Abstract:The influence of alloxan on the immunologic function in mice was studied and the regulation of mice immunity by collagen peptide-Chromium(Ⅲ) complex was also investigated by measuring the cytophagocytosis of macrophage in abdominal cavity, antibody formation cell and T-lymphocyte. It was found that collagen peptide-Chromium(Ⅲ) complex could enhance the cytophagocytosis of macrophage, antibody producing cell count and E-rosette concentration, showing regulation effect on the immunologic damage induced by alloxan.

Abstract:To synthesize the methamphetamine antigen for immunoassay. Functional group was introduced into methamphetamine and then methamphetamine antigen was synthesized by anhydride method using BSA as carrier protein. The reaction was monitored by FTIR, UV scanning, protein electrophoresis and GICA methods. Results: 25 molecules of methamphetamine were conjugated to one molecule of BSA. And the formed conjugate showed confirmed antigenic Activity. Methamphetamine antigen was successfully synthesized and could be used in immunoassay.

Abstract:Transglutaminase from Streptoverticillium SK4.001 was widely used in food industry, but could not directly digest the soybean cake powder, a cheap industrial raw material with high content of proteins. In this paper, hydrolyzed soybean cake powders with different degree of hydrolysis (3%, 5%, 7%, 9% and 12%) were obtained by pH-STAT method and their effects on the transglutaminase production by Streptoverticillium were investigated. The result showed that the yield of transglutaminase was greatly improved by using the hydrolyzate of soybean cake powder as nitrogen source with its content and DH being of 20 g/L and 5%, respectively, and the enzyme activity obviously increased to 4.2 U/mL.

Abstract:Trysin-catalyzed hydrolysis of expressive products of recombinant E.coli BL21 was studied. Results showed that the best reaction temperature, pH, enzyme dosage and reaction time were 37 ℃, 8.0, 90 U/mL, and 4 h, respectively, under which the concentration of VLPVPR was up to 211.1 mg/L.

Abstract:Alginate lyase was successfully purified from fermented broth of V. parahaemolyticus C20 by ultra-filtration, ammonium sulfate precipitation, ion exchange chromatography and size exclusion chromatography. The purified alginate lyase with molecular mass of 40 kD had optimal temperature of 30 ℃ and maintained 90% of its activity after 3.5-hour incubation at 30 ℃. The enzyme with optimal pH of 7.2 was stable within the pH value range of 7.0 to 7.6. Mg2+, Na+, NH4+, Ca2+, methanol and Tween-80 with certain concentration had activation of the enzyme while ethanol, acetone, DTT, urea, SDS, Zn2+, Cu2+, Fe2+ and Al3+ showed inhibition. This enzyme specifically degraded polyguluronate with Km of 1.38 mg/mL and Vmax of 0.052 mg/(ml•min).

Abstract:The effects of different enzymatic treatments on the aromatic components of Puer tea were investigated by the headspace solid-phase micro extraction (HS-SPME) and capillary gas chromatography-mass spectrometry (GC-MS) to determine the volatiles in Puer tea. Results indicated that the kinds of aromatic components of the tea samples treated by enzymes were significantly less than the untreated. 34, 21, 23 and 24 kinds of volatile compounds were identified in the tea samples treated by vacancy, peroxidase, flavourzyme and cellulase, respectively. In addition, the enzymatic treatments greatly improved the contents of methoxy benzene and their derivatives.

Abstract:The variation of bacteria population in sufu fermentation was studied by molecular biology methods. The Genome DNA was extracted from the bacteria in Sufu sample, and its 16S rDNA fragment was amplified by PCR for further cloning and translating. The achieved 40 converters were examined by 16S rDNA PCR, 10 of which were false positive. Then the rest were sequenced bidirectionally for classifying them into different groups according to their homology. Meanwhile, comparison of these sequences with those on GeneBank by using Blast software showed that some genes had significant homology with foregone sequences in the GeneBank. This study enriched the knowledge of bacteria population distribution in sufu fermentation and revealed the relationship between microbe variation and Sufu fermentation.

