Abstract:Based on the lipase sequences from 34 kinds of strain,the relation between amino acids and dipeptides with the optimum temperature were built by a stepwise regression method.The results showed that the positively correlated amino acid was Y,while the negatively correlated ones were I,S and K,and that the positive dipeptides were IR,KS,NY,SA,ST,YR,whereas the negative ones were DK,DY,IS,KA,WS,YS,QI.Through analysis of position information of the related dipeptides in thermophilic and mesophilic lipases,it was found that most positive dipeptides were sited in the α-helix and on the surface of lipases,whereas most negative ones were located in the β-strand or coil,which distributed in buried regions of lipases and often existed in the N or C terminus of lipase chains.

Abstract:The aim of this manuscript was to improve the qualitiy of mayonnaise through supplement of alginate,for this,the effect of alginate content on the rheological of mayonnaise were analysis.All mayonnaises prepared in this study exhibited shear thinning behavior,thixotropy and following the Herschel–Bulkley model.The viscosity(within 4~25℃) followed an Arrhenius temperature dependence and and the activation energy was determined,the addition of alginate also affected apparent viscosity of mayonnaise.Viscoelastic properties of mayonnaise samples were characterized using dynamic oscillatory shear test and it was observed that mayonnaises exhibited weak gel-like properties by small strain oscillatory measurements.According to those results,the addition of 2.0% alginate significantly increased the rheological stability of mayonnaise.

Abstract:Purified polygalacturonase(PG) was chemically modified with water soluble chitosan oligosaccharide(COS) as modifier.The optimum modification conditions were determined by the single factor tests and orthogonal tests and listed as follows: purified PG 80 mg,pH 4.0,temperature 3 ℃,reaction time 12 h,COS content 150mg.Under the optimum conditions,The specific activity of the modified PG was 340.10 U/mg protein,higher 153.42% than that of the unmodified PG.

Abstract:In this study,the antioxidation and deoxidize activity of blueberry polyphenol was studied and compared with VC using the hydrogen peroxide,hydroxyl radical,superoxide radical,nitrite system as index.Results demonstrated that the blueberry polyphenol exhibited different antioxidation activities in these radicals.The scavenging activity to nitrite system and hydroxyl radical was lower,but the hydrogen peroxide system was higher than that of VC.Furthermore,,scavenging activities to deoxidize activity and superoxide radical system were equal to VC.

Abstract:In this mansucript,the milk from Xinong Saanen goat and Holstein cattle was used as the research model to investigate the volatile free fatty acid composition and to elucidate the molecular mechanism.Volatile free fatty acids were extracted by solid-phase microextraction(SPME),were analyzed by gas chromatograph combination with mass spectrophotometer(GC-MS).The AT-MT gene sequence of fatty acid synthase from Xinong Saanen goat was cloned,and the AA sequence and protein secondary structure distribution were compared with that of Holstein cattle.The results showed that n-Decanoic acid was the main effect flavor component(40.89%) in Xinong Saanen goat,there were significant differences in AA sequence and protein secondary structure distribution between Xinong Saanen goat and the cattle.It demonstrated that fat enzyme gene of synthesis and metabolism was responsible for goaty flavor,and breeding methods of tradition and molecular could be effective ways to improve goat milk quality.

Abstract:The antimicrobial activity,minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) of essential oil in Mentha piperita and Mentha cardiaca were determined in this study.Furthermore,the polyphenol content and antioxidant activity of solid residues in two mints were also investigated.The results demonstrated that the two essential oils exhibited inhibition effect on E.coli,Staphylococcus aureus,Salmonella typhimurium and Listeria monocytogenes,however,without inhibitory effect was observed in the case of Salmonella enteritidis and Aspergillus niger.The antimicrobial ability of peppermint essential oil was stronger than Scotch spearmint essential oils.Besides,the polyphenol content in residues of peppermint was significantly decreased,but that in Scotch spearmint had no significant reduction.The residues of two mints had stronger ability of scavenging DPPH after water distillation,but the antioxidant ability in FRAP assay reduced significantly.

Abstract:The color conserves and flavor improvement of oyster mushroom soft packaged products were studied in this manuscript.The optimum method of color conserve was 0.07% ascorbic acid and 0.1% citric acid.The single factor experiment and L9(34)orthogonal experiment were carried out to optimize the process conditions.And the best formula assessed by sensory evaluation together with texture measurement and GC-MS analysis were as follows: edible gums 1.8%,mixed ratio(Carrageenan:Konjac Gum) 3∶1,meat powder 1% and mushroom essence 0.2%.

