CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Hao Zhou,Yongheng Shi,Lingmei Dai,Dehua Liu,Wei Du
Pyrolyzing ZIF-8 into N-doped carbon is now inspiring new potential of ZIF-8 for extensive applications. However, the exploration of such ZIF-8-derived carbon for biotechnological applications has been rarely investigated, especially in this context that imidazole derivatives are of rich functionality in life science. Herein, we reported a facile temperature-dependent pyrolysis method to achieve the effective N-doping in ZIF-8-derived macroporous carbon, which was systematically investigated for the immobilization of lipase from Thermomyces lanuginosus (TLL) in biodiesel production. MNC-600 (macroporous N-doped carbon derived at 600 °C) exhibited the best immobilization performance, with the highest specific activity of 190.6 U mg −1 , a 36.9% increase than free TLL. Moreover, MNC-600@TLL showed superior effectiveness and robustness in biodiesel production. A much faster rate of conversion and the highest biodiesel yield of 87.4% were observed. After eight successive batches of recycling, MNC-600@TLL retained 93.4% of its initial activity. XPS analysis revealed the evolution of N species during the pyrolysis of ZIF-8. It was proposed that the abundant doping of pyrrolic N species played a major role in the surprising performance of MNC-600, mainly through hydrogen bonding interactions, which simultaneously realized the activation of reactants as well as the in-situ hydrophobization of biocatalyst. This report is anticipated to pave a way for the exploration of ZIF-8-derived N-doped carbon for extensive biotechnological applications.
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高影响因子
ACS Biomaterials Science & Engineering
·
2023
·
IF 5.8
Chang Liu,Qing Yang,Hong Lin,Limin Cao,Kaiqiang Wang,Jianxin Sui
Nowadays, obesity severely impacts human health and is the fifth leading risk factor that leads to death globally. Pancreatic lipase (PL) inhibitors have attracted extensive attention owing to their role in effective prevention and treatment of obesity. Here, a shark-derived single-domain antibody fusion protein was used to inhibit PL for the first time. After biopanning, the heterologous expression system pET28a-SUMO-D2 was constructed using the method of double restriction enzyme digestion and T4 ligase to achieve the soluble expression of the PL-specific antibody gene D2. According to the calculation of protein concentration, the final expression of fusion protein PL-D2S was 1.183 mg per liter of Luria Bertani broth. The binding ability of the soluble fusion protein PL-D2S to PL was identified. Enzyme-linked immunosorbent assay results showed that the fusion protein PL-D2S exhibited a strong binding affinity to PL. The experimental results of PL inhibition of PL-D2S in vitro showed that the fusion protein could significantly inhibit the activity of PL, with an IC50 of 404 μg/mL. Our study shows that the fusion protein PL-D2S is a potential PL inhibitor to prevent and treat obesity.
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PubMed
高影响因子
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.
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高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2019
·Vol. 36
·期 5
·729-739
·
IF 2.476
Pan Jiaying,Ou Zhimin,Tang Lan,Shi Hanbing
Racemic 1-phenylethylamine was resolved by enantiomer selective acetylation using Fe 3 O 4 -chitosan microsphere (CTS)-glutaraldehyde-lipase in a solvent-free system under an alternating magnetic field. Magnetic chitosan microspheres (Fe 3 O 4 -CTS) were prepared via chemical co-precipitation and cross-linked with lipase using glutaraldehyde to form Fe 3 O 4 -CTS-glutaraldehyde-lipase particles. The magnetic, physicochemical, and textural characteristics of Fe 3 O 4 -CTS-glutaraldehyde-lipase particles were assessed by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. The optimal immobilization conditions were 2.4 mg/mL lipase, 10 mg/mL Fe 3 O 4 -CTS-glutaraldehyde, pH 8.5, 35 °C, 3 h. The loading amount of lipase and the specific activity got to 132 mg/g carrier and 48 U/g. The optimal reaction conditions of the acylation reaction using Fe 3 O 4 -CTS-glutaraldehyde-lipase were 300 mmol/L 1-phenylethylamine, 150 mg immobilized lipase, 2 mL vinyl acetate, 12.6 ×g rotating speed, 40 °C, 8 h. The activity of the Fe 3 O 4 -CTS-glutaraldehyde-lipase particles and conversion were improved when they were exposed to an external alternating magnetic field. The optimum magnetic field was 12 Gs (500 Hz). The conversion, enantiomeric excess of ( R )- N -(1-phenylethyl)acetamide, and E value reached 41.8%, 98.4%, and 264, respectively. Fe 3 O 4 -CTS-glutaraldehyde-lipase could be reused seven times. A kinetic model of the immobilized lipase-catalyzed resolution of 1-phenylethylamine was set up based on the ping-pong bi-bi mechanism. The kinetic constants were V max =1.62×10 −2 mM/min, K A =2.84×10 −4 mM, and K B =5.8×10 −1 mM. The model data fit well with the experimental data.
