In order to extract the high-purity sesamin, this paper researches isolation and purification of sesamin from sesame seed meal by means of macro-porous resin. Results indicated that AB-8 resin and HP-20 resin have much higher static adsorption rate and desorption rate for sesamin, which adsorption rates are respectively 9.24mg/g and 9.28mg/g, and the desorption rates are respectively 94.81% and 94.35%. By carrying on the dynamic adsorption and the desorption experiment with AB-8, the result indicates that the higher the sample concentration, the bigger the adsorption, and the less injection velocity is more advantageous to the adsorption. It’s a much better effect by using 95% ethyl alcohol desorption, and reasonable amount of desorption liquid is 10 times the volume of the column (BV), and if the elution speed is smaller, the higher content sesamin can be obtained by desorption. Taking everything into consideration, it is more appropriate to select injection velocity and elution velocity for 1.0ml/min. The purity of sesamin is from crude extract of 12.88% up to 70.56% by macro-porous resin purification.

Ultrasonic radiation was used to assist the extraction of red pigment from grain amaranth flower spikes, effect of solvent，material/liquid ratio ，extraction temperature ，ultrasonic intensity，extraction time and extraction degree to the result of pigment extraction was researched based on single factor experiments, BBD combined with response surface methodology(RSM) was employed to find a optimized extract method. Results showed: the optimal parameters was: material/liquid ratio was 1:46.5, extraction temperature and time was 32.8℃ and 67.2 min respectively，ultrasonic intensity was 150w and extraction degree was 2. In optimized conditions, the anticipative maximum extraction ratio was 82.13% and the result of demonstration test was 82.29%.

In an attempt to optimize lentil steeping and germinating conditions for γ-aminobutyric acid (GABA) enrichment, the individual effects of steeping time and temperature as well as germinating time and temperature on GABA synthesis in lentil were investigated by single factor and orthogonal experiment. The optimum conditions for lentil were obtained as follows: steeping time 2.5 h, steeping temperature 36℃,germinating time5h,germinating temperature 24℃,and under the optimal conditions, the GABA content in lentil reached 380.503mg/100g which was 1.9 times higher than that in the untreated one.

In this study，optimum condition of ultrasonic-assisted extraction of locust bean gum (LBG)is optimized by response-surface test．On the basis of single-factor test，the mathematical regression model is established about the dependent variable (extraction yield of locust bean gum)and independent variables(ratio of material to water，extraction temperature，extraction time and ultrasonic power)through Box-Benhnken center composite design and response surface methodology．The optimum extraction conditions as follows：material to water ratio 1:47 (g?mL-1)，extraction temperature 43 ℃，time 63 min，ultrasonic power 800 W．Under these conditions，the yield of locust bean gum is 28.03%．The locust bean gum products meet the FCC Ⅳ standards．The structural is identified using infrared spectrum.

Purpose: To optimize the enzymatic-assisted extraction process for polysaccharides from Truffles to improve extraction efficiency. Methods: Based on the single-factor experiments, the Box-Behnken center-united experimental design principles for 4 factors were used to determine the experiments condition and the response surfaces analysis. Results: Within the tested level ranges, the impact of three process parameters on extraction yield of polysaccharides from big to small was pH, enzymatic time, enzymatic temperature and enzyme dosage in turn. The optimum extraction pH was 5.6, enzymatic temperature was 61℃, enzymatic time was 65min and enzyme dosage was 1.6%. The predictive maximum yield of polysaccharides extraction rates was 15.00% and the polysaccharides content was 74.19, the average yield of polysaccharides in three validated experiment under the optimized process conditions was 14.31% and the relative error was 4.60% , the actual content was 74.96% and the relative error was 1.04%. Conclusion: Enzymatic assistance is beneficial to briefness methodology ,convenient operation and improve extraction efficiency and consequently, suitable for the extraction of polysaccharides from Truffles.

