Increased circulating branched-chain amino acids(BCAAs)have been involved in the pathogenesis of obesity and insulin resistance.However,evidence relating berberine(BBR),gut microbiota,BCAAs,and insulin resis⁃tance is ...Increased circulating branched-chain amino acids(BCAAs)have been involved in the pathogenesis of obesity and insulin resistance.However,evidence relating berberine(BBR),gut microbiota,BCAAs,and insulin resis⁃tance is limited.Here,we showed that BBR could effectively rectify steatohepatitis and glucose intolerance in high-fat diet(HFD)-fed mice.BBR reorganized gut microbiota populations under both the normal chow diet(NCD)and HFD.Particu⁃larly,BBR noticeably decreased the relative abundance of BCAA-producing bacteria,including order Clostridiales;fami⁃lies Streptococcaceae,Clostridiaceae,and Prevotellaceae;and genera Streptococcus and Prevotella.Compared with the HFD group,predictive metagenomics indicated a reduction in the proportion of gut microbiota genes involved in BCAA biosynthesis but the enrichment genes for BCAA degradation and transport by BBR treatment.Accordingly,the elevated serum BCAAs of HFD group were significantly decreased by BBR.Furthermore,the Western blotting results implied that BBR could promote the BCAA catabolism in the liver and epididymal white adipose tissues of HFD-fed mice by acti⁃vation of the multienzyme branched-chain α-ketoacid dehydrogenase complex,whereas by inhibition of the phosphoryla⁃tion state of BCKDHA(E1α subunit)and branched-chain α-ketoacid dehydrogenase kinase.The ex vivo assay further confirmed that BBR could increase BCAA catabolism in both AML12 hepatocytes and 3T3-L1 adipocytes.Finally,data from healthy subjects and diabetics confirmed that BBR could improve glycemic control and modulate circulating BCAAs.Besides,functional microbiomics integrated high-throughput microbial genomics,metabolomics and molecular biotechnology has also been successfully applied to reveal the anti-obesity mechanism of hydroxysafflor yellow A.展开更多
To investigate the effects of aluminium （Al） exposure on amino acid neurotransmitters, the chickens with different levels of subchronic Al poisoning were estabolished by continuous peritoneal injection of fixed volu...To investigate the effects of aluminium （Al） exposure on amino acid neurotransmitters, the chickens with different levels of subchronic Al poisoning were estabolished by continuous peritoneal injection of fixed volume and different concentrations of gradient of aluminium trichloride （AlCl3）. The levels of amino acid neurotransmitters in chicken brains were determined by high performance liquid chromatography （HPLC） after being exposed of Al for 60 days, and Al levels in serum and brain tissue were determined by atomic absorption spectrophotometry （AAS）. The results showed that Glu levels increased with the increase of Al, but there was no significant difference compared with the control. The levels of Al, Asp, Gly, GABA and Tau were significantly higher in Al-treated groups than those in the control. The results indicated that Al intoxication led to excitatory neurotoxicity.展开更多
Background:Low insecticidal protein expression at reproductive organs affect insect resistance in Bt transgenic cotton.In order to enhance flower insecticidal protein expression,the conventional cultivar Sikang1(S1)an...Background:Low insecticidal protein expression at reproductive organs affect insect resistance in Bt transgenic cotton.In order to enhance flower insecticidal protein expression,the conventional cultivar Sikang1(S1)and the hybrid cultivar Sikang3(S3)were used as experimental materials;the applications of selected 5 types of amino acids and 21 types of amino acids were sprayed on the flowers in 2016 and 2017 cotton growing seasons.Results:The flower Bt protein contents increased significantly under the two amino acid treatments in both cultivars,the Bt protein concentration increased by 15.2 to 25.8%compared with the control.However,no significant differences were detected between the two treatments of amino acid application.Increased amino acid and soluble protein contents,enhanced GPT,GOT,protease,and peptidase activities were observed under the amino acid application at the flowering stage.Conclusions:These results suggest that exterior application of the amino acids treatments could bolster the flower insecticidal protein expression.展开更多
In this study,the hydrolytic amino acids of Chinese human and Holstein cow milk of different lactation periods were analyzed by the advanced isobaric tags for relative and absolute quantitation(iTRAQ)combined with the...In this study,the hydrolytic amino acids of Chinese human and Holstein cow milk of different lactation periods were analyzed by the advanced isobaric tags for relative and absolute quantitation(iTRAQ)combined with the high performance liquid chromatography-mass spectrometry(HPLC-MS/MS)approach.The total contents of the hydrolytic amino acids in cow colostrum,cow mature milk,human colostrum and human mature milk were 5.00,4.38,2.12 and 2.48 g·L^(-1),respectively.Among these,the contents of the hydrolytic amino acids in cow milk were higher than those in human milk,indicating a decreasing trend with the prolongation of lactation.Additionally,principal component and hierarchical cluster analyses were used to further screen the differentially expressed amino acids.These results enhanced the understanding of the hydrolytic amino acids in cow and human milk across different lactation periods,which could provide potential directions for newborn dairy powder and nutritious supplementary.展开更多
