CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2023
·
IF 3.8
Xiaoyun Hou,Qinghong Shi
We described a novel polymer-lipase conjugate for high-efficient esterification of vitamin E using vitamin E and succinic anhydride as the substrates in nonaqueous media. In this work, the monomer, N -isopropylacrylamide (NIPAM), was grafted onto Candida rugosa lipase (CRL) to synthesize poly(NIPAM) ( p NIPAM)-CRL conjugate by atom transfer radical polymerization via the initiator coupled on the surface of CRL. The result showed that the catalytic efficiencies of p NIPAM-CRL conjugates (19.5 – 30.3 L·s -1 ·mmol -1 ) were at least 7-times higher than that of free CRL (2.36 L·s -1 ·mmol -1 ) in DMSO. It was attributed to a significant increase in K cat of the conjugates in nonaqueous media. The synthesis catalyzed by p NIPAM-CRL conjugates was influenced by the length and density of the grafted polymer, water content, solvent polarity and molar ratio of the substrates. In the optimal synthesis, the reaction time was shortened at least 7-times, and yields of vitamin E succinate by p NIPAM- g -CRL and free CRL were obtained to be 75.4% and 10.1 % at 55°C after the reaction for 1.5 h. The result argued that conjugation with p NIPAM induced conformational change of the lid on CRL based on hydrophobic interaction, thus providing a higher possibility of catalysis-favorable conformation on CRL in nonaqueous media. Moreover, p NIPAM conjugation improved the thermal stability of CRL greatly, and the stability improved further with an increase of chain length of p NIPAM. At the optimal reaction conditions (55°C and 1.5 h), p NIPAM- g -CRL also exhibited good reusability in the enzymatic synthesis of vitamin E succinate and kept ∼ 70% of its catalytic activity after ten consecutive cycles. The research demonstrated that p NIPAM- g -CRL was a more competitive biocatalyst in the enzymatic synthesis of vitamin E succinate and exhibited good application potential under harsh industrial conditions.
研究领域:
生物技术
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酶工程
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有机化学
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药学
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产品关联
DOI
高影响因子
Molecular Catalysis
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2021
·
IF 5.062
Chao Xu,Hongbo Suo,Yu Xue,Jing Qin,Hongyue Chen,Yi Hu
Four types of amino acid ionic liquids (AAILs) with chiral structure were used to modify Candida antarctica lipase B (CALB). The results showed that the catalytic activity at different temperatures and pH, thermostability, and tolerance to organic solvents of all modified lipases were improved. The composition and configuration of modifiers have great influence on the catalytic performance of the modified lipases. AAILs composed of l -proline exhibited better modification effect than those containing d -proline. The use of [N-AC- l -Pro] [Cl] led to the highest modification degree (47.92 %) of the lipase, which exhibited the highest hydrolytic activity (430.67 U/g), as well as enhanced thermal stability and tolerance to organic solvents. The structure of CALB was characterized by circular dichroism (CD) and fluorescence spectroscopy. It was found that the introduction of a modifier changes the secondary structure of CALB to a certain extent, and the microenvironment around the fluorescent group changed slightly. The structural stability of CALB modified with [N-AC- l -Pro] [Cl] and the mechanism of reaction were studied by molecular dynamics simulations. The molecular dynamics simulations of the native and modified CALB were performed for 20 ns at 300 and 328 K. The simulation results showed that the root mean square deviation (RMSD) and total energy of modified CALB were less than those of native CALB, indicating a more stable structure for the modified CALB. The root mean square fluctuation (RMSF) calculations showed that the rigidity of the modified CALB and the flexibility of the active center region were both enhanced. The solvent accessibility area (SASA) calculations showed that both hydrophilicity and hydrophobicity of the modified enzyme-protein were improved. The increase in radial distribution function (RDF) of water molecules confirmed that the number of water molecules around the active sites was also increased. Thus, the modified CALB has enhanced structural stability and higher hydrolytic activity towards the triglyceride substrates.
研究领域:
生物化学
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酶工程
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计算生物学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2022
·
IF 8.025
Xue Shi,Xiaoli Qin,Yunxiang Dai,Xiong Liu,Weifei Wang,Jinfeng Zhong
The catalytic activity of Candida antarctica lipase B (CALB) immobilized on modified cellulose nanocrystals (CNC) with different hydrophobicity was investigated using experimental and theoretical approaches. Firstly, the modified CNC were characterized by multi-spectroscopic methods, water contact angle, scanning electron microscopy and thermogravimetric analysis. Moderately hydrophobic CNC were found to be an optimal support for CALB immobilization. Secondly, model systems contained a CALB molecule and different numbers of modified CNC molecules ( [email protected] , [email protected] and [email protected] ) were prepared for molecular dynamics (MD) simulation. Root-mean-square fluctuation values (0.61–2.61 Å) of lid region were relatively high in [email protected] , indicating that modified CNC with moderate hydrophobicity favored forming a lid-open conformation of CALB. Finally, the esterification of oleic acid catalyzed by the immobilized CALB showed higher conversion (54.68 %) than free CALB (12.98 %). Insights into modified CNC with tunable properties provided by this study may be a potential support for improving the catalytic performance of lipases.
