Abstract:Freshness is an important quality indicator of aquatic products and a main factor to determine its price.As an emerging food preservation technology,radiation preservation technology is the use of ionizing radiation to irradiate various aquatic products for controlling insects,bacteria and physiological activities to extend the storage and shelf life of aquatic products.The characteristics of,the dose effect on the aquatic product quality of,and the security problems of radiation preservation technology have been summarized and its developmental prospect been forecasted to provide references for research directions on preservation of aquatic products.

Abstract:The effect of biotin,VB 1 ,VB 3 ,VB 5 ,VB 6 ,inositol,para aminobenzoic acid(PABA) and VC on the growth of shiraia sp.SUPER-H168 and perylenequinones production were studied with single factor experiment. The results showed that biotin and PABA strongly improved the biomass of cell, but low concentration of them could inhibit the pigment production. VB 5 and VB 1 slightly increased the production of pigment,and their optimum concentration were 0.5,0.05,0.05 mg/L. Although VB 6 could improve the growth of fungi,the synthesis of the pigments was inhibited. The mixed vitamins containing VB 1 ,VB 3 ,inositol,VB 5 and VC was added into 5L -fermentation medium with the optimum concentration because of their improvement of pigment yield,and their effect on the growth of shiraia sp.SUPER -H168 and pigment yield was studied. The final biomass and pigment yield were increased by 33.7% and 75% respectively compared to the experiment without vitamin.

Abstract:A codon-optimized gene encoding a hyperthermostable xylanase belongs to the glycoside hydrolase family 11 (abbreviated as Syxyn11) has been cloned into the expression plasmid pPIC9K (named pPIC9K-Syxyn11). The pPIC9K-Syxyn11 was linearized with SalⅠ and integrated into the genome of Pichia pastoris GS115 by electroporation. The recombinant P. pastoris GS115/Syxyn11 was screened by G418 and then was induced with methanol to express SyXyn11. The SyXyn11 activity expressed by P. pastoris transformant reached 17.74 U/mL. The molecular weight of SyXyn11 was estimated to be 31 000 by SDS-PAGE. The SyXyn11 displayed the highest activity at 85 ℃and pH 6.5. It was highly stable at a temperature of 80 ℃ or below,and at a pH range of 5.0~ 7.5. Its activity was not significantly affected by most of metal ions tested and EDTA. This revealed that Syxyn11 was successfully expressed in P. pastoris and remained the high thermostability.

Abstract:The collagen peptides from chicken skin has been extracted by using enzyme method. In addition,the effects of enzyme types,enzyme concentration,hydrolysis time,hydrolysis temperature and pH on peptide hydrolysis were studied,and the extraction conditions were optimized by orthogonal experiment. The results shows that the optimum enzyme was papain add trypsin add flavorzyme and the optimum concentration of enzyme was 0.9%,the time of enzyme hydrolysis was 3 hours,the temperature of enzyme hydrolysis was 45 ℃ and pH was 7.

Abstract:The components for cordycepin production by Cordyceps militaris JN168 were optimized with single factor experiment and response surface methodology. The purpose of this study is to determine the best fermentation medium for cordycepin production by Cordyceps militaris JN168. Results showed that glucose and beef extract are the appropriate carbon and nitrogen sources with an optimal concentration of 40 g/L and 15 g/L,respectively. And adding inorganic salt is MgSO 4 , K 2 HPO 4 ,CaCl 2 and Na 2 HPO 4 with an optimal concentration of 0.76 g/L,0.63 g/L,0.66 g/L and 0.67 g/L respectively. The cordycepin concentration in the fermentation broth after optimization is 633.47 mg/L,which is 6 times before the optimization.

