Dry-fermented sausages are a good source of bioactive peptides,whose stability against gastrointestinal(GI)digestion determines their bioaccessibility.This study focused on evaluating the effect of peptide extracts fr...Dry-fermented sausages are a good source of bioactive peptides,whose stability against gastrointestinal(GI)digestion determines their bioaccessibility.This study focused on evaluating the effect of peptide extracts from sausages fermented with Staphylococcus simulans QB7 during in vitro simulated GI digestion,including peptide profiles and antioxidant and anti-inflammatory activities.Peptides present in sausages were degraded during digestion,with molecular weight reduced from>12 kDa to<1.5 kDa.Besides,the content of amino acids increased from 381.15 to 527.07 mg/g,especially tyrosine being found only after GI digestion.The anti-inflammatory activities were increased after GI digestion,however,the changes in antioxidant activities were the opposite.A total number of 255,252 and 386 peptide sequences were identified in undigested,peptic-digested and GI-digested samples,respectively.PeptideRanker,BIOPEP-UWM and admetSAR were used to further predict the functional properties and intestinal absorption of the identified peptide sequences from GI digestion.Finally,18 peptides were discovered to possess either antioxidant or anti-inflammatory capacities.展开更多
The study evaluated the stability of an oligopeptide(Lys-Arg-Gln-Lys-Tyr-Asp,KRQKYD)and its transport mechanism by simulating gastrointestinal digestion and a model of human intestinal Caco-2 monolayer cells in vitro....The study evaluated the stability of an oligopeptide(Lys-Arg-Gln-Lys-Tyr-Asp,KRQKYD)and its transport mechanism by simulating gastrointestinal digestion and a model of human intestinal Caco-2 monolayer cells in vitro.In this study,the effects of environmental factors(temperature,pH and NaCl concentration)and simulated gastrointestinal digestion on the stability of KRQKYD were evaluated by indicators of the levels of alanine transaminase(ALT),aspartate transaminase(AST)and malondialdehyde(MDA)in an alcoholinduced hepatocyte injury model.The results showed that KRQKYD still maintained satisfactory hepatocyteprotective activity after treatment with different temperatures(20-80℃),pH(3.0-9.0),NaCl concentration(1%-7%)and simulated gastrointestinal digestion,which indicated that KRQKYD showed good stability to environmental factors and simulated gastrointestinal digestion.Furthermore,the intact KRQKYD could be absorbed in a model of Caco-2 monolayer cells with a P_(app)value of(9.70±0.53)×10^(-7)cm/s.Pretreatment with an energy inhibitor(sodium azide),a competitive peptide transporter inhibitor(Gly-Pro)and a transcytosis inhibitor wortmannin did not decrease the level of transepithelial KRQKYD transport,indicating that the transport mechanism of KRQKYD was not associated with energy dependent,vector mediated and endocytosis.The tight junction disruptor cytochalasin D significantly increased the level of transepithelial KRQKYD transport(P<0.05),suggesting that intact KRQKYD was absorbed by paracellular transport.展开更多
Peptides from Alcalase-hydrolyzed soybean protein hydrolysate(SPH)may hold the potential as natural antioxidants.In addition,the effect of human gastrointestinal(GI)tract on peptide bioavailability needs to be explore...Peptides from Alcalase-hydrolyzed soybean protein hydrolysate(SPH)may hold the potential as natural antioxidants.In addition,the effect of human gastrointestinal(GI)tract on peptide bioavailability needs to be explored.In this study,the impact of simulated GI digestion and transepithelial transport on various antioxidant properties of SPH were investigated.SPH displayed DPPH radical scavenging(IC50=4.22 mg/m L),ABTS·+radical scavenging(IC50=2.93 mg/m L),reducing power and metal ion-chelating activities(IC50=0.67 mg/m L).Furthermore,SPH significantly(P<0.05)inhibited the generation of intracellular reactive oxygen species(ROS)in Caco-2 cells.After simulated GI digestion,the antioxidant properties of SPH were enhanced,except for a decrease in ABTS·+radical scavenging activity.After transepithelial transport,the permeates maintained partial antioxidant activity and the LC-MS/MS data further identified the absorbed soybean peptides.These results suggest that SPH contains the antioxidant peptides that are potentially bioavailable and can be regarded as a promising source of functional food ingredients.展开更多