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高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Wei Zhuang,Weiwei Gu,Qianqian Zhu,Jiahua Zhu,Zhenfu Wang,Huanqing Niu,Dong Liu,Jinglan Wu,Yong Chen,Ming Li,Chenjie Zhu,Hanjie Ying
In order to solve the toxic and hazardous issues of the agents in the chemical reduction process of graphene oxide (GO), disodium guanosine 5′-monophosphate (GMP-2Na) was used as an ideal reducing agent for the synthesis of functionalized GO (FGO) for lipase immobilization. At the condition of low amount adsorption of GMP-2Na indicated by the N1s spectra of X-ray photoelectron spectroscopy (XPS), the C/O atomic ratio of the FGO increased from 2.09 to 3.12, indicating the reduction of GO. As the amount of GMP-2Na increased, the intensity of the characteristic peak of GO in the XRD pattern decreased, and the I D /I G peak intensity of Raman spectra increased during the functionalization process. It was found that when the concentration of GMP-2Na is 0.20 mg/mL, the degree of hydrophobicity of FGO is conducive to the formation of optimal conformation of lipase. After immobilization, the activity of the immobilized enzyme reaches twice the value of free enzyme. At the same time, the protein loading reaches to 600 mg/g. The immobilized enzyme showed enhanced durability since no obvious decrease was observed after incubation for 8 h at pH 6.0 and pH 7.0. After storage for 35 days, the activity of GO-G@ enzyme was 54.47% higher than that of free enzyme. GO reduced by GMP-2Na provides a possibility to obtain a highly efficient lipase immobilization carrier.
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Catalysts
·
2018
·Vol. 8
·期 3
·96
·
IF 3.465
Miaad Adnan,Kai Li,Li Xu,Yunjun Yan
This study presents a one-step encapsulation method for synthesizing X-shaped zeolitic imidazolate frameworks (ZIF-8) and immobilizingRhizomucor mieheilipase (RML). We proved that the morphological structure of ZIF-8 had changed after immobilization with enhanced characterization using a field-emission scanning electron microscope, an energy-dispersive spectrometer, a transmission electron microscope, a Fourier transform infrared spectrometer, and powder X-ray diffraction. The surface area and pore size of the carrier were investigated before and after immobilization using Brunauer–Emmett–Teller and Barrett–Joyner–Halenda methods, respectively. RML@ZIF-8 exhibited high recovery activity of up to 2632%, representing a 26-fold increase in its free lipase. Encapsulated RML was used for biodiesel production from soybean oil in an isooctane system with a conversion yield of 95.6% under optimum conditions. The resulting reusability of the immobilized enzyme indicated no substantial decline in the conversion yield, which remained at 84.7% of the initial activity after 10 cycles. The stability and high performance of the immobilized enzyme are attributed to the harmony between RML and ZIF-8 based on the easy synthesis of ZIF-8 and the short time required to immobilize RML.Keywords:X-shape ZIF-8;Rhizomucor mieheilipase (RML);encapsulation technique;biodiesel yield;soybean oil
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高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2018
·
IF 3.909
Hongbo Suo,Lili Xu,Chao Xu,Hongyue Chen,Dinghua Yu,Zhen Gao,He Huang,Yi Hu
Magnetic chitosan nanocomposites were designed and fabricated by combining the magnetic nanoparticles Fe 3 O 4 and chitosan covalently modified by imidazole-based ionic liquids with various functional groups, to be utilized as a support matrix for immobilization of porcine pancreatic lipase (PPL). Ionic liquids modified chitosan was characterized with nuclear magnetic resonance (NMR) and the nanocomposites were characterized with Fourier transform infrared spectroscopy (FTIR), vibrating-sample magnetometer (VSM), thermogravimetry analysis (TGA), Transmission electron microscope (TEM) and Scanning electron microscopy (SEM). The