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Lipase and photodecarboxylase coexpression: A potential strategy for alkane-based biodiesel production from natural triglycerides
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作者 Yong-Yi Zeng Xin-Yi Xu +4 位作者 Jin-Xuan Xie Wen-Li Chen Lan Liu Xin-Jian Yin Bi-Shuang Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期238-246,共9页
Alkane-based biodiesel is considered the next generation of biodiesel owing to its potential environmental benefits and the fact that it exhibits much higher specific caloric values than traditional biodiesel.However,... Alkane-based biodiesel is considered the next generation of biodiesel owing to its potential environmental benefits and the fact that it exhibits much higher specific caloric values than traditional biodiesel.However,the formidable obstacle impeding the commercialization of this cutting-edge fuel alternative lies in the cost associated with its production.In this study,an engineered strain Escherichia coli(E.coli)showcasing harmonized coexpression of a lipase(from Thermomyces lanuginosus lipase,TLL)and a fatty acid photodecarboxylase(from Chlorella variabilis,CvFAP)was first constructed to transform triglycerides into alkanes.The potential of E.coli BL21(DE3)/pRSFDuet-1-TLL-CvFAP for alkane synthesis was evaluated with tripalmitin as a model substrate under various process conditions.Following a comprehensive examination of the reaction parameters,the scope of the biotransformation was expanded to‘real’substrates(vegetable oils).The results showed that bioderived oils can be transformed into alkanes with high yields(0.80-10.20 mmol·L^(-1))under mild conditions(35℃,pH 8.0,and 36 h)and blue light illumination.The selected processes were performed on an increased lab scale(up to 100 ml)with up to 24.77 mmol·L^(-1) tripalmitin,leading to a yield of 18.89 mmol·L^(-1) pentadecane.With the employment of a method for efficiently producing alkanes under mild conditions and a simple procedure to isolate alkanes from the reaction system,the utilization of sustainable biomass as a fundamental feedstock emerges as the primary solution to lower the cost of alkane-based biodiesel.Thus,this study proposes a readily implementable and highly effective approach for alkane-based biodiesel production. 展开更多
关键词 Alkane-based biodiesel Renewable biomass Co-overexpression lipase Photodecarboxylase
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Bound lipase:an important form of lipase in rice bran (Oryza sativa) 被引量:1
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作者 Chengwei Yu Bin Peng +1 位作者 Ting Luo Zeyuan Deng 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1779-1787,共9页
Rice bran residue possessed a steady lipase activity((26.68 ± 3.69)%)after its endogenous lipase was extracted continuously by phosphate buffer solution(PBS)for 24 h. T herefore, the aim of this research was to e... Rice bran residue possessed a steady lipase activity((26.68 ± 3.69)%)after its endogenous lipase was extracted continuously by phosphate buffer solution(PBS)for 24 h. T herefore, the aim of this research was to explore whether there exist any bound lipases in rice bran(Oryza sativa). Three physical treatments(grinding, homogenizing and ultrasound crush)and 6 enzymatic treatments(cellulase, hemicellulase, pectinase, complex cellulase, glucoamylase and α-amylase)were applied to rice bran in order to investigate this bound lipase. The relative catalytic activities of extraction supernatant and residue for pectinase group were(437.63 ± 22.54)% and(159.26 ± 2.12)%, respectively, which were significantly higher(P < 0.05)than other groups. This phenomenon demonstrated that lipase was the most likely to combine with pectin. Molecular simulation proved that pectin could combine with two rice bran lipases(lipase 315 and lipase 308)and cover the catalytic centers so as to prevent the lipases from encountering the substrate and inhibiting their catalytic activities. During combination, pectin could make the lipases more compact and reduce the solvent accessible surface area of lipases, which would make the lipases inactive to molecular interaction. In summary, part of rice bran lipase was proved to exist in bound form and combined with the pectin. 展开更多
关键词 Rice bran Bound lipase PECTIN Catalytic activity
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Facile Preparation of Dopamine-Modified Magnetic Zinc Ferrite Immobilized Lipase for Highly Efficient Synthesis of OPO Functional Lipid 被引量:1
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作者 Xue Huang Zeyu Chen +1 位作者 Ruizhao Yang Guangzhu Feng 《Journal of Renewable Materials》 SCIE EI 2023年第5期2301-2319,共19页