OBJECTIVE Epimedium is rich in a variety of beneficial active ingredients,and has been widely used in the ethnopharmacological practices,however,its biotransformation in gastrointestinal digestions remain unclear.This...OBJECTIVE Epimedium is rich in a variety of beneficial active ingredients,and has been widely used in the ethnopharmacological practices,however,its biotransformation in gastrointestinal digestions remain unclear.This study aimed to investigate the dynamic changes of components and biological activity of Epimedium in the in vitro simulated digestion and subsequent human faecal fermentation.METHODS The models of in vitro simulated saliva,gastric and intestinal digestion,as well as colonic fermentation were constructed to simulate the digestion process of Epimedium.The dynamic changes of components of Epimedium during the simulated digestions in vitro and subsequent human faecal fermentation were investigated by UPLC-MS,HPLC-DAD combined with principal component analysis(PCA)and multi-ingredient quantitative analysis.RESULTS A variety of metabolites with high contents were produced after 0.5 h of intestinal digestion and colonic fermentation 0.5 h.Application of PCA to HPLC data showed the obvious separation of colonic fermentation 0.5 h stage samples from other colonic fermentation stages samples(24,48 and 72 h).Additionally,non-digestion and saliva digestion stage samples clustered together,and there was obvious separation between intestinal digestion samples and gastric digestion samples.The contents of epimedium C,icariin and baohuside I all increased significantly after intestinal digestion[58.70±7.08,47.15±5.68 and(12.78±0.55)mg·g^(-1)]compared with gastric digestion[29.00±5.65,17.40±4.55 and(2.77±0.19)mg·g^(-1)].There were significant differences between sample after 0.5 h of colonic fermentation[64.22±9.32,51.26±6.33 and(16.68±3.19)mg·g^(-1)]and other time points(24,48 and 72 h)in components and the contents of active ingredient,and the content of these components all decreased with the fermentation time.The ability of scavenging ABTS free radicals[IC50=(0.29±0.02)g·L^(-1)]increased significantly compared with gastric digestion[(1.57±0.02)g·L^(-1)],and after 0.5 h of colonic fermentation,the ability also increased significantly.CONCLUSION Gastrointestinal digestion had a significant impact on the contents of active components in Epimedium,and the metabolism of these components mainly occurred in the colon.The intestinal digestion and colonic fermentation significantly improved the anti-ABTS activity of epimedium.展开更多
The main protease(M^(pro))is essential for the replication of SARS-COV-2 and therefore represents a promising anti-viral target.In this study,we screened M^(pro)inhibitory peptides from Ulva prolifera protein on in-si...The main protease(M^(pro))is essential for the replication of SARS-COV-2 and therefore represents a promising anti-viral target.In this study,we screened M^(pro)inhibitory peptides from Ulva prolifera protein on in-silico proteolysis.Cytotoxicity analysis using the online toxic prediction tool ToxinPred revealed that all the peptides were non-cytotoxic.The hexapeptide(SSGFID)exhibited high M^(pro)inhibitory activity in molecular docking and its IC_(50)value was 139.40±0.82μmol/L in vitro according to fluorescence resonance energy transfer assay(FRET).Quantitative real-time(qRT-)PCR results show that SSGFID could stimulate the expression of mitosis-related factors,including nuclear factor-κB,cyclin D1,and cyclin-dependent kinase 4,to promote the proliferation of mice splenocytes.Stability study revealed that SSGFID showed resistance against pepsin and trypsin but lost D(Asp)after pretreatment at121℃ for 15 min.Besides,SSGFID was mainly transported through the Caco-2 cell monolayer by the peptide transporter PepT1 and passive-mediated transport during the transport study.Unfortunately,the peptide was also degraded by Caco-2 intracellular enzymes,and the transfer rate of intact peptide was4.2%.Furthermore,Lineweaver–Burk plots demonstrated that SSGFID possessed a mixed inhibitory characteristic with M^(pro).Our study indicated the potential of Ulva prolifera as antiviral and immuneenhancing functional food ingredients and nutraceuticals.展开更多
Oysters(Crassostrea gigas)have a wide range of functionality due to their nutritional and bioactive components. However, the bioactive peptides of oyster proteins are rarely reported, particularly their antidiabetes e...Oysters(Crassostrea gigas)have a wide range of functionality due to their nutritional and bioactive components. However, the bioactive peptides of oyster proteins are rarely reported, particularly their antidiabetes effects and antioxidants. Oyster proteins were extracted from fresh oysters using phosphatebuffered saline and simulated gastrointestinal digestion was performed. The degree of hydrolysis(DH), structural characterization, molecular weight(Mw)distribution, free amino acid, anti-diabetic activity, and antioxidant activity were studied during in vitro simulated gastrointestinal digestion. The results showed that the α-glucosidase inhibitory activity, α-amylase inhibitory activity, DPPH radical scavenging activity, and ABTS radical scavenging activity of the oyster protein gastrointestinal digest were increased(P < 0.05)from 0 to 33.96%, from 9.17% to 44.22%, from 9.01 μg trolox/mg protein to 18.48 μg trolox/mg protein, and from 21.44 μg trolox/mg protein to 56.21 μg trolox/mg protein, respectively. Additionally, the DH, β-turn structure, fluorescence intensity, free amino acid, and short peptide content(Mw < 1 000 Da)increased in the simulated gastrointestinal digestion. These results indicate that the digestive hydrolysates obtained from oyster proteins could be used as natural anti-diabetic and antioxidant agents.展开更多
