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01 May 2010, Volume 31 Issue 9
Basic Research
Correlation among Particle Size Distribution and Color Parameters in Aqueous Ethanol Solution and Antioxidant Activity of Anthocyanin Extracts from Different Varieties of Litchi Pericarp
ZHOU Wei-jing,LI Shu-yi,SUN Zhi-da*,XIE Bi-jun
2010, 31(9):  1-5.  doi:10.7506/spkx1002-6630-201009001
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Anthocyanin extracts prepared from 9 varieties of litchi pericarp were compared for differences in particle size distribution in different concentrations of aqueous ethanol solutions and various color parameters such as L*, a*, b*, C* and h°. In the case of the extracts having different anthocyanin contents, the correlations among anthocyanin content, particle size distribution parameters and color parameters in 35% aqueous ethanol solution and maximum hydroxyl free radical scavenging rate or median effective concentration (EC50) were analyzed. Results indicated that Nuomici litchi pericarp anthocyanins dissolved in 35% aqueous ethanol solution showed the best particle size distribution (in the range of 2.48-6.51 μm) and the D50 and the specific surface area were 4.56 μm and 498.23 m2/kg, respectively. In addition, anthocyanin extracts prepared from different varieties of litchi pericarp revealed a significant difference in particle size distribution. Meanwhile, Nuomici litchi pericarp anthocyanins had the highest c* (110.27) and a* (87.12) values and Feizixiao litchi pericarp anthocyanins had the highest L*(94.86) and b* (98.79) values. The color of anthocyanin extracts prepared from different varieties of litchi pericarp changed from red to yellow. Correlations were observed among anthocyanin content, maximum hydroxyl free radical scavenging rate or IC50 and particle size distribution parameters and color parameters in 35% aqueous ethanol solution. Moreover, particle size distribution parameters exhibited a dominant effect on color parameters in 35% aqueous ethanol solution.

Effect of pH on Gelation Properties of Rabbit Myosin
WU Ye,XU Ke,XU Xing-lian*,NIU Lei
2010, 31(9):  6-11.  doi:10.7506/spkx1002-6630-201009002
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In order to investigate the effect of pH on water-holding capacity and water mobility of heat-induced gelation from rabbit myosin, gelation properties of rabbit myosin were characterized through determining relaxation time (T2) of water using low-field nuclear magnetic resonance (NMR), and water-holding capacity (WHC), hardness and ultra microstructure of the gel. NMR results indicated that relaxation time for immobile water (T22) and relaxation time for free water (T23) exhibited a decrease as the increase of pH, which suggested that the slow water mobility resulted from the increased number of negative charge in myosin. Principal component analysis results revealed that T22 and T23 relaxation time had strong correlation with WHC, hardness and diameter of the gel. A significant difference was observed between samples near pI points and other samples. Moreover, the number and distribution of surface charge exhibited an effect on curling and stretching of myosin molecules, and finally affected WHC, hardness and mesh diameter of the gel, while T2 relaxation time could reflect this tendency well.

Relationship between Fine Structure of Amylopectin and Digestibility from Cereal Starch
MIAO Ming,ZHANG Tao,MU Wan-meng,JIANG Bo,JIN Zheng-yu
2010, 31(9):  12-15.  doi:10.7506/spkx1002-6630-201009003
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The correlation between starch digestibility and fine structure of amylopectin was investigated in this study. Slowly digestible starch (SDS) fraction was positively correlated (r = 0.909, P < 0.05; r = 0.847, P < 0.05) with FrI (DP > 30) and FrII (13 < DP < 30), respectively, and negatively correlated (r = - 0.869, P < 0.05) with FrIII (DP < 13). Thus, the chain length distribution of debranched amylopectin exhibited a relationship with low glycemic index. These investigations revealed a molecular basis of fine structural variability in amylopectin for starch digestion property and could provide a strategy to develop raw starch materials with high nutritional value.

Quantitative Evaluation on Color of Orange Juice in China
HAN Yan,WU Hou-jiu*,DOU Hua-ting
2010, 31(9):  16-18.  doi:10.7506/spkx1002-6630-201009004
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Color is very important sensory feature of oranges and orange juice, which directly affects the choice of consumers. Color parameters of orange juice made from 94 kinds of orange samples collected from major orange production area in China were quantitatively determined using chromatic aberration method to establish the color database for color properties of orange juice in China. Statistical analysis indicated that color values of orange juice in China were over 36 points, which was higher and better than that of orange juice from USA and Brazil. An obvious difference in color values of orange juice from different varieties and production areas was observed, however, the color values of orange juice produced in different years didn t exhibit a significant difference (P > 0.05).

Screening of Bacteriostatic Materials in Egg-coating Preservative
ZUO Juan,MA Mei-hu*
2010, 31(9):  19-22.  doi:10.7506/spkx1002-6630-201009005
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Spoilage of fresh egg is mainly caused by microorganisms. The screening of egg-coating preservatives was evaluated through antibacterial effect. Escherichia coli and Salmonella were used as test strains to determine bacteriostatic effect on essential oil through filter paper or double dilution methods. Six kinds of plant volatile oil exhibited the inhibition effect on Escherichia coli and Salmonella according to the following order from strong to weak, cinnamon oil, ilex oil, perilla leaf oil, tea tree oil, eucalyptus oil and forsythia oil. Moreover, cinnamon oil, ilex oil and perilla leaf oil have been selected from six kinds of essential oil as the compound bacteriostatic material. The compound bacteriostatic formula was 0.6 mg/mL cinnamon oil, 0.4 mg/mL ilex oil and 0.3 mg/mL perilla leaf oil.

Basic Research
Stability of Antihypertensive Peptides from Egg White Protein to Chemicals and Enzymes
YU Zhi-peng,ZHAO Wen-zhu,YU Yi-ding,LIU Bo-qun,LIU Jing-bo*
2010, 31(9):  23-26.  doi:10.7506/spkx1002-6630-201009006
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The stability of antihypertensive peptides from egg white protein to chemicals was evaluated by Plackett-Burman design and its stability in mimic gastrointestinal environment was also investigated by determining angiotensin converting enzyme activity. Results indicated that pH, temperature, light illumination, stock peptide concentration, Pasteurization treatment, ultrasonic treatment and magnesium ions had no significant effect on the stability of antihypertensive peptides. However, the stability of antihypertensive peptides was sensitive to pepsin and trypsin. The activity of antihypertensive peptides decreased to 13.0 % and 4.0 % from 46.0 %.

Lethal Effect of Microwave Treatment on Bacillus subtilis var. niger Spores
HUANG Ming,HUANG Feng,ZHOU Xing-hu,XING Yue,ZHOU Guang-hong
2010, 31(9):  27-29.  doi:10.7506/spkx1002-6630-201009007
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In order to explore the thermal effect of microwave sterilization, lethal effects of microwave and water-bath heating treatments on Bacillus subtilis var. niger spores were compared at various heating temperatures and time. After the activation of Bacillus subtilis var. niger spores, the spore suspension at the concentration of 104 CFU/mL was prepared. Microwave and waterbath heating treatments were used for the sterilization of spores to evaluate the lethal rate. Results indicated that the lethal rate at 92 ℃ was higher than that at 85 ℃ for both microwave and water-bath heating treatments. At the identical condition of heating temperature (85 ℃) and time, the lethal effect of microwave treatment was much better than that of water-bath heating treatment, which was due to an obvious non-thermal effect. However, no obvious difference in lethal rates of microwave and water-bath heating treatments at 92 ℃ for 20 min was exhibited.