1,3-Dioleoyl-2-palmitoylglycerol(OPO)has been a hotspot of functional oils research in recent years,but due to the high cost of sn-1,3 specific lipase in enzymatic synthesis and the lack of biocatalyst stability,large... 1,3-Dioleoyl-2-palmitoylglycerol(OPO)has been a hotspot of functional oils research in recent years,but due to the high cost of sn-1,3 specific lipase in enzymatic synthesis and the lack of biocatalyst stability,large-scale industrial application is difficult.In this study,the prepared magnetic ZnFe_(2)O_(4) was functionalized with dopamine to obtain ZnFe_(2)O_(4)@PDA,and the nano-biocatalyst ZnFe_(2)O_(4)@PDA@RML was prepared by immobilizing sn-1,3 specific lipase of Rhizomucor miehei lipase(RML)via a cross-linking method.The existence of RML on ZnFe_(2)O_(4)@PDA was confirmed by XRD,FTIR,SEM,and TEM.This strategy proved to be simple and effective because the lipase immobilized on magnetic nanoparticles could be quickly recovered using external magnets,enabling reuse of the lipase.The activity,adaptability to a high temperature,pH value,and operational stability of immobilized RML were superior to those of free RML.After optimizing the synthesis conditions,the OPO yield was 42.78%,and the proportion of PA at the sn-2 position(PA-Sn2)was 54.63%.After the first four cycles,the activity of ZnFe_(2)O_(4)@PDA@RML was not significantly affected.The magnetically immobilized lipase has good thermal stability,long-term storage stability,reusability,and high catalytic activity.It can be used as a green and efficient biocatalyst to synthesize the OPO functional lipid. 展开更多
关键词 POLYDOPAMINE immobilized lipase 1 3-dioleoyl-2-palmitoylglycerol functional lipid
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Conjugation of Candida rugosa lipase with hydrophobic polymer improves esterification activity of vitamin E in nonaqueous solvent
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作者 Xiaoyun Hou Qinghong Shi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第10期182-191,共10页
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(... 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)(pNIPAM)-CRL conjugate by atom transfer radical polymerization via the initiator coupled on the surface of CRL.The result showed that the catalytic efficiencies of pNIPAM-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 Kcat of the conjugates in nonaqueous media.The synthesis catalyzed by pNIPAM-CRL co njugates 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 pNIPAM-g-CRL and free CRL were obtained to be 75.4%and 6.6%at 55℃after the reaction for 1.5 h.The result argued that conjugation with pNIPAM 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,pNIPAM conjugation improved the thermal stability of CRL greatly,and the stability improved further with an increase of chain length of pNIPAM.At the optimal reaction conditions(55℃and 1.5 h),pNIPAM-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 pNIPAM-g-CRL was a more competitive biocatalyst in the enzymatic synthesis of vitamin E succinate and exhibited good application potential under harsh industrial conditions. 展开更多
关键词 Candida rugosa lipase POLYMERS BIOCATALYSIS ESTERIFICATION Vitamin E succi
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Changes in Lipoprotein Lipase in the Heart Following Diabetes Onset
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作者 Chae Syng Lee Yajie Zhai Brian Rodrigues 《Engineering》 SCIE EI CAS CSCD 2023年第1期19-25,共7页
Due to its constant pumping and contraction, the heart requires a substantial amount of energy, with fatty acids (FAs) providing a major part of its adenosine triphosphate (ATP). However, the heart is incapable of mak... Due to its constant pumping and contraction, the heart requires a substantial amount of energy, with fatty acids (FAs) providing a major part of its adenosine triphosphate (ATP). However, the heart is incapable of making this substrate and attains its FAs from multiple sources, including the action of lipoprotein lipase (LPL). LPL is produced in cardiomyocytes and subsequently secreted to its heparan sulfate proteoglycan (HSPG) binding sites on the plasma membrane. To then move LPL to the endothelial cell (EC) lumen, glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1) attaches to interstitial LPL and transfers it to the vascular lumen, where the LPL is ready to perform its function of breaking down circulating triglycerides (TG) into FAs. The endo-β-glucuronidase heparanase (Hpa) is unique in that it is the only known mammalian enzyme to cleave heparan sulfate (HS), thereby promoting the abovementioned release of LPL from the cardiomyocyte HSPG. In diabetes, it has been suggested that changes in how the heart generates energy are responsible for the development of diabetic cardiomyopathy (DCM). Following moderate diabetes, with the reduction in glucose utilization, the heart increases its LPL activity at the vascular