This study aimed to isolate and characterize the structures of glycoproteins from peas and determine their hypoglycemic activity.The crude pea glycoproteins(PGP)were extracted by hot water and purified by diethylamino...This study aimed to isolate and characterize the structures of glycoproteins from peas and determine their hypoglycemic activity.The crude pea glycoproteins(PGP)were extracted by hot water and purified by diethylaminoethyl(DEAE)-Sepharose chromatography and Sephadex G-100 size-exclusion chromatography in sequence.Then three main fractions were obtained,namely PGP1,PGP2 and PGP3,with molecular weights of 897615,846740 and 1194692 Da,respectively.The physical and chemical properties of the three fractions were evaluated and compared by Fourier transform infrared spectroscopy(FT-IR),nuclear magnetic resonance(NMR),scanning electron microscope(SEM),high performance liquid chromatography(HPLC)and other analytical techniques.The fraction PGP2 with the highest hypoglycemic activity,was screened using the Caco-2 monolayer cell model.It can inhibit the uptake of glucose in the small intestine,as well as the activities of maltase and sucrase.After simulated gastrointestinal digestion,PGP2 signifi cantly enhanced the inhibitory effect of α-glucosidase,and slightly reduced the inhibitory ability ofα-amylase.In summary,PGP2 possessed strong hypoglycemic activity after digestion.These results indicated that PGP2 has the potential to be developed into a functional food or natural medicine for the treatment of type 2 diabetes mellitus.展开更多
This study aimed to in vitro evaluate the impact of common gastrointestinal(GI)alterations appearing with aging on protein digestibility,and functional related properties,in four different meats(chicken,turkey,pork an...This study aimed to in vitro evaluate the impact of common gastrointestinal(GI)alterations appearing with aging on protein digestibility,and functional related properties,in four different meats(chicken,turkey,pork and beef).Thus,three elderly digestion models were stated as long as altered GI conditions affected at oral(E1),oral and gastric(E2)and oral,gastric and intestinal stages(E3).Healthy adult GI conditions were also mimicked as standard control model(C).A notable trichloroacetic acid(TCA)soluble protein and the free amino acids(FAA)release reduction(p<0.05)were found under intestinal suboptimal conditions(E3),being more accused in beef than in other meats.Thus,chicken intake would be more advisable,than other meats,in terms of protein digestibility;while beef would provide a greater net supply of FAA under E3 model conditions.Gastric altered conditions,seem to favor protein solubility.Finally,while gastric and intestinal suboptimal conditions diminish the angiotensin converting enzyme(ACE)inhibition of meat digesta,their antioxidant activity was only negatively affected by intestinal altered conditions.展开更多
Immunoglobulin Y(Ig Y)is an effective orally administered antibody used to protect against various intestinal pathogens,but which cannot tolerate the acidic gastric environment.In this study,Ig Y was microencapsulated...Immunoglobulin Y(Ig Y)is an effective orally administered antibody used to protect against various intestinal pathogens,but which cannot tolerate the acidic gastric environment.In this study,Ig Y was microencapsulated by alginate(ALG)and coated with chitooligosaccharide(COS).A response surface methodology was used to optimize the formulation,and a simulated gastrointestinal(GI)digestion(SGID)system to evaluate the controlled release of microencapsulated Ig Y.The microcapsule formulation was optimized as an ALG concentration of 1.56%(15.6 g/L),COS level of 0.61%(6.1 g/L),and Ig Y/ALG ratio of 62.44%(mass ratio).The microcapsules prepared following this formulation had an encapsulation efficiency of 65.19%,a loading capacity of 33.75%,and an average particle size of 588.75μm.Under this optimum formulation,the coating of COS provided a less porous and more continuous microstructure by filling the cracks on the surface,and thus the GI release rate of encapsulated Ig Y was significantly reduced.The release of encapsulated Ig Y during simulated gastric and intestinal digestion well fitted the zero-order and first-order kinetics functions,respectively.The microcapsule also allowed the Ig Y to retain 84.37%immune-activity after 4 h simulated GI digestion,significantly higher than that for unprotected Ig Y(5.33%).This approach could provide an efficient way to preserve Ig Y and improve its performance in the GI tract.展开更多