The nitrogen (N) metabolic experiments were made to estimate separately amino acid requirements of 4348 weeks old layers for maintenance, for protein accretion to estabolish models to estimate digestible amino acid re...The nitrogen (N) metabolic experiments were made to estimate separately amino acid requirements of 4348 weeks old layers for maintenance, for protein accretion to estabolish models to estimate digestible amino acid requirements. The regression relationship of nitrogen retention vs amino acid intake was estimated for each amino acid by giving, at rate of N intake of 091, 052, 015 and 0007gkg-1 body-weight (W075) per d, the semi-synthetic diets was made specially deficient in one amino acid. From the regression coefficients, it was calculated that, for the accretion of 1 g protein, the dietary digestible amino acid requirements were (mg) Thr 631, Val 1004, Met 399, Ile 886, Leu 1143, Phe 632, Lys 870, His 205, Arg 879, Trp 214, Met+Cys 776, and Phe+Tyr 1143. Daily amino acid requirements for N equilibrium were estimated to be (mgkg-1W075 per day) Thr 506, Val 747, Met 303, ILe 667 Leu 814, Phe 448, Lys 605 His 147, Arg 739 ,Trp 173, Met+Cys 586, and Phe+Tyr 839 The dietary degestible amino acid patterns for protein accretion and N equilibrium were also proposed. The models of estimating digestible amino acid requirements for the different productions were developed.展开更多
Fermented soybean is one of the traditional foods widely consumed in many Asian countries. Most products（i.e., Natto, Jang, Kinema and Thua nao） are produced mainly by the bacterial activity. This study was performe...Fermented soybean is one of the traditional foods widely consumed in many Asian countries. Most products（i.e., Natto, Jang, Kinema and Thua nao） are produced mainly by the bacterial activity. This study was performed as a part of the program to improve the soybean fermentation, and a use of the co-culture between the bacterium Bacillus subtilis and the fungus Rhizopus oligosporus was selected. For fermentation, the raw soybeans were washed, sterilized by autoclaving, and inoculated with a mixed microbial starter culture of B. subtilis（102 CFU · g-1） and R. oligosporus（102 conidia · g-1）. The Free Amino Acid（FAA） contents were then investigated by using High Performance Liquid Chromatography（HPLC）. The results showed that the amounts of FAAs and essential amino acids in the fermented soybean samples were found at significantly higher concentration when compared to those of the cooked, non-fermented soybean samples（p〈0.05）. These data indicated that an involvement of microbial fermentation helped to accelerate an increase of FAA. The food compositional data were useful as a reference（and/or guidance） for the nutritional value, when compared to other fermented soybeans and related products.展开更多
The aim of this study was to investigate the effect of duodenal infusion of soybean small peptides(SSP) on mammary uptake of amino acids(AA).Eight Chinese Saanen goats with duodenal fistulae and catheters were used in...The aim of this study was to investigate the effect of duodenal infusion of soybean small peptides(SSP) on mammary uptake of amino acids(AA).Eight Chinese Saanen goats with duodenal fistulae and catheters were used in a crossover design trial.Goats were infused with 0,60,120,180 g/d SSP.The experimental period lasted for 14 d.The results showed:1) milk protein yield and content were increased,with the increment in milk protein yield being significant(P【0.05).Milk fat yield and content were decreased with the increased amount of SSP infused(P【0.05).2) Mammary plasma flow was not changed(P】0.05) by SSP infusion though the average was slightly higher.Mammary plasma flow/milk yield was decreased by SSP infusion and there was significant difference between the 120 g/d treatment and the control(P【0.05).3) Compared with the control treatment,uptakes of most free amino acids were increased in the 60 and 120 g/d treatments,but decreased by the 180 g/d treatment.The uptakes of all peptide-bound essential amino acids(PB-EAA) were increased except for PB-Ile.Uptake of PB-Val,PB-Leu, PB-Phe,PB-Thr,PB-Met and PB-Lys was highest in the 120 g/d treatment.Among the peptide-bound nonessential amino acids(PB-NEAA),uptake of PB-Ser,PB-Tyr,and PB-Pro was increased(P【0.05) while that of PB-Gly was decreased(P】0.05).4) With the exception of Lys,secretion of all essential AA(EAA) was increased by SSP infusion from 0-120 g/d(P【0.05),while in the 180 g/d treatment the increase was not significant and was lower than that in the 120 g/d treatment.5) The expression of APN was increased by SSP;in the 60,120,180 g/d treatments expression was 13.55-,18.69-,and 10.01-fold over that of the controls.Conclusion:SSP might be used as substrates for milk protein synthesis by mammary gland,and can increase synthesis and secretion of milk protein.There was reason to believe that uptake and use of AA was either saturated or inhibited at high levels of infusion of SSP.Increased APN expression with infusion of SSP related to mammary uptake of PBAA by mammary gland,which suggested that APN was one of the peptidases regulating use of AA from small peptides in mammary tissue.展开更多
The amino acid Schiff base complex (Sal-AMBA-Mn) was prepared with p-amino-methylbenzoic acid, salicylaldehyde and Mn(OAc)2·4H2O. Its structures was characterized with IR and UV spectra. Oxygenation mechanism of ...The amino acid Schiff base complex (Sal-AMBA-Mn) was prepared with p-amino-methylbenzoic acid, salicylaldehyde and Mn(OAc)2·4H2O. Its structures was characterized with IR and UV spectra. Oxygenation mechanism of the complex in N, N-dimethylformamide solution was investigated. The results show that lower temperature is in favor of the oxygenation, and energy, enthalpy and entropy are -3.8 kJ/mol, -4.2 J/mol and -161.44 J/(mol·K), respectively. In the presence of the manganese complex, dehydroepiandrosterone acetate is effectively oxidized by molecular oxygen and the corresponding enone 7-ketodehydroepiandrosterone acetate is obtained. The yield is 62.1% when the oxidation is carried out under the reaction conditions of 60 ℃, 2 MPa of O2 pressure, C5H5N as a solvent and molar ratio of the substrate to the complex of 1:10.展开更多
