Abstract:The amino acid compositions,sequences,possible active sites and antioxidation mechanisms of antioxidative peptides were summarized in this paper.The research methods of antioxidative peptide structure-activity relationship were also introduced.

Abstract:In this study,ethanol extract and dregs were prepared by ethanol extracting of Brazilian green propolis.Then ultrasonic assistant extraction technology was used to obtain volatile components from raw material,PEES and DPEES.The chemical components were separated and identified by gas chromatography-mass spectrometry(GC-MS).14 active ingredients were identified from Brazilian propolis volatile components and the major components were aromatic compound and ene terpenoids,14 and 11 active ingredients were identified from PEES and DPEES volatile components,the major components were ene terpenoids and organic acid esters,but the main volatile substances in the PEES also contains alkanes.The results revealed that there are some same volatile components as well as some different ones among raw material PEES and DPEES,but their contents is obviously different,meanwhile some active ingredients can transformed between each other.

Abstract:Site-directed mutagenesises had been done in this work with the consideration of increasing the thermostability of a family 11 xylanase(AoXyn11A) from Aspergillus oryzae.The mutant,AoXyn11AM,was obtained by introducing a disulfide bridge into the N-terminal region of AoXyn11A after N-terminal amino acid homology alignment of AoXyn11A with a thermostable family 11 xylanase,EvXyn11TS.The thermostability of the wild-type enzyme and mutant were analyzed by homology modeling,and assessed by molecular dynamics(MD) simulations.The genes,AoXyn11A and AoXyn11AM,were expressed in Pichia pastoris GS115,respectively.And the effects of temperatures on the thermostability of the expressed AoXyn11A and AoXyn11AMwere analyzed.The results showed the optimal temperature of AoXyn11AMwas raised to 60 ℃ from 55 ℃ of AoXyn11A;after incubated at 50 ℃ and 55 ℃ for 30 min,respectively,the mutant retained 94% and 45% of its original activity while the wild-type enzyme retained 62.5% and 1.4% of its original activity.The mutant not only preserved the major excellent properties of the wild-type enzyme,but also enhanced the thermostability which is potentially useful in industrial applications.

Abstract:In order to obtain high-quality dried mushroom efficiently,this paper investigated the impact of infrared drying on the drying characteristics of shiitake mushrooms,and compared with hot air drying methods,analysis of the impact of two different drying methods on the products quality of dried shiitake mushroom.The results showed that Pre-drying,Gill-up position have higher dryi ng rate than cap-up position;As the temperature increases,the irradiation distance decreases,the loading coefficient decreases,the wind velocity increases,the time required for drying is gradually reduced.The products sensory and chemical quality dried by infrared is superior to hot air.

Abstract:A cDNA gene(AusfaeA),which encodes a feruloyl esterase(FAE) A from Aspergillus usamii E001(abbreviated to AusFaeA),was amplified by RT-PCR.The expressing plasmid pPIC9K-AusfaeA was constructed and linearized with SacⅠ,followed by transforming it into Pichia pastoris GS115 by eletroporation.The recombinant P.pastoris GS115/AusfaeA was screened by G418 and then was induced with methanol to express reAusFaeA.The purified reAusFaeA showed one single band on SDS-PAGE with an apparent molecular weight of 36.0 kDa.The feruloyl esterase activity of the reAusFaeA against methyl ferulate(MFA) reached 29.4 U/mg determined by HPLC.Its optimal temperature and pH were 45 ℃ and 5.0,respectively.It was stable at a temperature of 45 ℃ or below,and at a pH range of 4.0 ~6.0.Its enzymatic acvitity was not signficantly affected by an array of tested metal ions.This indicated that the AusfaeA was successfully expressed in P.pastoris and the excellent properties of the reAusFaeA make it a potential candidate for applications in industrial processes.

Abstract:In this paper,the flavor changes of marinated fish with different desalting methods were mainly investigated based on the sensory evaluation and determination of texture.The different desalting method were clear water immersion,desalting agent,pricking,oscillation and vacuum reverse infiltration The experiment results showed that the different ways of desalination could improve the desalting rate and also were beneficial to keep the nutrition of fish;however they all had negative effects on the fish flavor in a way.The oscillation and the mixed way of "adding 1.5% trehalose+pricking+oscillation" were effective desalination treatment based on the flavor of sensory evaluation.