Polyphenol-rich purple rice has been shown to exhibit a wide range of health properties including antioxidant activity.This study aimed to determine the impact that gastrointestinal digestion of purple rice had on its...Polyphenol-rich purple rice has been shown to exhibit a wide range of health properties including antioxidant activity.This study aimed to determine the impact that gastrointestinal digestion of purple rice had on its phenolic bioaccessibility and antioxidant activity.Our results demonstrated a significant difference(p<0.01)in bioaccessible phenolic content level and antioxidant activity between simulated gastric and intestinal digestion.However,mass spectrometry and ultra-high-performance liquid chromatography(UHPLC)coupled with online ABTS•+scavenging activity demonstrated a significant loss in the number of polyphenols that were bioaccessible after digestion.Interestingly,substantial free radical scavenging activity was retained after digestion due to the bioaccessibility of bioactive compounds such as tryptophan and protocatechuic acid.Hence,purple rice may be considered as a source of bioaccessible phenolic and antioxidant compounds.展开更多
The prebiotic functions of chocolate to improve the function and health benefit of the chocolate when enriched with probiotics has not been fully investigated.This study investigated the role of chocolates enriched wi...The prebiotic functions of chocolate to improve the function and health benefit of the chocolate when enriched with probiotics has not been fully investigated.This study investigated the role of chocolates enriched with probiotics in the production of SCFAs and vitamin B_(12) during the in-vitro colonic fermentation.Seven probiotic bacteria were encapsulated using a mixture of cocoa powder(10%),FOS(2%)and Na-alginate(1%)before added to chocolates.The results revealed that encapsulated Lactobacillus plantarum and Bifidobacterium animalis spp.lactis BB12 produced significantly higher amounts(1876.5±105.16 and 1348.51±77.37 mmol,respectively)of acetic acid after 48h of colonic fermentation.Chocolates with encapsulated BB12,La5,Lactobacillus sanfranciscensis and Streptococcus thermophilus yielded higher amounts of propionic,isobutyric,butyric and isovaleric acid.Probiotic-chocolates with 70%cocoa produced significantly more acetic,propionic,and butyric acids than that of 45%cocoa.However,Probiotic-chocolates with 45%cocoa produced greater amounts of vitamin B_(12) than 70%cocoa.These data demonstrate that probiotic-chocolate could be a functional snack with additional health benefits.展开更多
Hericium erinaceus polypeptide(HEP)was prepared by an ultrasound-microwave assisted enzymatic method.Using an ultrafiltration membrane with molecular weights of 5 and 10 kDa,HEP was fractionated into three fractions,n...Hericium erinaceus polypeptide(HEP)was prepared by an ultrasound-microwave assisted enzymatic method.Using an ultrafiltration membrane with molecular weights of 5 and 10 kDa,HEP was fractionated into three fractions,namely,(HEP-I(<5 kDa),HEP-II(5–10 kDa),and HEP-III(>10 kDa)).In vitro chemical methods were used to compare the antioxidant and hypolipidemic abilities of the polypeptide fractions from H.erinaceus before and after simulated gastrointestinal digestion.By constructing a hyperlipidemia model,the hypolipidemic ability of the high active fraction(HEP-II)was verified.The results showed that the antioxidant and hypolipidemic abilities of the polypeptide fractions from H.erinaceus did not change dramatically during simulated gastrointestinal digestion in vitro.The polypeptide fractions from H.erinaceus exhibited high tolerance to simulated gastrointestinal digestion in vitro,with strong antioxidant and hypolipidemic activities.HEP-II with a molecular weight of 5–10 kDa had the best stability,antioxidant,and hypolipidemic abilities in gastrointestinal digestion.The secondary structure of HEP-II was mainly composed of random coil(18.36%)andα-helix(47.71%)structures,which was beneficial to the hypolipidemic ability of HEP-II.Animal experiments showed that compared to the high-fat model group,HEP-II could inhibit the weight gain of the mice,decrease the liver index and serum levels of the serum total cholesterol(TC),triglycerides(TG),low-density lipoprotein cholesterol(LDL-C),nitric oxide synthase(NOS),alanine aminotransferase(AST),and glutamic-pyruvic transaminase(ALT),increase the levels of glutathione peroxidase(GSH-Px)and high-density lipoprotein cholesterol(HDL-C),decrease the arteriosclerosis index(AI),and improve the hemorheological indices of the mice.In addition,the whole blood and plasma viscosities of the mice decreased,and HEP-II increased the level of superoxide dismutase(SOD)in the liver,reducing the level of malondialdehyde(MDA),and the degree of oxidative stress in the liver of hypolipidemia mice.Furthermore,HEP-II improved liver steatosis.These results indicated that the polypeptide fractions from H.erinaceus all had a potential hypolipidemic effect,and HEP-II had the strongest potential hypolipidemic effect.展开更多