Effect of Dynamic High-pressure Microfluidization on Morphology of Soluble Soybean Polysaccharides
ZHANG Wen-qin1,2,LIU Cheng-mei1,2,*,LIU Wei1,2,WAN Jie1,2
2010, 31(9 ):  30-34.  doi:10.7506/spkx1002-6630-201009008
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The effect of dynamic high-pressure microfluidization (DHPM) treatment on compositions, morphology, component change of sugar and molecular weight of soluble soybean polysaccharides (SSPS) were investigated. Results showed that soybean soluble polysaccharides were treated by DHPM, and then purified by DEAE-cellulose ion exchange column to obtain two components, which were SSPS-1 and SSPS-2. High performance gel permeation chromatography (HPGPC) analysis exhibited that SSPS-1 was a heteropolysaccharide containing a small amount of protein and SSPS-2 was a homogeneous polysaccharide associated to protein with high molecular weight. The molecular weight of SSPS-1 was reduced from 733 to 511 kD by microfluidization treatment. Scanning electron microscopy observation of SSPS-1 showed that feature of DHPM-treated SSPS-1 sample was changed from the disordered flake-like to ordered "match stick"-like structure, which swelled into sphere at the end of structure. The major components, Rha and GalA, in the main chain of SSPS-1 exhibited a decrease by 9.4% and 17.1%, respectively. While the components such as Ara, Gal, Fuc and Man in side chain of SSPS-1 exhibited a significant reduction, which were decreased by 14.3%, 26.3%, 41.7% and 60%, respectively. There were no detectable Xyl, Glc and GlcA due to the break of chains and hydrolysis.

Basic Research
Effect of Transglutaminase on Gel Properties of Horse-mackerel Surimi
CHEN Hai-hua1,2,XUE Chang-hu1
2010, 31(9):  35-40.  doi:10.7506/spkx1002-6630-201009009
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The effect of transglutaminase (TGase) on gel properties of horse-mackerel surimi was evaluated in this paper. Effects of TGase addition amount, reaction time and reaction temperature on gel properties of horse-mackerel surimi were analyzed through the indicators of texture, whiteness, water-holding capacity and microstructure. Results indicated that the best gel property of horse-mackerel surimi was achieved under the condition of TGase for 80 U/100g surimi, reaction time for 5 h and reaction temperature at 37.5 ℃. A compacted and uniformed net structure was formed at this optimal condition through the examination of scanning electronic microscopy. Moreover, two-step heating strategy for horse-mackerel surimi gel preparation was better than one-step heating at 90 ℃ for 20 min.

Biological Stability of Natamycin Solution
GAO Yu-rong,WANG Xue-ping,LIU Yang
2010, 31(9):  41-44.  doi:10.7506/spkx1002-6630-201009010
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In order to better apply natamycin in food, effects of temperature, illumination, pH and inorganic salts on biological stability of natamycin solution were investigated. Results showed that natamycin solution at less than 100 ℃ exhibited strong biological stability. However, the heating treatment at 121 ℃ could result in the reduction of biological stability of natamycin solution. The inhibition activity of natamycin solution to bacteria was decreased to 62.15% while treated at 121 ℃ for 15 min and natamycin solution was completely inactivated after the treatment at 121 ℃ for 30 min. Natamycin solution was also sensitive to ultraviolet radiation and could be inactivated after UV treatment for 90 min. Moreover, fluorescent light radiation could also result in inactivation of natamycin solution to some extent and the complete inactivation of natamycin solution was observed under fluorescent light illumination for 10 days. Natamycin solution revealed relatively stable in the range of pH 4-8. No obvious effect of NaCl, MgSO4 and CuSO4 on biological stability of natamycin solution was observed, but FeCl3 and MgSO4 exhibited a significant effect on biological stability of natamycin solution.

Relationship between Pectin Content in Tomato Paste and Quality Characteristics of Tomato Powder
JIANG Jing1,WANG Zhong-min2,LI Jin-yu1,PANG Huan-ming1,ZHU Zheng-lan1,LI Huan-rong1,*
2010, 31(9):  45-48.  doi:10.7506/spkx1002-6630-201009011
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In this study, the relationship between pectin content and quality characteristics of tomato powder from spray drying was investigated using tomato paste as the raw material. The yield of tomato powder, microscopic characteristics and color change of tomato power from tomato paste with different pectin contents were evaluated. Results indicated that the yield of tomato powder was proportional to the pectin content of tomato paste under the identical condition of spray drying. The color change of tomato power exhibited a similar trend from red to reddish yellow, which revealed the gradually increasing L value and b value, and the declining a value. Tomato power with various pectin contents could provide more uniform particle size distribution and better dispersion due to the enhancement of pectin content.

Basic Research
Effect of Hypoxic Ventilation onγ-Aminobutyric Acid Content in Germinated Foxtail Millet
BAI Qing-yun1,2,ZENG Bo2,GU Zhen-xin2,*
2010, 31(9):  49-53.  doi:10.7506/spkx1002-6630-201009012
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In order to provide theoretical references for the deep development of millet, γ-Aminobutyric acid (GABA) accumulation in foxtail millet was explored through analyzing the change of major nutritional components and GABA content during the germination of millet. Dynamic changes of free amino acids, soluble proteins, glutamic acid, GABA content and glutamate decarboxylase (GAD) activity in germinated millet were investigated by the treatment of hypoxic ventilation. Results showed that sprout length of germinated millet were increased under hypoxic ventilation, however, the sprout length was still lower than that of the control; the content of free amino acids exhibited a rapid increase and higher than that of the control; the content of soluble proteins exhibited an initial increase and then a decrease, and lower than that of the control; an increase in glutamic acid content during first 24 h treatment of hypoxic ventilation and a following decrease were observed; GAD activity revealed a trend of initial increase and following reduction, and markedly higher than that of the control; GABA content revealed an increase during 48 h treatment of hypoxic ventilation and following decline. The maximal content of GABA was 24.32 mg/100g FW, which were 4.78 folds compared with pre-treatment, and higher 87.51% than the control at the same treatment time. These investigations indicated that hypoxic ventilation significantly improved GABA content of germinated millet, and GABA content exhibited a significantly positive correlation with free amino acids and GAD activity.

Suppression Effect of Compound Preservative on Spoilage Bacteria in Pickled Vegetables
JIANG Shao-tong,SUN Lei,LUO Shui-zhong,PAN Li-jun
2010, 31(9):  54-58.  doi:10.7506/spkx1002-6630-201009013
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Separation and identification of spoilage bacteria from pickled vegetables indicated that there were six dominant Grampositive bacteria including four strains of coccus, one strain of streptobacillus and one strain of bacillus. Meanwhile, the screening and optimization of bacteriostatic agents on spoilage bacteria were conducted. An obvious suppression effect of Nisin, sodium dehydroacetate or sodium Nipagin on spoilage bacteria was observed. Moreover, a compound preservative was optimized to be 0.4 g/L Nisin, 0.3 g/L sodium dehydroacetate and 0.2 g/L sodium Nipagin ester through orthogonal test. This compound preservative exhibited an excellent suppression effect on six strains of bacteria separated from pickled vegetables and common spoilage bacteria such as Staphylococcus aureus and Bacillus subtilis in food. The suppression rate could reach up to 96%.