Abstract:Fully or partially heat-denatured soybean protein isolate (DSPI) had high solubility, which took an important role in the soybean protein industry. Our research showed that the subunits of DSPI were combined with each other via covalent bands and non-covalent bands. The solubility of DSPI were reduced more easily than that of the traditional low denatured SPI by heating at 100% humidity But changes of their solubility were similar when they were heated at 18% or 50% humidity. The salt-solubility of DSPI was lower than that of the traditional low denatured SPI. Besides, aqueous ethanol could not obviously lower the solubility of DSPI. Heating DSPI in 65% ethanol may greatly improve its solubility. The results of this research had significant meaning for further basic researches and industrial application of soybean protein.

Abstract:The influential factors in the plasmid DNA extraction on the quality of the plasmid DNA was investigated, the extraction conditions of plasmid DNA were optimized and the quality-controlling standards were set in order to produce the high-purity plasmid DNA. Effect of temperature inducement on the production of plasmid DNA was studied by increasing the temperature from 37 ℃ to 43 ℃ at intervals of 1 ℃. After 12 hours of cultivation at 42 ℃, the plasmid yield was significantly increased by 66%, which demonstrated that the new method could be used for economically preparation of recombinant plasmids. Moreover, the standard alkaline lysis method for preparation of plasmid DNAs was modified and the optimized procedure was as follows: removing the cell fragments and the epactal proteins by LiCl; precipitating the plasmid DNA by PEG8000 to wipe off the digested RNA; and removing the reliquus protein by Phe-nol-CH3Cl3.In order to obtain the high-purity plasmid DNA, the crude plasmid DNA was further purified by different kinds of chromatography.

Abstract:A functional yogurt was prepared using fresh milk and Nostoc flagelliforme as raw materials. The results showed that the best contents of Nostoc flagelliforme, sucrose, stabilizer and emulisizer were 10%, 10%, 0.2% and 0.15%, respectively. And the best ratio of Lactobacillus bulgaricus to Streptococcus thermophilus, inoculum size and fermentation temperature were1:1, 4% and 44 ℃, respectively. Under those conditions, the yogurt was achieved with high quality.

Abstract:Fish sauce was produced via fermentation of by-products of processed Tilapia with 35% (w/w) of salt for 180 days. Changes of pH, total nitrogen (T-N), amion acid nitrogen (AA-N), total volatile base nitrogen (TVB-N), the non-enzymatic browning index, composition of amion acid were periodically detected. Results showed that the contents of T-N and AA-N were 18.27 mg/mL and 9.05 mg/mL respectively, up to the standard of first grade garos. Prolonging the fermentation time increased the non-enzymatic browning index and TVB-N but decreased the pH values. The product was in rich of Arg, Glu, Ala, Lys and Leu. Besides, the QDA-test showed that the fish sauce was delicious and salty with ammoniacal sapor.

Abstract:The autolysis-enzymolysis method was adopted to prepare yeast extract in order to make full use of the waste beer yeast. The key factors influencing the autolysis of waste beer yeast were optimized, including autolysis promoter, autolysis time and enzymolysis time. Results showed that the autolysis-enzymolysis method was suitable for the yeast extract production. Under the optimized conditions, the yields of amino nitrogen, total nitrogen and solid reached 4.30%, 8.98% and 59.0%, respectively. Furthermore, the physiochemical characteristics of the achieved yeast extract were investigated.

Abstract:Influences of several packing materials on the preservative effect of Biluochun tea are studied. The results show that the packing materials are closely related to the sensory quality and biochemical components of the stored Biluochun tea. Among the examined materials, tinplate pop can shows the best fresh-keeping effect. Besides, the materials affect the biochemical component contents in the stored tea and the order of the changes of these components were Vc> chloropsultshy>free amino acids> water extracts>carbohydrate> polyphenols and caffeines.