研究领域:
生物化学
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生物催化
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纳米技术
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材料科学
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酶学
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产品关联
DOI
PubMed
高影响因子
Catalysis Science & Technology
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2018
·Vol. 8
·期 18
·4718-4725
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IF 5.365
Jiang-Wei Shen,Jia-Mei Qi,Xiao-Jian Zhang,Zhi-Qiang Liu,Yu-Guo Zheng
Candida antarctica lipase B (CALB) is a versatile and robust lipase with high activity and enantioselectivity in the resolution of alcohols and amines. Poor specific activity toward carboxylic esters that are branched or substituted in close proximity to the carboxyl group limits the application of CALB. In this study, a semi-rational engineering approach was successfully applied to tailor CALB for efficient synthesis of the moxifloxacin chiral intermediate through enzymatic resolution of cis-(±)-dimethyl 1-acetylpiperidine-2,3-dicarboxylate. The combinatorial active-site saturation test was performed on CALB and two key residue sites, 189 and 190, were identified in the determination of hydrolytic activity. The specific activity and catalytic efficiency (kcat/Km) of the best variant mut-I189K were increased by 286- and 193-fold, respectively, without impacting its enantioselectivity. With 0.1 g L−1 of purified mut-I189K loading, 1 M substrate was asymmetrically hydrolyzed with 49.9% conversion within 5 h, resulting in a space–time yield of 583.8 g L−1 d−1. These results demonstrated that mut-I189K is a competitive biocatalyst for large-scale preparation of the moxifloxacin chiral intermediate.
研究领域:
生物催化
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酶工程
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药物化学
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有机合成
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产品关联
DOI
高影响因子
FOOD AND BIOPRODUCTS PROCESSING
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2024
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IF 3.5
Lu Ren,Yang Hu,Yefei Wu,Mengqian Zhao,Qianqian Ma,Yulu Du,Jianwei Lu,Xuwei Long
Sophorose is a rare and valuable disaccharide with an unusual β -1,2 bond. Despite the relatively widespread interest in sophorose, the information regarding sophorose is limited because sophorose is not readily accessible. Thus, we used Candida bombicola ATCC 22214 for the efficient fermentative production of sophorose using glucose and soybean oil as substrates. In addition, an integrated separation process comprising precipitation, extraction, electrodialysis, and column chromatography was developed to purify the sophorose. Sophorose (approximately 35 g/L) was produced under optimized fermentation conditions in terms of the feeding strategy and enhanced mass-transfer efficiency. Thereafter, approximately 38% of sophorose (purity above 99%) was recovered from fermentation broth through the proposed process. This study provides an efficient approach for the large-scale preparation of sophorose, which is helpful for its practical application and in-depth research.
研究领域:
生物工程
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糖化学
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产品关联
DOI
高影响因子
Foods
·
2023
·Vol. 12
·期 15
·2843
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IF 5.2
Siyu Xue,Naihui Dong,Kexin Xiong,Hui Guo,Yiwei Dai,Huipeng Liang,Yingxi Chen,Xinping Lin,Beiwei Zhu,Sufang Zhang
Ethyl carbamate (EC), a 2A carcinogen produced during the fermentation of foods and beverages, primarily occurs in distilled spirits. Currently, most studies focus on strategies for EC mitigation. In the present research, we aimed to screen strains that can degrade EC directly. Here, we report twoCandida ethanolicastrains (J1 and J116), isolated from fermented grains, which can reduce EC concentrations directly. These two yeasts were grown using EC as the sole carbon source, and they grew well on different carbon sources. Notably, after immobilization with chitosan, the two strains degraded EC in Chinese Baijiu by 42.27% and 27.91% in 24 h (from 253.03 ± 9.89 to 146.07 ± 1.67 and 182.42 ± 5.05 μg/L, respectively), which was better than the performance of the non-immobilized strains. Furthermore, the volatile organic compound content, investigated using gas chromatography-mass spectrometry, did not affect the main flavor substances in Chinese Baijiu. Thus, the yeasts J1 and J116 may be potentially used for the treatment and commercialization of Chinese Baijiu.Keywords:ethyl carbamate (EC);Candida ethanolica;Chinese Baijiu;immobilization
研究领域:
微生物学
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食品科学
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产品关联
DOI
PubMed
高影响因子
WASTE MANAGEMENT
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2023
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IF 8.1
