This study investigates the effects of capric acid-enriched medium-and long-chain structured lipids(SLs)microencapsulated synthesized by microbial lipase and grape seed oil(GSO)on obesity-related complications in mice...This study investigates the effects of capric acid-enriched medium-and long-chain structured lipids(SLs)microencapsulated synthesized by microbial lipase and grape seed oil(GSO)on obesity-related complications in mice subjected to a high-fat diet(HFD).Male C57BL/6J mice were assigned to various dietary groups:control diet(CD),high-fat diet(HFD),control diet with GSO(CDGO),high-fat diet with GSO(HFDGO),control diet with SLs(CDSL),and high-fat diet with SLs(HFDSL).Mice on the CD,CDGO,and CDSL diets exhibited reduced body weight gain compared to those on the HFD.Organ weights,including liver,heart,and testicles,were significantly higher in the HFD group compared to the CD,CDSL,and HFDSL groups,suggesting a potential protective effect of SLs.Dietary supplementation with SLs,particularly CDSL and HFDSL,enhanced glucose tolerance in HFD-fed mice.Insulin levels were markedly elevated in the HFD group;however,mice receiving HFDSL showed insulin levels comparable to those in the control groups(CD and HFDGO).The incorporation of capric acid into SLs resulted in lower leptin levels compared to GSO.Furthermore,a protective effect against hepatocellular microvesicular steatosis(MIS)and macro-vesicular steatosis(MAS)was observed in mice fed SLs-rich diets,especially CDSL and HFDSL.Total steatosis(TS)was significantly lower in mice on the CDGO and CDSL diets compared to those on the control diet(CD),indicating a notable protective effect of SLs treatment.In conclusion,capric acidrich SLs derived from GSO demonstrate potential as functional oils,offering protection against obesity and associated metabolic disorders,evidenced by measurements such as 23.30 U/L of alanine aminotransferase(ALT),105.00 UI/L of alkaline phosphatase(ALP),93.54 mg/dL of triglycerides(TAGs),and 183.54 mg/dL of cholesterol.展开更多
The demand for natural and healthy products has driven research into new value-added products derived from avocado(Persea Americana var.Hass)oil.For example,the exploration of the production of structured lipids(SL),w...The demand for natural and healthy products has driven research into new value-added products derived from avocado(Persea Americana var.Hass)oil.For example,the exploration of the production of structured lipids(SL),which are modified triacylglycerides with enhanced nutritional and functional properties.Enzymatic engineering of structured lipids using immobilized lipases allows for greater economy and stability under reaction conditions.In this study,medium-and long-chain structured lipids were produced from avocado oil caprylic acid by enzymatic acidolysis.Lipase from Thermomyces lanuginosus was immobilized on corn cob powder.Efficient incorporation of caprylic acid(C8:0)into avocado oil was achieved with a maximum of 31.11%at sn-1 or sn-3 positions.However,incorporation did not occur simultaneously into triacylglycerides,and lipase reusability of up to 4 cycles.In the hepatocarcinoma cell line Hep-G2,the structured and hydrolyzed lipids inhibited cell viability,suggesting their potential for future studies related to the maintenance of liver health.展开更多
Sacha inchi oil(SIO)and red palm oil(RPO)have potential nutritious and functional applications.Their combination may yield lipid-based products that contain high amounts of polyunsaturated fatty acids(PUFAs),carotenoi...Sacha inchi oil(SIO)and red palm oil(RPO)have potential nutritious and functional applications.Their combination may yield lipid-based products that contain high amounts of polyunsaturated fatty acids(PUFAs),carotenoids,tocopherols,and phytosterols.This study explored the effect of enzymatic interesterification(EIE)catalyzed by the sn-1,3-specific Lipozyme^(R)TL IM on three different ratios of RPO:SIO mixtures:75:25,50:50,and 25:75(w/w).At higher RPO concentrations,more higher-melting triacylglycerols(TAGs)were incorporated into the mixture,particularly C46 and C48 TAGs.Conversely,increasing the SIO concentration incorporated more lower-melting TAGs dominated by PUFAs such asα-linolenic and linoleic acids.Upon EIE,relative TAG abundance experienced changes where trisaturated(S3)and triunsaturated(U3)TAGs decreased,whereas disaturated(S2U)and diunsaturated(SU2)TAGs increased.Melting behavior and fat crystal structure as resolved by differential scanning calorimetry and X-ray scattering analysis,respectively,also revealed notable differences between blends.The blend with the highest RPO content produced higher-melting peaks,thus presenting a potential use in plastic fat-related applications.In contrast,a blend with higher SIO ratios may be used in the preparation of margarine or other lipid products.Further studies and optimization are warranted to focus on the applications of blends in one particular use.展开更多
