Abstract:Escherichia coli has been widely used as a host system to express recombinant proteins. The expression of heterogeneous protein in E.coli tends to form insoluble inclusion bodies,whereas the export of recombinant protein to periplasmic or extracellular of cells has a great facility for folding correctly and simplifying downstream purification.Signal peptides play important roles in extracellular proteins secretion across the membranes.This review summarizes the current knowledge of the mechanism of translocation pathways and several general secretion systems.The effects of signal peptide sequence and structure character on protein secretion efficiency and available strategies developed to enhance secretion of recombinant proteins ]were also illustrated.Moreover,we discussed the recent advances in successful secretory expression of recombinant proteins in E.coli.The future prospects and the guidance for expression technology development of industrial enzyme preparation and protein pharmaceutic are addressed.

Abstract:The review firstly introduce the fundamental principles and experimental date handling methods of NIR spectroscopy.Then the progress of the nondestructive testing application on apples in the aspects of internal attributes such as sugar degree and acidity and of internal defect such as browning and diseases were summarized Furthermore,the perspctives of research and application of of near-infrared nondestructive testing technology on apples were provided.

Abstract:In this study,with the leaves of Perilla frutescens were used as explant,effect of different concentrations of the hormone combination on inducing callus in B5 medium were studied by orthogonal test.It was found that the optimum medium for callus induction is B5 + 2,4- D1.0 mg/L+KT0.4 mg/L+6-BA1.0 mg/L+NAA1.5 mg/L,under the optimum conditions, the highest induction rate was achieved.Furthermore,the content of rosmarinic acid in calli after 40 days culture was achieved at 3.85%,however,the value in the leaves of Perilla frutescens was only 0.25%.The results here provided a theoretical basis for the establishment of high-yielding cell lines.

Abstract:The effects of L-Phenylalanine(L-Phe) on crystallization and nucleation of L-Glutamic acid(L-Glu) were investigated in this study by = simulating L-glutamic acid precipitation process through changing pH of monosodium glutamate solution with diluted sulphuric acid.The results indicated that the amount of L-Phe did not affect the L-Glu solubility,but the addition of L-Phe could be absorbed and imbedded on the surface/inside of the crystals of LGlu, thus repressing the crystals production withβform and changing the size distribution of the crystals with a form(crystals sizes decreases with the increased L-Phe addition amount). The mathematical analysis/model revealed that the nucleation kinetics parameters,solid/liquid surface tension(σ),free energy(△G),critical nucleation radius(rc) and maximum nucleation rate(A) in L-Glu crystallization were reduced,leading a lower nucleation rate(J) of L-Glu when increasing the L-Phe addition amount.

Abstract:The aim of this study is to elucidate the effect of A.flavus on protease and amylase production by A.oryzae and the influence of A.oryzae on the biosynthesis of AFB1 by A. flavus.In addition,the ability of A.oryzae to degrade AFB1 was evaluated.Results reveal that after 10 days,the enzyme activity of acid protease,neural protease,alkali protease andαamylase produced by A.oryzae were reduced 3.1,3.2,9.1 and 6.95 time by A.flavus,respectively. It was found that the production of AFB1 was efficient restrained by A.oryzae with the inhibition percentage from 75%to 90.91%during the incubation time.However,A. oryzae can not degrade AFB,.

Abstract:For the IL-2-HSA expression with Pichia pastoris,methanol concentration and pH during induction phase are two important parameters affecting heterologous protein production and should be strictly controlled at adequate levels.In this study,based on the effective recognition of physiological status and characteristics of parameters,an auto-associative neural network (AANN) model was used for two-stage fault diagnosis in Pichia pastoris fermentation processes.The optimized AANN could provide on-line and accurate fault alarm for Pichia pastoris induction stage.It was potentially helpful in supplying useful information for removing fault and recovering abnormal fermentation.When detecting methanol over-feeding,glycerol limited feeding could improve the cell activity and release the toxicity of methanol.

Abstract:In this study,affinity protocols were developed for the preparation of cholesterol oxidase (COD) from recombinant bacteria,a COD gene from Brevibacterium sp.(DQ345780) was expressed in Escherichia coli BL21(DE3),Riboflavin 5’-phosphate and 7-chroroalloxazine were chosen as the affinity ligands,and they were coupled with Sepharose CL 4B through spacers. After one step of affinity binding with the two mediums,the enzyme could be extracted with high purity.The yields of the enzyme purified with the two mediums were 9.4%and 9.9%,respectively,and the recoveries of typical cholesterol oxidase activity were 85.2%and 93.4%.The purified cholesterol oxidases were 98.0%and 97.5%pure with SDS-PAGE analysis. On SDS-PAGE gel,the enzyme was a single polypeptide with the mass of～50 kDa.The theoretical maximum absorption Qmax were 71.0 and 78.5 mg/g medium;the desorption constant K_d of the two mediums on the mediums were 12.8 and 7.3 g/g medium.