Hongxu Lu,Yanxia Liu,Wenyue Shen,Yang Zhou,Xiangwei Ma,Shibo Sun,Xiaoying Dong,Fengyun Ji,Huiyan Tong,Jianqiang Xu,Gaohong He,Weiping Xu
Food waste can be converted into insectile fatty acids (FAs) by the larvae of black soldier fly (BSFL), Hermetia illucens , for use in the feed sector or as a source of biodiesel. However, waste oil was less decomposed than carbohydrate or protein in frass due to the limitation of larval lipid metabolism. In this study, 10 yeast strains were screened, corresponding to six species, to examine their capacity of improving lipid transformation performance by BSFL. The species of Candida lipolytica was superior to the other five species, which exhibited significantly higher lipid reduction rate (95.0–97.1 %) than the control (88.7 %), and the larval FA yields achieved 82.3–115.5 % of the food waste FA matters, suggesting that BSFL not only transformed waste oil but also biosynthesized FAs from waste carbohydrate and other substances. Further, the CL2 strain of Candida lipolytica was examined for treating food waste containing high lipid content (16–32 %). The lipid removal rate was found improved from 21.4 to 42.3 % (control) to 80.5–93.3% in the waste containing 20–32 % lipid. The upper limit of lipid content that could be endured by BSFL was ≈16 %, and the CL2-enrichment elevated the upper limit to ≈24 %. Fungal community analysis indicated that Candida spp. accounted for the lipid removal improvement. The Candida spp. CL2 strain may facilitate the lipid reduction and transformation by BSFL through microbial catabolizing and assimilation of waste FAs. Altogether, this study suggests that yeast enrichment is feasible in improving lipid transformation by BSFL especially for food waste exhibiting high lipid content.
研究领域:
环境科学
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昆虫学
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微生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL DE MYCOLOGIE MEDICALE
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2018
·
IF 1.606
K. Xu,J.L. Wang,M.P. Chu,C. Jia
Objective The aim of this study was to investigate the antibiofilm activity of coumarin against Candida albicans . Methods The efficacy of coumarin against biofilm formation and the mature biofilm of C. albicans was quantified by crystal violet (CV) staining and the 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) reduction assay. The effect of coumarin on C. albicans adhesion was assessed on polystyrene plates and by using the cell surface hydrophobicity (CSH) assay. The morphological transition of C. albicans was conducted in two types of hyphae-inducing media at 37 °C. The expression of hypha/biofilm-related genes was evaluated using qRT-PCR analysis. A rescue experiment involving addition of exogenous cyclic adenosine monophosphate (cAMP) was performed to investigate the involvement of cAMP in the yeast-to-hyphae transition. A C. albicans -infected Caenorhabditis elegans model was used to test the anti-virulence efficacy of coumarin. Results Treatment with coumarin strongly affected the capacity of C. albicans to form biofilm and significantly impaired the preformed mature biofilm. The addition of coumarin notably inhibited C. albicans adhesion, CSH, and filamentation . The expression of some adhesion- and hypha-related genes, including HWP1 , HYR1 , ECE1 , and ALS3 , was remarkably down-regulated upon exposure to coumarin. Supplementation with cAMP partly rescued the coumarin-induced defects in hyphal development. Finally, coumarin prolonged survival in C. albicans -infected nematodes. Conclusion Coumarin inhibited C. albicans biofilm, which was associated with attenuated adhesion and hyphal growth.
研究领域:
微生物学
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药理学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
BIOFOULING
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2020
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IF 2.351
Juanjuan Liu,Qianqian Li,Changzhong Wang,Jing Shao,Tianming Wang,Daqiang Wu,Kelong Ma,Guiming Yan,Dengke Yin
Traditional herbal monomers (THMs) are widely distributed in many traditional Chinese formulas (TCFs) and decoctions (TCDs) and are frequently used for the prevention and treatment of fungal infections. The antifungal activities of five common THMs, including sodium houttuyfonate (SH), berberine (BER), palmatine (PAL), jatrorrhizine (JAT) and cinnamaldehyde (CIN), and their potential for inducing cell wall remodeling (CWR), were evaluated against Candida albicans SC5314 and Candida auris 12372. SH/CIN plus BER/PAL/JAT showed synergistic antifungal activity against both Candida isolates. Furthermore, SH-associated combinations (SH plus BER/PAL/JAT) induced stronger exposure of β-glucan and chitin than their counterparts, while CIN triggered more marked exposure compared with CIN-associated combinations (CIN plus BER/PAL/JAT). Collectively, this study demonstrated the anti-Candida effect and the CWR induction potential of the five THMs and their associated combinations, providing a possibility of their in vivo application against fungal-associated infections.
