Abstract:α-keto acids,a kind of bifunctional substances combined with biological activities,are widely used in feed,food additives,chemical synthesis,etc. Currently α-keto acids are produced by chemical synthesis,with the disadvantages of mutiple reaction steps,serious environmental pollution,and low product yield. Compared with the chemical synthesis,biotechnological production of α-keto acids is an abstractive approach due to the low cost,mild conversion conditions as well as environment-friendly mode of production,which have attracted increasingly attention of researchers.In this work,we reviewed the progress of chemical synthesis method,fermentation method,and biotransformation to produce α-keto acids. Finally,the development prospects in this field were outlined.

Abstract:The article reviews the recent research developments in gelation mechanism,influencing factors and research methods. On this basis,the application of vegetables protein gelation is stated in the field of food and others. Then the main problems in this research field have been presented,which were for the purpose of providing reference for further studying the degradation mechanism and the functional properties,extended the application of vegetables protein gelation.

Abstract:In order to prepare complete antigen against 3-amino-2-oxazolidinone(AOZ),which is one of main metabolites of furazolidone in animal,AOZ was synthesized using hydrazine and dimethyl carbonate. Then,3-(4-carboxy benzyl methylene)-amino-2-oxazolidinone(CPAOZ) was prepared as hapten based on AOZ. Three different methods including water-soluble carbodiimide method(EDC),condensation esterification(DCC) and mixed anhydride method(MA) method were used to prepare complete antigens by coupling CPAOZ to ovalbumin(OVA). All the products were characterized with UV spectrum. The coupling ratios of three artificial antigens were respectively 8、12、17. Under the optimized conditions,the prepared antigens were used to establish inhibition curves of AOZ and CPAOZ by enzyme-linked immunoassay(ELISA). Results showed that the lowest half inhibition concentration(IC50) of AOZ was 1.1 ng/mL sourced from coating antigen prepared using mixed anhydride method(MA) method.

Abstract:In this paper,quality changes in Pampus argenteus during chilled storage(4+1) ℃ were investigated in the aspects of sensory,pH value and aerobic plate count(APC),and its bacterial flora changes were also qualitatively and quantitatively studied. The results showed that TPC and the mean values of pH of sample at the initial storage were(3.967 ±0.012)lg(CFU/g),(7.217 ±0.015) respectively. 45.92% gram negative bacteria and 54.08% gram positive bacteria were found in it,the dominant bacterial flora were composed of Staphylococcus saprophyticus(28.81%),Staphylococcus sciuri(15.38%),Psychrobacter spp.(12.09%),Pseudomonas fragi(9.02%),Pseudomonas fluorescens(8.53%) and Shewanella putrefaciens(6.39%). A few percent of Enterobacter agglomerans,Microbacterium esteraromaticum and Kocuria rhizophila were also found.The growth of Staphylococcus saprophyticus and Staphylococcus sciuri were inhibited during storage at low temperature,then the composition of bacteria flora gradually became simple,and the percent of gram negative bacteria which were suitable for low temperature increased significantly. The gram negative bacteria were 83.82%,95.86%,96.88% and 93.57% in the period of 3rd,5th,7th,9th day respectively,indicating Pseudomonas spp.(45.71%) and Shewanella putrefaciens(33.57%) were the most predominated spoilage bacteria of Pampus argenteus stored at(4+1) ℃. The species changes of Pseudomonas spp. indicated that the major species were Pseudomonas fluorescens(35.00%) and Pseudomonas fragi(10.71%).

Abstract:By ascorbic acid,citric acid,blanching three ways for fresh pear slices care independent and composite color processing,single factor test and orthogonal to optimize optimum color protection program;by adding xanthan gum,pectin,chlorinecalcium,white sugar vacuum infiltration processing of fresh pear slices,the optimum Paul brittle program;contrast maltodextrin,lactose,glucose,the pear crisps anti-adhesion effect obtained the best anti-blocking scheme. The results show that the level of ascorbic acid on the color difference is greater than the citric acid than blanching. Orthogonal test the results of an alternative sulfur color fixative new the color protection program:0.25 g/dL ascorbic acid and 0.10 g/dL citric acid soak for 10 minutes,55 ℃ blanching minutes;crispness-programs best ratio of 0.10 g/dL xanthan gum,0.04 g/dL pectin and 0.04 g/dL calcium chloride,and 0.12 g/dL white sugar compound;Anti-blocking scheme:the mass fraction of5 g/dL maltodextrin soak for 5 min.