Abstract:It is to establish HEK293 cell line which could stably express sweet taste receptor protein T1R2/T1R3.Firstly,extract total mRNA from mouse tongue tissue,then amplify Gα15,T1R2 and T1R3 target gene fragment by RT-PCR with self-designed primers and above total mRNA template.Then,establish the recombinant plasmid pEGFP-C1-Gα15,pDsRed1-N1-T1R2,pcDNATM6.2/N-YFP-DEST-T1R3 and introduce them into the HEK293 cells by liposome.After resistance screening,the HEK293 cell line with the ability of stable expressing T1R2/T1R3 was obtained in a limit dilution method.Finally,the stable cell line with sweet receptor protein T1R2/ T1R3 was identified by RT-PCR,fluorescence microscopy and Western blot.The results in gene and protein level show that Gα15、T1R2/T1R3 are successfully introduced into HEK293 cell line and are stably expressed.The establishment of HEK293 cell line provides a stable cell source for the study of sweetness mechanism in vitro(such as sweet recognition thermodynamics,etc.) at cell

Abstract:Eight Bacillus strains were screened out successfully from four honey samples.Theses strains were identified by colony morphology,physiological and biochemical characteristics,and 16S rRNA gene sequence analisis.Eight isolates exhibited antimicrobial activity against Escherichia coli,Shigella dysenteriae S7NaCl and Serratia marcescens SYBCT02.Based on the study of antimicrobial activity by the isolates of bacteria,it was found that some strains might inhibit other colonies growth through competitive,and some strains might inhibit other colonies growth by its metabolism produced inhibitory substances.

Abstract:To obtain the optimal conditions of ever-fresh lactone tofu and simplify the evaluation and prediction of fresh preservation effect,single-factor experiments and orthogonal design L9(34) were conducted involving sterilization temperature,sterilization time,consumption of coagulation.The results showed that:the preservation period could be improved significantly at the sterilization temperature of 87 ℃ with sterilization time of 30 min,with coagulant(GDL) concentration at 0.4% and preservative addition at 0.45 g/kg,natural pH and refrigerator temperature at 4 ℃.Preservation index was determined by the two main indicators through factor analyses followed by reducing dimensionality of original amount.The equations we found in the process are Z1=-0.962X1+ 0.883X2+0.785X3-0.302X4+4.594E-02X5,and Z2=0.246X1-0.395X2+0.545X3+0.934X4-0.932X5.It is not only just providing a feasible technical way to keep lactone tofu fresh,but also convenient for quality evaluation and prediction.

Abstract:The aim of this study is to find a way to reuse Schisandra chinensis fruits wastes after lignans extration.Polysaccharide tabled as SCP-0 was separated by hot-water extraction and ethanol precipitation,and then purified by polyamide column chromatography and Sephacryl S-300 HR column chromatography.After purity identification,the antioxidant activities of SCP-0 were investigated and the results showed a noticeable scavenging activity against hydroxyl radical and DPPH with IC50 of 14.5 mg/mL and 2.1 mg/mL respectively.However,superoxide anion scavenging activity of SCP-0 was hardly observed and certain ability of restraint on lard oxidation was observed.

Abstract:To establish a standard fourier transform infrared(FT-IR) spectral library and a FT-IR method of differentiation and identification of three species of Listeria,viz Listeria monocytogenes,Listeria iuanuii and Listeria innocua,FT-IR fingerprint absorption spectra of three species of Listeria were collected,and a standard spectral derivatives library was created.Combined with chemometrics methods,two cluster models of principal component analysis(PCA) and hierarchical cluster analysis(HCA) were established.It was found that three species of Listeria could be well differentiated and identified,and the standard spectral derivatives library created could be used to compare with those of target Listeria and identify them.As a rapid,easy-to-use and accurate technique,FT-IR spectroscopy is an effective tool to differentiate and identify three species of Listeria studied here.

Abstract:The vacuum microwave puffing technology was used to manufacture fish taste crisp,taking the low-value marine fish as main raw material.The best formulation is determined by several single factor experiments with different proportion of fish,starch,salt,sugar,and other flavorings,and the orthogonal experiment which shows the best volume of salt,sugar and starch.The indicators include color,puffed rate and sensory index.Products were packaged with thick aluminum bag and thin PE bag,by vacuum processing and not respectively and then placed in 37 ℃ for quality testing.According to the color,water activity,moisture content and fat oxidation value determines the best preservation method.The best formula of fish taste crisp is 100 g sea fish,14g potato starch,1.75 g salt,2 g sugar and 0.8 g chives,ginger and garlic seasoning.The best preservation method is using thick aluminum bag and taking vaccum processing.The products obtained can show a smooth surface,crunch taste,uniform expansion rate and excellent long-term preservation.

