential for reducing its potential hazards to humans. In this work, a method of combining adsorption and degradation for the removal of pesticide residue was investigated based on the biodegradable microporous starch immobilized laccase (LA–MPS). Biosorbent of microporous starch (MPS) were prepared from maize starch by treating with glucoamylase and α -amylase to increase the specific surface area. Then, laccase with natural biological activity was immobilized on the surface of MPS, the prepared LA-MSP was characterized by SEM, FT-IR, activity assay and stability test. Moreover, LA–MPS coupled with mediators were applied to remove two typical triazine herbicides, atrazine and prometryn, in paddy field water sample. The physical action force between the LA–MPS and pesticide molecules resulted in the good adsorption of LA–MPS to the two pesticides. The apparent rate constants of laccase interaction with pesticide molecules were greatly improved by the adsorption process. Compared with natural degradation, the removal efficiency of atrazine and prometryn were increased by 61% in 7 days, which contributed by 43 ∼ 52% of degradation and 10 ∼ 38% of adsorption. These results indicated that the application of LA–MPS prepared by MPS sorbent was a feasible and green approach for the removal of pesticide residues in paddy field water sample.
研究领域:
环境科学
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生物技术
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产品关联
DOI
高影响因子
Bioresources and Bioprocessing
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2018
·Vol. 5
·期 1
·1-8
·
IF 0
Gao Zhen,Yi Yunfei,Zhao Jia,Xia Yongyang,Jiang Min,Cao Fei,Zhou Hua,Wei Ping,Jia Honghua,Yong Xiaoyu
Background Laccase, a multicopper oxidase that catalyzes the oxidation of phenols, aromatic amines, and benzenethiols, has attracted much attention in applications of organic synthesis, bioremediation, and pulp/textile bleaching. However, free laccases cannot be recycled and are easily inactivated in diverse environmental conditions. Enzyme immobilization is a promising strategy to improve stability, resistance to extreme conditions, and reusability of laccase. Results In this study, amino-functionalized magnetic Fe 3 O 4 nanoparticles were synthesized for co-immobilization of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and laccase by glutaraldehyde cross-linking method. The magnetic nanoparticles were characterized with FTIR, XRD and VSM. Cyclic voltammetry was carried out to verify electrochemical behaviors of the co-immobilized laccase and TEMPO nanoparticles. When the co-immobilized laccase and TEMPO nanoparticles were used to decolorize acid fuchsin, the maximum decolorization rate of 77.41% was obtained with the ratio of TEMPO to laccase being 0.3 mM/g:120 U/g. Conclusion The co-immobilized nanoparticles retained above 50% residual activity after eight cycles of operation, which presented an approach to develop a co-immobilized laccase and mediator system for potential industrial application.
研究领域:
生物化学
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环境科学
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DOI
Catalysts
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2024
·Vol. 14
·期 5
·304
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IF 3.8
Hong Zhang,Xin Zhang,Lei Wang,Bo Wang,Xu Zeng,Bo Ren
The immobilization of enzymes is an important strategy to improve their stability and reusability. Enzyme immobilization technology has broad application prospects in biotechnology, biochemistry, environmental remediation, and other fields. In this study, composites of chitosan (CS) and sodium alginate (SA) with Cu2+forming a double-network crosslinked structure of hydrogels were prepared and used for the immobilization of laccase. Fourier infrared spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy tests revealed that laccase molecules were immobilized on the composite hydrogel surface by a covalent bonding method. Compared to free laccase, the pH, temperature, and storage stability of the immobilized laccase were markedly improved. In addition, the immobilized laccase could be easily separated from the reaction system and reused, and it maintained 81.6% of its initial viability after six cycles of use. Bisphenol A (BPA) in polluted water was efficiently degraded using immobilized laccase, and the factors affecting the degradation efficiency were analyzed. Under the optimal conditions, the BPA removal was greater than 82%, and the addition of a small amount of ABTS had a significant effect on BPA degradation, with a removal rate of up to 99.1%. Experimental results indicated that immobilized laccases had enormous potential in actual industrial applications.