基金financially supported by the National Natural Science Foundation of China (32272359)Natural Science and Engineering Research Council of Canada (NSERC,RGPIN-2018-04680)the scholarship from the China Scholarship Council (202106670005)。
文摘Dry-fermented sausages are a good source of bioactive peptides,whose stability against gastrointestinal(GI)digestion determines their bioaccessibility.This study focused on evaluating the effect of peptide extracts from sausages fermented with Staphylococcus simulans QB7 during in vitro simulated GI digestion,including peptide profiles and antioxidant and anti-inflammatory activities.Peptides present in sausages were degraded during digestion,with molecular weight reduced from>12 kDa to<1.5 kDa.Besides,the content of amino acids increased from 381.15 to 527.07 mg/g,especially tyrosine being found only after GI digestion.The anti-inflammatory activities were increased after GI digestion,however,the changes in antioxidant activities were the opposite.A total number of 255,252 and 386 peptide sequences were identified in undigested,peptic-digested and GI-digested samples,respectively.PeptideRanker,BIOPEP-UWM and admetSAR were used to further predict the functional properties and intestinal absorption of the identified peptide sequences from GI digestion.Finally,18 peptides were discovered to possess either antioxidant or anti-inflammatory capacities.
基金supported by the Major special project of Anhui Province (2021d06050001)the Major Science and Technology Project of Anhui Province (201903b06020004)+1 种基金the Natural Science Foundation of Anhui Province (2308085QC115)the Special Fund for Anhui Province Agricultural Products Processing Industry Technology System (340000211260001000420)。
文摘The study evaluated the stability of an oligopeptide(Lys-Arg-Gln-Lys-Tyr-Asp,KRQKYD)and its transport mechanism by simulating gastrointestinal digestion and a model of human intestinal Caco-2 monolayer cells in vitro.In this study,the effects of environmental factors(temperature,pH and NaCl concentration)and simulated gastrointestinal digestion on the stability of KRQKYD were evaluated by indicators of the levels of alanine transaminase(ALT),aspartate transaminase(AST)and malondialdehyde(MDA)in an alcoholinduced hepatocyte injury model.The results showed that KRQKYD still maintained satisfactory hepatocyteprotective activity after treatment with different temperatures(20-80℃),pH(3.0-9.0),NaCl concentration(1%-7%)and simulated gastrointestinal digestion,which indicated that KRQKYD showed good stability to environmental factors and simulated gastrointestinal digestion.Furthermore,the intact KRQKYD could be absorbed in a model of Caco-2 monolayer cells with a P_(app)value of(9.70±0.53)×10^(-7)cm/s.Pretreatment with an energy inhibitor(sodium azide),a competitive peptide transporter inhibitor(Gly-Pro)and a transcytosis inhibitor wortmannin did not decrease the level of transepithelial KRQKYD transport,indicating that the transport mechanism of KRQKYD was not associated with energy dependent,vector mediated and endocytosis.The tight junction disruptor cytochalasin D significantly increased the level of transepithelial KRQKYD transport(P<0.05),suggesting that intact KRQKYD was absorbed by paracellular transport.
基金the financial support received from National Natural Science Foundation of China(No.31430067 and 31601475)China Postdoctoral Science Foundation funded project(No.2017M610200)Postdoctoral Foundation of Heilongjiang Province(No.LBH-Z17011)
文摘Peptides from Alcalase-hydrolyzed soybean protein hydrolysate(SPH)may hold the potential as natural antioxidants.In addition,the effect of human gastrointestinal(GI)tract on peptide bioavailability needs to be explored.In this study,the impact of simulated GI digestion and transepithelial transport on various antioxidant properties of SPH were investigated.SPH displayed DPPH radical scavenging(IC50=4.22 mg/m L),ABTS·+radical scavenging(IC50=2.93 mg/m L),reducing power and metal ion-chelating activities(IC50=0.67 mg/m L).Furthermore,SPH significantly(P<0.05)inhibited the generation of intracellular reactive oxygen species(ROS)in Caco-2 cells.After simulated GI digestion,the antioxidant properties of SPH were enhanced,except for a decrease in ABTS·+radical scavenging activity.After transepithelial transport,the permeates maintained partial antioxidant activity and the LC-MS/MS data further identified the absorbed soybean peptides.These results suggest that SPH contains the antioxidant peptides that are potentially bioavailable and can be regarded as a promising source of functional food ingredients.
