Abstract:As one of the essential amino acids for human beings and animals and one of the first restrictive amino acids for human and plants,L-lysine has many functions,such as balancing amino acid composition,adjusting in the body metabolic balance,accelerating the rate of absorption of protein,promoting the growth and development of animals,improving the utilization of protein.It takes around 4 mol NADPH to produce 1 mol L-lysine.However,it takes around 1 mol NADPH to produce 1 mol L-glutamic acid.Therefore,the improvement of NADPH in the pathway of L-lysine fermentation is one of the key factors to increase the output of L-lysine.This paper stated the research evolution focus on aspects of the L-lysine biosynthetic pathways of Corynebacterium glutamicum,the metabolism of NADPH and the NADPH-metabolizing enzymes.

Abstract:A strain producing red-pigment was newly isolated under poor nutrition conditions.It was identified by 16S rDNA sequence and systematic analysis,as well as general morphological and biochemical characteristics,The results show that 16S rDNA sequence of the strain suggesting that the strain is Serratia marcescens Species.And it was named Serratia marcescens JNB5-1.The red-pigment was identified as prodigiosin by wavelength scanning and LC-MS.preliminary fermentation conditions of strain Serratia marcescens JNB5-1 was studied.The results showed that the yield of prodigiosin was improved to 4.139 g/L after 72 h in the medium:sucrose 2%,beef extract 1.5%,CaCl2 1%,proline 0.75%,MgSO4·7H2O 0.02%,FeSO4·7H2O 0.006%.

Abstract:The aim of this research was to investigate the impact of extracellular oxidoreduction potential(ORP) on lactic acid production in batch culture by Lactobacillus paracasei.The ORP control was conducted by regulating the ratio of air flow rate to nitrogen flow rate in the inlet aeration of fermentor.As the results shown,the high ORP levels(the inlet air 1.5 L/min,-100mV,-150mV) resulted in higher lactic acid production but lower sugar-lactic acid conversion ratio,and the biomass was more than two times than that in the low ORP conditions(-200 mV,-300 mV,the inlet nitrogen 1.5 L/min).The highest lactic acid production(153 g/L) was obtained at the ORP level of-100 mV.The highest lactic acid yield(100.3%) was obtained at ORP level of-200 mV.Further more,the impact of ORP on the intracellular redox potential(NAD+/NADH) was investigated.

Abstract:To avoid leaving numerous waste in the processing of grass carp,the processing technology of fish and mushroom paste with salted fish cubes,mushroom,soybean and fermented soybeans has been studied.The important factors,such as the amount of pi xian bean paste and allspice,the intensity of sterilization,on the quality and flavor of the product in processing,were studied by single factor experiment and Orthogonal experiment,and the optimum formula was achieved according to the result of experiments.And then,the characteristics of product’s quality were valued by Texture analyzer and the optimum processing technology of fish cubes was achieved.Finally,Volatile flavor compounds of product were extracted with solid phase micro-extraction(SPME) apparatus and analyzed and identified by GC-MS,and characteristic volatile flavor compounds of the product was identified.

Abstract:A combined headspace solid-phase microextraction(HS-SPME)with gas chromatography-mass spectrometry(GC-MS)method has been employed for the analysis of the cooking flavor volatiles of rice.The rice were storaged by different packing ways(natural hermetic storage,filling with carbon dioxide or nitrogen and vacuumizing storage)under the following conditions:temperature 37 ℃,relative humidity 60%.The research showed that the augmentel of aldehydes,alcohols and ketones was the most prominent by natural hermetic packing than other packing ways after storage.Through comparing the total alcohols,aldehydes,ketones and 2-pentylfuran of vacuumizing storage,filling with carbon dioxide and nitrogen,it was found that storage of vacuumizing and filling with carbon dioxide could postpone the deterioration of rice flavor volatiles and keep the quality of rice.

Abstract:In order to understand the contamination of Pseudomonas aeruginosa(PA) and bromate in mineral water before and after the implementation date of national standard for natural drinking mineral water(GB 8537-2008),and to analyse the contamination reason,PA and bromate,in mineral water samples,were respectively detected using filter membrane methods and Ion chromatography which based on the national methods(GB /T8538-2008 /54 and GB/T 5750.10-1995).It was found that,during 2008.01~2009.10,the positive rates of PA in both source water and finished water were respectively 11.43% and 35.42%,and that of bromate in finished water was 42.12%.However,during 2009.10~2010.09,the values of the three were 30.30%,17.65% and 18.10%,respectively.The PA contamination in the finished water could be respectively attributed to the producing process and the pollution of the source water.Thus,there still exist the excessive PA and bromate in mineral water after the implementation of GB 8537-2008.