研究领域:
药理学
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微生物学
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中医药
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产品关联
DOI
PubMed
高影响因子
FOOD MICROBIOLOGY
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2019
·
IF 4.089
Yunhao Lu,Xinyi Tan,Yuanping Lv,Guohua Yang,Yuanlong Chi,Qiang He
The production of Chinese horse bean-chili-paste (CHCP) involves three fermentation phases: chili-to-moromi fermentation (CF) phase, horse bean-to-meju fermentation (HF) phase and moromi-meju mixed fermentation (MF) phase. To understand the microbial dynamics among these three phases and the potential roles of viable microbes for fermentation, microbial community dynamics was investigated by using culture-dependent and culture-independent methods. Furthermore, the capacities of enzyme-producing of the isolates were determined. During the CF phase, reducing sugar content increased from 3.1% to 3.49%, while pH declined from 4.85 to 4.5. The protein content in the HF phase and MF phase reduced sharply from 22.23% to 10.29% and 4.39%–1.19%, respectively. Bacillus sp., Staphylococcus sp., Oceanobacillus sp., Candida sp., Zygosaccharomyces sp. and Aspergillus sp. dominated the CF phase, while Bacillus sp., Candida sp. and Zygosaccharomyces sp. were the dominant microorganisms in both the HF and MF phases. B. amyloliquefaciens , B. methylotrophicus , B. subtilis, B. licheniformis and A. oryzae possessed strong capacities of producing enzymes, i.e. α -amylase, cellulase and xylanase, acid protease and leucine aminopeptidase , and could make a great contribution to CHCP fermentation.
研究领域:
食品科学
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微生物学
✓ 已验证
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Jun Liang,Huiting Xu,Zhixi Zhang,Yaqian Bian,Qiang Zhang,Weiyi Su,Yuqi Hu,Chunli Li,Xiong Yu,Honghai Wang
Enzymatic processes coupled with continuous microfluidic techniques have significant application prospects in pharmaceuticals and fine chemicals. It is important to stably load enzymes in microreactors. This study reported a sol–gel method for preparing wall-coated immobilized enzyme microreactors (W-IMERs) by entrapment of Candida antarctica lipase B (CALB). The W-IMERs were simply constructed in one step by a flow coating process in a capillary. Compared with the free enzyme, the tolerance of immobilized enzyme to ethanol and temperature is significantly improved, and the yield of immobilized enzyme activity is 76.12% in the batch reactor. In W-IMERs, the yield of immobilized enzyme activity increased to 82.95%. The W-IMERs maintained stable activity in 10 cycles for up to 30 days. A CFD model was also established to explore the relationship between the internal reaction and the mass transfer in W-IMERs. The relationship between the internal and external diffusion limits of W-IMERs and the overall reaction rate was analyzed by dimensionless numbers. The results indicated that sol–gel flow coating is a simple and effective method for the preparation of enzymatic microreactors. An in-depth understanding of the relationship between diffusion limitation and reaction rate will have a significant impact on the overall performance of enzyme-catalyzed microreactors.
研究领域:
生物化学
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生物工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
·
IF 8.5
Le Zhong,Yuxiao Feng,Zichen Wang,Tian Tian,Yali Bi,Jiandong Cui
Enzymatic synthesis of flavor esters is crucial for applications in food, beverage, and cosmetics industries. However, the poor activity and stability of free lipase hinder these reaction. Inspired by the concept of lipase interface activation, MIL-53(Al)-NH 2 was modified with alkyl acid anhydrides of varying chain lengths to tailor its hydrophobicity, and Candida Rugosa lipase (CRL) was subsequently immobilized on this surface to achieve efficient interface activation. The resulting CRL@MIL-53(Al)-AM11 exhibited 3.5 times higher activity than the unmodified CRL@MIL-53(Al)-NH 2 . Moreover, CRL@MIL-53(Al)-AM11 enabled one-step purification of crude CRL via selective adsorption. It also showed enhanced storage and thermal stability as well as higher resistance to protease degradation and denaturants than free CRL. CRL@MIL-53(Al)-AM11 retained 75 % of its initial activity after 30 min treatment at 55 °C, whereas the free CRL retained only 41 %. After 11 days of storage, CRL@MIL-53(Al)-AM11 maintained 70 % of its initial activity, in contrast to 36 % for the free lipase. Notably, CRL@MIL-53(Al)-AM11 achieved a 97 % conversion rate in the esterification synthesis of the flavoring substance (butyl butyrate) within 24 h and retained over 40 % conversion after five consecutive cycles. Therefore, this strategy offers a feasible approach for constructing high-performance immobilized lipases for flavor ester synthesis.
研究领域:
生物化学
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食品科学
·
酶工程
✓ 已验证
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）