Abstract:In this study,we compared the TBA,DPPH clearance rate and polyphenols of beer filtrated though 0.45 μm membrane with that pasteurized at 60 ℃ for 30 minutes,analyzing the difference between the two beers which adopted different post-treatment technology.During the pasteurization,the staling compounds generate and the content of aldehydes increases by 30.85%.At the same time,beer aging deepens and TBA increases by 1.67% during pasteurization in real production.Filtration can intercept and adsorb endogenous anti-oxidants in draft beer.So the content of polyphenols decreases by 9.149%、4.439%、6.022%respectively.The DPPH clearance rate decreases by 3.24% during filtration in real production.The aging level of fresh draft beer is lower than pasteurized beer,but it has a higher aging rate due to less endogenous anti-oxidants.As a result,the aging level of draft beer will be deeper than pasteurized beer during storage.

Abstract:The effects of isolated soybean protein,chitosan,sodium alginate,sodium chloride and alum on the quality of ginkgo starch noodles(GBSN) were investigated by differential scanning calorimeter,rapid viscosity analyzer and texture analyzer.Results showed that sodium alginate and alum influenced the quality of GBSN,and the quality of GBSN added with 0.50% sodium alginate or 0.75% alum was best.Compared with commercial mung bean starch noodles(MBSN),the quality of GBSN added with sodium alginate or alum was close to that of commercial MBSN.GBSN added with sodium alginate and alum had similar quality,suggesting that sodium alginate could replace alum as an additive of GBSN.

Abstract:In order to explore the manufacturing suitability for Zijuan tea,the aroma components of Zijuan black tea were extracted by fully automated HS-SPME,and were identified by GC-MS.Then comparison of the aromatic components and contents between Dianhong tea was made.The results showed that 83 kinds of aroma components were identified in Zijuan black tea and 82 kinds in Dianhong tea,alcohol was the major aromatic components in these two kinds of tea,representing 44.42% and 44.99% of the total peak area respectively.The major aromatic compounds of Zijuan black tea were linalool,linalool oxide,phytol,caffeine,6,10,14-trimethyl-2-pentadecanone,hexadecanoic acid and geraniol,respectively,while the major aromatic compounds of Dianhong tea were linalool,hexadecanoic acid,linalool oxide,phytol,geraniol,caffeine and methyl salicylate.The aromatic components in these two kinds of tea were found very similar and 77 of them were identical,the contents of aldehydes,esters and acids compounds in Zijuan black tea were lower than that in Dianhong tea,but the contents of other compounds are higher than Dianhong tea.

Abstract:As to a large number of proteins from discharge wastewater of Surimi processing enterprises,A single factor experiment about the dosage、temperature、 time、 pH can be operated by selecting a flocculant.Then Design-Expert software is a experimental containing four factors and three levels.The result shows that:the optimal recovery process is adding the amount of ferric chloride 0.13 g/L,the flocculation temperature is 18.44 ℃,the time is 5 h,the pH is 5.44.At this point,recovery rate achieves to 89.94%.The method has the features with a high protein recoveries,the safety and health of the recovery protein,easy operation,low cost,etc.

Abstract:An immunoaffinity column(IAC)for melamine with high column capacity was prepared in this study.Based on a monoclonal antibody against melamine,a silanization approach was used to coat antibody as ligands.The resulting products were packed in columns.Series concentration of melamine was loaded on the columns to evaluate column’s performances.UV spectrum and liquid chromatography tandem mass spectrum(LC-MS) were used to test the melamine level of eluents from columns.The mean load capacity of the prepared columns was 16.47 μg per column.Under the optimized conditions(washing condition,loading buffer,eluent condition and regeneration buffer),the proposed IAC has a condensation coefficient of 66 folds and it could be used over 5 times with the recovery higher than 60%.