G-protein coupled receptors（GPCRs） have a relatively conservative seven transmembrane helix（7tm） regions, and their N and C termini are various. In order to strengthen the features of GPCR families, N and C termin...G-protein coupled receptors（GPCRs） have a relatively conservative seven transmembrane helix（7tm） regions, and their N and C termini are various. In order to strengthen the features of GPCR families, N and C termini were removed in this study, then frequency features in the form of single amino acid and dipeptide compositions for recognition of human GPCRs were analyzed and extracted based on the compressed amino acid alphabets. Based on these features, classifiers were developed using support vector machine（SVM）. The ability of different compressed methods was investigated. The testing results demonstrated that the suitable choice of compressed method combined with amino acid composition information could get good performance for the recognition of human GPCRs.展开更多
A new chemical index-imbalance degree (IBD), was proposed on the basis of cluster analysis in multivariate statistical analysis to estimate the extent of amino acid balance in protein. The range of IBD is between 0 an...A new chemical index-imbalance degree (IBD), was proposed on the basis of cluster analysis in multivariate statistical analysis to estimate the extent of amino acid balance in protein. The range of IBD is between 0 and 1, successively corresponding to complete balance and entire imbalance for the amino acid profile of a sample. The amino acid increment model of IBD belongs to an asymmetrical maximum-type, and there is a high correlation between IBD and coefficient of variation (CV). The nutritional value of individual feed can be ranked and clustered according to its IBD; and by calculating the IBD of amixed sample with two or more feedstuffs, it is Possible theoretically to predict whether a synergetic. pheno men on exists and when an optimal mutual complement can happen. If the conceptive frame of IBD extended, it can be used to study the balance of nutrients besides amino acids, and is helpful to realize the automatic distinction and selection in diet formulating.展开更多
In this study,a total of 36 blackcurrant(Ribes nigrum L.)cultivars grown in the Northeast of China were selected,including 12 cultivars introduced from Russia,10 from Poland and the rest from local areas.The physicoch...In this study,a total of 36 blackcurrant(Ribes nigrum L.)cultivars grown in the Northeast of China were selected,including 12 cultivars introduced from Russia,10 from Poland and the rest from local areas.The physicochemical properties and amino acid compositions of these varieties were studied,and the geographical origins of blackcurrants were tracked by multivariate statistical analysis.A total of 23 amino acids were detected in all cultivars,which were rich in glutamine,glutamate,aspartate,asparagine,α-alanine,γ-aminobutyric acid,valine and serine.The content of the total amino acids in these cultivars was from 31.21 mg•100 g-1 to 319.40 mg•100 g-1.Stepwise linear discriminant analysis(SLDA)was introduced to perform satisfactory categorization for blackcurrant cultivars,which achieved a success rate of 88.9%for the identification of geographical origins.These results suggested that the compositions of amino acids in blackcurrants could effectively predict geographical origins.展开更多
The effects of the deficiency of the allergenicα-subunit on soybean amino acid(AA)composition were studied using the cultivar Dongnong 47(DN47)as a genetic background.The near-isogenic line(NIL)NIL-DN47-Δα of DN47,...The effects of the deficiency of the allergenicα-subunit on soybean amino acid(AA)composition were studied using the cultivar Dongnong 47(DN47)as a genetic background.The near-isogenic line(NIL)NIL-DN47-Δα of DN47,with an introgression of theα-null trait allele from the high protein donor parent RiB,was created by marker assisted background selection and used to investigate the AA content and nutritional quality.The contents of crude protein,the total AAs,the total essential amino acids(EAAs)and sulfur-containing(Met and Cys)AAs increased by 4.11%,4.16%,5.20% and 11.96%,respectively in NIL-DN47-Δα compared with DN47.Analyses of the total EAAs(TEAAs)and the EAA index(EAAI)revealed that both parameters in NIL-DN47-Δα were higher than those in DN47.The null-allele of theα-subunit positively affected the AA scores.The quantitative changes in free AAs(FAAs)in the developing seeds of NIL-DN47-Δα and DN47 were compared as of 15 days after flowering(DAF)until maturity.The results showed that the total FAA content in NIL-DN47-Δα was significantly higher than that in the DN47 throughout the late maturation stage(40-60 DAF)of seeds.The high concentration of the FAAs in cgy-2 mutant seeds was a consequence of the high rates of synthesis and/or accumulation of individual FAAs during seed maturation where 25 DAF was an important turning point in the accumulation of the FAAs.The FAA contents of single soybeanα-null,double(α+α′)and triple(α+α′+group I)-null mutant combination lines were investigated.In all of these combinations,introduction of the cgy-2 gene invariably raised the FAA content of mature seeds above that of the DN47.In summary,the enhanced protein quality in cgy-2 mutants resulted from several factors.(1)There was a general increase in the contents of most AAs and FAAs in NIL-DN47-Δα.(2)The induced synthesis of free Arg contributed effectively to the high FAAs of various storage-protein-deficiency mutants.For example,in the S2(null α,group I),the free Arg content was seven times as much as that of DN47,accounting for more than half of the total FAA content in the seed.(3)The increase of sulfur-containing AAs in theα-null type NIL mainly resulted from elevated Met content.These data suggested that the cgy-2 mutation might improve the protein quality of soybean seeds and that lacked of the allergenicα-subunit resulted in increased the FAA content.展开更多