enzymatic properties of PPL were significantly improved by immobilization onto all thus prepared nanocomposites, and among the supports, modified with ionic liquids bearing hydroxyl group exhibited relatively enhanced performance. Particularly, the MCS-IL(8C)-OH-PPL exhibited the highest specific activity which was 6.68 times that of free PPL, and the residual activity of MCS-IL(8C)-OH-PPL remarkably maintained 91.5% of its initial activity even after 10 repeated cycles. The residual activity of MCS-IL(8C)-OH-PPL retained 55.8% after incubated in 6 M urea solution for 1 h and maintained the noticeable initial activity of 75.5% after incubated in phosphate buffer at 50 °C with pH 7.5 for 6 h. In conclusion, the study demonstrated that Fe 3 O 4 @Chitosan nanocomposites modified with functional ionic liquids could be utilized as a novel nanosupport for enzyme immobilization .
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高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2017
·
IF 2.502
Kun Zhang,Zhiyou Pan,Zhoujian Diao,Shuli Liang,Shuangyan Han,Suiping Zheng,Ying Lin
Kinetic resolution of sec -alcohols is a green process with biocatalyst. Candida antarctica lipase B (CALB) displayed on Pichia pastoris cell-surface (Pp-CALB) was characterized in kinetic resolution of sec -alcohols with different structures. The reaction parameters including acyl donors, molar ratio of substrates, solvents and temperatures were examined with 2-octanol as model substrate. 47.4% molar conversion of 2-octanol and 99.7% ee p were obtained after a 5 h reaction with Pp-CALB, and 90% of its original activity still remained after being reused for 10 cycles. Pp-CALB was then used to several sec -alcohols and it showed great enzymatic activity and enantioselectivity to all tested sec -alcohols, more than 93.1% of ee p . The enantioselective characteristics of Pp-CALB catalysed sec -alcohols with different structures were compared with Novozyme 435 which was almost the same. Solvent free system as one way of green chemistry was applied to Pp-CALB and Pp-CALB showed great catalytic activity and enantioselectivity. Pp-CALB was potential biocatalyst of high enzymatic activity and enantioselectivity using in resolution of sec -alcohols.
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高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2017
·Vol. 18
·期 7
·1535
·
IF 3.226
Fanghua Wang,Hui Zhang,Zexin Zhao,Ruixia Wei,Bo Yang,Yonghua Wang
Using the classical emulsified system and the monomolecular film technique, the substrate specificity of recombinantGibberella zeaelipase (rGZEL) that originates fromGibberella zeaewas characterized in detail. Under the emulsified reaction system, both phospholipase and glycolipid hydrolytic activities were observed, except for the predominant lipase activity. The optimum conditions for different activity exhibition were also determined. Compared with its lipase activity, a little higher ratio of glycolipid hydrolytic activity (0.06) than phospholipase activity (0.02) was found. rGZEL preferred medium chain-length triglycerides, while lower activity was found for the longer-chain triglyceride. Using the monomolecular film technique, we found that the preference order of rGZEL to different phospholipids was 1,2-diacyl-sn-glycero-3-phospho-l-serine (PS) > 1,2-dioleoyl-sn-glycero-3-phospho-rac-(1-glycerol) sodium salt (PG) > 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) >l-α-phosphatidylinositol (PI) > cardiolipin (CL) > 3-sn-phosphatidic acid sodium salt (PA) >l-α-phosphatidylethanolamine (PE), while no hydrolytic activity was detected for sphingomyelin (SM). Moreover, rGZEL showed higher galactolipase activity on 1,2-distearoyimonoglactosylglyceride (MGDG). A kinetic study on the stereo- and regioselectivity of rGZEL was also performed by using three pairs of pseudodiglyceride enantiomers (DDGs). rGZEL presented higher preference for distal DDG enantiomers than adjacent ester groups, however, no hydrolytic activity to thesn-2 position of diglyceride analogs was found. Furthermore, rGZEL preferred the R configuration of DDG enantiomers. Molecular docking results were in concordance with in vitro tests.Keywords:Gibberella zeaelipase;substrate specificity;monomolecular film technology;stereospecificity;molecular docking