Abstract:The extraction conditions of pectin from Hongjiang orange peel were studied by salting-out and acid –hydrolysis methods and the product quality was analyzed. Al2(SO4)3 was found as the best precipitator and the optimal acid extraction conditions were shown as follows: the ratio of water to materials of 10:1, pH value of 2.0, temperature of 85 ℃, and extraction time of 120 min. For salting out of the extracts, the best volume of Al2(SO4)3 saturated solution, pH value, temperature and time were 5mL per 100g pectin extracts, 7.0, 75 ℃, and 60 min, respectively. The crude pectin was then desalted by the mixture of HCl, ethanol and water (VHCl/V乙醇/V水=47/50/3) for 30 min with its content of 20 mL/g pectin. Under those conditions, the yield of pectin was 6.70% with the galacturonoglycan content, methoxyl content and gelatination degree being of 47.3%, 33.3% and 109, respectively.

Abstract:Changes of total acid, pH value, soluble solids, VC, total sugar, reducing sugar, protein and amino acid content of green pepper and Chilli during the inoculated fermentation process were investigated in the experiment. The result indicated that green chill fermentation had the same typical characteristics with Chilli fermentation, which confirmed the feasibility of green pepper sauce via fermentation. Adding sugar or sugar-containing vegetables may improve the quality of the fermented sauce. Besides, improving the flavor and reducing the loss of chlorophyll was the key to the color retention of the green pepper sauce.

Abstract:Pectin was extracted from banana peel by HCl and its effect on the stability of yogurt was investigated. The optimum extraction conditions were as follows: pH value of 2.0, temperature of 80 ℃, extraction time of 1.5 h and the ratio of liquid to solid of 4:1. Orthogonal experiment showed that the most stable yogurt was achieved using 0.3% stabilizer (xanthan gum:banana peel pectin=1:3) under the following fermentation conditions: temperature of 42 ℃，fermentation time of 3.5 h and inoculum size of 4%.

Abstract:The characteristics of acid protease produced by M. purpureus mutant W1 were preliminarily studied. The optimum reaction temperature and pH value of this acid protease were found to be 50 ℃ and 3.0, respectively. And the enzyme showed high stability within the temperature ranges of 30~40 ℃ and with the pH value of 3.0~5.0. It was also found that the activity of the protease could be inhibited by Fe3+, Al3+, Mg2+, and Cu2+, and activated by Mn2+, Ag+, and K+. The molecular weight of this protease was about 55000~60000 Da by Sephadex-G75 gel layer analysis and SDS-PAGE protein electrophoresis analysis.

Abstract:Crude Casein Phosphopeptides (CPPs) were isolated from Camembert cheese and purified by D-201 anion-exchange resin. The CPPs extracted from Cheese showed higher activity to prevent calcium precipitate than that of the commercial CPPS.

Abstract:The microencapsulation of zanthoxylum essential oil was studied by ultrasonic wave using β-cyclodextrin (β-CD) as wall materials. Orthogonal design showed that the best ultrasonic power, temperature, ultrasonic time and the ratio of essential oil to β-CD were 200 W, 35 ℃, 30 min, and 1:5, respectively. Under those conditions, the encapsulation rate reached 80.1%. This method was simple and efficient, suitable for the microencapsulation of essential oil using β-cyclodextrin.

Abstract:The processing technology of high protein powder was studied using wasted yolk powder as materials. The results showed that the best ethanol extraction conditions were as follows: the ratio of ethanol to yolk power of 1:3, temperature of 40 ℃, extraction time of 4 h and batch blending.

Abstract:The best preparation technologies of peanut tofu were studied in this paper. Peanut was baked for 5 min with the baking power and frequency of 450 kW and 2450 MHz, respectively, and then was grinded with soybean (1:4) by adding 5 times of water. Then 0.25% of GDL and 2% of starch were added to the formed milk, giving the product peanut tofu which was rich in nutrition and had nice taste.

Abstract:The establishment of HACCP system in food service industry, the final step of food consumption, will improve the level of food safety control. The establishment of HACCP system of food service industry was studied in this paper, and the critical control points (CCPs ) were determined by the hazard analysis. The given HACCP program provided a good sample of HACCP system in food service industry.