Medium-and long-chain triglycerides(MLCT)are a novel type of functional lipids that exhibit higher bioavailability when long-chain polyunsaturated fatty acids are esterified at the sn-2 position of the glycerol backbo...Medium-and long-chain triglycerides(MLCT)are a novel type of functional lipids that exhibit higher bioavailability when long-chain polyunsaturated fatty acids are esterified at the sn-2 position of the glycerol backbone.Enzyme-catalyzed synthesis of MLCT offers significant advantages,including environmental benig-nity,exceptional catalytic efficiency,and negligible by-product formation.Nevertheless,the inherent limitations of free enzymes in terms of recyclability and industrial implementation,remain a challenge.In this study,the hydrophobicity of the amino resin support LX-1000HAA(HAA)was modified via grafting with dodecenyl suc-cinic anhydride(DDSA).The lipase RM was then immobilized onto the HAA-DDSA carrier via physical adsorption.The activity of the resulting immobilized lipase HAA-DDSA-RM was 1.74 times that of Lipozyme RM C and 2.13 times that of HAA-RM.Analysis of the adsorption kinetics and isotherms for lipase adsorption onto HAA-DDSA revealed that the adsorption behavior conformed to both the pseudo-second-order kinetic model and the Freundlich isotherm model.HAA-DDSA-RM was then employed in the preparation of MLCT in the reaction system comprising algal oil and capric acid.The DHA content at the sn-2 position reached 73.40%in the final product.Moreover,HAA-DDSA-RM demonstrated outstanding thermal stability,good storage stability,and su-perior recyclability,with 96%of its initial activity after 10 successive operational cycles.This study may provide a new approach for environmentally sustainable production of functional lipids by developing a robust immo-bilized lipase system.展开更多
Medium-and long-chain structured lipids(MLSLs)rich in docosahexaenoic acid(DHA)and eicosapentaenoic acid(EPA)were synthesized by acidolysis of fish oil(Omax 1812,a mixture of sardine and anchovy oils)with caprylic aci...Medium-and long-chain structured lipids(MLSLs)rich in docosahexaenoic acid(DHA)and eicosapentaenoic acid(EPA)were synthesized by acidolysis of fish oil(Omax 1812,a mixture of sardine and anchovy oils)with caprylic acid(CA)using a lipase bio-imprinted with fatty acids as a catalyst.A bio-imprinted lipase for the acidolysis reaction was first prepared under optimal conditions,and its activity was 1.43 times higher than that of the non-bioimprinted.The bio-imprinted lipase was used as a catalyst to produce such MLSLs,and the reaction conditions were optimized.Under the optimal conditions,equilibrium was achieved in 8 h,and the total and the sn-1,3 CA contents in the obtained product were 28.72%and 42.26%.Additionally,the total and the sn-2 DHA contents were 14.23%and 21.10%,respectively,and the total and the sn-2 EPA contents were 16.43%and 10.14%,respectively.These obtained MLSLs,rich in sn-1,3 CA,and sn-2 DHA,EPA can deliver significant health benefits.展开更多
UPU structured lipids refer to a class of functional lipids that are connected to palmitic acid(PA,16:0)at the sn-2 position and unsaturated fatty acid(UFA)at the sn-1,3 positions.UPU structured lipids are ingredients...UPU structured lipids refer to a class of functional lipids that are connected to palmitic acid(PA,16:0)at the sn-2 position and unsaturated fatty acid(UFA)at the sn-1,3 positions.UPU structured lipids are ingredients of infant formula and are beneficial to fat absorption in infants and young children.At present,the research on UPU structured lipids is mainly focused on species identification,physiological functions and preparation methods.In this paper,we summarize the natural oils and fats enriched with PA at the sn-2 position,which can be used as a substrate for the enzymatic preparation of UPU.In addition,the emerging fermentation method for the preparation of UPU structured lipids was briefly reviewed aiming to provide scientific reference for the in-depth investigation of UPU structured lipids.展开更多
The normal development and maintenance of central neural functions are highly correlated with the amount of docosahexaenoic acid(DHA;ω-3 fatty acid)accumulated in the brain.DHA incorporated at the sn-2 position of li...The normal development and maintenance of central neural functions are highly correlated with the amount of docosahexaenoic acid(DHA;ω-3 fatty acid)accumulated in the brain.DHA incorporated at the sn-2 position of lipids is well absorbed by intestinal mucosa and utilized efficiently in vivo.However,modern consumers have a reduced direct intake of DHA and increased intake of saturated fats or ω-6 fatty acid oils,resulting in behavioral and neurophysiological deficits.To provide an understanding of the integrated beneficial effects of DHA on the human brain,this review introduces the positional difference(sn-2 and sn-1,3 positions)of DHA on a glycerol skeleton in natural fats and oils,and further discusses the possible functional mechanism regarding DHA supplementation and the gut-brain axis.The multiple bidirectional routes in this axis offer a novel insight into the interaction between DHA supplementation,the gut microbiota,and brain health.To achieve high sn-2 DHA in diets,it is suggested that sn-2 DHA lipids be enzymatically produced in more efficient and economical ways by improving the specific activities of lipases and optimizing the purification procedures.These types of diets will benefit individuals with strong needs for sn-2 ω-3 lipids such as infants,children,and pregnant and lactating women.展开更多
