JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY
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2013
·Vol. 91
·期 1
·55-62
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IF 1.592
Qin Xiao-Li,Huang Hui-Hua,Lan Dong-Ming,Wang Yong-Hua,Yang Bo
Typoselectivity of crude CBD-T1 lipase ( Geobacillus sp. T1 lipase fused with a cellulose binding domain) was investigated. Multi-competitive reaction mixtures including a set of n -chain fatty acids (C8:0, C10:0, C12:0, C14:0, C18:1 n-9, C18:2 n-6 and C18:3 n-3) and tripalmitin-enriched triacylglycerols were studied in hexane. The crude CBD-T1 lipase discriminated strongly against C18:1 n-9 [competitive factor ( α ) = 0.23] and showed the highest preference for C8:0 ( α = 1). Utilizing the catalytic properties of crude CBD-T1 lipase, acidolysis of soybean oil with C8:0 was selected as a model reaction to investigate the ability of the lipase to produce MLM-type (medium-long-medium) structured lipids. Several reaction parameters (added water amount, reaction temperature, substrate molar ratio and reaction time) examined for incorporating C8:0 into soybean oil, the optimum conditions were: 1:3 (soybean oil/C8:0) of molar ratio, 3 mL of hexane, 50 °C of temperature, 48 h of reaction time, 20 % of crude CBD-T1 lipase (w/w total substrates), and 7.5 % of water (w/w enzyme). Under these conditions, the incorporation of C8:0 was 29.6 mol%. The results suggest that crude CBD-T1 lipase, which showed different fatty acid specificity profiles, is a potential biocatalyst for the modification of fats and oils.
研究领域:
生物化学
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食品科学
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DOI
高影响因子
ENVIRONMENTAL RESEARCH
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2024
·
IF 7.7
Xuran Du,Litao Wang,Hong Liang,Guanyu Chen,Jing Wu,Wenjie Xia,Dawen Gao
Bentonite is a non-metallic mineral with montmorillonite as the main component. It is an environmentally friendly mineral material with large reserves, wide distribution, and low price. Bentonite can be easily modified organically using the surfactant saponin to obtain saponin-modified bentonite (Sap-BT). This study investigates the immobilization of crude enzymes obtained from Trametes versicolor by physical adsorption with Sap-BT. Thus, saponin-modified bentonite immobilized crude enzymes (CE-Sap-BT) were developed to remove benzo[a]pyrene. Immobilization improves the stability of free enzymes. CE-Sap-BT can maintain more than 80% of activity at 45 °C and after storage for 15 d. Additionally, CE-Sap-BT exhibited a high removal rate of benzo[a]pyrene in soil, with 65.69% after 7 d in highly contaminated allotment soil and 52.90% after 6 d in actual soil contaminated with a low concentration of benzo[a]pyrene at a very low laccase dosage (0.1 U/3 g soil). The high catalytic and removal performance of CE-Sap-BT in contaminated sites showed more excellent practical application value.
研究领域:
环境科学
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生物技术
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DOI
PubMed
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
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2024
·
IF 3.4
Jiehu Liu,Runtian Huo,Huixian Fu,Shiheng Chen,Xueyi Qiao,Bo Xu,Zhaoyuan Zhang,Jing Wu,Lingqia Su
β-nicotinamide mononucleotide (β-NMN) is a key precursor of nicotinamide adenine dinucleotide, and becomes attractive in the nutrition and health care fields, but its enzymatic synthesis is expensive. In this study, a six-enzyme cascade catalytic system was constructed to produce β-NMN. Using D-ribose and nicotinamide as substrates, the β-NMN yield reached 97.5 % catalyzed by purified enzymes. Then, after knocking out the genes encoding proteins that consume β-NMN in E. coli BL21(DE3), the similar β-NMN yield, 97.2 %, using the crude enzymes could be also obtained. After that, β-NMN synthesis was performed under increased substrate concentration, and 'modular' crude enzymes cascade catalytic reaction system was proposed to reduce the inhibition of polyphosphate on ribose-phosphate diphosphokinase activity, and the β-NMN yield reached 78.4 % at 10 mM D-ribose, which is 1.82 times of that in 'one-pot' reaction and represents the highest β-NMN preparation level with phosphoribosylpyrophosphate as the core reported till now.