HPLC-MS/MS methods were developed to determine 19 kinds of free amino acids in human serum. API 4000 and Quattro Ultima HPLC-MS/MS systems were used in this study. The established method proved to be fast and specific...HPLC-MS/MS methods were developed to determine 19 kinds of free amino acids in human serum. API 4000 and Quattro Ultima HPLC-MS/MS systems were used in this study. The established method proved to be fast and specific.It can be applied to determine 19 kinds of amino acids simultaneously and also can be used in the disease screening studies associated with amino acids disorders.展开更多
This study aimed to investigate the effects of dietary guanidinoacetic acid on growth performance,meat quality,antioxidant activity,and antioxidant-related gene expression in ducks.Total 48042-day-old female ducks wer...This study aimed to investigate the effects of dietary guanidinoacetic acid on growth performance,meat quality,antioxidant activity,and antioxidant-related gene expression in ducks.Total 48042-day-old female ducks were randomly divided into four groups with six replicates and 20 ducks per replicate and fed the basal diet to the control group.The experimental groups were fed the basal diet with 400,600 and 800 mg·kg^(-1) guanidinoacetic acid,respectively.The trial lasted 48 days.Compared with the control group,(1)the body weight at 90 days and average daily gain were increased(P<0.05),the feed conservation ratio was decreased(P<0.05);(2)the dressing percentage and breast muscle percentage were increased(P<0.05);(3)the total amino acid content,polyunsaturated fatty acids to monounsaturated fatty acids ratio were increased(P<0.05)in breast and thigh muscles;(4)activities of superoxide dismutase,catalase and glutathione peroxidase enzyme were increased(P<0.05)in thigh muscles;(5)the relative expressions of superoxide dismutase 1,glutathione peroxidase 1,and catalase were significantly increased(P<0.05)in the liver.In this study,the optimum dosage of 600 mg·kg^(-1) guanidinoacetic acid improved the growth performance,meat quality,antioxidant activity,and antioxidant-related gene expression in ducks.展开更多
Growth and osmotic response of Lactobacillus bulgaricus ATCC 11842 under hyperosmotic constraint were investigated in a chemically defined medium （CDM） and MRS medium. NaCl could inhibit the growth of L. bulgaricus ...Growth and osmotic response of Lactobacillus bulgaricus ATCC 11842 under hyperosmotic constraint were investigated in a chemically defined medium （CDM） and MRS medium. NaCl could inhibit the growth of L. bulgaricus which decreased with increasing NaCl concentration. In the MRS, NaCl of 1.0 mol·L-1 was the biggest salt stress concentration; in the CDM, 0.8 mol·L-1 was the biggest inhibition concentration. In contrast to what was observed in other lactic acid bacteria, proline, glycine betaine and related molecules were unable to relieve inhibition of growth of L. bulgaricus under osmotic constraint. This was correlated to the absence of sequences homologous to the genes coding for glycine-betaine and/or proline transporters described in Lactococcus lactis and Bacillus subtilis. The amino acid aspartate and alanine were proved to be osmoprotective under NaCl stress. Addition of peptone （0.25% w/v） in the presence of salt led to a stimulation of the growth, as the decrease of the lag time and generation time, and the final biomass increased from 0.31 to 0.64.展开更多
The synergistic inhibition effect of CeCl3(Ce)and serine(Ser)on the corrosion of carbon steel in a 3%NaCl solution was investigated by electrochemical methods and surface analysis.The results showed that both CeCl3 an...The synergistic inhibition effect of CeCl3(Ce)and serine(Ser)on the corrosion of carbon steel in a 3%NaCl solution was investigated by electrochemical methods and surface analysis.The results showed that both CeCl3 and Ser,when used alone,had limited inhibition effect toward carbon steel corrosion in the 3%NaCl solution.In contrast,the combination of CeCl3 with Ser produced a strong synergistic effect on the corrosion inhibition behavior of carbon steel,improving the inhibition efficiency significantly.The polarization curves showed that the mixture of CeCl3 and Ser acts as a cationic-type inhibitor.Scanning electron microscopy and Fourier transform infrared spectroscopy showed that the synergistic inhibition effect was due to complex formation between the cerium ions and amino acid molecules.展开更多
D,L-lactide was prepared from D,L-lactic acid by means of polymerization and depolymerization at low vacuum level.Morpholine-2,5-dione(MD) was synthesized from the cyclization of chloroacetyl glycine which was made fr...D,L-lactide was prepared from D,L-lactic acid by means of polymerization and depolymerization at low vacuum level.Morpholine-2,5-dione(MD) was synthesized from the cyclization of chloroacetyl glycine which was made from chloroacetyl chloride and glycine in the basic condition.A novel copolymer(PLAMD) with D,L-lactide(D,L-LA) and morpholine-2,5-dione(MD) was synthesized using stannous octoate as initiator,and characterized with FT-IR and 1HNMR.The biocompatibility of PLAMD and PLA was investigated by MTT and microscope.The results show that amino acid is introduced into PDLLA main chain.PLAMD has better cell affinity than PLA,so it is a promising biomaterial.展开更多