As the oxidation of polyphenols for the polyphenol oxidase is thought to be the major cause of the browning of banana during its storage and processing, the optimal extracting conditions of the polyphenol oxidase from banana was found through the homogenate extraction with the herbal blitzkrieg extractor, so as to research the characteristics of the polyphenol oxidase from banana to improve the utilization of banana. The initial seven factors (source of buffer solution, ionic concentration and pH of solvent, liquid:solid ratio, time, concentration of polyvinylpyrrolidone(PVPP) and polyethylene glycol octyl phenyl ether(Triton X-100)) with at least six levels were optimized by single factor experiment depending on the response of enzymatic relative activity. Then four factors plus their best levels were chosen to optimize the extraction using a Box-Behnken design experiment with the Design Expert 8. It revealed, through the response surface methodology, that the optimal extraction conditions were source of buffer solution (Phosphoric acid-citric acid) without potassium chloride, pH (5.58), liquid:solid ratio (1.57), PVPP concentration (1.13%), time (2.5min).

Response surface analysis methodology (RSM) was applied to optimize the ultrasonic-assisted extraction conditions of total flavonoids from Malus hupehensis. The concentrations of ethanol in solvent, extraction time, ultrasonic power and ratio of liquid to solid were chosen as casual factors. Base on the single-factor experiments four-factor-three-levels box behnken experiments design were applied. RSM was employed to study on the effect of these factors on the yield of total flavonoids from Malus hupehensis. The results show that the optimum ultrasonic-assisted conditions were ratio of liquid to solid 50:1(mL/g), 67.35 % ethanol, extracting time 3.2 h, ultrasonic power 162.4 W, Validation experiments were carried out at these optimum conditions. The predicted value of the maximal yield of flavonoids is 12.78 %, while the effective value is 12.76 %, the relative error between actual values and predicted values is 0.02 %. These results demonstrated that the method is feasible.

An analytical method was developed to simultaneously determine chlorine dioxide（CLO2）and its degradation byproducts chlorite(CLO2-) and chlorate (CLO3-) in fresh meat by Ion Chromatography(IC). Sample preparation was extracted by 0.05mol/L phosphate buffer-acetonitrile solution( pH 4.3,50:50)，adjusting the pH value around 7~8 and eliminating impurities by calcium hydroxide solution, removing lipids with N-hexane. The optimum condition was achieved by separation on a AS11-HC column, eluting by 15 mmol/L KOH solution at a flow rate of 1.0mL/min, determinating by conductivity detector and external standard. The detection limit of CLO2-，CLO2，CLO3- were 0.7mg/L,0.5mg/L,0.5mg/L，limit of quantitation were 1.2mg/L,1.0mg/L,1.0mg/L. It was the first time using Ion Chromatography to detect the residues of CLO2-、CLO2、CLO3- in fresh meat with good accuracy, reliability and practicality.

The determination of trace elements in food leavening agents NaHCO3 including Be, Mg, Al, Ca, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, Hg and Pb by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) has been investigated. Samples were decomposed by HNO3 followed by dilution with ultrapure water then the above 14 elements in the solution was analyzed directly by HR-ICP-MS. To overcome some potentially problematic spectral interference, measurements were acquired in both low and medium resolution modes. The internal standards of Ge, In and Bi can significantly improve the long time stability and precision level of determination. The method was shown to be very sensitive with limits of quantification in the range of 0.008～21.62 μg/L for all investigated elements, the recovery of the samples was in the range of 92.60%～110.00% and the relative standard deviation(RSD) less than 2.39%.

Chrysanthemum flower is a kind of Chinese traditional herb and contains volatile oil and flavonoids as its active ingredients. The extracted volatile components of Chrysanthemum flower were analyzed and identified by means of comprehensive two-dimensional gas chromatography (GC×GC)/time-of-flight mass spectrometry (TOFMS). Totally 156 volatile components with similarity of more than 850 were identified in this study.