The medium chain fatty acids(MCFAs)including capric acid(CA),lauric acid(LA)and their monoglyceride improve metabolic health and diet-induced obesity in high-fat diet(HFD)-fed mice.However,their unpleasant smell and r...The medium chain fatty acids(MCFAs)including capric acid(CA),lauric acid(LA)and their monoglyceride improve metabolic health and diet-induced obesity in high-fat diet(HFD)-fed mice.However,their unpleasant smell and rapid digestibility limit their applications in food industry.In this research,CA-LA structural lipids(S_(DL)/S_(LD))were synthesized through direct esterification.S_(DL) released more CA and glyceryl monocaprate(GMD)during in vitro digestion,while S_(LD) produced more LA and glycerol monolaurate(GML).After digestion,S_(LD) showed stronger inhibitory effect on Staphylococcus aureus compared to S_(DL),S_(DL) had more antibacterial activity against Escherichia coli and Candida albicans compared to S_(LD).Both of them significantly reduced hepatic lipid accumulation,improved adipocytes hypertrophy,and ameliorated hyperlipidemia with decreased circulating triglyceride(TG)and total cholesterol(T-CHO)levels.The insulin sensitivity was also improved by S_(DL)/S_(LD) treatment,especially for increased serum glucagon-like peptide-1(GLP-1)concentration.Moreover,S_(DL)/S_(LD) also modulated systemic inflammation,resulting in decreased serum levels of proinflammatory cytokines,lipopolysaccharide(LPS),indicators of macrophage infiltration in HFD-fed mice.In particular,S_(LD) significantly increased beneficial gut bacteria(Dubosiella,Akkermansia)and alleviated HFD-induced metabolic dysregulation.These findings substantiated that S_(LD) served as a novel nutritional intervention for mitigating obesity and its associated metabolic comorbidities.展开更多
Recently, the effect of ligand receptor interaction on the membrane structure of liposomes has been studied extensively. However, little is known about how it exists on biological membranes. In this paper, the effect ...Recently, the effect of ligand receptor interaction on the membrane structure of liposomes has been studied extensively. However, little is known about how it exists on biological membranes. In this paper, the effect of Con-canavalin A (ConA) receptor interaction on the structure of cell membranes was studied by Circular Dichroism (CD) and 3lP Nuclear Magnetic Resonance (NMR).CD results of both the purified macrophage membranes and human erythrocyte ghosts (EG) showed that the conformation of membrane proteins changed after ConA bind ing.For further research, 31P-NMR was used to detect the organization of phospholipid molecules on macrophage mem branes. After ConA binding, the tendency to form non bi-layer structure increased with the amount of ConA. The changes of 31P-NMR spectra of living macrophages might be partly due to the above stated reason too.In addition, ConA-receptor interaction also induced similar results of 31P-NMR spectra in EG. In contrast, wheat germ agglutinin (WGA ), another kind of lectin, rarely showed the same influence.展开更多
Triacylglycerols are the main constituents of natural fats and oils and contribute directly to their texture and flavor. The DSC （differential scanning calorimetry） of fats and oils is usually performed in order to ...Triacylglycerols are the main constituents of natural fats and oils and contribute directly to their texture and flavor. The DSC （differential scanning calorimetry） of fats and oils is usually performed in order to characterize their melting and crystallization characteristics. The effect of the chemically catalyzed interesterification of two vegetable oils, i.e. palm stearin and linseed oil, on the thermal behavior of the product is studied. The objective of this study is to analyze the impact of the transesterification reaction conditions and of the initial amounts of oils on the thermal behavior of the product. This work shows that both cooling and heating DSC thermograms undergo significant changes as the result of the mixture of linseed oil and palm stearin and of their transesterification.展开更多
Background The nutritional support is one of the important therapeutic strategies for the elderly patients with severe sepsis,but there is controversial in choosing a parenteral nutrition formulation.This study was de...Background The nutritional support is one of the important therapeutic strategies for the elderly patients with severe sepsis,but there is controversial in choosing a parenteral nutrition formulation.This study was designed to compare the therapeutic effects of structured lipid emulsion,physically mixed medium,and long-chain fat emulsion in the treatment of severe sepsis in elderly patients.Methods A total number of 64 elder patients with severe sepsis were enrolled in the study.After a week of enteral nutritional support,the patients were randomly divided into research （structured lipid emulsion as parenteral alimentation） and control groups （physically mixed medium and long-chain fat emulsion as parenteral alimentation）.The alterations of plasma albumin,lipid metabolism,and blood glucose level were recorded after parenteral alimentation and were compared between the two groups.Results The plasma levels of albumin,prealbumin,cholesterol,and triglyceride were decreased in all the patients after one week of enteral nutritional support treatment （t=7.78,P=0.000; t=10.21,P=0.000; t=7.99,P=0.000; and t=10.99,P=0.000）.Further parenteral alimentation with different lipid emulsions had significant effects on the serum prealbumin and albumin （t=3.316,P=0.002; t=3.200,P=0.002）,whilst had no effects on the blood glucose and triglyceride level （t=7.78,P=0.000; t=4.228,P=0.000）.In addition,the two groups had a significantly different Apache Ⅱ score,ventilator time,and hospital stay time （t=-2.213,P=0.031;t=2.317,P=0.024; t=2.514,P=0.015）.Conclusions The structured lipid emulsion was safe as parenteral nutrition for elderly patients with severe sepsis.It was demonstrated to be superior to the physically mixed medium and long-chain fat emulsion with respect to the protein synthesis and prognosis.展开更多
