Lysosomal acid lipase-deficiency(LAL-D)is a rare and systemic condition,secondary to lipase A gene mutations,responsible for lysosomal accumulation of cholesteryl esters and triglycerides in many tissues.It is a very ...Lysosomal acid lipase-deficiency(LAL-D)is a rare and systemic condition,secondary to lipase A gene mutations,responsible for lysosomal accumulation of cholesteryl esters and triglycerides in many tissues.It is a very heterogeneous disease in terms of the age of onset,severity,and the type of clinical and radiological manifestations.Dyslipidemia,hepatomegaly,and hepatosteatosis with increased levels of transaminases are the most common features.In association with liver dysfunction and evolution to cirrhosis,there is an increased risk of premature atherosclerosis and cardiovascular disorders,secondary to a generalized alteration of lipid profile and lipoprotein dysfunction associated with LAL-D.Therefore,we provide an update on the frequently under-recognized LAL-D,focusing on the late-onset form:Cholesteryl ester storage disease.展开更多
The preparation of immobilized enzyme with excellent performance is one of the difficulties that restrict the application of enzyme catalysis technology.Here,Candida rugosa lipase(CRL)was firstly adsorbed on the surfa...The preparation of immobilized enzyme with excellent performance is one of the difficulties that restrict the application of enzyme catalysis technology.Here,Candida rugosa lipase(CRL)was firstly adsorbed on the surface of magnetic zeolitic imidazolate framework-8(ZIF-8)nanospheres,which was further encapsulated with a mesoporous SiO_(2)nano-membrane formed by tetraethyl orthosilicate(TEOS)polycondensation.Consequently,lipase could be firmly immobilized on carrier surface by physical binding rather than chemical binding,which did not damage the active conformation of enzyme.There were mesopores on the silica nano-membrane,which could improve the accessibility of enzyme and its apparent catalytic activity.Moreover,silica membrane encapsulation could also improve the stability of enzyme,suggesting an effective enzyme immobilization strategy.It showed that TEOS amount and the encapsulation time had significant effects on the thickness of silica membrane and the enzyme activity.The analysis in enzyme activity and protein secondary structure showed that lipase encapsulated in silica membrane retained the active conformation to the greatest extent.Compared with the adsorbed lipase,the encapsulated lipase increased its thermostability by 3 times and resistance to chemical denaturants by 7 times.The relative enzyme activity remained around 80%after 8 repetitions,while the adsorbed lipase only remained at7.3%.展开更多
Background:The prediction of postoperative pancreatic fistula(POPF)is important.This study aimed to investigate the role of postoperative serum lipase level in predicting POPF.Methods:Data from 234 consecutive patient...Background:The prediction of postoperative pancreatic fistula(POPF)is important.This study aimed to investigate the role of postoperative serum lipase level in predicting POPF.Methods:Data from 234 consecutive patients who underwent pancreaticoduodenectomy(PD)were collected.The predictive values of serum amylase and serum lipase during postoperative days(PODs)1 to 3 for POPF were compared.Subgroup analyses were performed to determine the prognostic value of different levels and durations of elevated serum lipase.Results:Fifty-six patients developed POPF.The POPF group exhibited increased levels of serum amylase and lipase from PODs 1 to 3(all P<0.001).Compared with serum amylase,serum lipase has greater predictive value for POPF.Specifically,serum lipase had the highest area under the receiver operating characteristic curve(AUC)at POD 1(0.791).Body mass index>24 kg/m2[odds ratio(OR)=2.431,95%confidence interval(CI):1.094–5.404,P=0.029],soft pancreatic texture(OR=3.189,95%CI:1.263–8.056,P=0.014),serum lipase>60 U/L at POD 1(OR=5.135,95%CI:1.257–20.982,P=0.023),and C-reactive protein>167 mg/dL at POD 3(OR=3.607,95%CI:1.431–9.090,P=0.007)were identified as independent risk factors for POPF.Patients with serum lipase≤60 U/L at POD 1(n=104)exhibited lower rates of POPF(3.8%vs.40.0%,P<0.001)and severe complications(Clavien-Dindo≥IIIa)(4.8%vs.25.4%,P<0.001)than those with serum lipase>60 U/L at POD 1.Moreover,no additional elevation or duration of serum lipase offered any further prognostic value.Conclusions:Postoperative serum lipase outperformed serum amylase in the prediction of POPF,and patients with normal serum lipase level at POD 1 had favorable outcomes.A sustained increase in the serum lipase level offers no additional prognostic value.展开更多