Abstract:The aim of this study was to establish a detection method for identification of food borne pathogenic bacteria by using pyrosequencing technology.For this,one pair of polymerase chain reaction(PCR) primers and one pyrosequencing sequencing primer of Salmonellla spp,Listeria monocytogenes,Staphylococcus aureus and Shigella cereus was designed,then the pyrosequencing reaction system and conditions was optimized.the sensitivity of this method was arrived at 10 CFU/mL and has been proven to be highly efficiency,rapid,exact and easy handling.The results provide an informative supplement to fast identified food-borne pathogenic bacteria.

Abstract:This paper is designed to extract gelatin from tilapia bone with the method of Enzymatic Hydrolysis.The effect of demineralizing and hydrolyzing conditions on extraction were analysed.In this research we can show the demineralizing condition is tilapia bone added to 0.6mol/L HCl with solution-to-bone ratio 5 mL/g for 6 h and change the acid solution every 1.5 h.the optimal conditions of enzymolysis is the temperature 46.5 ℃,pH 5.3,time72 min,the protease solution-tobone ratio was 3 mL/g,amount of enzyme 2480 U/g(bones).

Abstract:The stability of interleukin2-HSA fusion protein was examined in different pH and buffer solution environments using SDS-PAGE and SE-HPLC.A pH-5 solution of Acetic acid Sodium acetate buffer is found to be more suitable for IL2-HSA to preserve stability.Several excipients was tested for the effect to protein stability under elevated storage temperature and photostability test was taken,the protein was proven to be stable throughout photo-stability test,after a 6month-long storage NaCl is considered to be a better excipient for IL2-HSA than its rivals.

Abstract:In this article,the optimal parameters for extracting Aureofuscin were investigated by studying the adsorption and desorption rate of Aureofuscin among eight macroporous resins. The determination of the physical and chemical properties of Aureofuscin was carried by IR,NMR spectrum method. The results showed that X -5 resin possessed higher absorption and desorption rate,the finished Aureofuscin product was detected by IR and NMR spectrum,proved that the isolation and purification technology achieved general ideal effect.

Abstract:This work describes the development of a PCR system for the authentication of turkey derived material in food and feed.A real-time PCR method was established for detection of turkey derived material. The method was specific for turkey derived material,and the limit of detection was determined as 0.001%. The PCR procedure is suitable for the detection of turkey derived material in food and feed.

Abstract:This study dynamically analyzed physical and chemical character,cellulose activity and protease activity,volatile components in the process of fermentation.It showed that the amino acid nitrogen,acid was higher than before.The number of microbe cell,the activity of cellulases and protease,the concentration of deoxidize sugar,lipid,total acid decreased during later fermentation.Acid,lipid and pyrazine were increased significantly during the former and the later fermentation while macromolecular hydrocarbon and macromolecular ketone were decreased obviously.We could know that the influence of microbe affects the progress of the fermentation,and it changes the internal composition,the quality and the flavor.

Abstract:We collected many samples from different locations,then isolated and purified single colony. By fermentation,the products whether have lipase inhibition activity as a screening indicator. We find a good strain Sf16 after we cultured 2013 wild strains. The morphological characteristics of colony,aerial hyphae,sporothrix and spores and the growth performance characteristics in different carbon sources medium of strain Sf16,as well as some physiological and biochemical characteristics were observed. Extract the DNA,amplified and determined the 16SrDNA.Then homology search in database,compared and constructed the phylogenetic tree. Inhibitor-producing strain Sf16 preliminary identification by means of morphological and molecular biology techniques,the result is Streptomyces sp.