Medium-and long-chain triglycerides(MLCT)have been widely concerned.In this study,lauric acid(La)was incorporated into flaxseed(Linum usitatissimum L.)oil(FO,aLna-riched)by lipase-catalyzed acidolysis.The synthesis ef...Medium-and long-chain triglycerides(MLCT)have been widely concerned.In this study,lauric acid(La)was incorporated into flaxseed(Linum usitatissimum L.)oil(FO,aLna-riched)by lipase-catalyzed acidolysis.The synthesis efficiency of four immobilized lipases(Lipozyme RM IM,TL IM,AOAB8 and Novozym 435)was compared,while Lipozyme AOAB8 reaction for 2 h was the best scheme.Further,the optimal conditions for synthesizing structural lipids(aLSLs,rich in aLna and La)were obtained by response surface methodology:the reaction temperature was 44.6℃,substrate molar ratio was 12(La/FO),and enzyme loading was 9.11%.After purification by molecular distillation,the triglycerides(TAGs)of aLSLs contained 75.35% of TAGs withα-linolenic acid(aLna),40.82%of MLCTs with La,and 26.75%(65.53% of the total MLCTs)of TAGs with both aLna and La(ɑ-MLCT).Meanwhile,the content of La and aLna in aLSLs were 22.38%and 39.78%,respectively.The chemical structure and microstructure of aLSLs were similar to FO.In addition,the thermo-oxidative decomposition behavior of aLSLs was significantly improved compared with physical mixture oil.This improvement might be related to the insertion of La and the structure of TAG.In all,this study firstly developed a novel thermo-oxidatively stable MLCT with high levels of aLna and La.展开更多
Butyric acid and lauric acid are short chain and medium chain fatty acids,respectively.Their anti-inflammatory and lipid metabolism regulating functions are reported,while their structural lipid functional activity st...Butyric acid and lauric acid are short chain and medium chain fatty acids,respectively.Their anti-inflammatory and lipid metabolism regulating functions are reported,while their structural lipid functional activity still needs to be verified.In this study,obese mice induced by high-fat diet(HFD)were used to investigate the effects of butyric-lauric acid structural lipid(SBL)on inflammation and small intestinal microbes.In vivo,although SBL did not significantly reduce body weight(P>0.05),it might have a positive effect on mouse liver health.Compared to the corresponding physical mixture(MBL),SBL treatment could better downregulate hepatic TNF-α,IL-1β and IL-6 expression and stimulate IL-10 expression.Similarly,compared with the HF group,the liver IL-1β and TNF-α levels in the LSBL treatment group decreased by 15.2% and 22.9%,respectively(P<0.05).In addition,HSBL treatment increased the content of IL-10 in the liver of obese mice(increased by 26.8%,P<0.05).Moreover,SBL more significantly upregulated Bifidobacterium abundance and inhibited the high-fat diet-induced increase in Faecalibaculum abundance.In all,SBL ameliorated HFD-induced liver inflammation and these improvements are closely associated with its positive effects on small intestinal microbiota.This study aimed to provide support and new perspectives for the development and functional exploration of short-and medium-chain fatty acid structural lipids.展开更多
The objective of this study was to produce structured lipids(SLs)enriched in docosahexaenoic acid(DHA)by enzymatic interesterification of a medium-chain triacylglycerol(MCT)oil and docosahexaenoic acid single cell oil...The objective of this study was to produce structured lipids(SLs)enriched in docosahexaenoic acid(DHA)by enzymatic interesterification of a medium-chain triacylglycerol(MCT)oil and docosahexaenoic acid single cell oil(DHASCO),using immobilized lipases from Thermomyces lanuginosus(TL)and Candida rugosa(CR).The enzymes were screened for their effectiveness,and optimal conditions were employed to evaluate their ability to incorporate DHA or medium-chain fatty acids(MCFAs)into the triacylglycerol backbone.Fatty acid composition,regiospecific distribution,and oxidative stability were assessed in both the original and structured lipids.Structured lipids were prepared under ultrasonic-assisted enzymatic interesterification,and their oxidative stability was evaluated using conjugated dienes(CD)and 2-thiobarbituric acid reactive substances(TBARS)assays.The results indicated that after 1 h of incubation,DHA content in the resultant product was reduced to 31.22%and 32.66%with TL and CR lipases,respectively.For MCFAs,long chain saturated fatty acids(LC-SFAs)and long chain polyunsaturated fatty acids(LC-PUFAs),the amounts were 35.29%,15.91%and 15.06%(TL:Thermomyces lanuginosus),and 25.92%,20.04%and 17.83%(CR:Candida rugosa),respectively.In DHASCO,DHA was predominantly esterified to the sn-2 position,while MCFAs occupied mainly the sn-1 and sn-3 positions.In MCT,MCFAs were esterified to all positions,but as the chain length increased from C8 to C16,saturated FAs decreased in the sn-1 and sn-2 positions but not in the sn-3 position.In novel structured lipids so produced,DHA was mainly attached to the sn-2 position,with C8:0 to C16:0 esterified to sn-1,3 positions.Enzymatically modified oil generally had higher CD and TBARS values compared to their unmodified counterparts.These findings demonstrate potential for rational design of structured lipids,offering a venue to tailor their composition and enhanced potential nutritional value.展开更多
基金supported by the Ministry of Science,Tech-nology,and Innovation of Colombia(Minciencias),Postsecondary Ed-ucation Agency of the Mayor’s Office of Medellin(Colombia)2021-2 and the Banco de la Republica Foundation(Colombia),with grant number 4.639.