Abstract:In this manuscript,fatty acid composition and Vitamin E content of Camellia oleifera oil were analyzed by Gas Chromatograph and HPLC respectively.The results show that: the primary crushing oil and refining oil are both contain 4 kinds of fatty acids mainly,which are palmic acid(7.68% and 8.92%),stearic acid(1.66% and 1.78%),oleic acid(82.90% and 81.90%),linoleic acid(7.17% and 7.22%);the linear range of VE was 0.5~2.5 μg(R2=0.999 3),and the mean recovery was 98.05%,RSD=0.75%(n=5).The VE content of primary crushing oil was 207mg/kg,which declined to 107.07mg/kg in refining oil.The chromatographic methods established in this text are fast,convenient and reliable.

Abstract:Hydroxypropyl-β-cyclodextrin(HP-β-CD),containing special hydrophobic cavity,was used to include rose flavor.In this study,the average size was as major index and PDI and ζ potentia as t two auxiliary indexes to choose the optimum process parameters.The optimum conditions were determined by single-factor and he Box-Behnken design of response surface methodology and listed as follows: reaction time of 4h,electromagnetic stirring speed of 1000rpm,reaction pH of 8,the mass ratio of external to internal capsule of 1.69,the emulsifier of Tween-20,the mass ratio of emulsifier to flavor of 3.13,solid contents of 1.5%.under the optimum conditions,the average size is 72.8nm,the PDI is 0.127,and the ζ potential is-12.6mv.It also has a spherical shape by the transmission electron microscopy.

Abstract:Absorption on macroporous resin was studied as a method to separate Ageratum conyzoides Flowers blue pigment in this manuscript.The optimum conditions for absorption and desorption of Ageratum conyzoides Flowers blue pigment was determined and listed as follows: D301 with the upper adsorption rate at 90.0mg/g,the stability and the little balance time was suitable for absorbing and separating Ageratum conyzoides Flowers blue pigment.The optimum condition was at the flow rate of 2.0mL/min,concentration of 0.2 mg/mL and the temperature of 20 ℃.D301 was washed with HCl of 2.0mol/L,and the washout rate achieved at 96.08%.

Abstract:The target of this manuscript was to investigate the effect of vacuum freeze drying,spray drying,vacuum drying and hot air drying on the quality of chitooligosaccharides.For this,Chitooligosaccharides powder was made by different drying methods.Physical properties,contents of reducing sugar,total sugar and free amino groups,antioxidative activity were determined.It was found that vacuum freeze-dried product possessed the highest contents of reducing sugar,total sugar and free amino groups,and exhibited the best hydroxyl free radical scavenging capacity,color,and solubility.The quality of spray-dried product was almost the same as that of vacuum freeze-dried product.The tested indices of vacuum dried product were better than that of hot air dried but less than vacuum freeze dried and spray dried product except its superoxide anion radical scavenging activity.Hot air drying produced the poorest chitooligosaccharides powder which possessed dark color,poor solubility,low content of free amino groups,reducing and total sugar.Among of them,spray drying is more suitable for the actual industrial production.

Abstract:The determination methods for three kinds of phthalic acid esters in leaching solution of plastic food packaging using Single-drop microextraction(SDME) couple with gas chromatography-hydrogen flame ionization detector(GC-FID) was developed in this study.The optimum conditions for the assay were detected and listed as follows: with 1.4 μL xylene as the organic extractant,extraction time 20 min,the extraction temperature 40℃,stiring speed 200 rpm.Under the optimum conditions,the DMP,DEP and DBP had the linear range of 0.1-100 μg/mL and the detection limits were 0.01 μg/mL.The actual sample recovery was 97-113.9% d.This method is proved to be a simple,fast and low cost approach for determination of trace phthalic acid esters in leaching solution of plastic food packaging.

Abstract:Polysaccharides in Nostoc commune Vach.was extracted by water extraction and ethanol precipitation in this study.and further purification to investigated the antioxidant and antimicrobial activities.The results showed that the polysaccharides from N.commune could significantly decrease the OH and DPPH free radicals and the rate could arrived at 71.53% and 66.35% respectively.However,the Polysaccharides had little scavenging effect on superoxide anion radicals and nitrite.Furthermore,it was found that the polysaccharides could inhibit the growth of Bacillus subtilis and Escherichia coli.The minimal inhibitory concentrations(MIC) varied from 125 to 250μg/mL.No obvious inhibitory effect on Staphylosocus aureus was observed.