lumen due to an increase in Hpa action. Although this adaptation might be beneficial to compensate for the underutilization of glucose by the heart, it is toxic over the long term, as harmful lipid metabolite accumulation, along with augmented FA oxidation and thus oxidative stress, leads to cell death. This coincides with the loss of a cardioprotective growth factor—namely, vascular endothelial growth factor B (VEGFB). This review discusses interconnections between Hpa, LPL, and VEGFB and their potential implications in DCM. Given that mechanism-based therapeutic care for DCM is unavailable, understanding the pathology of this cardiomyopathy, along with the contribution of LPL, will help us advance its clinical management. 展开更多
关键词 Cardiac metabolism Lipopr otein lipase HEPARANASE Vascular endothelial growth factor Diabetic car diomyopathy
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Novel Lipase from Golden Pompano(Trachinotus ovatus)Viscera:Purification,Characterization,and Application in the Concentrating of n-3 Polyunsaturated Fatty Acids
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作者 LIU Hongxia LIU Shucheng +4 位作者 ZHANG Xueying LIU Zhongyuan LI Chuan XIA Guanghua SHEN Xuanri 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第2期501-508,共8页
Lipases have been widely applied in a variety of industrial fields,such as food,pharmaceuticals,biofuels,and biotechnology.Recent years have witnessed a great interest in modifying lipids for the production of triacyl... Lipases have been widely applied in a variety of industrial fields,such as food,pharmaceuticals,biofuels,and biotechnology.Recent years have witnessed a great interest in modifying lipids for the production of triacylglycerols enriched with n-3 polyunsaturated fatty acids(PUFAs).Here,a novel salt-tolerant,organic solvent-stable,and bile salt-activated lipase was purified from golden pompano(Trachinotus ovatus)viscera,which was named as golden pompano lipase(GPL).GPL had a specific activity of 57.2U mg^(-1)with an estimated molecular weight of 14 k Da,exhibited optimal activity at 40℃a nd pH 8.0,and showed K_(m)and V_(max)of 40.16μmol L^(-1)and 769.23μmol L^(-1)min^(-1),respectively.GPL activity was enhanced by Mn^(2+)and sodium deoxycholate.It was active in organic solvents,including methanol,ethanol,chloroform,and hexane.GPL also showed a good salinity tolerance of up to 1 mol L^(-1).n-3PUFA enrichment in the glyceride fraction of golden pompano oil was performed by GPL-catalyzed hydrolysis and yielded a total PUFA concentration of 56.99%.EPA,DHA,and DPA were enriched by 10.4-,3.2-,and 1.8-fold of their initial levels,respectively.This study recognized the industrial applicability of GPL to prepare enriched C_(20-22)n-3 PUFA. 展开更多
关键词 golden pompano lipase CHARACTERIZATION n-3 polyunsaturated fatty acids
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Encapsulation of lipases on coordination polymers and their catalytic performance in glycerolysis and esterification
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作者 Can Zeng Nanjing Zhong 《Grain & Oil Science and Technology》 CAS 2023年第3期113-119,共7页
In this study,lipases of CALB(Candida antarctica lipase B),TLL(Thermomyces lanuginosa lipase),RML(Rhizomucor miehei lipase),CALA(Candida antarctica lipase A)and LU(Lecitase?Ultra)were encapsulated into the nucleotideh... In this study,lipases of CALB(Candida antarctica lipase B),TLL(Thermomyces lanuginosa lipase),RML(Rhizomucor miehei lipase),CALA(Candida antarctica lipase A)and LU(Lecitase?Ultra)were encapsulated into the nucleotidehybrid metal coordination polymers(CPs)for diacylglyerols(DAG)preparation.Guanosine 5'-monophosphate(GMP)and adenosine 5'-monophosphate(AMP)were used as coordinating molecules,and metal ions of Fe^(3+),Ba^(2+),Mn^(2+),Ni^(2+)and Cr^(3+)were applied to prepare matrix.Results indicated that,besides Ba^(2+)with AMP,all other metal ions can coordinate with AMP and GMP to generate CPs.In addition,the AMP/Ni was amorphous when standing temperature was 4℃,while it was crystalline when standing temperature was from 30 to 180℃.DAG content from 47.55%to 64.99%was obtained from glycerolysis by CALB@GMP/Ba,RML@GMP/Ba,TLL@GMP/Ba,RML@GMP/Mn and TLL@GMP/Mn.Additionally,CALB@GMP/Fe showed selectivity towards DAG formation in the esterification and DAG content up to 61.88%was obtained. 展开更多
关键词 lipase Coordination polymers ENCAPSULATION GLYCEROLYSIS ESTERIFICATION
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Prokaryotic Expression of Pseudomonas Aeruginosa Lipase Gene 被引量:7
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作者 张煜星 武寒雪 +2 位作者 祝建波 刘焕 周鹏 《Agricultural Science & Technology》 CAS 2008年第5期59-62,共4页