文摘Increased circulating branched-chain amino acids(BCAAs)have been involved in the pathogenesis of obesity and insulin resistance.However,evidence relating berberine(BBR),gut microbiota,BCAAs,and insulin resis⁃tance is limited.Here,we showed that BBR could effectively rectify steatohepatitis and glucose intolerance in high-fat diet(HFD)-fed mice.BBR reorganized gut microbiota populations under both the normal chow diet(NCD)and HFD.Particu⁃larly,BBR noticeably decreased the relative abundance of BCAA-producing bacteria,including order Clostridiales;fami⁃lies Streptococcaceae,Clostridiaceae,and Prevotellaceae;and genera Streptococcus and Prevotella.Compared with the HFD group,predictive metagenomics indicated a reduction in the proportion of gut microbiota genes involved in BCAA biosynthesis but the enrichment genes for BCAA degradation and transport by BBR treatment.Accordingly,the elevated serum BCAAs of HFD group were significantly decreased by BBR.Furthermore,the Western blotting results implied that BBR could promote the BCAA catabolism in the liver and epididymal white adipose tissues of HFD-fed mice by acti⁃vation of the multienzyme branched-chain α-ketoacid dehydrogenase complex,whereas by inhibition of the phosphoryla⁃tion state of BCKDHA(E1α subunit)and branched-chain α-ketoacid dehydrogenase kinase.The ex vivo assay further confirmed that BBR could increase BCAA catabolism in both AML12 hepatocytes and 3T3-L1 adipocytes.Finally,data from healthy subjects and diabetics confirmed that BBR could improve glycemic control and modulate circulating BCAAs.Besides,functional microbiomics integrated high-throughput microbial genomics,metabolomics and molecular biotechnology has also been successfully applied to reveal the anti-obesity mechanism of hydroxysafflor yellow A.
基金Supported by the Science and Technology Program of Helongjiang Educational Bureau (12511028)the Postgraduate Innovative Scientific Research Foundation of Heilongjiang Province (YJSCX2012-026HLJ)
文摘To investigate the effects of aluminium （Al） exposure on amino acid neurotransmitters, the chickens with different levels of subchronic Al poisoning were estabolished by continuous peritoneal injection of fixed volume and different concentrations of gradient of aluminium trichloride （AlCl3）. The levels of amino acid neurotransmitters in chicken brains were determined by high performance liquid chromatography （HPLC） after being exposed of Al for 60 days, and Al levels in serum and brain tissue were determined by atomic absorption spectrophotometry （AAS）. The results showed that Glu levels increased with the increase of Al, but there was no significant difference compared with the control. The levels of Al, Asp, Gly, GABA and Tau were significantly higher in Al-treated groups than those in the control. The results indicated that Al intoxication led to excitatory neurotoxicity.
基金The Projects#2017YFD0201306,#2018YFD0100406 supported by the National Key R&D Program of China#31671613 supported by National Natural Science Foundation of China+1 种基金Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China(PAPD)Project#2016PCTS-1 supported by the Chinese academy of agricultural sciences’engineering science and technology innovation fund
文摘Background:Low insecticidal protein expression at reproductive organs affect insect resistance in Bt transgenic cotton.In order to enhance flower insecticidal protein expression,the conventional cultivar Sikang1(S1)and the hybrid cultivar Sikang3(S3)were used as experimental materials;the applications of selected 5 types of amino acids and 21 types of amino acids were sprayed on the flowers in 2016 and 2017 cotton growing seasons.Results:The flower Bt protein contents increased significantly under the two amino acid treatments in both cultivars,the Bt protein concentration increased by 15.2 to 25.8%compared with the control.However,no significant differences were detected between the two treatments of amino acid application.Increased amino acid and soluble protein contents,enhanced GPT,GOT,protease,and peptidase activities were observed under the amino acid application at the flowering stage.Conclusions:These results suggest that exterior application of the amino acids treatments could bolster the flower insecticidal protein expression.
基金Supported by the National Key R&D Program of China(2018YFC1604302)the"Twelfth-Five Year"National Science and Technology Plan Project(2013BAD18B03)+2 种基金Shenyang Technological Innovation Project(Y17-0-028)Liaoning Revitalization Talents Program(XLYC1902083)Liaoning Distinguished Professor Project。
文摘In this study,the hydrolytic amino acids of Chinese human and Holstein cow milk of different lactation periods were analyzed by the advanced isobaric tags for relative and absolute quantitation(iTRAQ)combined with the high performance liquid chromatography-mass spectrometry(HPLC-MS/MS)approach.The total contents of the hydrolytic amino acids in cow colostrum,cow mature milk,human colostrum and human mature milk were 5.00,4.38,2.12 and 2.48 g·L^(-1),respectively.Among these,the contents of the hydrolytic amino acids in cow milk were higher than those in human milk,indicating a decreasing trend with the prolongation of lactation.Additionally,principal component and hierarchical cluster analyses were used to further screen the differentially expressed amino acids.These results enhanced the understanding of the hydrolytic amino acids in cow and human milk across different lactation periods,which could provide potential directions for newborn dairy powder and nutritious supplementary.