研究领域:
生物技术
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环境科学
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酶工程
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产品关联
DOI
高影响因子
MOLECULES
·
2017
·Vol. 22
·期 2
·221
·
IF 2.861
Jing Chen,Juan Leng,Xiai Yang,Liping Liao,Liangliang Liu,Aiping Xiao
In this study, magnetic graphene oxide (MGO) nanomaterials were synthesized based on covalent binding of amino Fe3O4nanoparticles onto the graphene oxide (GO), and the prepared MGO was successfully applied as support for the immobilization of laccase. The MGO-laccase was characterized by transmission electron microscopy (TEM) and a vibrating sample magnetometer (VSM). Compared with free laccase, the MGO-laccase exhibited better pH and thermal stabilities. The optimum pH and temperature were confirmed as pH 3.0 and 35 °C. Moreover, the MGO-laccase exhibited sufficient magnetic response and satisfied reusability after being retained by magnetic separation. The MGO-laccase maintained 59.8% activity after ten uses. MGO-laccase were finally utilized in the decolorization of dye solutions and the decolorization rate of crystal violet (CV), malachite green (MG), and brilliant green (BG) reached 94.7% of CV, 95.6% of MG, and 91.4% of BG respectively. The experimental results indicated the MGO-laccase nanomaterials had a good catalysis ability to decolorize dyes in aqueous solution. Compared with the free enzyme, the employment of MGO as enzyme immobilization support could efficiently enhance the availability and facilitate the application of laccase.Keywords:dyes;graphene oxide;laccase;magnetic nanoparticles
研究领域:
环境科学
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生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
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2022
·
IF 7.968
Abdul Latif,Ahsan Maqbool,Runzhan Zhou,Muhammad Arsalan,Kai Sun,Youbin Si
This study represents one of the first attempts towards bisphenol A (BPA) degradation by Trametes versicolor laccase immobilized on Ba-alginate beads. The effect of input variables including temperature (20–40 °C), BPA concentration (2–10 mg/L) and time (10–90 min) were studied using Box-Behnken design (BBD) and artificial neural network (ANN). The maximum BPA degradation of 84.34% was obtained when the temperature was 40 °C, BPA concentration 2 mg/L and time 50 min, which was accurately predicted by BBD (83.48%) and ANN (84.33%), proving the accuracy of prediction for both models. The values of R 2 and MSE for BBD were found to be 0.98, 9.88, while for ANN were 0.97, 38.25, respectively. Based on higher R 2 value and lower MSE, BBD was slightly better than ANN. The immobilized laccase showed higher storage stability than free laccase by retaining 68.64% and 44.62% of their activity at the same experimental conditions. Furthermore, BPA transformation was confirmed by Fourier-transform infrared spectroscopy (FTIR) analysis. GC-MS had detected the oxidative degradation products from BPA. Results showed that Ba-alginate immobilized laccase could be a promising biocatalyst in treating organic pollutants .
研究领域:
环境科学
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生物技术
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产品关联
DOI
高影响因子
ENVIRONMENTAL POLLUTION
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2020
·
IF 6.793
Kai Sun,Xing Cheng,Jialin Yu,Luojian Chen,Jiajun Wei,Wenjun Chen,Jun Wang,Shunyao Li,Qingzhu Liu,Youbin Si
Estrogens, which are extensive in the eco-environments, are a category of high-toxic emerging contaminants that induce metabolic disorders and even carcinogenic risks in wildlife and humans. Here we investigate whether fungus-secreted laccase can be used as a green catalyst to eliminate a representative estrogen, 17 β -estradiol (E2). A white-rot fungus Trametes hirsuta La-7 with high laccase-productivity, was isolated from pig manure-contaminated soil. Extracellular laccase activity expressed by strain La-7 was 65.4 U·mL −1 for a 3 d inoculation under the optimal fermentation parameters. The concentrated-crude laccase from Trametes hirsuta La-7 (CC- Th Lac) was capable of effectively metabolizing E2 at pH 4–6, and the apparent pseudo first-order reaction rate constant and half-life values were respectively 0.027–0.055 min −1 and 25.86–12.67 min ( R 2 > 0.98). The mass measurement of high-resolution mass spectrometry in combination with 13 C-isotope labeling identified that the main by-products of E2 metabolism were dimers, trimers , and tetramers, which are consistent with radical-driven C–C and/or C–O–C covalent coupling pathway, involving the initial enzymatic production of phenoxy radical intermediates and then the successive oxidative-oligomerization of radical intermediates. The formation of oligomers dramatically reduced the estrogenic activity of E2. Additionally, CC- Th Lac also exhibited high-efficiency metabolism capability toward E2 in the natural water and pig manure, with more than 94.4% and 91.0% of E2 having been metabolized, respectively. These findings provide a broad prospect for the clean biotechnological applications of Trametes hirsuta La-7 in estrogen-contaminated ecosystems.