Abstract:Endoglucanase cooperates with cellobihydrolase and β-1,4-glucosidase to translate cellulose to glucose completely.Now lots of researchers found that low enzymatic activity and high cost are the two main problems that restrict the industrial applications for cellulase.In order to enhance the enzymatic activity of the neutral endoglucanase activity,error-prone PCR strategy was conducted on Bacillus subtilis C-36 endoglucanase gene.The mutant F-10 with endoglucanase activity improved 4.2 folds respectively were obtained.The sequence of F-10 showed five nucleotides substitutions to two mutated amino acids.SDS-PAGE showed genes are correctly expression.Enzymatic properties of mutant F-10 showed that:The optimal temperature and pH value changed compared with the original enzyme,it’s optimal temperature and pH is 45 ℃ and 5.6,respectively.The enzyme maintained over 80% of the original enzymatic activity after incubated from pH 4.5 to 10.0 at 50 ℃ for 30 min and the enzyme maintained over 80% of the original enzymatic activity in 60~75℃,but when temperature upon 75 ℃,then enzymatic activity decreased sharply.

Abstract:In order to establish two-dimensional electrophoresis technology system of total proteins of Pteridium aquilinum,2-DE maps was compared with protein extraction method,loading amount and pH ranges of IPG strips The results showed that phenol extraction protocol combined with TCA/ acetone was more favorable for total protein extraction from fresh Pteridium aquilinum.A high quality 2-DE map with more protein spots,better dispersion,clearer background and higher protein point resolution were acquired by using the following optimized parameters:loading 1200μg protein sample on 17cm IPG strip with pH 5-8,and finally detecting proteins with Coomassie brilliant blue G250 staining.Under above experimental conditions,the total number of protein spots is 719,this experimental results provides a basis for further study of post-harvested Pteridium aquilinum proteomics.

Abstract:In this study,the isolation,purification and structural analysis of Chestnut Polysaccharides(CPS) were performed,and then the anti-fatigue effects were investigated.Gas chromatography of CPS-X indicates that the molar ratio of monosaccharide constituents of CPS-a is glucose∶mannose∶xylose∶arabinose=7.1∶6.2∶5.1∶4.1,and for CPS-b which is glucose∶fructose∶mannose∶ xylose ∶arabinose =7.1 ∶6.4 ∶6.2 ∶5.0 ∶4.1.Infrared spectroscopy analysis shows that both CPS-a and CPS-b have the pyranoid ring,and CPS-a may be a furanose derivative,furthermore,the sugar chain of CPS-b,which may be a sulfated polysaccharide,contains both α-and β-glycosidic bond.The anti-fatigue effects of CPS show that CPS in three different doses all significantly increase exercise tolerance,decrease the content of serum BUN and LAC and increase the content of muscle glycogen and hepatic glycogen after swimming.Thus,we conclude that CPS have an excellent effect of anti-fatigue and the optimum does is 200mg/kg.d,and the high doeses shows no superiority.

Abstract:A bacterial strain P10 with better phosphorus removal performance was isolated from the excess sludge in a sedimentation basin of a laboratory scale A/O reactor with stable performance.The optimum pH of growth and initial phosphorus removal for the bacterium are 6.5 and 6.0,respectively.The optimum temperature for cell growth and phosphorus removal are at 30 ℃.Ferrous,manganese and copper ions can stimulate bacterial growth.Moreover,ferrous and manganese ions also promote the phosphorus removal.The addition of ferrous ions could increase the cell concentration by 8.1% and the phosphorus removal amount by 46.0%.The highest removal rate could be reached(up to 11.23 mg/(g·h)) with the phosphorus in form of dipotassium hydrogen phosphate.

Abstract:A rapid detection method for dapsone residue in animal-originated food was established based on indirect competitive enzyme-linked immunosorbent assay.The results showed that the 50% inhibitory concentration(IC50) of the method was 0.369 μg/L.The detection limit for chicken and pork was 0.2 μg/kg,for egg and honey was 2 μg/kg,and for milk was 0.6 μg/L.Sample recoveries were 78.2%~104.0%,and the coefficients of variation were 5.2%~13.5%.Results of the method were in accordance with those of liquid chromatography-tandem mass spectrometry(LC-MS/ MS).This method has the advantage of being sensitive and accurate,and suitable for the rapid detection of dapsone residue in animal-originated food.