文摘The nitrogen (N) metabolic experiments were made to estimate separately amino acid requirements of 4348 weeks old layers for maintenance, for protein accretion to estabolish models to estimate digestible amino acid requirements. The regression relationship of nitrogen retention vs amino acid intake was estimated for each amino acid by giving, at rate of N intake of 091, 052, 015 and 0007gkg-1 body-weight (W075) per d, the semi-synthetic diets was made specially deficient in one amino acid. From the regression coefficients, it was calculated that, for the accretion of 1 g protein, the dietary digestible amino acid requirements were (mg) Thr 631, Val 1004, Met 399, Ile 886, Leu 1143, Phe 632, Lys 870, His 205, Arg 879, Trp 214, Met+Cys 776, and Phe+Tyr 1143. Daily amino acid requirements for N equilibrium were estimated to be (mgkg-1W075 per day) Thr 506, Val 747, Met 303, ILe 667 Leu 814, Phe 448, Lys 605 His 147, Arg 739 ,Trp 173, Met+Cys 586, and Phe+Tyr 839 The dietary degestible amino acid patterns for protein accretion and N equilibrium were also proposed. The models of estimating digestible amino acid requirements for the different productions were developed.
基金Supported by the Asia Research Centre,Chulalongkorn University(005/2559)Mae Fah Luang University
文摘Fermented soybean is one of the traditional foods widely consumed in many Asian countries. Most products（i.e., Natto, Jang, Kinema and Thua nao） are produced mainly by the bacterial activity. This study was performed as a part of the program to improve the soybean fermentation, and a use of the co-culture between the bacterium Bacillus subtilis and the fungus Rhizopus oligosporus was selected. For fermentation, the raw soybeans were washed, sterilized by autoclaving, and inoculated with a mixed microbial starter culture of B. subtilis（102 CFU · g-1） and R. oligosporus（102 conidia · g-1）. The Free Amino Acid（FAA） contents were then investigated by using High Performance Liquid Chromatography（HPLC）. The results showed that the amounts of FAAs and essential amino acids in the fermented soybean samples were found at significantly higher concentration when compared to those of the cooked, non-fermented soybean samples（p〈0.05）. These data indicated that an involvement of microbial fermentation helped to accelerate an increase of FAA. The food compositional data were useful as a reference（and/or guidance） for the nutritional value, when compared to other fermented soybeans and related products.
文摘The aim of this study was to investigate the effect of duodenal infusion of soybean small peptides(SSP) on mammary uptake of amino acids(AA).Eight Chinese Saanen goats with duodenal fistulae and catheters were used in a crossover design trial.Goats were infused with 0,60,120,180 g/d SSP.The experimental period lasted for 14 d.The results showed:1) milk protein yield and content were increased,with the increment in milk protein yield being significant(P【0.05).Milk fat yield and content were decreased with the increased amount of SSP infused(P【0.05).2) Mammary plasma flow was not changed(P】0.05) by SSP infusion though the average was slightly higher.Mammary plasma flow/milk yield was decreased by SSP infusion and there was significant difference between the 120 g/d treatment and the control(P【0.05).3) Compared with the control treatment,uptakes of most free amino acids were increased in the 60 and 120 g/d treatments,but decreased by the 180 g/d treatment.The uptakes of all peptide-bound essential amino acids(PB-EAA) were increased except for PB-Ile.Uptake of PB-Val,PB-Leu, PB-Phe,PB-Thr,PB-Met and PB-Lys was highest in the 120 g/d treatment.Among the peptide-bound nonessential amino acids(PB-NEAA),uptake of PB-Ser,PB-Tyr,and PB-Pro was increased(P【0.05) while that of PB-Gly was decreased(P】0.05).4) With the exception of Lys,secretion of all essential AA(EAA) was increased by SSP infusion from 0-120 g/d(P【0.05),while in the 180 g/d treatment the increase was not significant and was lower than that in the 120 g/d treatment.5) The expression of APN was increased by SSP;in the 60,120,180 g/d treatments expression was 13.55-,18.69-,and 10.01-fold over that of the controls.Conclusion:SSP might be used as substrates for milk protein synthesis by mammary gland,and can increase synthesis and secretion of milk protein.There was reason to believe that uptake and use of AA was either saturated or inhibited at high levels of infusion of SSP.Increased APN expression with infusion of SSP related to mammary uptake of PBAA by mammary gland,which suggested that APN was one of the peptidases regulating use of AA from small peptides in mammary tissue.