文摘This study investigates the effects of capric acid-enriched medium-and long-chain structured lipids(SLs)microencapsulated synthesized by microbial lipase and grape seed oil(GSO)on obesity-related complications in mice subjected to a high-fat diet(HFD).Male C57BL/6J mice were assigned to various dietary groups:control diet(CD),high-fat diet(HFD),control diet with GSO(CDGO),high-fat diet with GSO(HFDGO),control diet with SLs(CDSL),and high-fat diet with SLs(HFDSL).Mice on the CD,CDGO,and CDSL diets exhibited reduced body weight gain compared to those on the HFD.Organ weights,including liver,heart,and testicles,were significantly higher in the HFD group compared to the CD,CDSL,and HFDSL groups,suggesting a potential protective effect of SLs.Dietary supplementation with SLs,particularly CDSL and HFDSL,enhanced glucose tolerance in HFD-fed mice.Insulin levels were markedly elevated in the HFD group;however,mice receiving HFDSL showed insulin levels comparable to those in the control groups(CD and HFDGO).The incorporation of capric acid into SLs resulted in lower leptin levels compared to GSO.Furthermore,a protective effect against hepatocellular microvesicular steatosis(MIS)and macro-vesicular steatosis(MAS)was observed in mice fed SLs-rich diets,especially CDSL and HFDSL.Total steatosis(TS)was significantly lower in mice on the CDGO and CDSL diets compared to those on the control diet(CD),indicating a notable protective effect of SLs treatment.In conclusion,capric acidrich SLs derived from GSO demonstrate potential as functional oils,offering protection against obesity and associated metabolic disorders,evidenced by measurements such as 23.30 U/L of alanine aminotransferase(ALT),105.00 UI/L of alkaline phosphatase(ALP),93.54 mg/dL of triglycerides(TAGs),and 183.54 mg/dL of cholesterol.
基金funded by the General Royalties System(SGR)in the 7th call of the Ministry of Science,Technology and Innovation-MinCiencias-Colombiathe University of Antioquia for the financial support through CODI project2022-52912。
文摘The demand for natural and healthy products has driven research into new value-added products derived from avocado(Persea Americana var.Hass)oil.For example,the exploration of the production of structured lipids(SL),which are modified triacylglycerides with enhanced nutritional and functional properties.Enzymatic engineering of structured lipids using immobilized lipases allows for greater economy and stability under reaction conditions.In this study,medium-and long-chain structured lipids were produced from avocado oil caprylic acid by enzymatic acidolysis.Lipase from Thermomyces lanuginosus was immobilized on corn cob powder.Efficient incorporation of caprylic acid(C8:0)into avocado oil was achieved with a maximum of 31.11%at sn-1 or sn-3 positions.However,incorporation did not occur simultaneously into triacylglycerides,and lipase reusability of up to 4 cycles.In the hepatocarcinoma cell line Hep-G2,the structured and hydrolyzed lipids inhibited cell viability,suggesting their potential for future studies related to the maintenance of liver health.
文摘Sacha inchi oil(SIO)and red palm oil(RPO)have potential nutritious and functional applications.Their combination may yield lipid-based products that contain high amounts of polyunsaturated fatty acids(PUFAs),carotenoids,tocopherols,and phytosterols.This study explored the effect of enzymatic interesterification(EIE)catalyzed by the sn-1,3-specific Lipozyme^(R)TL IM on three different ratios of RPO:SIO mixtures:75:25,50:50,and 25:75(w/w).At higher RPO concentrations,more higher-melting triacylglycerols(TAGs)were incorporated into the mixture,particularly C46 and C48 TAGs.Conversely,increasing the SIO concentration incorporated more lower-melting TAGs dominated by PUFAs such asα-linolenic and linoleic acids.Upon EIE,relative TAG abundance experienced changes where trisaturated(S3)and triunsaturated(U3)TAGs decreased,whereas disaturated(S2U)and diunsaturated(SU2)TAGs increased.Melting behavior and fat crystal structure as resolved by differential scanning calorimetry and X-ray scattering analysis,respectively,also revealed notable differences between blends.The blend with the highest RPO content produced higher-melting peaks,thus presenting a potential use in plastic fat-related applications.In contrast,a blend with higher SIO ratios may be used in the preparation of margarine or other lipid products.Further studies and optimization are warranted to focus on the applications of blends in one particular use.