Abstract:The object of this study was to elucidate the effect of Cabbage(thiocyanate) and Beans(flavonoids) extract on the food utilization,liver function and kidney function of rat.For this,The rats divided into different groups according the design of experiment and feeding by different dosage of Cabbage(thiocyanate) and Beans(flavonoids) extract,and then the blood and tissue were extracted after 30 days.It was found that there are without obvious effect on food intake.Compared with the normal control group,single dose of cabbages and beans groups,the joint low-dose group and the joint high-dose group in rats liver coefficient were significantly increased(P<0.05、P<0.01、P<0.05),however,there are no significant effect on kidney coefficient.Compared with the normal control group,each experiment groups ALT/AST are decreased significantly(P<0.01).Compared with the normal control group,it is more significant(P<0.01)in the cabbage group,bean group,middle-dose group(experiment group Ⅱ),high-dose group(experiment group Ⅲ) in rats serum total bilirubin.Compared with the normal control group,single dose of beans groups,the joint low-dose group(experiment group I),the middle-dose group(experiment group II),the joint high-dose group(experiment group III) in rats blood urea nitrogen(BUN) were significantly increased(P<0.05、P<0.01、P<0.05、P<0.05).From the above results,we can draw the conclusion that with thiocyanate,flavonoids increase in food intake,the liver and kidney function were injuries on the body,showing more pronounced in the liver.Also suggested that blindly added thiocyanate,flavonoids will increase the burden of liver and kidney,the potential for thyroid history(hereditary familial,iodine deficiency areas,etc.) people in particular,attention should be paid.

Abstract:In this study,the effect of plant growth regulators on the taxol biosynthesis by Metarhizium anisopliae Tax-27 was investigated.The results showed that the titer of taxol was 670.49 μg/L,838.11μg/L,942.57μg/L,455.72 μg/L,450.48 μg/L when 4 mg/L gibberellin(GA3),60μmol/L methyl jasmonate(MeJA),25mg/L chlormequat chloride(CCC),4 mg/L 6-benzylaminopurine(6-BA),and 4 mg/L 1-naphthlcetic acid(NAA) was feed to the fermentation broth,respectively..However,the addition of GA3,MeJA,CCC inhibited the mycelial growth of M.anisopliae Tax-27,on the other hand,the addition of 6-BA and NAA significance increased the mycelia growth.

Abstract:In this study,mice BALB/C were immunized by melamine-BSA and anti-melamine monoclonal antibody(McAb) was prepared by using hybridoma technique.The ELISA titers of ascite was exceeded 50,0000.Subtype of the McAb was IgG1 and the affinity constant was 3.21 109 L/mol.The cross-reactivity with Cyanuric acid,cyanurodiamide and ammelide was 30%,93% and 46% respectively.The monoclonal antibody can be used for fast determination of melamine substances.

Abstract:The objective of this study is to investigate the protective effect of purple sweet potato on liver injury mice which caused by CCl4 and BCG+LPS.For this,a total of 100 male ICR mice were randomized divided into 2 big groups according to the injury methods and then equally randomized into 5 small groups: normal control group,bifendate control group,liver injury control group,low and high dose of purple sweet potato group.Those mice feeding them with corresponded feedstuff.Observed ALT,AST level in the blood and MDA,GSH level in the liver after 12 hours treatment,then calculated the liver and spleen index in the mice.Results: The liver,spleen index,alanine aminotransferase(ALT),aspartate aminotransferase(AST) level in the blood and malondialdehyde(MDA),glutathione(GSH) level in the liver of mice in the treat control groups were significantly different from that in the liver injury control group(P<0.05),and the liver,spleen index level are significantly correlated with ALT,AST in the blood and MDA,GSH in the liver(P<0.05).Conclusion The purple sweet potato exhibited a significant regulated effect on both CCl4 and BCG+LPS induced the liver injury in mice,.The mechanism may be related to reducing enzyme,the level of lipid peroxidation,and preventing liver cell necrosis.

Abstract:Phytosterol fatty acid esters can be synthesized by direct esterification of fatty acid with phytosterol in the presence of acidic/basic catalysts.Micelle-catalysts were used in the esterification reaction for preparation of phytosterol esters in good yields.The experimental results showed that cupric dodecyl sulfate exhibit excellent activity in this reaction,which can be recovered after the reactions and reused.The optimum reaction conditions were determined and listed as follows: molar ratio of fatty acid to phytosterols 1.2∶1and the amount of catalyst 1.0 mol % at 110 ℃ for 4 h.With this optimum coditions,the esterification rate of phytosterol esters reached at 80.7~86.4 %.