基金Incubation Project on State Key Laboratory of Biological Resources and Ecological Environment of Qinba Areas,China(SLGPT2019KF04-04)and the ERDF through the COMPETE2020-Programa Operacional Competitividade e Internacionalização(POCI),Portugal。
文摘OBJECTIVE Epimedium is rich in a variety of beneficial active ingredients,and has been widely used in the ethnopharmacological practices,however,its biotransformation in gastrointestinal digestions remain unclear.This study aimed to investigate the dynamic changes of components and biological activity of Epimedium in the in vitro simulated digestion and subsequent human faecal fermentation.METHODS The models of in vitro simulated saliva,gastric and intestinal digestion,as well as colonic fermentation were constructed to simulate the digestion process of Epimedium.The dynamic changes of components of Epimedium during the simulated digestions in vitro and subsequent human faecal fermentation were investigated by UPLC-MS,HPLC-DAD combined with principal component analysis(PCA)and multi-ingredient quantitative analysis.RESULTS A variety of metabolites with high contents were produced after 0.5 h of intestinal digestion and colonic fermentation 0.5 h.Application of PCA to HPLC data showed the obvious separation of colonic fermentation 0.5 h stage samples from other colonic fermentation stages samples(24,48 and 72 h).Additionally,non-digestion and saliva digestion stage samples clustered together,and there was obvious separation between intestinal digestion samples and gastric digestion samples.The contents of epimedium C,icariin and baohuside I all increased significantly after intestinal digestion[58.70±7.08,47.15±5.68 and(12.78±0.55)mg·g^(-1)]compared with gastric digestion[29.00±5.65,17.40±4.55 and(2.77±0.19)mg·g^(-1)].There were significant differences between sample after 0.5 h of colonic fermentation[64.22±9.32,51.26±6.33 and(16.68±3.19)mg·g^(-1)]and other time points(24,48 and 72 h)in components and the contents of active ingredient,and the content of these components all decreased with the fermentation time.The ability of scavenging ABTS free radicals[IC50=(0.29±0.02)g·L^(-1)]increased significantly compared with gastric digestion[(1.57±0.02)g·L^(-1)],and after 0.5 h of colonic fermentation,the ability also increased significantly.CONCLUSION Gastrointestinal digestion had a significant impact on the contents of active components in Epimedium,and the metabolism of these components mainly occurred in the colon.The intestinal digestion and colonic fermentation significantly improved the anti-ABTS activity of epimedium.
基金Supported by the National Key R&D Program of China (No.2016YFC1402102)the National Natural Science Foundation of China (No.41976109)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)。
文摘The main protease(M^(pro))is essential for the replication of SARS-COV-2 and therefore represents a promising anti-viral target.In this study,we screened M^(pro)inhibitory peptides from Ulva prolifera protein on in-silico proteolysis.Cytotoxicity analysis using the online toxic prediction tool ToxinPred revealed that all the peptides were non-cytotoxic.The hexapeptide(SSGFID)exhibited high M^(pro)inhibitory activity in molecular docking and its IC_(50)value was 139.40±0.82μmol/L in vitro according to fluorescence resonance energy transfer assay(FRET).Quantitative real-time(qRT-)PCR results show that SSGFID could stimulate the expression of mitosis-related factors,including nuclear factor-κB,cyclin D1,and cyclin-dependent kinase 4,to promote the proliferation of mice splenocytes.Stability study revealed that SSGFID showed resistance against pepsin and trypsin but lost D(Asp)after pretreatment at121℃ for 15 min.Besides,SSGFID was mainly transported through the Caco-2 cell monolayer by the peptide transporter PepT1 and passive-mediated transport during the transport study.Unfortunately,the peptide was also degraded by Caco-2 intracellular enzymes,and the transfer rate of intact peptide was4.2%.Furthermore,Lineweaver–Burk plots demonstrated that SSGFID possessed a mixed inhibitory characteristic with M^(pro).Our study indicated the potential of Ulva prolifera as antiviral and immuneenhancing functional food ingredients and nutraceuticals.
基金financially supported by the National Natural Science Foundation of China (32130085)。
文摘Oysters(Crassostrea gigas)have a wide range of functionality due to their nutritional and bioactive components. However, the bioactive peptides of oyster proteins are rarely reported, particularly their antidiabetes effects and antioxidants. Oyster proteins were extracted from fresh oysters using phosphatebuffered saline and simulated gastrointestinal digestion was performed. The degree of hydrolysis(DH), structural characterization, molecular weight(Mw)distribution, free amino acid, anti-diabetic activity, and antioxidant activity were studied during in vitro simulated gastrointestinal digestion. The results showed that the α-glucosidase inhibitory activity, α-amylase inhibitory activity, DPPH radical scavenging activity, and ABTS radical scavenging activity of the oyster protein gastrointestinal digest were increased(P < 0.05)from 0 to 33.96%, from 9.17% to 44.22%, from 9.01 μg trolox/mg protein to 18.48 μg trolox/mg protein, and from 21.44 μg trolox/mg protein to 56.21 μg trolox/mg protein, respectively. Additionally, the DH, β-turn structure, fluorescence intensity, free amino acid, and short peptide content(Mw < 1 000 Da)increased in the simulated gastrointestinal digestion. These results indicate that the digestive hydrolysates obtained from oyster proteins could be used as natural anti-diabetic and antioxidant agents.