Processing Stability of Red Pigment from Myrica rubra in Different Acidic Systems
XIA Hong,ZHU Qing-zhen,DING Jun-peng
2010, 31(9):  59-61.  doi:10.7506/spkx1002-6630-201009014
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Red pigment was extracted from fruits of Myrica rubra using 1, 0.1 mol/L and 0.01 mol/L hydrochloric acid, citric acid, tartaric acid and ascorbic acid. Different pigment solutions were obtained by filtration. Pigment solutions were subjected to heating treatment at 70 ℃ for 5 hours and ultrasonic treatment for 1 hour. The treated pigment solutions were placed in the natural light for 3 days. The absorbance change of pigment solutions was determined to evaluate the stability of pigment. Results showed that red pigment was not stable in acidic systems. The pigment was very unstable to heating, ultrasonic and light treatments in ascorbic acid system. However, the pigment exhibited relative stability to heating treatment in hydrochloric acid system with the minimum absorbance change in 1 mol/L hydrochloric acid. Moreover, the pigment also exhibited the relative stability to ultrasonic treatment in hydrochloric acid, citric acid and tartaric acid. Meanwhile, the minimum absorbance change of pigment after ultrasonic treatment was observed in 0.01 mol/L citric acid. Furthermore, the minimum absorbance change of pigment after natural light treatment was revealed in 0.1 mol/L hydrochloric acid.

Enzymatic-induced Gelation Properties of Protein Isolates from Phaseolus
CHEN Ling,TANG Chuan-he,ZHANG Ye-hui
2010, 31(9):  62-66.  doi:10.7506/spkx1002-6630-201009015
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Microbial transglutaminase-induced (MTGase) gelation properties of protein isolates from red kidney bean, red bean, mung bean and soybean (designated as KPI, RPI, MPI and SPI) were investigated. SDS-PAGE analysis and dynamic oscillatory measurement indicated that the time needed to gelation onset (tgel) exhibited a following order, KPI>MPI>SPI>RPI, whereas the order of G′ value after MTGase incubation was RPI>MPI>KPI>SPI. Protein solubility analysis of MTGase-induced gels suggested that electrostatic interaction, hydrophobic interaction and hydrogen bonds except covalent bonds were the primary forces responsible for the formation of gels. In addition, disulfide bonds were also involved in gelation. Therefore, compared to SPI, the effects of protein isolates from Phaseolus on gelation stability were less obvious due to the devoid of disulfide bonds among individual subunits in protein isolates from Phaseolus.

Effect of Glucono-δ-lactone on Functional Properties of Porcine Myofibrillar Protein
WANG Yu,KONG Bao-hua*,LI Ming-qing,XIA Xiu-fang,LIU Qian
2010, 31(9):  67-70.  doi:10.7506/spkx1002-6630-201009016
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The emulsion and gelation capabilities of myofibrillar protein (MP) during the addition of glucono-δ-lactone (GDL) at various concentrations (0.5%, 1.0%, 1.5% and 2.0%) were investigated. Results showed that the emulsion and gel capabilities were greatly improved by GDL (P<0.05) and no significant difference among different doses was observed. The whiteness of gel exhibited a decrease due to the increasing concentration of GDL. Meanwhile, the addition amount of GDL exhibited an obvious effect on water-holding capacity (WHC). No obvious effect of GDL with the addition less than 0.5% on WHC was observed; in contrast, a significant improvement of WHC was determined due to the addition of GDL ranged within 0.5%— 2.0%. In addition, the hardness, gumminess and resilience exhibited a reduction while the addition of GDL was ranged within 0.5% — 1.0% and then exhibited an increase while the addition of GDL was ranged within 1.5% — 2.0%. However, the adhesiveness exhibited a decrease at all conditions. Based on the comprehensive analysis, the best functional property of MP was achieved by the addition of 1.5% GDL.

Principal Component Analysis during Variety Screening for Instant Corn
LIU Yu-hua1,2,3,SONG Jiang-feng2,3,LI Da-jing2,3,LIU Chun-quan2,3,*,JIN Bang-quan1
2010, 31(9):  71-73.  doi:10.7506/spkx1002-6630-201009017
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Principal component analysis (PCA) was exploited in variety screening for instant corn, and the effective indicators for its processing quality were examined. Among selected 11 sweet-waxy corn varieties, major nutritional components affecting instant corn processing were determined. Results showed that the processing quality of instant corn was constituted by 3 principal components. Amylopectin exhibited the biggest contribution to processing quality of instant corn, which was account for 43.232%. Sushi 80618 and Jingtianzihuanuo No. 2 were selected and could be used for the preparation of instant corn.

Stability and Enzymatic Kinetics of Plantain Starch
XIA Yu1,XU Yong1,2,LI Yan-jie1,YUAN Gen-liang1,DU Bing1,YANG Gong-ming1,*
2010, 31(9):  74-79.  doi:10.7506/spkx1002-6630-201009018
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In order to provide theoretical references for the development and application of plantain natural resistant starch, the stability of plantain starch to heat, acid, alkali and amylase was investigated. Results indicated that principal constituent of plantain powder was starch with total amount of 78%. The plantain starch was one of ideal sources of natural resistant starch. Its initial, peak and final gelatinization temperatures were 72.10, 77.56 ℃ and 80.40 ℃, respectively. Its gelatinization enthalpy was 9.698 J/g. The maximum concentrations of plantain starch to resist acid and alkali were 0.001 mol/L and 0.01 mol/L, respectively. Based on the enzymatic hydrolysis curve of plantain starch, an enzymatic kinetic equation, V = 0.4426 × [S]/(6.566 + [S]), was deduced by the Wilkinson method, with Vm and Km of 0.4426 mg/(mL·min) and 6.566 mg/mL, respectively.

Experimental Studies on Freezing Points of Kiwi Peach and Pear
DONG Xiao-yong,LIU Bin*,SHEN Jiang,CAI Jing-hui
2010, 31(9):  80-82.  doi:10.7506/spkx1002-6630-201009019
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The detection of freezing point is a primary requirement to provide an effective strategy for the storage of fruits. The freezing points of kiwi peach and pear were tested by freezing method, and the relationship between freezing point and nutrition contents including reducing sugar, total sugar, total acid and soluble solid were analyzed. Results indicated that freezing point of kiwi peach was ranged from -1.9 to -2.6 ℃ and freezing point of pear was ranged from -1.4 to -2.7 ℃. Kiwi peach exhibited a higher content of total acid than that of pear, which reduced the effect of other contents on freezing point. However, the freezing point of pear was mainly affected by reducing sugar, total sugar and soluble solid. The calculated freezing points by regression equations derived from experimental data have a good consistency with experimental results, which can be used to guide the practical application during fruit storage.

Inclusion Identification between Chlorogenic Acid from Dandelion and Neutral Heteropolysaccharide from Bletilla striata
SHEN Qi1,2,SHEN Xiao-qing1,ZHANG Yang-yang1,ZHANG Wei-ming1,REN Yong1,3,WU Guo-rong1,3,*
2010, 31(9):  83-85.  doi:10.7506/spkx1002-6630-201009020
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Inclusion of chlorogenic acid (CA) from dandelion using neutral heteropolysaccharide of Bletilla striata (BSPS) was investigated in this paper. The inclusion was identified using differential scanning thermal analysis, infrared and 1H-NMR spectroscopy technologies. Results indicated that the inclusion was formed and the probable structure were deduced.