Extreme environmental conditions such as temperature fluctuations,drought,and pathogen attacks can significantly impact plant growth,development,and productivity.Plants have evolved intricate enzymatic systems to miti...Extreme environmental conditions such as temperature fluctuations,drought,and pathogen attacks can significantly impact plant growth,development,and productivity.Plants have evolved intricate enzymatic systems to mitigate these stresses,among which GDSL esterase/lipase proteins (GELPs)-key members of the serine esterase/lipase superfamily-play important roles (Akoh et al.,2004).Characterized by a conserved GDSL motif and four essential amino acids (serine,glycine,asparagine,and histidine),GELPs exhibit versatile catalytic functions in lipid metabolism,cell wall modification,and stress responses (Ursache et al.,2021;Shen et al.,2022).展开更多
Currently,the worldwide prevalence of morbid obesity has increased.1 The National Health and Nutrition Examination Survey from the Centers for Disease Control and Prevention revealed that the prevalence of obesity in ...Currently,the worldwide prevalence of morbid obesity has increased.1 The National Health and Nutrition Examination Survey from the Centers for Disease Control and Prevention revealed that the prevalence of obesity in the adult population between 20 and 74 years old had more than doubled from 13.3%to 31.1%from 1960 to 2002.2 Metabolic and bariatric surgery(MBS)is now suggested for patients with a body mass index(BMI)of more than 35 kg/m2,comorbidities or no comorbidities.Furthermore,MBS should be offered to people with metabolic disease and a BMI of 30e34.9 kg/m2 who have failed to gain a meaningful amount of weight or have failed to keep it off with non-surgical management.However,the BMI cutoff points should be modified for the Asian population.展开更多
Male reproductive development is necessary for the alternation of the life cycle in angiosperms.Due to functional redundancy of genes in the allohexaploid genome of common wheat,there are only two loci of recessive nu...Male reproductive development is necessary for the alternation of the life cycle in angiosperms.Due to functional redundancy of genes in the allohexaploid genome of common wheat,there are only two loci of recessive nuclear genic male sterility(GMS)mutations reported in wheat.Here,we report a new wheat recessive GMS gene,Ta Ms6,which encodes a GDSL esterase/lipase protein(GELP).Ta Ms6 is predominantly expressed in the anther during meiosis and the unicellular microspore stage,especially in meiotic cells(MCs),dyad cells,tapetum,and middle layer.The loss of Ta Ms6 function leads to male sterility,likely due to the downregulation of some pollen development-related genes and changes in lipid composition during meiosis.The ms6 mutant and Ms6 gene can potentially be utilized for developing commercialscale hybrid wheat breeding systems.We also systematically analyzed the GELP gene family in wheat,providing a comprehensive understanding of the Ta GELP family and offering valuable references for indepth genetic studies.Additionally,we discovered the nonallelic noncomplementation of two malesterile mutants,which presents an interesting and promising research direction.展开更多
[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
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
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
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
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
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
Pomegranate leaf(PGL)has a definite role in regulating lipid metabolism.However,pharmacokinetic results show the main active ingredient,ellagic acid,in PGL has lower oral bioavailability,suggesting that the lipid-lowe...Pomegranate leaf(PGL)has a definite role in regulating lipid metabolism.However,pharmacokinetic results show the main active ingredient,ellagic acid,in PGL has lower oral bioavailability,suggesting that the lipid-lowering effect of PGL may act through inhibiting lipid absorption in the small intestine.Our results demonstrated that pomegranate leaf and its main active ingredients(i.e.,ellagic acid,gallic acid,pyrogallic acid and tannic acid)were capable of inhibiting pancreatic lipase activity in vitro.In computational molecular docking,the four ingredients had good affinity for pancreatic lipase.Acute lipid overload experiments showed that a large dosage of PGL significantly reduced serum total cholesterol(TG)and triglycerides(TC)levels in addition to inhibiting intestinal lipase activity,which demonstrated that PGL could inhibit lipase activity and reduce the absorption of lipids.We also found that PGL could reverse the reduced tight-junction protein expression due to intestinal lipid overload,promote Occludin and Claudin4 expression in the small intestine,and enhance the intestinal mucosal barrier.In conclusion,we demonstrated that PGL can inhibit lipid absorption and reduce blood TG and TC by targeting pancreatic lipase,promoting tight-junction protein expression and thereby preventing intestinal mucosa damage from an overload of lipids in the intestine.展开更多