基金The authors would like to show deepest gratitude tothe Earmarked Fund for Jiangsu Agricultural Industry Technology System(JATS[2020]413)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX19_0682)forfinancial assistance.
文摘This study aimed to isolate and characterize the structures of glycoproteins from peas and determine their hypoglycemic activity.The crude pea glycoproteins(PGP)were extracted by hot water and purified by diethylaminoethyl(DEAE)-Sepharose chromatography and Sephadex G-100 size-exclusion chromatography in sequence.Then three main fractions were obtained,namely PGP1,PGP2 and PGP3,with molecular weights of 897615,846740 and 1194692 Da,respectively.The physical and chemical properties of the three fractions were evaluated and compared by Fourier transform infrared spectroscopy(FT-IR),nuclear magnetic resonance(NMR),scanning electron microscope(SEM),high performance liquid chromatography(HPLC)and other analytical techniques.The fraction PGP2 with the highest hypoglycemic activity,was screened using the Caco-2 monolayer cell model.It can inhibit the uptake of glucose in the small intestine,as well as the activities of maltase and sucrase.After simulated gastrointestinal digestion,PGP2 signifi cantly enhanced the inhibitory effect of α-glucosidase,and slightly reduced the inhibitory ability ofα-amylase.In summary,PGP2 possessed strong hypoglycemic activity after digestion.These results indicated that PGP2 has the potential to be developed into a functional food or natural medicine for the treatment of type 2 diabetes mellitus.
基金This work was supported by the Generalitat Valenciana[grant number:AICO/2018/289]Also,Ever Hern´andez-Olivas was a beneficiary of a pre-doctoral grant from the Mexican National Council of Science and Technology(CONACyT)[grant number:306682].
文摘This study aimed to in vitro evaluate the impact of common gastrointestinal(GI)alterations appearing with aging on protein digestibility,and functional related properties,in four different meats(chicken,turkey,pork and beef).Thus,three elderly digestion models were stated as long as altered GI conditions affected at oral(E1),oral and gastric(E2)and oral,gastric and intestinal stages(E3).Healthy adult GI conditions were also mimicked as standard control model(C).A notable trichloroacetic acid(TCA)soluble protein and the free amino acids(FAA)release reduction(p<0.05)were found under intestinal suboptimal conditions(E3),being more accused in beef than in other meats.Thus,chicken intake would be more advisable,than other meats,in terms of protein digestibility;while beef would provide a greater net supply of FAA under E3 model conditions.Gastric altered conditions,seem to favor protein solubility.Finally,while gastric and intestinal suboptimal conditions diminish the angiotensin converting enzyme(ACE)inhibition of meat digesta,their antioxidant activity was only negatively affected by intestinal altered conditions.
基金Project supported by the National Key Research and Development Program of China(No.2018YFD0400305)the Modern Agro-industry Technology Research System of China(No.CARS-40-K26)the“One Belt and One Road”International Science and Technology Cooperation Program of Zhejiang,China(No.2019C04022)。
文摘Immunoglobulin Y(Ig Y)is an effective orally administered antibody used to protect against various intestinal pathogens,but which cannot tolerate the acidic gastric environment.In this study,Ig Y was microencapsulated by alginate(ALG)and coated with chitooligosaccharide(COS).A response surface methodology was used to optimize the formulation,and a simulated gastrointestinal(GI)digestion(SGID)system to evaluate the controlled release of microencapsulated Ig Y.The microcapsule formulation was optimized as an ALG concentration of 1.56%(15.6 g/L),COS level of 0.61%(6.1 g/L),and Ig Y/ALG ratio of 62.44%(mass ratio).The microcapsules prepared following this formulation had an encapsulation efficiency of 65.19%,a loading capacity of 33.75%,and an average particle size of 588.75μm.Under this optimum formulation,the coating of COS provided a less porous and more continuous microstructure by filling the cracks on the surface,and thus the GI release rate of encapsulated Ig Y was significantly reduced.The release of encapsulated Ig Y during simulated gastric and intestinal digestion well fitted the zero-order and first-order kinetics functions,respectively.The microcapsule also allowed the Ig Y to retain 84.37%immune-activity after 4 h simulated GI digestion,significantly higher than that for unprotected Ig Y(5.33%).This approach could provide an efficient way to preserve Ig Y and improve its performance in the GI tract.