[Objective] The aim of this study was to investigate the prokaryotic expression of pseudomonas aeruginosa Lipase gene.[Method]Lipase gene was amplified by PCR from the genome DNA of pseudomonas aeruginosa,and its nucl... [Objective] The aim of this study was to investigate the prokaryotic expression of pseudomonas aeruginosa Lipase gene.[Method]Lipase gene was amplified by PCR from the genome DNA of pseudomonas aeruginosa,and its nucleotide sequence was determined.The prokaryotic expression vector of Lipase gene was constructed by the gene recombination technique.The protein expression was induced for 4 hours by IPTG with the final concentration of 1.0 mmol/L,and then SDS-PAGE electrophoresis was analyzed.[Result]The sequence of mature peptides in Lipase gene cloned from pseudomonas aeruginosa had a 99.36% homology with that of pseudomonas aeruginosa lipase submitted in NCBI,so the prokaryotic expression vector of Lipase gene pET32a-Lip was successfully constructed.Furthermore,the results of SDS-PAGE electrophoresis showed that the target gene was expressed highly and effectively.[Conclusion]The cloned pseudomonas aeruginosa lipase with its signal peptide could be normally expressed in E.coli and also used for further study. 展开更多
关键词 PSEUDOMONAS AERUGINOSA lipase PROKARYOTIC EXPRESSION
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Genetic Screening of the Lipoprotein Lipase Gene for Mutations in Chinese Subjects with or without Hypertriglyceridemia 被引量:3
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作者 杨宇虹 穆云祥 +4 位作者 赵郁 刘新宇 赵莉莉 汪军梅 解用虹 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第5期381-391,共11页
Objective: To investigate the association between the mutations in lipoprotein lipase gene and hypertriglyceridemia (HTG). Methods: The lipoprotein lipase (LPL) gene was screened for mutations in 386 Chinese sub... Objective: To investigate the association between the mutations in lipoprotein lipase gene and hypertriglyceridemia (HTG). Methods: The lipoprotein lipase (LPL) gene was screened for mutations in 386 Chinese subjects with (108 cases in the HTG group) or without HTG (278 cases in the control group), by single-strand conformation polymorphism (SSCP) analysis and DNA sequencing. Results: One novel silent mutation L103L, one missense mutation P207L, three splicing mutations Int3/3' -ass/C(-6)→T, and the common S447X polymorphism has been identified in the whole coding region and exon-intron junctions of the LPL gene were examined. Heterozygous P207L found in the HTG group was the first case reported in Asia and subsequently another P207L heterozygote was found in the proband's family, all of which suggested that P207L was one of the causes of familial combined hyperlipidemia, but was not so prevalent as that in French Canadian. Int3/3'-ass/C(-6)→T was found in both groups in the present study although it was regarded as a pathogenic variant to HTG earlier on. Moreover about the beneficial polymorphism S447X, there was also some supportive evidence that the levels of triglycerides (TG) in S447X carriers were significantly lower than noncarders in the subjects without HTG. Conclusions: The association between the LPL variants and HTG is quite complicated and versatile, genotyping of LPL in a larger-scale screening should be necessary and justifiable. 展开更多
关键词 lipoprotein lipase MUTATIONS CHINESE HYPERTRIGLYCERIDEMIA
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Fermentation Performance and Characterization of Cold-Adapted Lipase Produced with Pseudomonas Lip35 被引量:2
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作者 YU Hong-wei HAN Jun LI Ning QIE Xiao-sha JIAYing-min 《Agricultural Sciences in China》 CAS CSCD 2009年第8期956-962,共7页
Strain of Pseudomonas Lip35 producing lipase was isolated in a refrigerator. Lipase production and characterization of this strain were investigated under different conditions. The Pseudomonas was cultivated in shakin... Strain of Pseudomonas Lip35 producing lipase was isolated in a refrigerator. Lipase production and characterization of this strain were investigated under different conditions. The Pseudomonas was cultivated in shaking flasks in a fermentation medium in various nutritional and physical environments. Lipase production has been influenced by the presence of yeast-extract, soybean powder, NaCI, and Tween-80. Maximum lipase productivity was obtained when the physical environment of the fermentation medium was optimal for 67 h. The production of lipase reached 58.9 U·mL^-1. The lipase of Pseudomonas Lip35 can be considered to be inducible, but the inducer had little influence on the production of lipase. The lipase was characterized and showed high lipolytic activity from pH 7.5-8.0. The optimum temperature was observed at 20℃ and the thermal inactivation of lipase was obvious at 60℃. The lipase activity was inhibited by K+, stimulated by Ca^2+, and thermostability decreased in the presence of Ca^2+, therefore the lipase was Ca^2+ -dependent cold-adapted enzyme. 展开更多