Abstract:The effect of different key factors on production of catalase(CAT) in recombinant Escherichia coli was analyzed by orthogonal experiment. The optimum fermentation condition in shake flask was determined:glycerol 5 g/L,yeast extract 35 g/L,initial pH 7.5,and induction temperature 30 ℃. During production of CAT in 3 L fermentor, the highest activity reached20 117.2 U/mL at the optimum stirring speed(300 r/min). The optimum initial glycerol concentration was 10 g/L. The highest activity reached 28 243.0 U/mL when the speed of glycerol supplement was0.67 g/(L·h). When 16.7 g/L glycerol was supplemented at start induction,the CAT activity could reach 50 369.5 U/mL after incubation for 47 h,which was 2.5 fold of that before optimization.

Abstract:The optimum conditions of extracting pigment from the solid state fermentation culture of Pycnoporus sanguineus SYBC-L7 were studied,and the physicochemical properties of this pigment were also analyzed. The results showed that the pigment could be optimum produced by solid-state fermentation with wood chips. Using methanol as the extraction solvent,the pigment could be maximally extracted from the solid culture at 35 ℃ after 40 min with water bath. The extraction solvent was yellow with a maximum absorption wavelength of 430 nm. The pigment has a good thermal resistance as well as acid resistance,and it cannot be affected by common oxidizing and reducing agents.

Abstract:Electrolyzed water ice is a relatively new preservation and cold sterilization technology developed in recent years. To study the changes in physicochemical properties of electrolyzed water ice during storage and their effect on inactivation of Vibrio parahaemolyticus,five types of electrolyzed water ice prepared from different concentration of sodium chloride solution(0.75,1,1.25,1.5,1.75 g/L) and were frozen at-36 ℃.And a set of physicochemical properties, including pH values,oxidation reduction potential(ORP) and available chlorine concentration(ACC),were measured on storage hours(0-10 h),and the bactericidal efficiency on Vibrio parahaemolyticus by electrolyzed water ice was studied during storage. The results showed that pH value did not have significant difference(p >0.05) from 0 to 6h,while after 6 h the rate of pH change of electrolyzed water ice prepared from NaCl ≤1 g/L was less than that of NaCl concentration >1 g/L. ORP and ACC decreased gradually,and the ORP changes almost follow the same trend. However,the ACC loss rate of NaCl >1.5 g/L was higher than that of NaCl ≤1.5 g/L. Compared sterilization with all other adjacent concentration difference,the difference of the bactericidal efficiency on Vibrio parahaemolyticus by the electrolyzed water ice of NaCl concentration 1.5 g/L and 1.25 g/L,the highest ratio was to 117.6 times. According to the correlation analysis,the respective correlation coefficients of pH,ORP,ACC on the bactericidal capacity were 0.831,0.787 and 0.944.

Abstract:This paper investigated the model,color and texture of potato slices dried by pulse-spouted microwave vacuum drying(PSMVD) at the pressure range of 11.8~15.0 kPa using different microwave power,pulse frequency and pretreated methods. The results showed that the Midilli’s model is superior to other models. The diffusion coefficient of potato slices increased when the microwave power increased,but the drying time for blanched potatoes was much longer. Compared with conventional microwave vacuum drying,PSMVD exhibited a shorter drying time,more uniformity,better color and higher quality.

Abstract:For obtaining new antibiotics and applying it to food preservation,A Streptomyce producing high antibacterial substance was screened from a sample obtained from Xuzhou kui river of Jiangsu. This strain was identified through it’s morphological,physiological and biochemical properties. 16S rDNA sequence analysis of HMJ-7 showed this strain was closely to Streptomyces griseoruber to 99%,So,it was identified as Griseorubro violaceus. The antibacterial experiment result showed that the antibacterial substance can obviously inhibit the growth of E. coli,Staphyloccocus aureus Rosenbach,Micrococcus luteus,Bacillus cereus and yeast. But can’t inhibit the growth of Aspergillus niger,Aspergillus flavus,Aspergillus oryzae and other fungi. The following experiment result indicated that the antibacterial substance produced by this strain was stable at differen temperature,pH,ultraviolet light and organic solvent condition.

Abstract:The course of solid state fermentation for protein feed production from notoginseng residues by Phanerochaete Chrysosporium 5.776. and Candida utilis 2.281 was carried out,and microbial growth and starch degradation kinetic models were established. The result shows that with the dry weight reduction ratio of fermenting medium as the indirect parameter for expressing the microbial concentration,Logistic model is suitable for the microbial growth kinetics,and the maximum dry weight reduction ratio Xm=49.68%,specific growth rate constant μ=0.042 90 h-1. The microbial growth rate arrives at the peak point after the fermentation of 84.8 hours. Exponential model is suitable for the starch degradation kinetics,and the content of starch decreases with 26percentages,and the degradation rate constant is 0.015 9 h-1. The degradation rate of starch decreases gradually with the time extension.