Extraction of Carboxylic Acid from Wine Using Fe3O4/SiO2 Nanoparticles Modified with Amino Groups
ZHU Yan-song,HAN Yan-dong,BAI Dan,XIN Guang
2010, 31(9):  86-88.  doi:10.7506/spkx1002-6630-201009021
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In this study, magnetic Fe3O4 nanoparticles were synthesized by chemical co-precipitation method, and aminomodified magnetic Fe3O4/SiO2 nanoparticles were obtained through adding SiO2 and APTES into Fe3O4 nanoparticles; the morphology and structure of pre- and post-modified Fe3O4/SiO2 nanoparticles by amino groups were characterized by infrared absorption spectrum (IR) and transmission electron microscopy (TEM). Gas chromatography-mass spectrum (GC-MS) was used to extract carboxylic acid from wine by magnetic amino-modified Fe3O4/SiO2 nanoparticles based on the reaction between carboxyl groups and amino group at normal temperature. These results demonstrated that magnetic amino-modified Fe3O4/SiO2 nanoparticles could extract carboxylic acid from wine with high efficiency.

Stability of the Pigment from Black Beauty Potato
LI Cai-xia1,YANG Xiao-long1,LI Qiong2,GAO Hai-ning1,ZHANG Yong1,*
2010, 31(9):  89-94.  doi:10.7506/spkx1002-6630-201009022
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In order to investigate physiochemical properties and stability of the pigment from Black Beauty potato, the change in maximum absorption wavelength of this pigment under different conditions was determined through a spectrophotometer. Results indicated that this pigment was a water-soluble anthocyanin. An obvious effect of pH on stability of this pigment was observed and this pigment exhibited better stability in acidic environments. In addition, Al3+ revealed an color enhancement effect on this pigment, while Na+, K+, Ca2+, Mg2+, Zn2+ exhibited little effect. In contrast, Cu2+ and Fe3+ contributed obvious adverse effects on stability. This pigment also exhibited strong resistance to radiation, but poor resistance to oxidation, light and heat. Although no obvious effects of sucrose at low concentration, VC and β-CD on stability of this pigment were observed, an enhanced effect of citric acid on pigment was observed. These investigations demonstrated exploitation and utilization values of this pigment in the industry of food additives.

Comparison on Nutritional Values and Textural Properties of Brown Rice and Milled Rice
YU Wei1,2,ZHOU Jian1,*,XU Qun-ying1,WANG Lan2,SUN Qi-fa1,CHENG Lin-juan1
2010, 31(9):  95-98.  doi:10.7506/spkx1002-6630-201009023
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Nutritional components in brown rice and ordinary milled rice was determined and compared to evaluate their nutritional values. Results showed that nutritional value of brown rice was higher than that of ordinary milled rice. The hardness of ordinary milled rice was higher than that of brown rice through the examination by texture analyzer. The gel strength of ordinary milled rice powder was higher than that of brown rice powder through the determination by dynamic rheometer. In addition, thermal properties of brown rice powder and ordinary rice powder were also analyzed using differential scanning calorimeter. The gelatinization temperature of brown rice (68.6 ℃) was higher than that of ordinary milled rice (62.4 ℃). The retrogradation of cooked milled rice powder (17210 Pa) was more obvious than that of brown rice powder (11350 Pa) while cooled at 20 ℃.

Effect of Xanthan Gum on Pasting Properties of Tapioca Starch and Paste Stability
ZHU Ling,GU Zheng-biao*,HONG Yan*,ZHANG Ya-yuan
2010, 31(9):  99-102.  doi:10.7506/spkx1002-6630-201009024
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In this study, effect of xanthan gum on pasting properties, viscosity stability and frozen-thaw stability of tapoica starch-xanthan gum paste under the conditions of acid and heat were investigated. Results indicated that the viscosity of tapioca starch exhibited an increase due to the increasing concentration of xanthan gum. The stability of starch-gum paste was significantly improved in acidic and heating environments. Electron microscope micrographs further confirmed that xanthan gum could improve pasting properties and stability of tapioca starch.

Antioxidant Effect of Celery Extract
WU Shao-mei,HA Jing,LIU Xiao-zheng,SHEN Fang,HAO Ye
2010, 31(9):  103-105.  doi:10.7506/spkx1002-6630-201009025
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Soxhlet extraction was used to extract flavonoids from celery. The antioxidant effect of celery extract was also investigated. The total antioxidant capacity and scavenging capability to free radicals were determined. Results showed that celery extract had strong anti-oxidation effect and scavenging capability to ·OH and O2·. The increasing concentration of celery extract resulted in an enhanced anti-oxidation effect and scavenging capability to free radicals. Ethanol extract from celery also exhibited an obvious effect on the prevention of oil oxidation, which was stronger than that of vitamin C.

Effect of Flavor Substances on Hydrogen Bonds of Water-ethanol System
ZHENG Fei-yun1,JIANG Tian1,DONG Jian-jun2,SHAN Lian-ju2,LI Qi1,*,GU Guo-xian1
2010, 31(9):  106-112.  doi:10.7506/spkx1002-6630-201009026
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The effect of major flavor compounds in wine on hydrogen bonds of water-ethanol system was studied. Plackett- Burman experiments confirmed that hydrogen bonds of water-ethanol system were greatly affected by isobutanol, β-phenylethyl alcohol, ethyl acetate, KCl, NaCl, MgSO4, malic acid, lactic acid and pyruvic acid. Correlation analysis indicated that coefficient between alcohol concentration and hydrogen bond intensity was 0.629. Therefore, alcohol concentration was the primary factor to hydrogen bond intensity although original wort concentration, isobutanol, Cl-, K+, pyruvic acid and lactic acid also exhibited an influence on hydrogen bond intensity to some extent.

Basic Research
Antioxidant Activity of Water-soluble Matrix from Abalone Shell
LIANG Hong-bao1,GUO Wei1,DONG Sheng-xiong1,WU Jiu-lin1,PENG Zhen-fei1,LIU Zhi-bin1,ZHANG Qi-qing1,2,*
2010, 31(9):  113-116.  doi:10.7506/spkx1002-6630-201009027
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The water-soluble matrix from abalone shell (WSMA) was purified by ion exchange chromatography (IEC) in DEAESephadex A-25 column. The antioxidant activity of WSMA was evaluated by scavenging capabilities of DPPH (1,1-diphenyl- 2-picrylhydrazy), hydroxyl (·OH) and superoxide anion (O2·) free radicals, and reducing powder of ferric ions. Compared with water-soluble matrix from pearl (WSMP) and vitamin C, WSMA revealed the similar reducing power and scavenging capability to O2· with WSMP, however, both WSMA and WSMP exhibited a weak inhibition effect on DPPH· and ·OH. The fraction from the second peak (AⅡ) separated by IEC was the major bioactive component. The scavenging capability of 1.0 mg/mL AⅡ to superoxide anion free radicals was 80%, which was equivalent to 0.1 mg/mL vitamin C.