Abstract:The aim of this manuscript was to investigated the effects of process paraments on the extracted rate of the prickly ash by supercritical-CO2 fluid.Those parameters include extracting pressure,time,temperature,inventory rating,and dosage.The optimum process parameters were determined by single factor and orthogonal experiment and listed as follows: pressure 33-35 MPa,temperature 50 ℃,time 3.5 h,CO2 flow rate 15-25 L/h,entrainer dosage 15%.

Abstract:The aim of this study was to analyze the source of AFB1 and degradation of AFB1by various stages during the production process of fermented soy sauce.The water content,water activity,amino nitrogen,total acid,microbes(the number of total colony,fungi,yeast and toxigenic fungi) and AFB1 were detected at different stages.Results reveal that 50% of AFB1 was caused by raw materials and another 50% was produced by toxigenic fungi at early fermentation stage.Steaming,making koji,fermentation and leaching can reduce some AFB1,however,52.04% of AFB1 can be migrated to soy sauce from pastes after soaking.Therefore,we need to take appropriate measures to control the AFB1 contamination in soy sauce.

Abstract:Morphological aspects,physiological and biochemical characters and 16 S rRNA sequence were utilized to identify the bacterium isolated from the decayed cyanobacteria in this study,and liquid state fermentation was utilized to evaluate the effect of carbon and nitrogen resources on its protease production.The data showed that the bacterium isolated was belonged to the genus Serratia designated as Serratia marcescens SYBC YH.The optimal carbon resource was fructose,glucose,feather powder,or powder of corn seed.The optimal nitrogen resource was corn steep powder,yeast extract or beef extract.The strain could produce protease by liquid state fermentation with cyanobacteria as sole nitrogen resource to produce organic solvent tolerant protease.The optimal catalytic temperature and pH was 40℃ and 7.0 respectively.

Abstract:In this study,a novel strain MBL13 was isolated from screened the soil in the animal bone factories through screening methods.It was found that the strain could secreted 36.80±1.93 U/mL collagenase in fermentation broth.Furthermore,the strain was identified as Bacillus cereus through morphology,physiology biochemistry characteristic,16S rDNA sequencing and Fourier Transform Infrared determination.the collagenase secreted from MBL13 exhibited higher hydrolysis capacity on bovine bone collagen than that of type I collagenase(United States).It was believed that the collagenase from MBL13 has the specific restriction sites due to the bands of peptides generated after digestion was not continuous.

Abstract:The supply of oxygen,nitrogen sources and different initial glucose concentrations were studied for L-Lysine fermentation in shaking culture,and then,L-lysine fermentation was performed in 7 L fermentor.L-lysine·HCl and conversion efficiency reached 161 g/L and 58.3% respectively in 7 L fermentor after 64 h.

Abstract:Effect of surfactant on lipase production of Fusarium sp.was investigated in this manuscript.The results showed that lipase activity was achieved at the maximum value in adding soapberry extraction,which indicated that soapberry extraction is the best surfactant,and lipase activity was the highest when the liquid-to-solid ratio is 6∶1(mL∶g).Lipase extraction by Aqueous Two-phase System following the precipitation of the crude enzymes by ammonium sulfate was also studied.The results indicated that the highest of decontamination factor F and extraction rate Sf achieved when the conditions of extraction showed as follows:the molecular weight of PEG was 4000,the concentration of PEG(M 4000)was 30 g/dL,and the concentration of NaH2PO4 was 20 g/dL.At last,the lipase was purified 7.92 folds and the recovery was 48.30% by Aqueous Two-phase Systems.

Abstract:Serpin was amplified from the genome of Bifidobacterium longum WBL001.Recombinant plasmid pBX2-serpin was constructed and expressed in Escherichia coli for Serpin production.The recombinant protein was purified and used as antigen for mice immunization.Antiserum was purified specifically by Serpin-coupled magnetic beads.The antibody eluting was optimized by using different eluents.Serpin-like protein was screened out from 11 Bifidobacteria strains by colony immunoblotting.The result indicated that 1 mol/L NaOH is the best fluent for antibody elution from magnetic beads(about 50% recovery).Non-specific reactions of antiserum with lactic acid bacterium and pathogens were eliminated after purification.Serpin-like protein had been found in B.infantis WBAN07 from 11 Bifidobacteria strains by colony immunoblotting.

Abstract:A thermostable α-glucosidase gene aglA(TM1834) from a hyperthermophile bacterium,Thermotoga maritima,was expressed in Escherichia coli JM109 using the new heat-shock expression vector pHsh.The recombinant α-glucosidase aglA was purified by heat treatment,ion exchange chromatography,and hydrophobic chromatography,and had a molecular weight of 55 kDa as indicated by SDS-PAGE analysis.The optimum pH and temperature for this enzyme was pH 7.5 and 90 ℃,respectively.More than 50% was detected at pH values between 6.5 and 8.5 and temperatures between 65 ℃ and 100 ℃.The maximal aglA activity was observed in the presence of cofactor NAD+,Mn2+,and DTT.