关键词 cold-adapted lipase fermentation optimization lipase characterization Pseudomonas Lip35
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Two rare cases of benign hyperlipasemia in children
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作者 Elena Lionetti Ruggiero Francavilla +4 位作者 Salvatore Leonardi Stefania Tomarchio Alessia Gennaro Chiara Franzonello Mario La Rosa 《World Journal of Clinical Cases》 SCIE 2014年第1期16-19,共4页
Gullo's syndrome is a newly identified condition characterized by a chronic elevation of pancreatic amylase and/or lipase in the absence of pancreatic disease. Until now, only one case of benign isolated hyperlipa... Gullo's syndrome is a newly identified condition characterized by a chronic elevation of pancreatic amylase and/or lipase in the absence of pancreatic disease. Until now, only one case of benign isolated hyperlipasemia in children has been recorded. We describe two children with benign and not familial increase of serum lipase. Case 1: a six year old girl presented with occasional discovery of serum lipase elevation. Medical history was silent for pancreatic hyperenzymemia. The screening for possible causes for elevated lipase(genetic, autoimmune and infectious diseases) was normal. The serum lipase increased three fold over the upper limit(193 U/L; reference range 0-60 U/L), with daily fluctuation of values. Both ultrasound scan and magnetic resonance imaging were normal. The genetic mutation associated with chronic pancreatitis was negative. We followed up this patient for two years with blood tests every six months and she did not show any signs or symptoms of pancreatic disease, except for the high level of lipase serum. Case 2: an eight year old girl complained of nausea, vomiting and severe abdominal pain in theepigastric region after eating for the last two weeks. Full blood count, electrolytes, C-reactive protein, liver and renal function were normal. Serum lipase was 96 U/L(reference range 0-60 U/L). The screening for the possible causes of pancreatic disease was negative. Endoscopy of the upper gastrointestinal tract, ultrasound, computed tomography scan and magnetic resonance imaging were normal. One year after the presentation of the symptoms, the patient became asymptomatic although the level of serum lipase continued to be high. 展开更多
关键词 AMYLASE lipase PANCREATIC hyperenzymemia Gullo’s SYNDROME BENIGN hyperlipasemia
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Lipase and Phospholipase in the Hydrolysis of Lipids in Wastewater from Swine Slaughterhouse and Subsequent Biological Treatment Study
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作者 Aniela Pinto Kempka Rafael Celuppi Jaime Humberto Palacio Revello 《Journal of Agricultural Science and Technology(A)》 2013年第10期757-765,共9页
Wastewaters from slaughterhouses are characterized by a high concentration of oils and greases that can cause problems in conventional treatments. The degradation of difficult pollutants in more easily degradable prod... Wastewaters from slaughterhouses are characterized by a high concentration of oils and greases that can cause problems in conventional treatments. The degradation of difficult pollutants in more easily degradable products can be mediated by enzymes. Enzymatic hydrolysis facilitates the biodegradation because it makes the organic material is made available as compounds of lower molecular weight, the lipids being made available in the form of free fatty acids. The application of enzymes as processing aids in wastewater treatment has some advantages, such as the specificity that allows control of the products, which leads to increased income generation for the non-toxic byproducts and moderate conditions of operation. The objective of this work was optimizing the conditions for lipids enzymatic hydrolysis present in swine slaughterhouse wastewaters using lipolytic enzymes and subsequent biological treatment study. Temperature, pH and enzyme concentration were the variables tested. The enzymes showed good activity and could therefore be used for the hydrolysis process proposed here. The optimized conditions to maximize the release of fatty acids were: temperature of 36 ℃, pH 8.5 and enzyme concentration of 1.1%, yielding fatty acids in the order of 31.50μmol/mL for lipase and 31.13 μmol/mL for phospholipase. All variables influenced the release of fatty acids. The maximum yield of biogas was 89.65 mL in the reactor added the sludge, raw wastewater and phospholipase in the conditions optimized the hydrolysis step, obtaining a chemical oxygen demand (COD) reduction of 90.01% in relation to the value of the COD of the raw wastewater. 展开更多
关键词 WASTEWATER HYDROLYSIS LIPIDS lipase PHOSPHOlipase biological treatment.