基金Project(76132020) supported by the Post-Doctoral Science Fund of Central South University
文摘The amino acid Schiff base complex (Sal-AMBA-Mn) was prepared with p-amino-methylbenzoic acid, salicylaldehyde and Mn(OAc)2·4H2O. Its structures was characterized with IR and UV spectra. Oxygenation mechanism of the complex in N, N-dimethylformamide solution was investigated. The results show that lower temperature is in favor of the oxygenation, and energy, enthalpy and entropy are -3.8 kJ/mol, -4.2 J/mol and -161.44 J/(mol·K), respectively. In the presence of the manganese complex, dehydroepiandrosterone acetate is effectively oxidized by molecular oxygen and the corresponding enone 7-ketodehydroepiandrosterone acetate is obtained. The yield is 62.1% when the oxidation is carried out under the reaction conditions of 60 ℃, 2 MPa of O2 pressure, C5H5N as a solvent and molar ratio of the substrate to the complex of 1:10.
基金Supported by the Natural Science Foundation of Ningxia University(ZR1124)
文摘G-protein coupled receptors（GPCRs） have a relatively conservative seven transmembrane helix（7tm） regions, and their N and C termini are various. In order to strengthen the features of GPCR families, N and C termini were removed in this study, then frequency features in the form of single amino acid and dipeptide compositions for recognition of human GPCRs were analyzed and extracted based on the compressed amino acid alphabets. Based on these features, classifiers were developed using support vector machine（SVM）. The ability of different compressed methods was investigated. The testing results demonstrated that the suitable choice of compressed method combined with amino acid composition information could get good performance for the recognition of human GPCRs.
文摘A new chemical index-imbalance degree (IBD), was proposed on the basis of cluster analysis in multivariate statistical analysis to estimate the extent of amino acid balance in protein. The range of IBD is between 0 and 1, successively corresponding to complete balance and entire imbalance for the amino acid profile of a sample. The amino acid increment model of IBD belongs to an asymmetrical maximum-type, and there is a high correlation between IBD and coefficient of variation (CV). The nutritional value of individual feed can be ranked and clustered according to its IBD; and by calculating the IBD of amixed sample with two or more feedstuffs, it is Possible theoretically to predict whether a synergetic. pheno men on exists and when an optimal mutual complement can happen. If the conceptive frame of IBD extended, it can be used to study the balance of nutrients besides amino acids, and is helpful to realize the automatic distinction and selection in diet formulating.
基金Supported by the National Natural Science Foundation of China(32172521)the Natural Science Fund Joint Guidance Project of Heilongjiang Province(LH2019C031)+1 种基金Postdoctoral Scientific Research Development Fund of Heilongjiang Province,China(LBH-Q16020)the Natural Science Fund Project of Heilongjiang Province(SS2021C001)。
文摘In this study,a total of 36 blackcurrant(Ribes nigrum L.)cultivars grown in the Northeast of China were selected,including 12 cultivars introduced from Russia,10 from Poland and the rest from local areas.The physicochemical properties and amino acid compositions of these varieties were studied,and the geographical origins of blackcurrants were tracked by multivariate statistical analysis.A total of 23 amino acids were detected in all cultivars,which were rich in glutamine,glutamate,aspartate,asparagine,α-alanine,γ-aminobutyric acid,valine and serine.The content of the total amino acids in these cultivars was from 31.21 mg•100 g-1 to 319.40 mg•100 g-1.Stepwise linear discriminant analysis(SLDA)was introduced to perform satisfactory categorization for blackcurrant cultivars,which achieved a success rate of 88.9%for the identification of geographical origins.These results suggested that the compositions of amino acids in blackcurrants could effectively predict geographical origins.
基金Support by the National Natural Science Foundation of China(31371650,31071440)Northeast Agricultural University Innovation Foundation For Postgraduates(yjscx4042)。
文摘The effects of the deficiency of the allergenicα-subunit on soybean amino acid(AA)composition were studied using the cultivar Dongnong 47(DN47)as a genetic background.The near-isogenic line(NIL)NIL-DN47-Δα of DN47,with an introgression of theα-null trait allele from the high protein donor parent RiB,was created by marker assisted background selection and used to investigate the AA content and nutritional quality.The contents of crude protein,the total AAs,the total essential amino acids(EAAs)and sulfur-containing(Met and Cys)AAs increased by 4.11%,4.16%,5.20% and 11.96%,respectively in NIL-DN47-Δα compared with DN47.Analyses of the total EAAs(TEAAs)and the EAA index(EAAI)revealed that both parameters in NIL-DN47-Δα were higher than those in DN47.The null-allele of theα-subunit positively affected the AA scores.The quantitative changes in free AAs(FAAs)in the developing seeds of NIL-DN47-Δα and DN47 were compared as of 15 days after flowering(DAF)until maturity.The results showed that the total FAA content in NIL-DN47-Δα was significantly higher than that in the DN47 throughout the late maturation stage(40-60 DAF)of seeds.The high concentration of the FAAs in cgy-2 mutant seeds was a consequence of the high rates of synthesis and/or accumulation of individual FAAs during seed maturation where 25 DAF was an important turning point in the accumulation of the FAAs.The FAA contents of single soybeanα-null,double(α+α′)and triple(α+α′+group I)-null mutant combination lines were investigated.In all of these combinations,introduction of the cgy-2 gene invariably raised the FAA content of mature seeds above that of the DN47.In summary,the enhanced protein quality in cgy-2 mutants resulted from several factors.(1)There was a general increase in the contents of most AAs and FAAs in NIL-DN47-Δα.(2)The induced synthesis of free Arg contributed effectively to the high FAAs of various storage-protein-deficiency mutants.For example,in the S2(null α,group I),the free Arg content was seven times as much as that of DN47,accounting for more than half of the total FAA content in the seed.(3)The increase of sulfur-containing AAs in theα-null type NIL mainly resulted from elevated Met content.These data suggested that the cgy-2 mutation might improve the protein quality of soybean seeds and that lacked of the allergenicα-subunit resulted in increased the FAA content.