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
Pancreatic lipase(PL), a crucial enzyme in the digestive system of mammals, has been proven as a therapeutic target to prevent and treat obesity. The purpose of this study is to evaluate and characterize the PL inhibi...Pancreatic lipase(PL), a crucial enzyme in the digestive system of mammals, has been proven as a therapeutic target to prevent and treat obesity. The purpose of this study is to evaluate and characterize the PL inhibition activities of the major constituents from Fructus Psoraleae(FP), one of the most frequently used Chinese herbs with lipid-lowering activity. To this end, a total of eleven major constituents isolated from Fructus Psoraleae have been obtained and their inhibition potentials against PL have been assayed by a fluorescence-based assay. Among all tested compounds, isobavachalcone, bavachalcone and corylifol A displayed strong inhibition on PL(IC50 < 10 μmol·L-1). Inhibition kinetic analyses demonstrated that isobavachalcone, bavachalcone and corylifol A acted as mixed inhibitors against PL-mediated 4-methylumbelliferyl oleate(4-MUO) hydrolysis, with the Ki values of 1.61, 3.77 and 10.16μmol·L-1, respectively. Furthermore, docking simulations indicated that two chalcones(isobavachalcone and bavachalcone) could interact with the key residues located in the catalytic cavity of PL via hydrogen binding and hydrophobic interactions. Collectively, these finding provided solid evidence to support that Fructus Psoraleae contained bioactive compounds with lipid-lowering effects via targeting PL, and also suggested that the chalcones in Fructus Psoraleae could be used as ideal leading compounds to develop novel PL inhibitors.展开更多
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
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
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
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
文摘Lysosomal acid lipase-deficiency(LAL-D)is a rare and systemic condition,secondary to lipase A gene mutations,responsible for lysosomal accumulation of cholesteryl esters and triglycerides in many tissues.It is a very heterogeneous disease in terms of the age of onset,severity,and the type of clinical and radiological manifestations.Dyslipidemia,hepatomegaly,and hepatosteatosis with increased levels of transaminases are the most common features.In association with liver dysfunction and evolution to cirrhosis,there is an increased risk of premature atherosclerosis and cardiovascular disorders,secondary to a generalized alteration of lipid profile and lipoprotein dysfunction associated with LAL-D.Therefore,we provide an update on the frequently under-recognized LAL-D,focusing on the late-onset form:Cholesteryl ester storage disease.
基金the financial supports from the National Natural Science Foundation of China(Nos.22378093,21878065)Natural Science Foundation of Hebei Province,China(No.E2022201100)+2 种基金the Science and Technology Support Plan of Baoding City(No.2241ZF111)the Medical Science Foundation of Hebei University(No.2021A09)the Foundation of Affiliated Hospital of Hebei University(No.2021Z003)。
文摘The preparation of immobilized enzyme with excellent performance is one of the difficulties that restrict the application of enzyme catalysis technology.Here,Candida rugosa lipase(CRL)was firstly adsorbed on the surface of magnetic zeolitic imidazolate framework-8(ZIF-8)nanospheres,which was further encapsulated with a mesoporous SiO_(2)nano-membrane formed by tetraethyl orthosilicate(TEOS)polycondensation.Consequently,lipase could be firmly immobilized on carrier surface by physical binding rather than chemical binding,which did not damage the active conformation of enzyme.There were mesopores on the silica nano-membrane,which could improve the accessibility of enzyme and its apparent catalytic activity.Moreover,silica membrane encapsulation could also improve the stability of enzyme,suggesting an effective enzyme immobilization strategy.It showed that TEOS amount and the encapsulation time had significant effects on the thickness of silica membrane and the enzyme activity.The analysis in enzyme activity and protein secondary structure showed that lipase encapsulated in silica membrane retained the active conformation to the greatest extent.Compared with the adsorbed lipase,the encapsulated lipase increased its thermostability by 3 times and resistance to chemical denaturants by 7 times.The relative enzyme activity remained around 80%after 8 repetitions,while the adsorbed lipase only remained at7.3%.