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Synthesis of Vitamin A Esters by Immobilized Candida sp. Lipase in Organic Media 被引量:19
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作者 尹春华 刘涛 谭天伟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第1期81-86,共6页
Vitamin A ester was synthesized in organic solvents with immobilized lipase from Candida sp. The types of lipases, influences of solvent, the molar ratio of substrates, the reaction temperature and the water activity ... Vitamin A ester was synthesized in organic solvents with immobilized lipase from Candida sp. The types of lipases, influences of solvent, the molar ratio of substrates, the reaction temperature and the water activity in the reaction were studied in detail in order to obtain the optimum conditions for Vitamin A palmitate synthesis. In a system of hexane, 100mg immobilized Candida sp. lipase was used in the presence of 1.2mmol vitamin A acetate and 3.6mmol palmitic acid. The yield of vitamin A palmitate reached 81% in 12h at 25℃. The immobilized Candida sp. lipase was prepared by adsorbing Cand/da sp. fermentation broth on pretreated textile and could be reused for at least six batches. 展开更多
关键词 vitamin A vitamin A palmitate lipase IMMOBILIZATION
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Studies on Production of Biodiesel by Esterification of Fatty Acids by a Lipase Preparation from Candida sp. 99-125 被引量:8
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作者 DENG Li(邓利) +5 位作者 NIE Kaili(聂开立) WANG Fang(王芳) TAN Tianwei(谭天伟) 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第4期529-534,共6页
A self-made lipase preparation from Candida sp. 99-125 was used for the production of biodiesel through enzymatic esterification of fatty acids. The crude lipase powder and fermentation broth were immobilized on a che... A self-made lipase preparation from Candida sp. 99-125 was used for the production of biodiesel through enzymatic esterification of fatty acids. The crude lipase powder and fermentation broth were immobilized on a cheap fiber cloth carrier. The conditions of lipase-catalyzed esterification between long-chain fatty acids and methanol in a solvent system were investigated in detail, including the temperature, pH value, substrate concentration, solvent, absorbent agent, enzyme dosage and purity, immobilization method, the mode of addition of substrate. The results show that reaction temperature, pH of lipase micro-environment, substrate concentration, enzyme dosage and purity affect the esterification strongly. Several new methods and enzymatic procedures for improving the enzymatic reaction involving the process cost are also discussed, such as fossil diesel fuel as reaction solvent, immobilization method, multi-step gradient addition of methanol. The esterification degree of 92.8% was obtained with oleic acid and methanol under the optimal reaction condition after 12.5 h reaction time. The half-life of the immobilized lipase preparation from crude free lipase powder for esterification was 15 days. 展开更多
关键词 BIODIESEL fatty acid short-chain alcohol ester immobilized lipase CATALYSIS ESTERIFICATION
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Cloning, overexpression, and characterization of a novel organic solvent-tolerant lipase from Paenibacillus pasadenensis CS0611 被引量:8
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作者 Jiaxin Gao Xiaoyang Ou +2 位作者 Pei Xu Minhua Zong Wenyong Lou 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第5期937-945,共9页
We found a novel lipase gene in the Paenibacillus pasadenensis CS0611 strain.The lipase gene sequence was cloned into the pET-28a expression vector to construct a recombinant lipase protein containing 6×His tags ... We found a novel lipase gene in the Paenibacillus pasadenensis CS0611 strain.The lipase gene sequence was cloned into the pET-28a expression vector to construct a recombinant lipase protein containing 6×His tags at the C-and N-termini,respectively.High-level expression of the lipase in E.coli BL21(DE3)was obtained upon induction with IPTG at 20°C.The recombinant lipase activity was approximately 1631-fold higher than the wild type.His-tagged recombinant lipase was purified rapidly and efficiently by using Ni-charged affinity chromatography with 63.5%recovery and a purification factor of 10.78.The purified lipase was stable in a broad range of temperatures and pH values,with the optimal temperature and pH being 50°C and 7.0,respectively.Its activity was stimulated to different degrees in the presence of metal ions such as Ca2+,Mg2+,and some non-ionic surfactants.In addition,the purified lipase was activated by a series of water-miscible organic solvents such as some short carbon chain alcohols and was highly tolerant to some water-immiscible organic solvents. 展开更多