基金supported by the National Key Research and Development Program of China(2023YFF1103502).
文摘Medium-and long-chain triglycerides(MLCT)are a novel type of functional lipids that exhibit higher bioavailability when long-chain polyunsaturated fatty acids are esterified at the sn-2 position of the glycerol backbone.Enzyme-catalyzed synthesis of MLCT offers significant advantages,including environmental benig-nity,exceptional catalytic efficiency,and negligible by-product formation.Nevertheless,the inherent limitations of free enzymes in terms of recyclability and industrial implementation,remain a challenge.In this study,the hydrophobicity of the amino resin support LX-1000HAA(HAA)was modified via grafting with dodecenyl suc-cinic anhydride(DDSA).The lipase RM was then immobilized onto the HAA-DDSA carrier via physical adsorption.The activity of the resulting immobilized lipase HAA-DDSA-RM was 1.74 times that of Lipozyme RM C and 2.13 times that of HAA-RM.Analysis of the adsorption kinetics and isotherms for lipase adsorption onto HAA-DDSA revealed that the adsorption behavior conformed to both the pseudo-second-order kinetic model and the Freundlich isotherm model.HAA-DDSA-RM was then employed in the preparation of MLCT in the reaction system comprising algal oil and capric acid.The DHA content at the sn-2 position reached 73.40%in the final product.Moreover,HAA-DDSA-RM demonstrated outstanding thermal stability,good storage stability,and su-perior recyclability,with 96%of its initial activity after 10 successive operational cycles.This study may provide a new approach for environmentally sustainable production of functional lipids by developing a robust immo-bilized lipase system.
基金supported by the National Natural Science Foundation of China(31601433).
文摘Medium-and long-chain structured lipids(MLSLs)rich in docosahexaenoic acid(DHA)and eicosapentaenoic acid(EPA)were synthesized by acidolysis of fish oil(Omax 1812,a mixture of sardine and anchovy oils)with caprylic acid(CA)using a lipase bio-imprinted with fatty acids as a catalyst.A bio-imprinted lipase for the acidolysis reaction was first prepared under optimal conditions,and its activity was 1.43 times higher than that of the non-bioimprinted.The bio-imprinted lipase was used as a catalyst to produce such MLSLs,and the reaction conditions were optimized.Under the optimal conditions,equilibrium was achieved in 8 h,and the total and the sn-1,3 CA contents in the obtained product were 28.72%and 42.26%.Additionally,the total and the sn-2 DHA contents were 14.23%and 21.10%,respectively,and the total and the sn-2 EPA contents were 16.43%and 10.14%,respectively.These obtained MLSLs,rich in sn-1,3 CA,and sn-2 DHA,EPA can deliver significant health benefits.
基金Key Research Projects of Colleges and Universities of Henan Province(23A550002)Zhengzhou R&D Special Fund(22ZZRDZX25)Doctoral Scientific Research Start-up Foundation from Henan University of Technology(2021BS015).
文摘UPU structured lipids refer to a class of functional lipids that are connected to palmitic acid(PA,16:0)at the sn-2 position and unsaturated fatty acid(UFA)at the sn-1,3 positions.UPU structured lipids are ingredients of infant formula and are beneficial to fat absorption in infants and young children.At present,the research on UPU structured lipids is mainly focused on species identification,physiological functions and preparation methods.In this paper,we summarize the natural oils and fats enriched with PA at the sn-2 position,which can be used as a substrate for the enzymatic preparation of UPU.In addition,the emerging fermentation method for the preparation of UPU structured lipids was briefly reviewed aiming to provide scientific reference for the in-depth investigation of UPU structured lipids.
基金supported by the Chinese Scholarship Council(201706790068)the Free Exploration Founded Project of the State Key Laboratory of Food Science and Technology at Jiangnan University(SKLF-ZZA-201705)supported in part by Food Science Research,University of Georgia.
文摘The normal development and maintenance of central neural functions are highly correlated with the amount of docosahexaenoic acid(DHA;ω-3 fatty acid)accumulated in the brain.DHA incorporated at the sn-2 position of lipids is well absorbed by intestinal mucosa and utilized efficiently in vivo.However,modern consumers have a reduced direct intake of DHA and increased intake of saturated fats or ω-6 fatty acid oils,resulting in behavioral and neurophysiological deficits.To provide an understanding of the integrated beneficial effects of DHA on the human brain,this review introduces the positional difference(sn-2 and sn-1,3 positions)of DHA on a glycerol skeleton in natural fats and oils,and further discusses the possible functional mechanism regarding DHA supplementation and the gut-brain axis.The multiple bidirectional routes in this axis offer a novel insight into the interaction between DHA supplementation,the gut microbiota,and brain health.To achieve high sn-2 DHA in diets,it is suggested that sn-2 DHA lipids be enzymatically produced in more efficient and economical ways by improving the specific activities of lipases and optimizing the purification procedures.These types of diets will benefit individuals with strong needs for sn-2 ω-3 lipids such as infants,children,and pregnant and lactating women.