Analysis of Models for Main Potato Nutrients Content Based on Near Infrared Spectroscopy ZHANG Xiao-yan, YANG Bing-nan*, LIU Wei, ZHAO Feng-min, YANG Yan-chen, XING Li (Chinese Academy of Agricultural Mechanization Sciences, Beijing 100083, China) Abstract: With 44 different potato cultivars as the material, Principal component analysis (PCA) was used to select four indicators (water, reducing sugar, starch and protein) which can cover most information of potato samples. Predicted mathematic models for analysis were established and evaluated with partial least square (PLS) method. The accuracy of models was estimated by the determination coefficients (R2cal), relative predictive determination (RPD) and the root mean square errors of calibration (RMSEE), the determination coefficients (R2cv) and the root mean square errors of cross validation (RMSECV). For the calibration model of water, R2cal =98.37%, RMSEE=0.445, RPD=7.84; for the cross validation model of water, R2cv=93.05%, RMSECV=0.84, RPD=3.79. For the calibration model of reducing sugar, R2cal = 98.43%, RMSEE= 0.0236, RPD= 7.99; for the cross validation model of reducing sugar, R2cv= 86.42%, RMSECV= 0.0598, RPD= 2.71. For the calibration model of starch, R2cal = 97.13%, RMSEE= 0.577, RPD= 5.9; for the cross validation model of starch, R2cv= 95.370%, RMSECV= 0.7, RPD= 4.65. For the calibration model of protein, R2cal = 98.41%, RMSEE= 0.0334, RPD= 7.92; for the cross validation model of protein, R2cv= 89.49%, RMSECV= 0.0767, RPD= 3.08.

Paralytic shellfish poisoning (PSP) toxins is an important risk for sea food safety, and detecting technology of high performance liquid chromatography (HPLC) for PSP toxins is an important part for promoting safety supervision system of sea food in China. In this paper, effects of post-column derivatization condition on reaction fluorescent intensity and mobile phase condition on separation of gonyautoxins (GTXs) base on HPLC were discussed. Analysis of post-column derivatization showed the effects of pH of reaction solution, reaction temperature, formamide concentration and ammonium formate concentration on fluorescent sensitivity of individual GTX compounds were remarkable different. Considering the relationship between reaction fluorescent intensity and reaction conditions, the optimum post-column derivatization conditions were defined as: reaction solution mixtured by 70 mmol/L periodic acid and 0.12 mol/L potassium hydrate, 0.75 mol/L formamide of 20% ammonium formate solution, with pH of 7.3～7.5, flow rate of 0.8 ml/min, and reaction temperature of 50℃. Analysis of mobile phase showed the effects of methanol concentration, sodium heptanesulfonate concentration, pH, and phosphate concentration on separation of GTXs were all obvious, and the optimum mobile phase conditions were determined as: the concentrations of methanol, sodium heptanesulfonate, phosphate were 1%, 1.5 mmol/L, 10 mmol/L respectively, with pH of 7.3. Comparison to HPLC of oshima method, the response rate of GTX1, GTX3 and GTX4 increased to 4.7, 3.4 and 3.8 times, respectively, beside that of GTX2.

Abstract:Objective:To develop a fast, sensitive, accurate high-performance liquid chromatography(HPLC) with nano quantity analyte detector (NQAD) for the determination of D-xylose. Method: The chromatographic separation was achieved with an amino column using a mobile phase composed of a mixture of acetonitrile and water (73:27, V/V) at a flow rate of 0.8 mL/min. The NQAD drift tube temperature was set at 50℃ and the N2 pressure at 30psi. Result: The linear range of D-xylose was between 10μg/mL and 120μg/mL (R2=0.9998). The detection limit was 0.7μg/mL. The average spike recovery was 101.97%, with a relative standard deviation (RSD) of 0.88%. Conclution:This method is sensitive, accurate and repeatable, and thus it is suitable for the determination of D-xylose.