关键词 lipase Paenibacillus pasadenensis CS0611 Expression CHARACTERIZATION Organic solvent tolerant
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Study on Immobilized Lipase Catalyzed Transesterification Reaction of Tung Oil 被引量:8
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作者 XU Gui-zhuan ZHANG Bai-liang LIU Sheng-yong YUE Jian-zhi 《Agricultural Sciences in China》 CAS CSCD 2006年第11期859-864,共6页
The transesterification reaction conditions of tung oil with methanol have been studied in this article, with immobilized lipase NOVO435 as catalyst. The response surface methodology was used to optimize the transeste... The transesterification reaction conditions of tung oil with methanol have been studied in this article, with immobilized lipase NOVO435 as catalyst. The response surface methodology was used to optimize the transesterification reaction of tung oil in a nonsolvent system. The optimal conditions were rotation rate 200 r/min, molar ratio of methanol to oil 2.2: l, reaction temperature 43℃, and the catalyst amount 14% (based on the weight of oil). After reacting for 18 h, 67.5% of the oil was converted to its corresponding methyl esters (the theoretical ester conversion was 73.3%). The lipase was washed by organic solvents after each reaction and was reused again. The esters conversion of tung oil was decreased by 6% after the lipase was reused for 120 h. The theoretical amount of methanol was added in two steps, 85% ester conversion was obtained after 36 h of reaction (theoretical ester conversion was 100%). The molar ratio of methanol to oil, the catalyst amount, the reaction temperature, and reaction time were all highly significant factors, and there was a relative significant interaction between every two factors. 展开更多
关键词 NONSOLVENT TRANSESTERIFICATION BIODIESEL lipase tung oil
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Synthesis of Wax Esters by Lipase-catalyzed Esterification with Immobilized Lipase from Candida sp. 99-125 被引量:8
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作者 邓利 王晓静 +4 位作者 聂开立 王芳 刘军峰 王璞 谭天伟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期978-982,共5页
Wax esters were synthesized in a solvent free system catalyzed by immobilized lipase from Candida sp. 99-125, with oleic acid and cetyl alcohol. The effects of substrate molar ratio, lipase dosage and water removal we... Wax esters were synthesized in a solvent free system catalyzed by immobilized lipase from Candida sp. 99-125, with oleic acid and cetyl alcohol. The effects of substrate molar ratio, lipase dosage and water removal were investigated in a 50 ml flask incubated in a thermostatic cultivation cabinet. The optimized conditions were: temperature 40 ℃, shaking at 170 r·min-1, acid/alcohol molar ratio 1:0.9, lipase dosage in 10% (by mass) of oleic acid, and open reaction for water removal. As a result, the conversion rate reached 98% for reaction of 8 h. The volume of reactor was scaled up to 1 L three-neck flask. The optimized parameters were: 200 r·min-1 agitation speed, 2.5% (by mass) lipase dosage, others were the same as the parameters described above. The conversion rate reached 95% for reaction of 24 h. The lipase retained 46% conversion rate after reuse for 6, 7 batches. The products were purified by removing remained cetyl alcohol and fatty acids with ethanol and saturated sodium carbonate so-lution, respectively. The purity of the wax ester, cetyl oleate, was 96%. The physical and chemical properties of cetyl oleate were tested and compared with those of jojoba oil. The results show that the product cetyl oleate has great potential to use as the substitute of natural jojoba oil. 展开更多
关键词 solvent free system Candida sp. 99-125 lipase wax ester
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Kinetics of the Esterification Reaction Catalyzed by Lipase in W/O Microemulsions of Alkyl Polyglucoside 被引量:8