Abstract:Plasmid extraction is an important but difficult step of the genetic engineering operations,because of the yeasts cells with tough and unbreakable cell wall. For getting one fast,simple,efficient and stable method of plasmid extraction from yeasts,we employed the techniques of agarose gel electrophoresis,spectrophotometer and PCR amplification,and compared the yield,purity of plasmids which were isolated from yeasts with the methods of glass beads-liquid nitrogen,snailase and kit. The results showed that the method of glass beads-liquid nitrogen had the advantages of high efficiency,good quality,low cost,simple operation in contrast to the other two methods,and it can be used as a laboratory scale commonly method for extraction of yeast plasmid.

Abstract:Study on eggs storage effects of compound coating antistaling agent of polysaccharide. at room temperature(25~28 ℃) and relative humidity(60%~75%) were investigated. The antistaling agent was composed of Sophoraalopecuroides bean polysaccharide for the coating matrix,glycerin and Chinese herbal medicine Coptis chinensis Franch and Rheum palmatum extract was added to improve the film flexibility CaCl2and citric acid as film-forming additives. The results showed that after 30 days’ of storage,compared with the control group at room temperature,By determining such indexes as the rate of weight loss of eggs,the relative density,Hough unit,egg yolk index,pH value of egg and TVB-N value than in the control group,the shelf life was extended. and the best freshkeeping and storage effect comes from the treatment by using the coating Prescription 4.

Abstract:Compare the methods of extracting nucleic acid of Listeria monocytogenes in four food matrices. Taking L.monocytogenes as our research object,we picked and tested four widely applicable nucleic acid extraction methods and evaluated their performance by real-time PCR.Results:Tiangen centrifugal column method was very stable,with minimum variation caused by different food matrices. Promega precipitation and magnetic bead methods were more affected by food matrices than others,with a larger variation in final products;Chelex-100 method was quick and convenient,but was only suitable for pure liquid culture or colonies.

Abstract:In order to provide reference for the production quality and safety control of pickled cucumbers in exported Central Asia and Russia,according to the international advanced system of HACCP quality management each link of major hazards in the Russian pickled cucumbers canned production was analysed. The results showed that the four processes including bottling,juice,capping,sterilizing were determined as critical control points(CCP). Moreover,the corresponding control measures were raised.

Abstract:In order to study the Ultrasound-assisted extraction technology of Sphallerocarpus gracilis stem leaves polyphenol and antioxidant activity. Response surface methodology(RSM) was used to establish the mathematical model of solvent extraction extraction to obtain the optimum conditions. The antioxidant activity of the extraction was evaluated by spectrophotometry on its ability of scavenging hydroxyl radical(·OH),1-diphenyl-2-picrylhydrazy(DPPH·) and total reducing power. Based on Box-Behnken design,the optimal process parameters were obtained as:ethanol concentration 75%,extraction temperature 70 ℃,ratio of solid to liquid(g/mL)35,ultrasonic time 30 min. Under the optimal condition,the average yield of polyphenol was 1.1448%.Results indicated that the scavenging effects of the extract on ·OH,DPPH· were significant,the extraction also had slightly total reducing power. And within 0.1 ~0.6 mg/mL concentration,the scavenging effects of Sphallerocarpus gracilis stem leaves polyphenol on·OH,DPPH· was higher than BHT. The Sphallerocarpus gracilis stem leaves polyphenol with good antioxidant activity has the potential to be further developed and utilized as a natural antioxidant.

Abstract:In this manuscript,the effect of the egg yolk powder hydrolysis(Bonepep) on bone metabolism was investigated at rat and human level. When 10 mg/(kg·d) and 100 mg/(kg·d)Bonepep was fed to SD mice led the mice tibia elongation increased by 4.5% and 10.3%,respectively. And the physiological and biochemical indexes of mice were constant when mice were explored to high doses of Bonepep for long time. It was found that Dpyr level in urine was decreased 84.6%,and the thigh bone was significantly reduced when mice was fed Bonepep. For the female volunteers,the level of DPD and NTx,reflect the characters of bone resorption,were not significantly changed,after 5 weeks continuous taking Bonepep. However,the BALP activity,a index for bone formation,was increased by 14.6%. These results demonstrated that the egg yolk powder hydrolysis Bonepep could effectively inhibit osteoclast differentiation but promote bone growth.