To develop a technique for detecting and identifying Salmonellla spp by using pyrosequencing technology. According to virulence-specific target gene sequence analysis, this study designed specific PCR primers and sequencing primers respectively for pyrosequencing, and pyrosequencing reaction conditions were optimized. The results show that this method is the traditional national standard method of enrichment as a precondition before, while eliminating the tedious process of post-biochemical validation, greatly reducing the detection time from 4 or 7 days to 16 hours and accuracy consistent with the traditional biochemical validation. The study established Pyrosequencing detection method is effective, fast, accurate and simple operation for fast food-borne pathogen detection and identification of precise opened up broad prospects.

Objective To establish a new rapid screening method for detection of E.sakazakii—cross-primer amplification combined with immuno-blotting analysis. Method On the basis of sequence analysis of the E. sakazakii 16S-23S rDNA internal transcribed spacer,specific primers and probe were designed, we developed cross-primer isothermal amplification method, using the immuno-gold standard test strip to test results. The specificity of the method was evaluated by 18 strains of E.sakazakii and 36 negative strains of Enterobacteriaceae.The sensitivity of the method was evaluated by testing the quantitative DNA,pure bacteria counted and the sample of adding other bacterial. Result The method established in this article is highly specific and sensitive. The limit of decetion is 100fg/test for the genomic DNA, 101 cfu/mL for pure bacterial culture. Conclusion The method is highly sensitive,specific, easy to operate and does not require any complex equipment. It is very useful for detection of E. sakazakii in the port or underdeveloped areas.

The volatile oil in Elaeagnus lanceolata Warb. apud Diels is extracted by water-steaming method. The extraction rate is 0.53%. The chemical compositions of the volatile oil have been identified with the optimum separating and analyzing conditions by means of the GC-MS. The result shows 31 compounds are separated. The represention rate of tot-al volatile oil is 83.9％. The major chemical compositions of volatile oil in Elaeagnus lanceolata Warb. apud Diels are 4-methyl phenol，pelargonic acid , linoleic acid , palmitic acid , Germacrene D，hydrocarbon etc. The antibacterial activity of volatile oil in Elaeagnus lanceolata Warb. apud Diels has been studied. It showed that it has high antibacterial activity against E. coli、St. aureus、and B. subtilis.

A solid extraction column was prepared with graphene as adsorbent. Analytical method for the determination of six sulfonamides was developed based on graphene solid-phase extraction (SPE) coupled with high-performance liquid-phase chromatography. Ultraviolet detection was used for qualitative and quantitative analysis at 270 nm. Factors that may influence the extraction efficiency including the kind of adsorbents, the kind and volume of eluent, pH of sample solutions and sample volume were optimized in detail. Under the optimized conditions, there was good linearity in the concentration range of 0.1-100 μg/L with the correlation coefficients of 0.990-0.997. Limits of detection were in the range of 6.3-21.1 ng/L (S/N = 3). The precisions of proposed method were in the range of 2.12-4.75%. The method was applied to the analysis of vegetable samples with recoveries of 78.5% -103.2%.

Abstract: In order to find the new parameters of edible quality for frying oil and to achieve rapid detection on the spot, the edible soybean oil from different areas were researched. Carbonyl value promulgated by the nation was taken as reference standard. The changes of pH value and conductivity were analyzed as carbonyl value exceeded the national standard during batch deep-frying. The results showed that the carbonyl value increased obviously, pH value decreased gradually, conductivity increased and then decreased slightly with the increase of frying time. After batch deep-frying 12h, soybean oil couldn't be used as food when carbonyl value had exceeded the national standard, pH value was 4.16, H+ activity was 100 times and conductivity was 5 times to the fresh soybean oil. There were obvious correlativity between carbonyl value, H+ activity and the frying time. The relationship between conductivity and the frying time, carbonyl value was significant generally. It suggested pH 4.20 was considered as a new expression parameter that could be used to identify the edible quality of fried soybean oil.