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作者 JinLingCHAI ShouQingWANG +2 位作者 GanZuoLI QingXU YanHongGAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第6期699-702,共4页
A novel kinetic mechanism of esterification reaction of 1-hexanoic acid with 1-butanol, catalyzed by lipase, was studied in water-in-oil microemulsions. The microemulsions were formed by alkyl polyglucoside C10G1.54/1... A novel kinetic mechanism of esterification reaction of 1-hexanoic acid with 1-butanol, catalyzed by lipase, was studied in water-in-oil microemulsions. The microemulsions were formed by alkyl polyglucoside C10G1.54/1-butanol / cyclohexane/phosphate buffer solution. The result shows that when the ratio of mol concentration of 1-butanol to 1-hexanoic acid is about 3.0, the initial rate V0 get the maximum values. This phenomenon was explained by the modified fishlike phase diagrams. 展开更多
关键词 Alkyl polyglucoside W/O microemulsion lipase catalysis kinetics.
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Zwitterionic polymer-coated porous poly(vinyl acetate–divinyl benzene)microsphere: A new support for enhanced performance of immobilized lipase 被引量:4
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作者 Yifeng Li Chunyu Zhang Yan Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第1期242-248,共7页
Enzyme immobilization has attracted great attention for improving the performance of enzymes in industrial applications.This work was designed to create a new support for Candida rugosa lipase(CRL)immobilization.A por... Enzyme immobilization has attracted great attention for improving the performance of enzymes in industrial applications.This work was designed to create a new support for Candida rugosa lipase(CRL)immobilization.A porous poly(vinyl acetate–divinyl benzene)microsphere coated by a zwitterionic polymer,poly(maleic anhydride-alt-1-octadecene)and N,N-dimethylethylenediamine derivative,was developed for CRL immobilization via hydrophobic binding.The catalytic activity,reaction kinetics,stabilities and reusability of the immobilized CRL were investigated.It demonstrated the success of the zwitterionic polymer coating and subsequent CRL immobilization on the porous microsphere.The immobilized lipase(p2-MS-CRL)reached27.6 mg·g^-1 dry carrier and displayed a specific activity 1.5 times higher than free CRL.The increase of Vmax and decrease of Kmwere also observed,indicating the improvement of catalytic activity and enzyme-substrate affinity of the immobilized lipase.Besides,p2-MS-CRL exhibited significantly enhanced thermal stability and pH tolerance.The improved performance was considered due to the interfacial activation regulated by the hydrophobic interaction and stabilization effect arisen by the zwitterionic polymer coating.This study has thus proved the advantages of the zwitterionic polymer-coated porous carrier for lipase immobilization and its potential for further development in various enzyme immobilizations. 展开更多
关键词 BIOCATALYSIS lipase immobilization ZWITTERIONIC polymer HYDROPHOBIC binding Interfacial activation Stabilization
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Identification of five strains of antarctic bacteria producing low-temperature lipase 被引量:6
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作者 YANGXiuxia LINXuezheng +2 位作者 BIANJi SUNXiuqin HUANGXiaohang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第4期717-723,共7页
Five strains of antarctic bacteria producing extracellular low-temperature lipase are screened from seawater collectedby CTD during the Chinese 18th Antarctic Scientific Expedition. Their phylogenetic positions on the... Five strains of antarctic bacteria producing extracellular low-temperature lipase are screened from seawater collectedby CTD during the Chinese 18th Antarctic Scientific Expedition. Their phylogenetic positions on the basis ofamplification, comparison and analysis of almost complete 16S rDNA sequence are determined by neighbor-joininganalysis. Phylogenetic analysis indicates that all of these five strains belong to g-proteobacteria. The strains 11102 and 92 are classified as genus Pseudoalteromonas sp. and genus Psychrobacter sp. respectively. The strains 25101, 2221 and 1281 are classified as genus Moritella sp. 展开更多
关键词 antarctic bacteria low-temperature lipase 16S rDNA phylogenetic analysis
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