Abstract:In this study,total RNA,instead of genome DNA,was extracted from pressurized cooked ham and then performed with RT-PCR-denaturing gradient gel electrophoresis(DGGE) analysis to explore whether this molecular method was feasible to reveal the active species in the samples.Sliced vacuum-packed cooked ham were high pressure treated at 400 MPa and 600 MPa for 10 min at room temperature(22 ℃) and then stored at 4 ℃.Directly RNA extraction from meat samples and RT-PCR-DGGE analysis was performed at storage time 1,30,60,90 days(after HPP).Results showed that the major spoilage bacteria in the samples were largely inactivated by HPP and that higher level of pressure leaded to better effect.The microbial diversity of HPP samples during the whole refrigerated storage was extremely simple.Only Weissella viridescens survived the HPP of 600 MPa for 10 min at 22 ℃ and Weissella viridescens coupled with Leuconostoc mesenteroides survived the HPP of 400 MPa for 10 min at 22 ℃.The RNA-based DGGE method adopted is shown to be an efficient tool for the detection of active bacteria in pressurized cooked ham.

Abstract:The objective of this study was tocompare the efficiency of two elute strategies in biopanning of single-domain heavy-chain antibody(HCAbs) phage display library against low molecular hapten,Aflatoxin B1(AFB1).For this,the artificial antigen AFB1-BSA and AFB1-OVA were used as ligand to screen the binding phages from an Alpaca non-immune library by antigen-coated solid phase selection.The binding phages were directly eluted with Gly-HCl or competitively eluted with AFB1 solution.The eluants were tittered separately.It was found that the recovery rate of Gly-HCl is 5 to 10 times higher than that of competition method.Twenty colons randomly picked from each eluant were characterized by phage-ELISA.Eight positive colons were isolated from the eluant by the competition method;however,no positive colons were isolated by Gly-HCl method.The sequencing data show that all the colons are encoding single-domain HCAbs.

Abstract:Using trans-anethole as the sole carbon source,a strain WGB30 was screened from 320 isolates,and 50 environmental samples by thin-layer chromatography,high efficiency liquid chromatography and spectrophotometry.It was found that the optimum temperature and pH is 28 ℃ and 6.5 for this strain,respectively.One loopful of the plate culture was inoculated into 100 mL medium containing 0.5% anethole as carbon source incubated at 30 ℃ for 60 h with reciprocal shaking(200 strocks/min),the ratio conversion of anisaldehyde is up to 5.08%.According to the morphological features,the results of physiological and biochemical experiments and 16S rDNA sequence analysis,this strain was identified as Burkholderia sp.

Abstract:The objectiveof this study is to establish direct and indirect competitive enzyme-linked immunoassay for detection of melamine.For this,BALB/c mice were immunized with MEL-BSA,after a fusion of mouse spleen cells with SP2/0 cells,the hybridoma cells secreting monoclonal antibody against MEL were generated.MEL-mAb was produced by ascites in mice.Melamine was conjugated with HRP,and the conjugates activity was identified.MEL-OVA and MEL mAb were coated in wells respectively,standard melamine were used as inhibitors,direct and indirect competitive ELISA were compared in sensitivity,work range and testing time.Four hybridism cell strains were obtained,which could stably secrete mAbs against melamine.One of them,C4 strain,had a titers of 1∶104 at least in ascites by indirect ELISA and a high affinity constant(Ka) with 2.92×108L/mol.IC50 of direct and indirect competitive ELISA methods were 3.12 μg/L and 56.88 μg/L respectively,and their work ranges were 0.1~1000 μg/L and 0.05~10 μg/L,respectively.Both direct and indirect competitive ELISA methods can be used for the detection of melamine,while the latter is more sensitive and suitable for further research.

Abstract:In this study,A strain,named Lactobacillus plant JD.L which could tolerate low pH and high shearing was selected.Then the nutrient and environmental conditions were optimized and listed as follows: hydrolysate of cottonseed-meal as fermentation medium,temperature 51 ℃,pH 6.2,ORP was-100mv,fed-batch rate 0.05/h Giving the characteristics of the liquid which was produced by continuous fermentation of cell recycling sodium salt method,microfiltration membrane whose diameter is 1μm was choosed to do protecting filtration.Then,the basic parameter of embrane filtration was determined by ultrafiltration whose diameter is 100nm and nano-filtration equipments whose molecular weight is 300.