基金supported by the National Natural Science Foundation of China(No 32372316 and 32172214)National Key Research and Development Program of China(2023YFF1104003).
文摘The medium chain fatty acids(MCFAs)including capric acid(CA),lauric acid(LA)and their monoglyceride improve metabolic health and diet-induced obesity in high-fat diet(HFD)-fed mice.However,their unpleasant smell and rapid digestibility limit their applications in food industry.In this research,CA-LA structural lipids(S_(DL)/S_(LD))were synthesized through direct esterification.S_(DL) released more CA and glyceryl monocaprate(GMD)during in vitro digestion,while S_(LD) produced more LA and glycerol monolaurate(GML).After digestion,S_(LD) showed stronger inhibitory effect on Staphylococcus aureus compared to S_(DL),S_(DL) had more antibacterial activity against Escherichia coli and Candida albicans compared to S_(LD).Both of them significantly reduced hepatic lipid accumulation,improved adipocytes hypertrophy,and ameliorated hyperlipidemia with decreased circulating triglyceride(TG)and total cholesterol(T-CHO)levels.The insulin sensitivity was also improved by S_(DL)/S_(LD) treatment,especially for increased serum glucagon-like peptide-1(GLP-1)concentration.Moreover,S_(DL)/S_(LD) also modulated systemic inflammation,resulting in decreased serum levels of proinflammatory cytokines,lipopolysaccharide(LPS),indicators of macrophage infiltration in HFD-fed mice.In particular,S_(LD) significantly increased beneficial gut bacteria(Dubosiella,Akkermansia)and alleviated HFD-induced metabolic dysregulation.These findings substantiated that S_(LD) served as a novel nutritional intervention for mitigating obesity and its associated metabolic comorbidities.
文摘Recently, the effect of ligand receptor interaction on the membrane structure of liposomes has been studied extensively. However, little is known about how it exists on biological membranes. In this paper, the effect of Con-canavalin A (ConA) receptor interaction on the structure of cell membranes was studied by Circular Dichroism (CD) and 3lP Nuclear Magnetic Resonance (NMR).CD results of both the purified macrophage membranes and human erythrocyte ghosts (EG) showed that the conformation of membrane proteins changed after ConA bind ing.For further research, 31P-NMR was used to detect the organization of phospholipid molecules on macrophage mem branes. After ConA binding, the tendency to form non bi-layer structure increased with the amount of ConA. The changes of 31P-NMR spectra of living macrophages might be partly due to the above stated reason too.In addition, ConA-receptor interaction also induced similar results of 31P-NMR spectra in EG. In contrast, wheat germ agglutinin (WGA ), another kind of lectin, rarely showed the same influence.
文摘Triacylglycerols are the main constituents of natural fats and oils and contribute directly to their texture and flavor. The DSC （differential scanning calorimetry） of fats and oils is usually performed in order to characterize their melting and crystallization characteristics. The effect of the chemically catalyzed interesterification of two vegetable oils, i.e. palm stearin and linseed oil, on the thermal behavior of the product is studied. The objective of this study is to analyze the impact of the transesterification reaction conditions and of the initial amounts of oils on the thermal behavior of the product. This work shows that both cooling and heating DSC thermograms undergo significant changes as the result of the mixture of linseed oil and palm stearin and of their transesterification.
文摘Background The nutritional support is one of the important therapeutic strategies for the elderly patients with severe sepsis,but there is controversial in choosing a parenteral nutrition formulation.This study was designed to compare the therapeutic effects of structured lipid emulsion,physically mixed medium,and long-chain fat emulsion in the treatment of severe sepsis in elderly patients.Methods A total number of 64 elder patients with severe sepsis were enrolled in the study.After a week of enteral nutritional support,the patients were randomly divided into research （structured lipid emulsion as parenteral alimentation） and control groups （physically mixed medium and long-chain fat emulsion as parenteral alimentation）.The alterations of plasma albumin,lipid metabolism,and blood glucose level were recorded after parenteral alimentation and were compared between the two groups.Results The plasma levels of albumin,prealbumin,cholesterol,and triglyceride were decreased in all the patients after one week of enteral nutritional support treatment （t=7.78,P=0.000; t=10.21,P=0.000; t=7.99,P=0.000; and t=10.99,P=0.000）.Further parenteral alimentation with different lipid emulsions had significant effects on the serum prealbumin and albumin （t=3.316,P=0.002; t=3.200,P=0.002）,whilst had no effects on the blood glucose and triglyceride level （t=7.78,P=0.000; t=4.228,P=0.000）.In addition,the two groups had a significantly different Apache Ⅱ score,ventilator time,and hospital stay time （t=-2.213,P=0.031;t=2.317,P=0.024; t=2.514,P=0.015）.Conclusions The structured lipid emulsion was safe as parenteral nutrition for elderly patients with severe sepsis.It was demonstrated to be superior to the physically mixed medium and long-chain fat emulsion with respect to the protein synthesis and prognosis.