研究领域:
环境生物学
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生物化学
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生态学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
·
IF 14.224
Kai Sun,Qingzhu Liu,Jie Liu,Shunyao Li,Xuemin Qi,Meihua Chen,Youbin Si,Yanzheng Gao
How humic acid (HA) modifies bisphenol A (BPA) conversion in exoenzyme-activated polyreaction is poorly understood. Herein, the influencing mechanism of HA on laccase-induced BPA self-polymerization was investigated, and the phytotoxicity of the produced BPA self/co-polymers was assessed for the first time. HA prominently boosted BPA elimination, and the rate constants of BPA conversion augmented from 0.61 to 1.43 h −1 as HA level raised from 0 to 50 mg·L −1 . It is because the generated BPA-HA co-polymers promptly lowered the yields of long-chain BPA self-oligomers, consequently maintaining laccase activity through opening enzymatic substrate-binding pockets. Notably, a few BPA monomers were re-released from the loosely bound self-polymers and co-polymers, and the releasing amounts respectively were 13.9 − 22.4% and 0.3 − 0.5% at pH 2 − 11. Formation of self/co-polymers was greatly conducive to avoiding BPA biotoxicity. Compared with BPA self-polymers, the phytotoxicity of BPA co-polymers to germinated radish ( Raphanus sativus L.) seeds was lower due to these covalently bound products were more complex and stable. It follows that laccase-mediated co-polymerization played a significant role in BPA conversion, contaminant detoxification, and carbon sequestration . These findings are not only beneficial to clarifying exoenzyme-activated the generation mechanism of BPA co-polymers in water, but to reusing these supramolecular aggregates in crop growth.
研究领域:
环境科学
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Zeqi Zheng,Weitao Liu,Jiantao Li,Miao Yu,Aurang Zeb,Qixing Zhou,Maohong Lin
Trichloromethane (TCM) in soil causes adverse effects on the soil ecosystem and human health. Therefore, it is urgent to develop an efficient and low-cost soil TCM removal technology. In this study, we prepared sodium alginate-biochar-laccase immobilized pellets (SA-BC-LC) using composite immobilization technology, exploring the fitting impact of artificial neural network model (ANN) and general linear model (GLM) models on laccase loading and the correlation properties of SA-BC-LC. The SA-BC-LC exhibited a porous multi-layer network structure internally. Compared to free laccase, the relative activity of SA-BC-LC remained above 50 % after 5 reuses and still maintained at 48 % after 50 days of storage. Moreover, SA-BC-LC demonstrated significant capacity for adsorption and degradation of TCM in soil with ratios approximately at 31.3 % and 68.7 %, respectively. During the remediation process of TCM-contaminated soil from Taizhou Chemical plant, there was a rapid decrease in TCM concentration within the first hour. Under IM (Immobilization) treatment (added with 5 % SA-BC-LC), the removal rate of TCM reached up to 88.9 % in the first hour. The adsorption of TCM by SA-BC-LC was mainly chemical adsorption, which induced the improvement of the relative abundance of the co-metabolic dechlorinated microbial Pseudomonas . Our research presents a promising material for effectively remediating soils contaminated with chlorinated hydrocarbons (CHs), with excellent removal efficiency.