Abstract:An electronic nose(E-nose) was developed to distinguish different grades of Jinhua hams through detecting the aroma of three types of Jinhua ham samples to obtain the response value respectively.Then the data was analyzed by using Principal Component Analysis(PCA),Linear Discriminant Analysis(LDA) and Partial Least Squares(PLS).LDA was used for identification,PCA for dimensionality reduction and PLS for prediction.Results showed that electronic nose can distinguish different grades of Jinhua hams.The method was confirmed in prediction of Jinhua hams with different grades.The research will provide an important scientific knowledge to improve and perfect the national standard of Jinhua hams in future.

Abstract:To investigate the distasteful substance in bayberry juice,the aromatic components in juice of bayberry were extracted by SPME and analyzed by GC-MS.By comparing the two samples,the reasons for the bayberry juice’s off-flavor was listed as follows: the reduction of esters and trans-Caryophyllene;the increasing of ethanol and 1-butanol,3-methyl-,which have an alcoholic odor;the increasing of 1-nonene and hexanoic acid,which have a rancid odor;the increasing of aldehydes for polyphenol oxidase and lipid oxidation.

Abstract:To investigate the antioxidant effects in vitro and in vivo of Inonotus obliquus total flavonoids(TFIO),the radical scavenging capacity of TFIO and its inhibiting effect on lipoxidase activity were evaluated by the DPPH· model and the lipoxidase system,respectively.Meanwhile,the inhibitory action on hemolysis of mice RBC(red blood cell) by H2O2-induced was detected by spectrophotometry method,the effects in vitro and in vivo of TFIO on the formation of MDA(malondialdehyde) and ROS(reactive oxygen species) in mice liver were detected by the reagent kits.The results showed that in vitro,4.00 mg/mL TFIO showed 76.77% scavenging rate on DPPH·radical,81.73% inhibiting rate on lipoxygenase,83.33% inhibitory rate on mice RBC hemolysis by H2O2-induced,36.73%(non-induced),20.34%(Fe2+-induced) and 48.59%(H2O2-induced) inhibiting rates on MDA formation in mice liver homogenate,respectively,it also significantly increased the anti-ROS unit of mice liver homogenate to 50.75 U/mL(P<0.01,vs control group).In vivo,the MDA value reduced significantly(P<0.01,vs control group) and inhibiting rates of MDA formation reached 48.52% and 58.52% in mice liver after they were continuously treated by intra-peritoneal injected with 0.5 and 2.0 mg/mL TFIO(0.04 mL/(g·d),11 d),respectively.Therefore,it can be clearly seen that TFIO have strong antioxidant effect in vitro and in vivo.

Abstract:Research on microwave vacuum drying of Chinese yam was carried out by using a microwave vacuum drying equipment.The thin layer microwave vacuum drying model of Chinese yam was established by analyzing the relationship between moisture ratio and time of experimental data.The results indicate that moisture ratio was linear before the moisture content of materials was 50% in the microwave vacuum drying.The prediction model of moisture ratio was MR=(0.103 225 3P-1.628 6×15-5W-0.009 729 556)(1/(0.089 295 9P-1.566 473×10-5W-0.010 239 25)+t).The model could describe and predict change regulation of moisture ratio very well according to the comparison of experimental values and calculated values.

Abstract:The inhibition effects of 6 kinds of chinese herbal extracts against fungi(Mucor and Penicillium) causing decay on postharvest peach were studied in this paper.The 6 kinds of chinese herbal were glycyrrhiza,alpinia officinarum,phellodendron,asiatic moonseed,leaf of moxa and forsythia.The antibacterial effects of different chinese herbal extracts were comparatived by growth rate method and inoculation of spore suspension on peaches.The species of chinese herbal which had good inhibitory effects were selected.And the minimal inhibition concentration(MIC) and minimal bactericidal concentration(MBC) of chinese herbal which had good inhibitory effects were investigated by dilute with grads.The results showed that:different chinese herbal extracts had different inhibitory effects against fungi causing decay on postharvest peach.Glycyrrhiza and forsythia were the better kinds which against the Mucor and Penicillium in these 6 kinds of chinese herbal.Alpinia officinarum and phellodendron were the kinds with general inhibition.Leaf of moxa and asiatic moonseed were the weak inhibition kinds.The MIC of glycyrrhiza and forsythia extracts on Mucor all were that amounts of extracts in medium(v/v) were 25%,the MBC of glycyrrhiza and forsythia extracts on Mucor were 50%.And on Penicillium,the MIC of glycyrrhiza and forsythia extracts all were that amounts of extracts in medium(v/v) were 12.5%,the MBC of lycyrrhiza and forsythia extracts on Penicillium were 25%.