In order to investigate the volatile flavor components in a Chinese style traditional meat product, Harbin air-dried sausage, headspace (HS) solid phase micro-extraction (SPME) technique was employed to extract volatile flavor components. And then, volatile compounds were successfully separated and identified by capillary gas chromatography-mass spectrometry (GC/MS). A total of 28 volatile compounds were identified in this work, which included 14 hydrocarbons, 5 aldehydes, 4 esters, 2 phenols, 2 ethers and 1 alcohol. The formation of these volatile flavor compounds might be due to the addition of alcohol, spices, lipid oxidation, amino acid catabolism, microbial activities and the interactions among them. In this experiment，the predominant volatile compound in Harbin air-dried sausage samples was ethyl caproate, followed by ethanol, hexanal and ethyl butyrate. Some branched chain aldehydes including benzaldehyde, 3- methylbutanal and 2-methylbutanal were also detected and identified in Harbin air-dried sausage samples.

22 enzymes deactivated tea samples gathered form different regions of Chongqing, were microwave digested, and then detected their 32 kinds of mineral elements by ICP-OES and ICP-MS. Result shows quantity of 15 rare-earth elements vary obviously among samples from different regions, the other 17 elements’ content are in the range of several μg to several mg per kilogram. principal component analysis shows that the content of Y, Pr, Nd, Eu, Gd, Tb, Dy, Ho, Er, Fe in Yong Chuan samples are less than other samples; Sr, Al, Ca is found lowest in Ban Nan and Nan Chuan samples, while the highest in Yong Chuan and Rong Chang; samples of other regions were decentralize on the score chart. Then combined with cluster analysis, 22 tea samples was clustered into 6 with a certain degree of similarity during a certain same produing region. The study indicated that determining tea Origin characteristics by mineral elements is feasible. Rare-earth elements' content and Ca、Sr、Ba、Al provide major base to determine provenance of tea.

Abstract: Purpose: To establish the determination method of total flavonoids and hyperoside in leaves of Rosa davurica Pall..Method：UV-spectrophotometric method was applied to determine the content of total flavonoids at the wave length of 418 nm using rutin as reference substance. The content of hyperin was determined with high performance liquid chromatography(HPLC) using Shim-pack VP-ODS C18 (150mm×4.6mm,5μm) column and CH3OH-0.5% H3PO4 (45:55)as gradient elution mobile phase. The UV detection wave-length, the flow rate and the column temperature were 360nm,1.0 mL/min, 40℃ respectively. Result: Total flavonoids and hyperoside have shown good linear relationship in the range of 0.02～0.12mg/mL(R=0.9996)and 0.192~1.152μg(R=0.9993).The average recovery rate and RSD of total flavonoids and hyperoside were100.87%,100.36%, 2.79% and 2.26% respectively. Conclusion: The determination method offered in the paper is characterized with celerity，accuracy and easy operation, which is fit for the content determination of total flavonoids and hyperoside in leaves of Rosa davurica Pall..

The effects of protein degradation on the spoilage progress of chilled tilapia fillets were measured by proteolytic bacteria, proteolytic compounds, protein solubility, the SDS-PAGE change patterns of myofibrilar protein and sarcoplasmic protein. The results showed that: the changes of proteolytic bacteria, pH and amino nitrogen met well the protein degradation progress of muscle. When proteolytic bacteria kept less than 6.10 logCFU/g, pH was in week acidity, amino nitrogen stayed no many changes, and the SDS-PAGE pattern of myofibrilar protein and sarcoplasmic protein had no evident changes. While proteolytic bacteria increased equal and more than 7.60 logCFU/g, pH was in neutrality and week alkalinity, amino nitrogen increased rapidly, and the protein strip of SDS-PAGE pattern became outspread and breakdown, the protein degradation strengthened continuously. It was a very important spoilage indication in the SDS-PAGE pattern of myofibrilar protein when third strip in the region of 45→29 kDa disappeared, and new strips in the region of ≤29 kDa appeared. These results were provided a theoretical basis for further study on screening out specific protein during protein degradation to indicate the process of quality deterioration in fish.