基金supported by grants from the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2019-I2M-5–056)the National Natural Science Foundation of China(81930119,82090050,and 82090053)。
文摘Background:The prediction of postoperative pancreatic fistula(POPF)is important.This study aimed to investigate the role of postoperative serum lipase level in predicting POPF.Methods:Data from 234 consecutive patients who underwent pancreaticoduodenectomy(PD)were collected.The predictive values of serum amylase and serum lipase during postoperative days(PODs)1 to 3 for POPF were compared.Subgroup analyses were performed to determine the prognostic value of different levels and durations of elevated serum lipase.Results:Fifty-six patients developed POPF.The POPF group exhibited increased levels of serum amylase and lipase from PODs 1 to 3(all P<0.001).Compared with serum amylase,serum lipase has greater predictive value for POPF.Specifically,serum lipase had the highest area under the receiver operating characteristic curve(AUC)at POD 1(0.791).Body mass index>24 kg/m2[odds ratio(OR)=2.431,95%confidence interval(CI):1.094–5.404,P=0.029],soft pancreatic texture(OR=3.189,95%CI:1.263–8.056,P=0.014),serum lipase>60 U/L at POD 1(OR=5.135,95%CI:1.257–20.982,P=0.023),and C-reactive protein>167 mg/dL at POD 3(OR=3.607,95%CI:1.431–9.090,P=0.007)were identified as independent risk factors for POPF.Patients with serum lipase≤60 U/L at POD 1(n=104)exhibited lower rates of POPF(3.8%vs.40.0%,P<0.001)and severe complications(Clavien-Dindo≥IIIa)(4.8%vs.25.4%,P<0.001)than those with serum lipase>60 U/L at POD 1.Moreover,no additional elevation or duration of serum lipase offered any further prognostic value.Conclusions:Postoperative serum lipase outperformed serum amylase in the prediction of POPF,and patients with normal serum lipase level at POD 1 had favorable outcomes.A sustained increase in the serum lipase level offers no additional prognostic value.
基金supported by the National Natural Science Foundation of China(Grant No.32402580)the Science and Technology Program of Guangdong Province(Grant No.2023A0505090005)Modern Seed Industry Innovation Capability Enhancement Project of Guangdong Academy of Agricultural Sciences.
文摘Extreme environmental conditions such as temperature fluctuations,drought,and pathogen attacks can significantly impact plant growth,development,and productivity.Plants have evolved intricate enzymatic systems to mitigate these stresses,among which GDSL esterase/lipase proteins (GELPs)-key members of the serine esterase/lipase superfamily-play important roles (Akoh et al.,2004).Characterized by a conserved GDSL motif and four essential amino acids (serine,glycine,asparagine,and histidine),GELPs exhibit versatile catalytic functions in lipid metabolism,cell wall modification,and stress responses (Ursache et al.,2021;Shen et al.,2022).
文摘Currently,the worldwide prevalence of morbid obesity has increased.1 The National Health and Nutrition Examination Survey from the Centers for Disease Control and Prevention revealed that the prevalence of obesity in the adult population between 20 and 74 years old had more than doubled from 13.3%to 31.1%from 1960 to 2002.2 Metabolic and bariatric surgery(MBS)is now suggested for patients with a body mass index(BMI)of more than 35 kg/m2,comorbidities or no comorbidities.Furthermore,MBS should be offered to people with metabolic disease and a BMI of 30e34.9 kg/m2 who have failed to gain a meaningful amount of weight or have failed to keep it off with non-surgical management.However,the BMI cutoff points should be modified for the Asian population.
基金supported by Shandong Provincial Natural Science Foundation(ZR2022ZD22,ZR2021ZD30,SYS202206)Shandong Agricultural University Dezhou(Qihe)Wheat Research Institute。
文摘Male reproductive development is necessary for the alternation of the life cycle in angiosperms.Due to functional redundancy of genes in the allohexaploid genome of common wheat,there are only two loci of recessive nuclear genic male sterility(GMS)mutations reported in wheat.Here,we report a new wheat recessive GMS gene,Ta Ms6,which encodes a GDSL esterase/lipase protein(GELP).Ta Ms6 is predominantly expressed in the anther during meiosis and the unicellular microspore stage,especially in meiotic cells(MCs),dyad cells,tapetum,and middle layer.The loss of Ta Ms6 function leads to male sterility,likely due to the downregulation of some pollen development-related genes and changes in lipid composition during meiosis.The ms6 mutant and Ms6 gene can potentially be utilized for developing commercialscale hybrid wheat breeding systems.We also systematically analyzed the GELP gene family in wheat,providing a comprehensive understanding of the Ta GELP family and offering valuable references for indepth genetic studies.Additionally,we discovered the nonallelic noncomplementation of two malesterile mutants,which presents an interesting and promising research direction.
基金Supported by Subproject of"Development and Utilization of Plant Resources under Special Environment"from the National Project"863"(2007AA021401)Corps Doctoral Foundation of"Study on Transgenic Breeding Technology"(2006JC07)~~
文摘[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.