文摘Polyphenol-rich purple rice has been shown to exhibit a wide range of health properties including antioxidant activity.This study aimed to determine the impact that gastrointestinal digestion of purple rice had on its phenolic bioaccessibility and antioxidant activity.Our results demonstrated a significant difference(p<0.01)in bioaccessible phenolic content level and antioxidant activity between simulated gastric and intestinal digestion.However,mass spectrometry and ultra-high-performance liquid chromatography(UHPLC)coupled with online ABTS•+scavenging activity demonstrated a significant loss in the number of polyphenols that were bioaccessible after digestion.Interestingly,substantial free radical scavenging activity was retained after digestion due to the bioaccessibility of bioactive compounds such as tryptophan and protocatechuic acid.Hence,purple rice may be considered as a source of bioaccessible phenolic and antioxidant compounds.
文摘The prebiotic functions of chocolate to improve the function and health benefit of the chocolate when enriched with probiotics has not been fully investigated.This study investigated the role of chocolates enriched with probiotics in the production of SCFAs and vitamin B_(12) during the in-vitro colonic fermentation.Seven probiotic bacteria were encapsulated using a mixture of cocoa powder(10%),FOS(2%)and Na-alginate(1%)before added to chocolates.The results revealed that encapsulated Lactobacillus plantarum and Bifidobacterium animalis spp.lactis BB12 produced significantly higher amounts(1876.5±105.16 and 1348.51±77.37 mmol,respectively)of acetic acid after 48h of colonic fermentation.Chocolates with encapsulated BB12,La5,Lactobacillus sanfranciscensis and Streptococcus thermophilus yielded higher amounts of propionic,isobutyric,butyric and isovaleric acid.Probiotic-chocolates with 70%cocoa produced significantly more acetic,propionic,and butyric acids than that of 45%cocoa.However,Probiotic-chocolates with 45%cocoa produced greater amounts of vitamin B_(12) than 70%cocoa.These data demonstrate that probiotic-chocolate could be a functional snack with additional health benefits.
基金The study was financially supported by the Key Projects of the National Research and Development Program of China(2018YFD0400204).
文摘Hericium erinaceus polypeptide(HEP)was prepared by an ultrasound-microwave assisted enzymatic method.Using an ultrafiltration membrane with molecular weights of 5 and 10 kDa,HEP was fractionated into three fractions,namely,(HEP-I(<5 kDa),HEP-II(5–10 kDa),and HEP-III(>10 kDa)).In vitro chemical methods were used to compare the antioxidant and hypolipidemic abilities of the polypeptide fractions from H.erinaceus before and after simulated gastrointestinal digestion.By constructing a hyperlipidemia model,the hypolipidemic ability of the high active fraction(HEP-II)was verified.The results showed that the antioxidant and hypolipidemic abilities of the polypeptide fractions from H.erinaceus did not change dramatically during simulated gastrointestinal digestion in vitro.The polypeptide fractions from H.erinaceus exhibited high tolerance to simulated gastrointestinal digestion in vitro,with strong antioxidant and hypolipidemic activities.HEP-II with a molecular weight of 5–10 kDa had the best stability,antioxidant,and hypolipidemic abilities in gastrointestinal digestion.The secondary structure of HEP-II was mainly composed of random coil(18.36%)andα-helix(47.71%)structures,which was beneficial to the hypolipidemic ability of HEP-II.Animal experiments showed that compared to the high-fat model group,HEP-II could inhibit the weight gain of the mice,decrease the liver index and serum levels of the serum total cholesterol(TC),triglycerides(TG),low-density lipoprotein cholesterol(LDL-C),nitric oxide synthase(NOS),alanine aminotransferase(AST),and glutamic-pyruvic transaminase(ALT),increase the levels of glutathione peroxidase(GSH-Px)and high-density lipoprotein cholesterol(HDL-C),decrease the arteriosclerosis index(AI),and improve the hemorheological indices of the mice.In addition,the whole blood and plasma viscosities of the mice decreased,and HEP-II increased the level of superoxide dismutase(SOD)in the liver,reducing the level of malondialdehyde(MDA),and the degree of oxidative stress in the liver of hypolipidemia mice.Furthermore,HEP-II improved liver steatosis.These results indicated that the polypeptide fractions from H.erinaceus all had a potential hypolipidemic effect,and HEP-II had the strongest potential hypolipidemic effect.