Antibacterial Activities of PWE and PAE from Clematis songarica Bge. in Xinjiang
Gulibahaer·ABABAIKELI
2010, 31(9 ):  117-119.  doi:10.7506/spkx1002-6630-201009028
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Antibacterial activities of water extract (PWE) and alcohol extract (PAE, 70g/100mL ethanol) from Clematis songarica Bge. were evaluated. Results indicated that minimum inhibition concentrations (MICs) of PWE from leaves were 5g/100mL for Echerichia coli, 3g/100mL for Staphylococcus aureus and Bacillus pumilus, and 1g/100mL for Bacillus subtilis. MICs of PAE from leaves were 3g/100mL for Echerichia coli, 0.5 g/100mL for Staphylococcus aureus and Bacillus subtilis, and 1 g/100mL for Bacillus pumilus. MICs of PWE from stems were 10 g/100mL for Echerichia coli, and 7 g/100mL for Staphylococcus aureus, and 5 g/100mL for Bacillus pumilus and Bacillus subtilis. MICs of PAE from stems were 7g/100mL for Echerichia coli, 5 g/100mL for Staphylococcus aureus, and 3 g/100mL for Bacillus subtilis and Bacillus pumilus. MICs of PWE from flowers were 5 g/100mL for Echerichia coli, 3 g/100mL for Staphylococcus aureus and Bacillus subtilis, and 1g/100mL for Bacillus pumilus. MICs of PAE from flowers were 1 g/100mL for Echerichia coli, Staphylococcus aureus and Bacillus pumilus, and 0.5 g/100mL for Bacillus subtilis. MICs of PWE from fruits were 5 g/100mL for Echerichia coli and Bacillus pumilus, and 3 g/100mL for Staphylococcus aureus and Bacillus subtilis. MICs of PAE from fruits were 3 g/100mL for Echerichia coli, and 1g/100mL for Staphylococcus aureus, Bacillus pumilus and Bacillus subtilis.

Basic Research
Effect of Cooking Condition on Quality of Chicken Soup and Texture Analysis of Chicken Muscle
WANG Yi,HE Xiao-feng,YUE Xin-yu,FENG Xi,HUANG Wen*
2010, 31(9 ):  120-125.  doi:10.7506/spkx1002-6630-201009029
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Combinatorial analysis of sensory quality evaluation and nutrition compositions of chicken soup was conducted to investigate the effects of heating time, chicken types, addition amount and sequence of salt on quality of chicken soup. Results showed that moderate cooking for 100 min, 1:1 of native chicken and broiler, 2 g salt amount in 100 g chicken, and salt addition at the end of cooking could provide better quality of chicken soup and richer nutrition components. The parameters such as hardness, chewiness, cohesiveness and elasticity of chicken treated by high-pressure were investigated through texture analyzer. The correlation coefficients between 4 parameters and sensory quality evaluation were determined to be 0.995, 0.9918, 0.671 and 0.579, respectively. These results exhibited that tenderness of chicken could be determined using texture analyzer through the reflection of hardness and chewiness in the mode of TPA.

Bioengineering
Lactobacillus ferment F1 Fermentation of Yogurt with Cholesterol-degrading Activity
YANG Yao1,ZENG Xiao-qun1,PAN Dao-dong1,2,*
2010, 31(9):  126-130.  doi:10.7506/spkx1002-6630-201009030
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Cardiovascular disease is now becoming one of the most dangerous diseases. Currently, the development of functional foods to prevent cardiovascular diseases is the hot topic in food science. The probiotic Lactobacillia with cholesterol-degrading activity screened from Chinese traditional fermented foods can be applied to develop functional foods, which will be good for cardiovascular diseases. Lactobacillus ferment F1 was screened to reveal high cholesterol-degrading activity. The effects of inoculum amount, fermentation time and fermentation temperature were investigated to evaluate yogurt quality. The fermentation condition was optimized through response surface analysis (RSA) and the optimal fermentation condition was 4.0% inoculum amount and fermentation at 39 ℃ for 8 h. Under this optimal condition, the degradation rate of cholesterol reached up to 49.16%, and increased by 8.79% than before optimization.

Isolation, Purification and Structural Modification of Exopolysaccharide from Lactobacillus plantarum C21
LI Sheng-yu,ZENG Xian-peng,ZHAO Yu-juan,ZHANG Xue,ZHANG Jian,YANG Zhen-nai*
2010, 31(9):  131-134.  doi:10.7506/spkx1002-6630-201009031
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In order to investigate the structure and properties of exopolysaccharide produced by Lactobacillus plantarum C21, a neutral exopolysaccharide was isolated from culture supernatant and purified by ethanol precipitation, DEAE-cellulose ion exchange column chromatography and gel filtration chromatography on Sepharose CL-6B column. The structure of this exopolysaccharide was determined by ion chromatography and FTIR spectroscopy and this exopolysaccharide was designated as PCPc. Results indicated that the PCPc was composed of D-galactose and D-glucose in a molar ratio of 1:2. Sulfated and phosphorylated derivatives of PCPc were also prepared.

Screening, Identification and Breeding of Conjugated Linoleic Acid-producing Lactobacillus plantarum by Mutation
LIU Pei,ZHOU Qian,SHEN Sheng-rong,RUAN Hui,MA Liu-liu,HE Guo-qing*
2010, 31(9):  135-139.  doi:10.7506/spkx1002-6630-201009032
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A lactic acid bacterial strain, lp15, having the ability to synthesize conjugated linoleic acid (CLA) was isolated from pickle juice samples. The strain lp15 was identified as Lactobacillus plantarum based on full-length 16S rRNA sequence analysis and API system. This strain was treated by ultraviolet and DES to obtain several mutant strains, which exhibited 29.3%-52.2% enhancement for CLA production. The strain lp15-2-1 exhibited the highest CLA productivity, which was up to 30.13 μg/mL after 48 h culture in the MRS medium added with LA at 0.2 mg/mL level. According to gas chromatographic analysis,  cis9, trans11-CLA was the predominant compound in the fermentation product, with a relative content of up to 76.5%. trans10, cis12-CLA approximately accounted for 23.5% of the fermentation product.

Inhibition Effect of Extract from Auricularia auricular on Quorum Sensing and Biofilm Formation of Bacteria
LI Bin,DONG Ming-sheng*
2010, 31(9 ):  140-143.  doi:10.7506/spkx1002-6630-201009033
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Methanol-soluble compounds were extracted from Auricularia auricular to investigate the inhibition effect on quorum sensing through agar plate assays. The inhibition effect of extract from Auricularia auricular on biofilm formation of Escherichia coli 8099 was evaluated through ninety-six-well plate biofilm assay and disk reactor biofilm experiments. Approximately 72.16% inhibition rate on biofilm formation was observed in Auricularia auricular extract at the concentration of 0.3 g/mL.

Construction of VEGF Gene Plasmid and Transformation into Arabidopsis thaliana
LI Hong-zhi1,2,PANG Shi-feng3,LI Hai-yan1,XUE Ping1,LIU Xiu-ming1,LI Ying1,LI Wei1, XIAO Yan-shuang1,4,LI Xiao-kun1,4,*
2010, 31(9):  144-149.  doi:10.7506/spkx1002-6630-201009034
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In order to investigate exogenous protein expression in oil body system, the fragments of rape oleosin gene promoter (Ycprm) and rape oleosin gene (Ycoil) were obtained through PCR amplification using the designed primers and total DNA from Brassica napus L. VEGF gene was synthesized by overlap extension PCR. An oil body expression plasmid p1390Ycprm-Ycoil- VEGF was constructed by Ycprm, Ycoil and VEGF gene using the reconstruction vector, pCAMBIA1390. This recombinant plasmid was transformed into A. tumefaciens GV3101. A resistant plant, T1, was obtained in 1/2 MS medium containing hygromycin at the concentration of 20 mg/L by screening the seeds (T0) of transformed Arabidopsis plants. The results of PCR, SDS-PAGE and Western blotting showed that the fusion protein with Ycoil gene and VEGF gene were successfully expressed in Arabidopsis thaliana.