Abstract:The optimal process of frozen noodle and the influence of guar and xanthan gums and their combined use on frozen noodle textural and calorimetric properties was investigated.We find the optimum water added is 36%,the optimum salt added is 2.5%,the optimum proofing time is 50 min,the optimum poach time is 2.5 min;And the result indicted that xanthan and guar gum addition increased the maximal breaking force of frozen noodles attributed to improveing gluten matrix.However,only xanthan gum addition reduced the fusion enthalpy in comparison to the control fromulation(169.05 J/g to 151.32 J/g for formulation with xanthan gum and 170.68 J/g to 152.24 J/g for formulation with both gums).Whereas,reduction in the content of freezable water is 11.9%、16.9%、15.9% for formulation with guar and xanthan and their bombied gums respectively.

Abstract:Purpose: To investigate the separation method and the structure of polysaccharides with hypoglycemic effect from barley malt(BP).Methods: Alloxan-induced diabetic mice model was built,in which the hypoglycemic effect of polysaccharides from barley malt were determined.The polysaccharides from barley malt was purified to homogeneity through DEAE-cellulose,HW-55F and Sephacryl S-400 column chromatography.Meanwhile,the purity identification was analyzed by phenol-sulfuric method and thin layer chromatography.The structure was investigated using sugar composition analysis and 1H-NMR,13C-NMR,135DEPT-NMR analysis.Results: The polysaccharides can decrease fasting plasma glucose of the diabetes mice efficiently,and showed no significant effect on postprandial plasma glucose.Neutral polysaccharides(NBP)and acidic polysaccharides was isolated by DEAE-cellulose.BPⅠ and BPⅡ were further isolated from NBP by HW-55F and Sephacryl S-400.BPⅠconsists only of glucofuranose units joined by 1→3 bond,and both of α and β-configuration appear alternately.The main chain of BPⅡ is galactoses linked by 1→4 bond,and the galactose,forming lateral chain,is linked to C-6 of galactose in the main chain.BPⅡ is reported for the first time from barley malt.

Abstract:The ultrasonic extraction process of polysaccharides from Pleurotus geesteranus was optimized by response surface analysis,and the antioxidant activity of the extracts were determined.The results showed that,the optimum ultrasonic extraction conditions were obtained as follows:temperature at 40 ℃,ultrasonic power at 400 W,time duration for 114 min,and the ratio of solution(water) to solid(fruit body powder) of 30∶1.Under this condition,the extraction yield of the polysaccharide from Pleurotus geesteranus was 60.19 mg/g,which was consistent with the predicted value(60.74 mg/g).The Polysaccharide extracts have a certain extent function to scavenging hydroxyl radical.Their antioxidant power and the reducing capacity increased with the increase of polysaccharides concentration.

Abstract:A lab Far-infrared vacuum dryer was designed and fabricated.The temperature changes during the process of far infrared vacuum drying were investigated taking carrot slices as test material.The mathematics model of temperature change for drying of carrot slices was established and validated.

Abstract:The aim was to screen a cold-active elastase producing strain and study the enzymatic properties in order to establish the theoretical basis for its application of meat tenderization.One strain,named XZE116,which produced cold-active elastase was screened using elastin as sole nitrogen source on elastin agar plate according to the ratio of the diameter of the hydrolytic circle to the diameter of the colony.The strain was identified as Bacillus brevis by morphological,physiological,biochemical tests and 16S rDNA gene sequence analysis.The enzyme was highly active over a wide range of pH from 7.0 to 12.0,with an optimum at pH 8.0.It exhibited maximal activity at 25 ℃ and was stable within two hours below 40 ℃.The enzyme activity was activated by Mg2+,but was strongly inhibited by Hg2+ and Pb2+.Its activity was completely inhibited by phenylmethanesulfonyl fluoride(PMSF),but not by E-64,suggesting that the enzyme is a serine-protease.The elastase activity was slightly reduced by anionic(0.1% SDS),cationic(0.1% cetyltriethylammnonium bromide,CTAB),non-ionic surfactants(1% Tween-80 and 1% Triton X-100).Considering its promising properties,the elastase from Bacillus brevis XZE116 may find potential application in meat industry.

Abstract:On the basis of single factor experiments,initial pH,VB1,rotation speed and culture temperature were selected as independent variables to optimize liquid fermentation conditions of total triterpenoids from Poria cocos mycelium.Using RSM design analysis,the optimal liquid fermentation conditions were achieved and listed as follows:initial pH 5.45,VB1 7.3 mg/L,rotation speed 132 r/min,culture temperature 26.6 ℃.Under these conditions,the yield of intracellular total triterpenoids reached 7.06%,which increased about 35% than before.