Abstract:Enzyme-Linked Immunosorbent Assay (ELISA) is a sensitive, convenient and economical immunoassay technology established on the combination of the highly specific antigen-antibody reaction. In this paper, this technology was briefly introduced, and its application in quality analysis of condiments was commented in detail, including pathogenic microorganism contamination, biotoxins, forbidden organic compounds and food allergens. The application prospects of ELISA in the quality control of condiments were also presented.

Abstract:The Most Probable Number Methods (MPN) of Food Trade Standards were employed to enumerate the total bacteria count, MPN, faecal coliforms, Vibrio parahaemolyticus, Staphylococcus aureus and Salmonella in the process simulation of Meretrix meretrix Linnaeus from the offing of Donghai Island (Zhanjiang, China). The results showed that the treatments of cleaning and scalding with hot water and freezing for 0.5 h showed a little effect on the total bacteria count of the raw material of M. meretrix which was (4.0±0.1)×105 cfu/g. It was also found that cleaning and scalding with hot water markedly reduced the MPN of the raw material of M. meretrix from (790.7±21.3) MPN/g to (19.4±1.3) MPN/g, and a further freezing treatment (0.5 h) decreased the value to (18.3±1.1) MPN/g. Faecal coliform of the raw material of M. meretrix was (817.5±19.8) MPN/g, which markedly fell to (194.2±10.2) MPN/g by cleaning and dipping into thermal water and to (180.6±11.3) MPN/g by further freezing for 0.5 h. V. parahaemolyticus in the raw material and the processed M. meretrix was less than 3 MPN/g. Besides, no coagulase-positive S. aureus and Salmonella were found in every products of the simulatively processed M. meretrix. M. meretrix in the offing of DonghaiZhanjiang was mainly contaminated by coliform strains and faecal coliforms which can be significantly eliminated by cleaning and dipping into thermal water then freezing for 0.5 hours.

Abstract:A method for determination of organochlorine compounds (OCLs) and polychlorinated biphenyls (PCBs) in dry fish by GC was established. OCLs and PCBs were extracted by automaticity soxhlet extraction, purified by Florsil PR solid phase extraction (SPE) and analyzed by GC-ECD using Mirex as the internal standard on DB-1701 and SPB-1 columns. The results showed that 16 kinds of OCLs and PCBs were separated by GC. Within the linear range of 0.02 mg/kg~0.50 mg/kg, the coefficient of variation for repeatability, relative standard deviation for reproducibility and the detection limit of the method were 0.44%~8.73%, 0.15%~7.90% and 0.03~0.1 g/kg, respectively.

Abstract:The essential oil in the outer yellow and inner white peels of Citrus Grandis Planted in Jiangyong (Huan Provience) was extracted by steam distillation. GC-MS analysis showed that 61 and 22 kinds of compounds existed in the essential oil in the outer yellow and inner white peels, respectively. The main components in the essential oil of outer yellow peel were hydrocarbons, among which limonene was found with high content of 76.04%. In white peels, octadecadienoic acid, hexadecanoic acid, and ethylene oxide heptamer were found to be the main compounds.

Abstract:A method was developed for the determination of biphenol A, alkylpheniols and alkylphenol ethoxylates residues in nursing bottle by HPLC-RF. Samples were extracted by dichloromethane- methanol, and analyzed by HPLC-RF. The linear range of BPA, OP, NP, OPEO were within 0.05~1.0 µg/mL and that of NPEO was within 0.2~1.0 µg/mL. Recovery rates of these compounds in nursing bottle ranged from 81.1% to 100.3%, and the relative standard deviations were of 2.7%~5.5%. The detection limits of the method was: BPA 1 mg/kg, OP 2 mg/kg, NP 2 mg/kg, OPEO 2 mg/kg, and NPEO 5 mg/kg. This method was simple, sensitive and precise, which was suitable for qualitative and quantitative analysis of BPA、AP and APEO residues in nursing bottle.

Abstract:In this paper, the research trends of γ-amino butyric acid (GABA), including its healthy functions, metabolic pathway, and extraction, were reviewed. The application prospects of GABA were also discussed.