Screening and Identification of Antagonistic Bacteria against Post-harvest Diseases of Jujube Fruits
GENG Hai-feng1,ZHANG Li-zhen2,*,NIU Wei3
2010, 31(9):  150-155.  doi:10.7506/spkx1002-6630-201009035
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Eleven strains of antagonistic bacteria were isolated from soil samples and exhibited an excellent antagonistic effect on Alternaria alternate, Fusarium decemcellulare Brick and Monilia fructicola. Results showed strain B26 had the strongest inhibition effect on three selected fungal pathogens. The average radius of inhibition zone was 15.8 mm in plate inhibition test and inhibition rate against Alternaria alternate was 78.8%. Similarly, strain B26 also exhibited inhibition effect on Fusarium decemcellulare Brick and Monilia fructicola with average radius of 14.3 mm and 12.8 mm, and inhibition rate of 71.3 % and 63.8%, respectively. Strain B26 was primarily identified as Bacillus subtilis through the characterization of morphological features, cultural characteristic observation PDA, physiological and biochemical measurements and 16S rDNA sequence analysis of PCR products.

Optimization of Solid-state Fermentation Condition for Chymosin Production by Rhizopus
HAN Ling-ling1, PAN Dao-dong1,2,*
2010, 31(9):  156-160.  doi:10.7506/spkx1002-6630-201009036
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In this study, the solid-state fermentation conditions for producing chymosin with Rhizopus were optimized through single factor experiments and response surface methodology. The optimal fermentation conditions were media with solid-liquid ratio of 0.99:1 (m/V), bran-rice ratio of 0.96:1 (m/m), milk powder addition amount of 0.81% (m/m) and fermentation at 24 ℃ for 7 days. The activity of chymosin produced at this optimal condition reached up to 72.92 SU/mL.

Effect of Pepsin-based Whey Protein Hydrolysates on Proliferation of Lactobacillus acidophilus
BAI Feng-ling1,2,LI Xiao-dong1,LIAO Ling1,ZHANG Bo-lin1,*,JIN Su1,WANG Tao1,JIANG Xiang-ning1
2010, 31(9):  161-165.  doi:10.7506/spkx1002-6630-201009037
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The optimal hydrolysis condition to obtain whey protein hyrolysates was pH 2.2, temperature at 65 ℃, substrate concentration of 2 g/100mL, and ratio between enzyme and substrate of 7%. The degree of hydrolysis (DH) reached up to 12. 51% whey protein. Whey protein hydrolysates and the fragments purified by ultra filtration and gel filtration exhibited an excellent proliferation effect on Lactobacillus acidophilus B. The fragments with molecular mass ranged from 213.2 to 956.9 D could promote this probiotic strain to grow 10 times faster than the control. Therefore, the addition of pepsin-based whey protein hydrolysates in media may be an economic and helpful strategy to improve the proliferation of probiotics.

Effect of Mycelia Morphology of Rhizopus oryzae on Repeated Intermittent Fermentation of L-lactic Acid
ZHENG Zhi,DU Wei,JIANG Shao-tong*,WU Xue-feng,LI Xing-jiang,LUO Shui-zhong, ZHANG Ren-yuan
2010, 31(9):  166-170.  doi:10.7506/spkx1002-6630-201009038
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The effect of Rhizopus oryzae strain on fermentation intensity of L-lactic acid during repeated intermittent fermentation in a 3 L fermentor were investigated. Results demonstrated that the yields of L-lactic acid were 105.8 g/L and 105.0 g/L through in the first batch fermentation by Rhizopus oryzae strain in flocs-form and pellet-form, and glucose conversion rates were 88.12 % and 87.50%, respectively. The average yield of L-lactic acid fermentation through Rhizopus oryzae strain in pellet-form was more than 80.00 g/L during the first 6 repeated intermittent fermentations. The glucose conversion rate was higher than 87.33%, and the highest L-lactic acid productivity was 4.26 g/(L·h). However, the yield of L-lactic acid was decreased to 78.60 g/L in the 7th batch fermentation. The average yield of L-lactic acid fermentation through Rhizopus oryzae strain in flocs-form was more than 80.00 g/L during the first 4 repeated intermittent fermentations. But the yield of L-lactic acid was decreased to 78.30, 77.40 g/L and 70.20 g/L in the following 3 batches of fermentation. The highest productivity for L-lactic acid reached up to 4.07 g/(L·h).

Comparison of pET Vectors for the Expression of Single Chain Antibody for Aflatoxin B1
YANG Lian,LIU Zi-qin,LIU Rong,CHEN Hai-qin,CHEN Wei,ZHANG Hao*
2010, 31(9):  171-176.  doi:10.7506/spkx1002-6630-201009039
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Objective: Recombinant antibody expression in microorganism greatly facilitated the affinity and stability studies of recombinant antibodies, but previous studies had less reports about the selection of vectors. A suitable expression vector is important during the expression of the single chain antibody (scFv-H4) for aflatoxin B1. Methods: Four pET vectors such as pET20b, pET22b, pET28a and pET32a were employed in the functional expression of scFv-H4. Results: pET20b and pET22b vectors were able to express the functional antibody in periplasm. The vector of pET28a was not suitable for the expression of scFv-H4 due to lack of detectable scFv-H4 in total protein. Moreover, the detectable scFv-H4 was only expressed in inclusion body through pET32a expression system. Conclusion: pET22b was an excellent vector for the expression of scFv-H4, which might be a good reference for similar protein expression and be useful in the later study of scFv-H4 affinity and stability.

Diversity of Hexanol-degrading Strains in Soil
ZHANG Jin-hua,SHI Jun-ling*
2010, 31(9):  177-181.  doi:10.7506/spkx1002-6630-201009040
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Hexanol is an unfavorable flavor in food. Too much hexanol in food is harmful for human health. Screening and understanding diversity of hexanol-degrading microorganisms are helpful for biological degradation of hexanol and its potential application in food industry, which will provide basic information for further research on hexanol-degrading mechanisms. Soil around wastewater outfalls of hexanol-producing plants was used as the resources to screen hexanoldegrading microorganisms. After enrichment and isolation, 6 strains with degradation capability for hexanol were obtained. Based on morphological characteristics of colonies and spores, 6 strains were classified as fungi, which belonged to Fusarium Link, Geotrichum Link, Mucor Link and Aspergillus P. Micheliex Link, respectively. Geotrichum Link had 3 isolated strains, which exhibited higher hexanol-degrading capacity and wider suitability of pH. The strains in Geotrichum Link, S12 and S13 could result in the degradation of 3 g/L hexanol up to 60% under both neutral and acidic conditions. The rich diversity of hexanol-degrading strains in soil was reflected in species, ecology, degradation capacity, conditions and other aspects.