基金This work was supported by the Grant from Tianjin Municipal Natural Science Foundations (No. 033607311).
文摘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.
基金supported by the Major Program of the Hebei Province Commission of Science and Technology during the 11 th Five-Year-Plan period,China(06220106D)
文摘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.
文摘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.
文摘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.
基金Supported by the National Natural Science Foundation of China (No.20325622), Key Technology R&D Programme (No.2001BA708B03-08) and 863 Hi-Technology Research and Development Program of China (No. 2002AA514030).
文摘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.
基金supported by the National S&T Major Special Project for New Drug R&D Program of China(2011ZX09101-002-11)the Special Foundation for Laboratory of Tsinghua University(LF20082377)the National Natural Science Foundation of China(Nos.81374006 and 30801523)
文摘Pomegranate leaf(PGL)has a definite role in regulating lipid metabolism.However,pharmacokinetic results show the main active ingredient,ellagic acid,in PGL has lower oral bioavailability,suggesting that the lipid-lowering effect of PGL may act through inhibiting lipid absorption in the small intestine.Our results demonstrated that pomegranate leaf and its main active ingredients(i.e.,ellagic acid,gallic acid,pyrogallic acid and tannic acid)were capable of inhibiting pancreatic lipase activity in vitro.In computational molecular docking,the four ingredients had good affinity for pancreatic lipase.Acute lipid overload experiments showed that a large dosage of PGL significantly reduced serum total cholesterol(TG)and triglycerides(TC)levels in addition to inhibiting intestinal lipase activity,which demonstrated that PGL could inhibit lipase activity and reduce the absorption of lipids.We also found that PGL could reverse the reduced tight-junction protein expression due to intestinal lipid overload,promote Occludin and Claudin4 expression in the small intestine,and enhance the intestinal mucosal barrier.In conclusion,we demonstrated that PGL can inhibit lipid absorption and reduce blood TG and TC by targeting pancreatic lipase,promoting tight-junction protein expression and thereby preventing intestinal mucosa damage from an overload of lipids in the intestine.
文摘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.
基金the National Key Research and Development Program of China (Nos.2017YFC1700200,2017YFC1702000)NSF of China (Nos.81922070, 81973286, 81973393, 81773687)+4 种基金Natural Science Foundation of Liaoning Province (No.20180530025)Program of Shanghai Academic/Technology Research Leader (No. 18XD1403600)Shuguang Program (No. 18SG40) supported by Shanghai Education Development Foundation and Shanghai Municipal Education CommissionInnovative Entrepreneurship Program of High-level Talents in Dalian (No. 2017RQ121)Undergraduate Training Program for Innovation and Entrepreneurship from Shanghai University of Traditional Chinese Medicine (No. 2017101419803010904)。
文摘Pancreatic lipase(PL), a crucial enzyme in the digestive system of mammals, has been proven as a therapeutic target to prevent and treat obesity. The purpose of this study is to evaluate and characterize the PL inhibition activities of the major constituents from Fructus Psoraleae(FP), one of the most frequently used Chinese herbs with lipid-lowering activity. To this end, a total of eleven major constituents isolated from Fructus Psoraleae have been obtained and their inhibition potentials against PL have been assayed by a fluorescence-based assay. Among all tested compounds, isobavachalcone, bavachalcone and corylifol A displayed strong inhibition on PL(IC50 < 10 μmol·L-1). Inhibition kinetic analyses demonstrated that isobavachalcone, bavachalcone and corylifol A acted as mixed inhibitors against PL-mediated 4-methylumbelliferyl oleate(4-MUO) hydrolysis, with the Ki values of 1.61, 3.77 and 10.16μmol·L-1, respectively. Furthermore, docking simulations indicated that two chalcones(isobavachalcone and bavachalcone) could interact with the key residues located in the catalytic cavity of PL via hydrogen binding and hydrophobic interactions. Collectively, these finding provided solid evidence to support that Fructus Psoraleae contained bioactive compounds with lipid-lowering effects via targeting PL, and also suggested that the chalcones in Fructus Psoraleae could be used as ideal leading compounds to develop novel PL inhibitors.
基金Supported by the National Natural Science Foundation of China (No. 20176020) and 863 Hi-Technology Research and Deve-lopment Program of China (No. 2002AA514030)
文摘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.
文摘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.
基金Supported by the National＇High Technology Research and Development Program of China （2009AA02Z207）, the National Natural Science Foundation of China （20876012） and the Hi-Tech Research and Development Program of China （2009AA03Z232, 2010AA101601）.
文摘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.
文摘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.