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高影响因子
MATERIALS RESEARCH BULLETIN
·
2015
·
IF 2.288
Chuan-Yang Shang,Wei-Xun Li,Rui-Feng Zhang
ZnO nanowires were successfully introduced into a macroporous SiO 2 by in-situ hydrothermal growth in 3D pores. The obtained composites were characterized by SEM and XRD, and used as supports to immobilize Candida rugosa lipase (CRL) through adsorption. The high specific surface area (233 m 2 /g) and strong electrostatic interaction resulted that the average loading amount of the composite supports reached 287.2 mg/g. Both adsorption capacity and the activity of the CRL immobilized on the composite supports almost kept unchanged as the samples were soaked in buffer solution for 48 h. The immobilized CRL exhibited better thermal stability, reusability and pH adaptability in comparison to free CRL. The immobilized CRL was used as biocatalyst for the preparation of phytosterol esters by the esterification of phytosterol and oleic acid. A maximum molar conversion of 96.5% was achieved under the optimal condition. After twelve recycles the immobilized lipase could retain 89.9% of its initial activity.
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高影响因子
SOLID STATE SCIENCES
·
2014
·
IF 1.679
Lijun Dong,Chunling Ge,Peiyong Qin,Yan Chen,Qinghong Xu
In this study, MgAl-LDHs (layered double hydroxides) intercalated with sodium dodecyl sulfate and outside surface modified with (3-aminopropyl)triethoxysilane (KH550) were prepared. The existence of organic part in LDHs improved immobilization efficiency and activity recovery of candida lipolytic lipase loaded. Also the positive charge in framework of LDHs was found to be beneficial to the enzyme immobilization. An immobilization efficiency of 56.4% and an activity recovery over 69.2% of the enzyme were obtained after it was loaded on the intercalated and modified LDHs, and catalytic activity of the immobilization can be kept at least five times. Moreover, the immobilized enzyme was found to have higher temperature resistance, wider pH value and better thermostability in reactive activity.
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高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2013
·Vol. 172
·期 2
·701-712
·
IF 1.893
Cui Yanjun,Chen Xia,Li Yanfeng,Liu Xiao,Lei Lin,Zhang Yakui,Qian Jiayu
Using emulsion copolymer of styrene (St), glycidyl methacrylate (GMA) and 2-hydroxyethyl methacrylate (HEMA) as seed latexes, the superparamagnetic polymer emulsion particles were prepared by seeded emulsion copolymerization of butyl methacrylate (BMA), vinyl acetate (VAc) and ethylene glycol dimethacrylate in the presence of the seed latexes and superparamagnetic Fe 3 O 4 /SiOx nanoparticles (or Fe 3 O 4 -APTS nanoparticles) through a two-step process, without addition of any emulsifier. The magnetic emulsion particles named P(St-GMA-HEMA)/P(BMA-VAc) were characterized by transmission electron microscope and vibrating sample magnetometry. The results showed that the magnetic emulsion particles held a structure with a thinner shell (around 100 nm) and a bigger cavity (around 200 nm), and possessed a certain level of magnetic response. The resulting magnetic emulsion particles were employed in the immobilization of lipase by two strategies to immobilized lipase onto the resulting magnetic composites directly (S-1) or using glutaraldehyde as a coupling agent (S-2), thus, experimental data showed that the thermal stability and reusability of immobilized lipase based on S-2 were higher than that of S-1.
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高影响因子
危险品化学品经营许可证（带存储）