Molecular Identification of Medicinal Fungus Sanghuang based on rDNA ITS Sequence Analysis
XIE Li-yuan1,2,ZHANG Yong3,*,DENG Ke-jun3,PENG Wei-hong1,GAN Bing-cheng1,LI Hong-jun2
2010, 31(9):  182-186.  doi:10.7506/spkx1002-6630-201009041
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In this study, the ribosomal DNA internal transcribed spacer (rDNA ITS) region of six species of Sanghuang was cloned and sequenced, and the characteristics of ITS sequences were compared and analyzed. The ITS sequences exhibited homology through BLAST analysis of GenBank database and a phylogentic tree was constructed. Results demonstrated that phylogenetic relationship of Sh-03, 04, 05 and 06 was close to Phellinus linteus, and phylogenetic relationship of Sh-01 was close to Phellinus baumii; but Sh-02 had distant phylogenetic relationship with Phellinus baumii, Phellinus linteus and Phellinus igniarius. Therefore, the characteristics of rDNA ITS sequences can be used as an accurate, reliable and straightforward method to identify the original species of Sanghuang and explore genetic diversity.

Identification and Enzymological Characterization of Glutamate Carboxylase-producing Pediococcus
LI Yun,YANG Sheng-yuan*,CHEN Yu-na,LIU Xiang-liu,MAI Zhen-zhen,CHEN Yan
2010, 31(9):  187-191.  doi:10.7506/spkx1002-6630-201009042
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A glutamate decarboxylase (GAD)-producing lactic acid bacteria (LAB) strain HS2 was isolated from pickled vegetable. When the biotransformation was conducted in cells with strain HS2 for 1 h, the content of γ-aminobutyric acid in biotransformation solution of strain HS2 was (13.114 ± 0.133) g/L. Base on morphological, physiological and biochemical characteristics, 16S rDNA and phylogenic analysis, the strain HS2 was identified as Pediococcus pentosaceus. The optimal temperature and pH for GAD activity were 35 ℃ and 4.5. The GAD from strain HS2 was stable at 50 ℃ for 4 h and resistant to pH in the range of 4.0-6.5. In addition, calcium ions could result in a significant increase of GAD activity, which resulted in an enhancement of GAD activity by 37.21% and 23.02% at the concentrations of 5 mmol/L and 50 mmol/L Ca2+. Similarly, Mg2+ and Mn2+ also could increase GAD activity at the concentration of 50 mmol/L, whereas Co2+ could improve GAD activity at the concentration of 5 mmol/L.

Optimization of Nutritional Supplements for Fermentation Medium based on Sesame Cake for the Production of Antioxidant Substances by Aspergillus sojae
SHAO Yuan-long,DONG Ying*
2010, 31(9):  192-196.  doi:10.7506/spkx1002-6630-201009043
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Response surface methodology was used to optimize fermentation condition to improve antioxidant activity in solidstate sesame cake by Aspergillus sojae. The effects of maltose, glucose, sucrose, fructose, wheat bran, corn steep, yeast extract and ammonium sulfate on scavenging capability of sesame cake to DPPH free radicals were evaluated by using Plackett-Burman design. Results showed that wheat bran and glucose as well as ammonium sulfate were the major factors and had significant effect on antioxidant activity. Meanwhile, the central composite experimental design and response surface analysis were used to optimize the levels of major factors. The optimal condition was 1.87% glucose, 1.54% ammonium sulfate and 2.55% wheat bran, respectively. Under this optimal fermentation condition, the scavenging capability of sesame cake to DPPH free radicals was 80.26%.

Comparative Studies on Antioxidant Activities of Different Lactic Acid Bacterial Strains
WANG Xi1,LUO Xia2,XU Xiao-yan2,YU Meng-yao2,YU Chun-lian3,JIANG Nan2,ZENG Jin2,YANG Zhi-rong1,*
2010, 31(9):  197-201.  doi:10.7506/spkx1002-6630-201009044
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Objective: In order to provide theoretical evidences for developing novel natural antioxidants, antioxidant activities of different lactic acid bacterial strains were compared in this paper. Methods: The antioxidant capabilities and reducing activities of 35 lactic acid bacterial strains from intact cells, cell-free extracts and extracellular secretions were evaluated through scavenging capabilities of hydroxyl, superoxide anion and DPPH free radicals. Results: La 5 and La 29 displayed the excellent antioxidant activity among 35 lactic acid bacterial strains. Conclusion: Different fractions from lactic acid bacteria have different scavenging capabilities in vitro. Therefore, lactic acid bacteria from difference resources, concentrations and excretion places also exhibited different antioxidant activities.

Screening and Identification of Cholesterol Oxidase-producing Strains with High Activity
CAI Dan,ZHANG Na-na,LIU Jing-sheng*
2010, 31(9 ):  202-205.  doi:10.7506/spkx1002-6630-201009045
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Twenty-three strains using cholesterol as the sole carbon source were isolated from nine samples collected from different locations. One strain with high yield of extracellular cholesterol oxidase was screened and named as strain A3. The highest activity of cholesterol oxidase was 525 U/L. The strain A3 was identified as Brevibacterium sp. through analyzing its morphology, physiological and biochemical characteristics.

Optimal Condition for Selenium-rich Yeast Cultivation in Beerwort Media
LIU Jie1,CHEN Zhi2,LI Wei-qi1,XU Lin2,WU Gen-fu1,*
2010, 31(9):  206-210.  doi:10.7506/spkx1002-6630-201009046
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The optimal cultivation condition for yeast growth and selenium accumulation in beerwort media was studied. Results indicated that 2oBx beerwort was a suitable medium for the growth of Saccharomyces cerevisiae and the higher concentration would reduce growth rate by Crabtree effect. The addition of yeast extract in 2oBx beerwort could significantly increase yeast biomass; while the addition of (NH4)2SO4 or KH2PO4 did not. In addition, although glucose addition also could improve yeast biomass, its enhancement effect could be inhibited by simultaneous addition of (NH4)2SO4. Initial selenium concentration in media could remarkably improve yeast biomass and enhance selenium accumulation. At the initial concentration of 10 mg/L Na2SeO3, yeast biomass and accumulated selenium reached up to 2.83 g/L and 266.3 mg/kg, respectively.

Screening and Inhibitory Activity of Endophytic Fungi from Acorus calamus L.
ZHOU Xiao-kun1,CHEN Jun1,*,HAN Bang-xing1,2,HE Jia1,LIU Chang-feng1
2010, 31(9):  211-215.  doi:10.7506/spkx1002-6630-201009047
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In order to isolate and screen endophytic fungi with inhibitory activity from Acorus calamus L., active strains were screened through modified TTC micro-dilution method. MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) were detected using 18 food spoilage strains. Results indicated that 40.7% endophytes exhibited antimicrobial activity and 12.39% endophytes exhibited higher antimicrobial activity. In addition, strain S9 exhibited the broadspectrum antimicrobial activity to bacteria, yeast and mycelia fungi. Active endophytic strains from A. calamus L. are potential resources for food preservation.

Factors Affecting the Determination of Superoxide Dismutase Activity
ZHAO Jian1,LI Xiang2,LU Zheng1,WEN Jing1,*
2010, 31(9):  216-218.  doi:10.7506/spkx1002-6630-201009048
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Objective: To verify the factors for affecting the determination of superoxide disutase (SOD) activity in xanthine oxidase method and the evaluation error for antioxidant functions of healthy food. Methods: Effects of the addition of albumin, total protein, triglyceride, glucose, vitamin C and glutathione on SOD determination in xanthine oxidase method and on specific activity of SOD in mice treated with vitamin C through gastric perfusion. Results: In xanthine oxidase method, the specific activity of SOD still could be detected although SOD was inactivated. The addition of above six substances could disturb determination results of SOD activity. However, dialysis could eliminate the interference from small molecular substances in serum. Conclusion: Xanthine oxidase method for detecting SOD activity is a non-specific method. Protein, fat, vitamin C and glutathione in serum can affect SOD activity to result in a positive error. Dialysis is a simple and effective method to remove these interference substances.