研究领域:
生物化学
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合成生物学
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分子生物学
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DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Dawen Gao,Guanyu Chen,Zelin Hou,Huayu Tao,Xuran Du,Hong Liang
Immobilized crude enzyme with sorption-modified bentonite presents a novel bioremediation strategy for recalcitrant polycyclic aromatic hydrocarbons (PAHs) in contaminated soils. However, the microbial community dynamics under PAH stressors remain unclear. Through a 30-day microcosm experiment using in situ contaminated soil, we systematically evaluated: (i) PAHs removal efficiency, (ii) dissolved organic matter (DOM) fractionation, and (iii) microbiome restructuring across three treatments: natural attenuation with contaminated soil (CK), saponin modified bentonite with contaminated soil (Sap-BT), and immobilized crude enzyme with modified bentonite with contaminated soil (CE-Sap-BT). The results showing that the addition of modified bentonites reached 52.45 % removal rate of Benzo[ a ]pyrene. Increased protein-like component (C1) and two humic-like components (C2 and C3) by 6.69 %, 12.57 % and 18.43 % compared to CK, while immobilized crude enzyme with sorption-modified bentonite enhanced the aerobic function of PAH-degrading microorganisms. Co-occurrence network analysis revealed the strong linkages of soil properties and key bacterial taxa. These results establish that immobilized crude enzyme with sorption-modified bentonite application coupling drives functional microbiome selection, providing novel insights into optimizing in situ PAH remediation protocols.
研究领域:
环境科学
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土壤生物学
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微生物生态学
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DOI
高影响因子
International Journal of Environmental Research and Public Health
·
2022
·Vol. 19
·期 24
·17012
·
IF 4.614
Dingfan Hu,Juan Wu,Luosheng Fan,Shunyao Li,Rong Jia
Complex bacteria communities that comprisedBrevibacillussp. (M1) andAchromobactersp. (M2) with effective abilities of degrading decabromodiphenyl ether (BDE-209) were investigated for their degradation characteristics and mechanisms under aerobic conditions. The experimental results indicated that 88.4% of 10 mg L−1BDE-209 could be degraded after incubation for 120 h under the optimum conditions of pH 7.0, 30 °C and 15% of the inoculation volume, and the addition ratio of two bacterial suspensions was 1:1. Based on the identification of BDE-209 degradation products via liquid chromatography–mass spectrometry (LC–MS) analysis, the biodegradation pathway of BDE-209 was proposed. The debromination, hydroxylation, deprotonation, breakage of ether bonds and ring-opening processes were included in the degradation process. Furthermore, intracellular enzymes had the greatest contribution to BDE-209 biodegradation, and the inhibition of piperyl butoxide (PB) for BDE-209 degradation revealed that the cytochrome P450 (CYP) enzyme was likely the key enzyme during BDE-209 degradation by bacteria M (1+2). Our study provided alternative ideas for the microbial degradation of BDE-209 by aerobic complex bacteria communities in a water system.Keywords:decabromodiphenyl ether;complex bacteria community;degradation efficiency;pathway;crude enzyme;cytochrome P450
研究领域:
环境科学
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微生物学
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生物技术
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DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2019
·
IF 5.589
Ting-Kai Zhu,Pei-Pei Du,Li-Juan Zeng,Huixiong Lü,Hai-Ming Zhao,Yan-Wen Li,Ce-Hui Mo,Quan-Ying Cai
Crops can take up and accumulate di- n -butyl phthalate (DBP), an extensively used plasticizer with endocrine disrupting effect, which poses potential risk to human health. Our previous study found the genotype variation in accumulation of DBP by different cultivars of rice ( Oryza sativa L.). Nevertheless, the effect of DBP metabolism in vivo on the accumulation variation among different plant cultivars remains unknown. In this study, metabolism variation of DBP by low ( Fengyousimiao ) and high ( Peizataifeng ) DBP-accumulating cultivars of rice and the key enzymes involving in DBP metabolism in rice plants were investigated using in vivo exposure of rice plants and in vitro exposure of root crude enzyme extracts. Both mono- n -butyl phthalate (MBP) and phthalic acid (PA) were detected as DBP metabolites in all rice tissues ( i.e. , roots, stems, leaves) and crude enzyme extracts with MBP predominance. DBP metabolism occurred simultaneously when DBP uptake with the highest metabolism in roots in vivo . Degradation of DBP in root crude enzyme extracts fitted well with the first order kinetics ( R 2 = 0.49–0.76, P < 0.05). The activity of carboxylesterase (CXE) in root crude enzyme extracts was significantly positively correlated with DBP degradation rates. CXE played an important role in DBP metabolism of rice plants, confirming by the fact that triphenyl phosphate of CXE inhibitor could inhibit DBP metabolism of in vivo and in vitro exposure. This result was further confirmed by in vitro degradation of DBP with the commercial pure CXE. The crude enzyme solution from roots of Fengyousimiao with higher CXE activity had significantly higher DBP degradation rates than that of Peizataifeng . However, Fengyousimiao with lower tolerance to DBP stress and higher inhibition by triphenyl phosphate displayed lower DBP metabolism ability in vivo than Peizataifeng .
研究领域:
植物学
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环境科学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）