研究领域:
环境科学
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生物技术
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土壤修复
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2015
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IF 5.33
Junhe Lu,Juan Shao,Hui Liu,Zunyao Wang,Qingguo Huang
Laccases are a type of extracellular enzyme produced by fungi, bacteria, and plants. Laccase can catalyze one-electron oxidation of a variety of phenolic compounds using molecular oxygen as the electron acceptor. In this study, transformation of halophenols (XPs) in laccase-catalyzed oxidation processes was explored. We first examined the intrinsic reaction kinetics and found that the transformation of XPs appeared first order to the concentrations of both XPs and laccase. A numerical model was developed to describe the role of humic acid (HA) in this process. It was demonstrated that HA could reverse the oxidation of XPs by acting as the inner filtrator of XP radical intermediates formed upon reactions between the substrates and laccase. The extent of such reversion was proportional to HA concentration. MS analysis in combination with quantum chemistry computation suggested that coupling products were generated. XPs coupled to each via C—C or C—O—C pathways, generating hydroxyl polyhalogenated biphenyl ethers (OH-PCDEs) and hydroxyl polyhalogenated biphenyls, respectively. Many of these polyhalogenated products are known to be hazardous to the ecosystem and human health, but they are not synthetic chemicals. This study shed light on their genesis in the environmental media.
研究领域:
环境科学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
Applied Sciences-Basel
·
2022
·Vol. 12
·期 21
·11202
·
IF 2.838
Jie Yang,Zhibo Zhou,Tianji Lu,Ling Shen
The present work reports the identification of inorganic and organic materials applied in gildings of Kizil Grottoes mural paintings, located in the western part of China. A total of 10 gold gilding samples were collected from caves dated in the fourth–seventh century AD. In this research, optical microscopy, scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX), UV fluorescence microscopy, and pyrolysis gas chromatography–mass spectrometry (Py-GC/MS) analyses were carried out to clarify the mordant materials and the coating materials on the foils. This research reports some new finds of the gilding technique in Kizil grottoes, such as oil and lac resin being used as mordant to provide a binding medium for gold gilding, gold powder probably being used as pigment, and some organic dyes being well preserved under gold foil. These interesting findings not only provide scientific evidence for us to understand the materials and techniques of gold gildings on Kizil Grottoes murals, but also illustrate material trade and technique exchanges along the Silk Road in the past.Keywords:gilding;lac resin;organic materials;Kizil Grottoes
研究领域:
考古学
·
材料科学
✓ 已验证
DOI
高影响因子
PLoS One
·
2014
·Vol. 9
·期 10
·e109786
·
IF 3.534
Yuling Han,Lili Shi,Jing Meng,Hongbo Yu,Xiaoyu Zhang
Lignocellulose facilitates the fungal oxidization of recalcitrant organic pollutants through the extracellular ligninolytic enzymes induced by lignin in wood or other plant tissues. However, available information on this phenomenon is insufficient. Free radical chain reactions during lignin metabolism are important in xenobiotic removal. Thus, the effect of lignin on azo dye decolorization in vivo by Echinodontium taxodii was evaluated. In the presence of lignin, optimum decolorization percentages for Remazol Brilliant Violet 5R, Direct Red 5B, Direct Black 38, and Direct Black 22 were 91.75% (control, 65.96%), 76.89% (control, 43.78%), 43.44% (control, 17.02%), and 44.75% (control, 12.16%), respectively, in the submerged cultures. Laccase was the most important enzyme during biodecolorization. Aside from the stimulating of laccase activity, lignin might be degraded by E. taxodii, and then these degraded low-molecular-weight metabolites could act as redox mediators promoting decolorization of azo dyes. The relationship between laccase and lignin degradation was investigated through decolorization tests in vitro with purified enzyme and dozens of aromatics, which can be derivatives of lignin and can function as laccase mediators or inducers. Dyes were decolorized at triple or even higher rates in certain laccase–aromatic systems at chemical concentrations as low as 10 µM.
研究领域:
环境生物学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）