文摘HPLC-MS/MS methods were developed to determine 19 kinds of free amino acids in human serum. API 4000 and Quattro Ultima HPLC-MS/MS systems were used in this study. The established method proved to be fast and specific.It can be applied to determine 19 kinds of amino acids simultaneously and also can be used in the disease screening studies associated with amino acids disorders.
基金Supported by Hainan Provincial Natural Science Foundation of China(322MS134)。
文摘This study aimed to investigate the effects of dietary guanidinoacetic acid on growth performance,meat quality,antioxidant activity,and antioxidant-related gene expression in ducks.Total 48042-day-old female ducks were randomly divided into four groups with six replicates and 20 ducks per replicate and fed the basal diet to the control group.The experimental groups were fed the basal diet with 400,600 and 800 mg·kg^(-1) guanidinoacetic acid,respectively.The trial lasted 48 days.Compared with the control group,(1)the body weight at 90 days and average daily gain were increased(P<0.05),the feed conservation ratio was decreased(P<0.05);(2)the dressing percentage and breast muscle percentage were increased(P<0.05);(3)the total amino acid content,polyunsaturated fatty acids to monounsaturated fatty acids ratio were increased(P<0.05)in breast and thigh muscles;(4)activities of superoxide dismutase,catalase and glutathione peroxidase enzyme were increased(P<0.05)in thigh muscles;(5)the relative expressions of superoxide dismutase 1,glutathione peroxidase 1,and catalase were significantly increased(P<0.05)in the liver.In this study,the optimum dosage of 600 mg·kg^(-1) guanidinoacetic acid improved the growth performance,meat quality,antioxidant activity,and antioxidant-related gene expression in ducks.
基金Supported by the National Natural Science Funds (31201397)Science Fund for Distinguished Young Scholars Program for Changjiang Scholars and Innovative Research Team in University (IRT0959)Doctor Start Fund of Northeast Agricultural University (2010RCB59)
文摘Growth and osmotic response of Lactobacillus bulgaricus ATCC 11842 under hyperosmotic constraint were investigated in a chemically defined medium （CDM） and MRS medium. NaCl could inhibit the growth of L. bulgaricus which decreased with increasing NaCl concentration. In the MRS, NaCl of 1.0 mol·L-1 was the biggest salt stress concentration; in the CDM, 0.8 mol·L-1 was the biggest inhibition concentration. In contrast to what was observed in other lactic acid bacteria, proline, glycine betaine and related molecules were unable to relieve inhibition of growth of L. bulgaricus under osmotic constraint. This was correlated to the absence of sequences homologous to the genes coding for glycine-betaine and/or proline transporters described in Lactococcus lactis and Bacillus subtilis. The amino acid aspartate and alanine were proved to be osmoprotective under NaCl stress. Addition of peptone （0.25% w/v） in the presence of salt led to a stimulation of the growth, as the decrease of the lag time and generation time, and the final biomass increased from 0.31 to 0.64.
基金Project(2017210101002066)supported by the Crosswise Project of Liaoning province,China
文摘The synergistic inhibition effect of CeCl3(Ce)and serine(Ser)on the corrosion of carbon steel in a 3%NaCl solution was investigated by electrochemical methods and surface analysis.The results showed that both CeCl3 and Ser,when used alone,had limited inhibition effect toward carbon steel corrosion in the 3%NaCl solution.In contrast,the combination of CeCl3 with Ser produced a strong synergistic effect on the corrosion inhibition behavior of carbon steel,improving the inhibition efficiency significantly.The polarization curves showed that the mixture of CeCl3 and Ser acts as a cationic-type inhibitor.Scanning electron microscopy and Fourier transform infrared spectroscopy showed that the synergistic inhibition effect was due to complex formation between the cerium ions and amino acid molecules.
基金Project(21107032) supported by the National Natural Science Foundation of China Projects(Y406469, Y4110606) supported by the Natural Science Foundation of Zhejiang Province, China+1 种基金Projects(2008AY2018, 2011AY1048-5, 2011AY1030) supported by the Science Foundation of Jiaxing Science and Technology Bureau,ChinaProject(2009C21003) supported by the Science and Technology Department of Zhejiang Province,China
文摘D,L-lactide was prepared from D,L-lactic acid by means of polymerization and depolymerization at low vacuum level.Morpholine-2,5-dione(MD) was synthesized from the cyclization of chloroacetyl glycine which was made from chloroacetyl chloride and glycine in the basic condition.A novel copolymer(PLAMD) with D,L-lactide(D,L-LA) and morpholine-2,5-dione(MD) was synthesized using stannous octoate as initiator,and characterized with FT-IR and 1HNMR.The biocompatibility of PLAMD and PLA was investigated by MTT and microscope.The results show that amino acid is introduced into PDLLA main chain.PLAMD has better cell affinity than PLA,so it is a promising biomaterial.