Abstract:The extraction conditions for SDF from soybean were optimized with single factor experiment and orthogonal design in this study and listed as follows:the time of enzymic hydrolysation 1.5h,enzymic amount 0.3%,the temperature of enzymic hydrolysation 45℃,pH4.5. with the enzyme from soubean,the effect of SDF on bayberry juice was carefully investigated. Based on the results of single factor experiments,the amount of CMC—Na,xanthan,pectin and SDF were selected as independent variables,deposition ratio and△OD as responses variables. Furthermore,the optimum conditions were achieved by using central composite design and response surface analysis and listed as follows;CMC -Na 0.0562%,xanthan 0.034%,pectin 0. 06%,SDF 4.82%。

Abstract:In this study,transglutaminase was adopted to catalyze wool keratin cross-linked and the effect of reaction conditions such as enzyme dosage,pH value of film-forming solution, temperature,treatment time on the mechanical properties of the film were determined.In addition, the effect of enzymatic cross-linking reaction on the stability of the wool keratin film in hot water was investigated.The keratin protein molecular change induced by TGase-mediated cross-linking was analyzed by SDS-PAGE.The results showed that,TGase-catalyzed preparation of keratin film could increase tensile strength and stability of water,but decrease the elongation. The optimum conditions were as follows:30 U/g wool keratin of TGase,40℃,pH 7.5 of film-forming solutions,18 h of treatment time.SDS-PAGE result demonstrated that new biopolymers with higher molecular weight from wool keratin were formed by using TGase.

Abstract:The target of this study is to compare the sober-up effect of Radix Puerariae and Flos Pueraria and the relationship of puerarin content and sober-up effect.For this,the sleeping time and the blood alcohol concentration of mice,that feed with the extract of Radix Puerariae or Flos Pueraria and feed and 5.75g/kg·bw alcohol after 30 min,were determined..It was found that t the sleeping time was decreaed by 43.3%(2.5 g/kg·bw) and 48.7%(7.5g/kg·bw) by PRW,and 51.1%(2.5 g/kg·bw).53.6%(7.5g/kg·bw) by PREThe mendium and high dose of PRW or PRE could inhibit absorption of alcohol and reduce the concentration of alcohol,and the high dose of PFWand PFE had a slightly effect on the alcohol concentration, only appearing Significant difference at 240 min.From the above results,it was concluded that the sober-up effect of Radix Puerariae is better than that of Flos Puerariaands a good positive correlation between the dose of puerarin in the PR and sober-up effect.

Abstract:In this study,the effect of ozone on postharvest physiology and storage diseases of ’ Dangshansu’ pear during cold storageC slowly cooled to 0±0.5℃) was investigated.During cold storageC slowly cooled to 0±0.5℃),the fruits were treated with 4 mg/m3 ozone for three hours every day in entire storage,the physiological indicators and decay incidence were measured regularly,In addition,its inhibitory effect on Penicillium expansum,Physalospora piricola and Monilinia fructigena(causes of Penicillium,Ring spot and Brown rot,respectively) was studied both in vitro and in vivo.It was found that ozone remarkablyinhibited respiration rate,delayed the decrease of total soluble solids(TSS),titratable acidity CTA) and inhibited the increase of malondiadehyde(MDA) content,reduced the rate of fruit decay effectively,but a little effect on fruit firmness.Furthermore,ozone-enrichment resulted in a substantial decline in spore production as well as visible lesion development in all treated.Taken as a whole, the results imply that the technology that ozone gas was used in treatmeting ’Dangshansu’ pear in the cold storage not only significantly maintained higher storage quality,but also reduced the incidence of decay.

Abstract:In order to study the properties of biomagnetism,a kind of magnetotactic bacteria TH-1 which is able to respond and orient along the lines of terrestrial or artificial magnmetic fields was isolated from Taihu lake.TH-1 is the first reported magnetotactic bacterium isolated from Taihu lake.Morphological observation was carried out using the transmission electron microscope and the results showed that magnetic cells each possess several magnetosomes that is circular-shaped and 10 nm-100 nm in diameter,which distributed in cytoplasm and the front cell wall.The Energy dispersive X-ray spectrum of magnetosome indicates that stain TH-1 consists of three mineral elements Fe,S and O.The magnetic properties both of the bacteria and magnetosomes were studied and a preliminary biochemical identification of the bacteria was carried out.All the above results demonstrated that strain TH-1 is magnetotactic bacteria.