基金The authors gratefully acknowledge the funding support of Key Project of Science and Technology Innovation 2025 program(2019B10060)the National Natural Science Foundation of China(32072224).
文摘Medium-and long-chain triglycerides(MLCT)have been widely concerned.In this study,lauric acid(La)was incorporated into flaxseed(Linum usitatissimum L.)oil(FO,aLna-riched)by lipase-catalyzed acidolysis.The synthesis efficiency of four immobilized lipases(Lipozyme RM IM,TL IM,AOAB8 and Novozym 435)was compared,while Lipozyme AOAB8 reaction for 2 h was the best scheme.Further,the optimal conditions for synthesizing structural lipids(aLSLs,rich in aLna and La)were obtained by response surface methodology:the reaction temperature was 44.6℃,substrate molar ratio was 12(La/FO),and enzyme loading was 9.11%.After purification by molecular distillation,the triglycerides(TAGs)of aLSLs contained 75.35% of TAGs withα-linolenic acid(aLna),40.82%of MLCTs with La,and 26.75%(65.53% of the total MLCTs)of TAGs with both aLna and La(ɑ-MLCT).Meanwhile,the content of La and aLna in aLSLs were 22.38%and 39.78%,respectively.The chemical structure and microstructure of aLSLs were similar to FO.In addition,the thermo-oxidative decomposition behavior of aLSLs was significantly improved compared with physical mixture oil.This improvement might be related to the insertion of La and the structure of TAG.In all,this study firstly developed a novel thermo-oxidatively stable MLCT with high levels of aLna and La.
基金supported by Natural Science Foundation of Zhejiang Province(LQ21C200007)the National Natural Science Foundation of China(32172214,32001693).
文摘Butyric acid and lauric acid are short chain and medium chain fatty acids,respectively.Their anti-inflammatory and lipid metabolism regulating functions are reported,while their structural lipid functional activity still needs to be verified.In this study,obese mice induced by high-fat diet(HFD)were used to investigate the effects of butyric-lauric acid structural lipid(SBL)on inflammation and small intestinal microbes.In vivo,although SBL did not significantly reduce body weight(P>0.05),it might have a positive effect on mouse liver health.Compared to the corresponding physical mixture(MBL),SBL treatment could better downregulate hepatic TNF-α,IL-1β and IL-6 expression and stimulate IL-10 expression.Similarly,compared with the HF group,the liver IL-1β and TNF-α levels in the LSBL treatment group decreased by 15.2% and 22.9%,respectively(P<0.05).In addition,HSBL treatment increased the content of IL-10 in the liver of obese mice(increased by 26.8%,P<0.05).Moreover,SBL more significantly upregulated Bifidobacterium abundance and inhibited the high-fat diet-induced increase in Faecalibaculum abundance.In all,SBL ameliorated HFD-induced liver inflammation and these improvements are closely associated with its positive effects on small intestinal microbiota.This study aimed to provide support and new perspectives for the development and functional exploration of short-and medium-chain fatty acid structural lipids.
基金the Natural Sciences and Engineering Research Council(NSERC)of Canada for a Discovery Grant(RGPN to FS and the Vietnam International Education Development(VIED)for a scholarship NVL.
文摘The objective of this study was to produce structured lipids(SLs)enriched in docosahexaenoic acid(DHA)by enzymatic interesterification of a medium-chain triacylglycerol(MCT)oil and docosahexaenoic acid single cell oil(DHASCO),using immobilized lipases from Thermomyces lanuginosus(TL)and Candida rugosa(CR).The enzymes were screened for their effectiveness,and optimal conditions were employed to evaluate their ability to incorporate DHA or medium-chain fatty acids(MCFAs)into the triacylglycerol backbone.Fatty acid composition,regiospecific distribution,and oxidative stability were assessed in both the original and structured lipids.Structured lipids were prepared under ultrasonic-assisted enzymatic interesterification,and their oxidative stability was evaluated using conjugated dienes(CD)and 2-thiobarbituric acid reactive substances(TBARS)assays.The results indicated that after 1 h of incubation,DHA content in the resultant product was reduced to 31.22%and 32.66%with TL and CR lipases,respectively.For MCFAs,long chain saturated fatty acids(LC-SFAs)and long chain polyunsaturated fatty acids(LC-PUFAs),the amounts were 35.29%,15.91%and 15.06%(TL:Thermomyces lanuginosus),and 25.92%,20.04%and 17.83%(CR:Candida rugosa),respectively.In DHASCO,DHA was predominantly esterified to the sn-2 position,while MCFAs occupied mainly the sn-1 and sn-3 positions.In MCT,MCFAs were esterified to all positions,but as the chain length increased from C8 to C16,saturated FAs decreased in the sn-1 and sn-2 positions but not in the sn-3 position.In novel structured lipids so produced,DHA was mainly attached to the sn-2 position,with C8:0 to C16:0 esterified to sn-1,3 positions.Enzymatically modified oil generally had higher CD and TBARS values compared to their unmodified counterparts.These findings demonstrate potential for rational design of structured lipids,offering a venue to tailor their composition and enhanced potential nutritional value.