Abstract:In this study,the optimum formula of the processed vegetable for the best sensory evaluation was investigated,and listed as follows:carrot 10%,garlic sprout 17%,lettuce 23%,bean curd 5%,pickled cucumbers 10%,soybean oil 1.5%,salt 0.7%.Furthermore, the antibiosis effect of Nisin and potassium sorbate on the precessed vegetable was studied, which can extend the field of controlling the bacteria,reduce sterilization intensity and the loss of flavor substance.The result shows that;the bacteria can be controlled effectively when the concentration of Nisin and potassium sorbate were 0.08 g/kg and 0.30 g/kg,sterilization conditions reduced to 85℃for 10 min.

Abstract:The low-cost laver was hydrolyzed with neutral protease and aminopeptidase in this study.The antioxidative peptides were purified initially by adding 60%ethanol to remove polysaccharides in the hydrolysate.The supernatant was further purified through Sephadex G-10 gel,DEAE-52 anion-exchange and SOURCE 3RPC to get more purer enzymatic laver antioxidative peptides(ELAP).The scavenging activities of Superoxide-radical,DPPH radical and Hydroxyl -radical were 23.25%,47.12%and 47.12%respectively when the content of the ELAP was at 100μg/mL.Compared to vitamin C at the same content(100μg/mL),the scavenging activities in the ELAP were 0.79,0.87 and 0.91 times of the activities in vitamin C,Furthermore, the reducing ability of the low-cost laver peptides was 1.23 times than that of vitamin C. According to the chromatographic of analytical reverse-phase high performance liquid chromatography (RP-HPLC).the purity of ELAP was up to 87.44%.The ELAP was identified as a hexapeptide AGVGTG(Asp-Gly-Val-Gly-Tyr-Gly) with analysis of the ultra-performance liq- uid chromatography-quadrupole time-of-flight mass spectrometry(Q-TOF-MS).The composition of the hexapeptideC AGVGTG) in the ELAP which contained Tyr and Gly has the typical function of antioxidation.

Abstract:Effects of thermal treatment and fermentation on gel properties of 7kinds of conventional freshwater fish surimi gel were investigated.The gel properties,whiteness,folding strength and water holding capacity of surimi gel were investigated for the comparison of 7 kinds of conventional freshwater fish surimi gel which were processed by thermal treatment and fermentation,including black carp,grass carp,silver carp,bighead carp,common carp,crucian and gurnard.The breaking strength and gel strength of common carp surimi gel by thermal treatment were highest,respectively was 771.83 g、7 733.86 gmm.The breaking strength,deformation and gel strength of crucian surimi gel were lowest,484.77 g、7.56 mm、3 667.38 gmm.Among fermented surimi gel,the breaking strength,deformation and gel strength of sliver carp surimi gel were highest,up to 908.22 g、13.20 mm、11 995.08 gmm. The deformation and gel strength of sliver black carp surimi gel were lowest,9.87 mm、6 690.96 gmm respectively.The differences of water holding capacity and whiteness among different species were significant.Compared with the traditional thermal treated surimi gel,the gel properties of fermented surimi gel were higher,and its breaking strength,deformation and gel strength were enhanced to a certain extent.The increase of silver carp surimi gel was highest, 64.88%,11.86%,83.37%respectively.

Abstract:Crisp tilapia bone chips is high nutritional value and good flavour,made from the tilapia bone.The protocol for producing Crisp Tilapia Bone Chips was include shattered,add ed ingredients.dried and fried.In this study,the optimum process conditions of the fishbone leisure food was determined by the a single factor experiment and orthogonal test and listed as follows: the ratio of Glutinous rice starch and corn starch 6:4,the feasible pre-drying time 50 min,cooked under 180℃ for 50s.followed by the above conditons,an optimal crispness and color of Crisp Tilapia Bone Chips was achieved.

Abstract:The objective of this manuscript is to measure and analysis the antioxidant and antibacterial activity of the pigment which is extracted from the flower of Cercis chinensis.A sequence of experiments was conducted to measure the above parameters,such as spectrophotometry and inhibiting bacteria circle diameter measure.The results demonstrate that the pigment has strong reduction and is able to effectively scavenge hydroxyl radical and superanion radical in vitro.Moreover,its scavenging effect has positive correlation with its concentration. When the pigment concentration is 0.48 mg/mL,the reducing power is identical to that of 0.1 mg/mL VC,and the hydroxyl radical and superanion radical eradication rates are 59.3%and 96.1%,respectively.At the same concentration,the pigment has significant concentrationdependent inhibitory effect against E.coli and Staphyloccus aureus and Bacillus subtilis.Diameters of inhibiting bacteria circle of the above three kinds of bacteria are 9.46 mm,9.36 mm, 8.14 mm,respectively.From the aboved results,it can concluded that the pigment has strong antioxidant and antibacterial activity.