Preliminary Identification and Aroma Component Analysis in an Aroma-producing Strain
LI Feng,MING Yan-hong,LI Yuan-yuan,PAN Yao,CHEN Qi
2010, 31(9):  219-223.  doi:10.7506/spkx1002-6630-201009049
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An aroma-producing strain was isolated and purified from soil samples collected from Dangshan Anhui province in China and prliminarily identified as Geotrichum based on morphological characteristivs. Hs-S-SPME and GC-MS results indicated that major aroma components were esters and alcohols. The esters exhibited the highest content, which were about 32 species and accounted for 73.84%. In addition, the alcohols were 8 species, which were accounted for 12.53%.

Nutrition & Hygiene
Screening and Hypocholesterolemic Effect of Lactobacillus fermentum
YAN Yu-ting1,PAN Dao-dong1,2,*
2010, 31(9):  224-228.  doi:10.7506/spkx1002-6630-201009050
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The strain SM-7 with hpocholesterolemic activity was screened from 10 lactic acid bacteria (LAB) strains isolated from koumiss in Xinjiang and its hpocholesterolemic effect in mice was investigated. The SM-7 was identified as Lactobacillus fermentum and could reduce 66.82% of cholesterol in the medium. The effect of strain SM-7 on serum TC, TG, HDL-C, LDLC, body weight, liver and kidney were investigated in ICR mice with hyperlipemia. Results showed serum TC, TG and LDL-C concentrations were exhibited a significant decrease (P < 0.01) while no obvious change was observed in serum HDL-C concentration (P > 0.05). These investigations suggested that Lactobacillus fermentum SM-7 strain had a significant effect on cholesterol-reducing function in mice with hyperlipemia.

Effect of Polysaccharides from Vitis viniferal L. on Immune Function in Mice
YU Dan1,ZHAO Jun2,LIU Tao1,SU De-qi1,MA Long1,*
2010, 31(9):  229-233.  doi:10.7506/spkx1002-6630-201009051
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Objectives: To study the effect of polysaccharides from Vitis viniferal L. (VTP) on immune function in mice. Methods: VTP was extracted using water and precipitated using 95% ethanol. The content of VTP was assayed with phenol-vitriolic colorimetry. Immunosuppressed mice were induced by cyclophosphamide and their indices of thymus and spleen, antibodysecreting cell function, serum hemolysin level and lymphocyte transformation capability were measured. Results: The content of polysaccharides in VTP crude extract was 20.68% with the RSD of 1.93%. Compared with the model group, VTP could increase spleen weight of mice, significantly promote lymphocyte transformation capability and antibody-secreting cell function, and improve serum hemolysin level. Conclusion: VTP could improve both humoral immune function and cellular immune function of immunosuppressed mice.

Extraction, Isolation and Protective Effect of Alkaloid from Seabuckthorn Seeds on Injured Cardiomyocytes in Rats
HU Chang-ying1,XU De-ping2
2010, 31(9):  234-237.  doi:10.7506/spkx1002-6630-201009052
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Objective: To investigate the protective effect of alkaloid from seabuckthorn seeds on injured cardiomyocytes in rats. Methods: EtOH extract from seabuckthorn seeds was purified by column chromatography and its structure was elucidated by MS and NMR spectroscopic analyses. A model of cardiac ischemic/reperfusion (I/R) in vitro was established using the primary cultured rat cardiomyocytes. The viability of cardiomyocytes was evaluated by MTT assay and the contents of lactate dehydrogenase (LDH) and creatine kinase (CK) were measured to verify the protective effect on injured rat cardiomyocytes by I/R. Results: The structure of water-soluble alkaloid was identified as 5,11-dihydroxyltryptamine, which could promote the survival rate of cardiomyocytes subjected to I/R injury and reduced the release of myocardial enzymes induced by I/R injury. Conclusion: The identified 5,11-dihydroxyltryptamine from seabuckthorn seeds exhibited an excellent protective effect on cultured neonatal rat cardiomyocytes injured by ischemia/reperfusion at the optimal concentration of 150 mg/L.

Antioxidative Effect of Whey Protein Hydrolysates in Serum, Heart and Kidney of D-galactose-induced Aging Rats
PENG Xin-yan1,2,KONG Bao-hua2,*,XIONG You-ling3
2010, 31(9):  238-242.  doi:10.7506/spkx1002-6630-201009053
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The antioxidative effect of whey protein isolate (WPI) hydrolysates on aging rats induced by D-galactose (D-gal) was investigated. The rats were divided into seven groups including the control group, D-gal model group, D-gal-induced rats treated with unhydrolyzed WPI, D-gal-induced rats treated with WPI hydrolysates at low, middle and high dosages, and D-gal-induced rats treated with ascorbic acid as the positive group. The experiment period was last for 45 days. The effect of WPI hydrolysates on antioxidative enzyme system including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and hydrogen peroxidase (CAT) in rats was evaluated, and the content of malondialdehyde (MDA) was determined. Results showed that WPI hydrolysates at three dosage levels significantly increased SOD and GSH-Px activities and simultaneously decreased MDA content in serum, heart and kidney tissues. The CAT activity in liver tissue of treated rats was also improved (P < 0.05). Moreover, a higher SOD activity was observed in rats treated with WPI hydrolysates at the dosage of 200 mg/kg· bw. Compared with the negative control, the SOD activity in serum of rats treated with WPI hydrolysates at the high dosage was increased by 29.2%. No significant difference in GSH-Px activity in kidney and CAT activity in liver between WPI hydrolysate treatment at the high dosage and the positive control of ascorbic acid was observed (P >0.05). In contrast, compared with the negative control, the MDA content in rats treated with WPI hydrolysates at the dosage of 100 mg/kg bw was decreased by 38.6% in heart. Therefore, WPI hydrolysates delayed the aging process of rats due to the increase of the activity in antioxdative enzyme system.

Selenitation of Lycium barbarum Polysaccharides and Inhibiting Effect on Human Cervical Carcinoma Cells Cervical Carcinoma Cell
LIANG Shu-xuan1,MA Er-hong1,XU Cheng-yan1,ZHAO Yan-yan2,SUN Han-wen1,*
2010, 31(9):  243-246.  doi:10.7506/spkx1002-6630-201009054
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Lycium barbarum polysaccharides were modified by sodium selenite in the presence of nitric acid as catalyst. The optimal reaction condition was the reaction at 70 ℃ for 10 h with the following dialysis for 24 h. The anticancer activity of selenited Lycium barbarum polysaccharides was evaluated in vitro. Results indicated that selenited Lycium barbarum polysaccharides could inhibit human cervical carcinoma cells, and exhibited a significant difference from Lycium barbarum polysaccharides.

Effect of Ultra-micronized Okara Dietary Fiber on Serum Cholesterol and Triglyceride Levels in BALB/c Mice
LE Bi-yun,LIU Cheng-mei*,LIU Wei,ZHANG Yu,WAN Jie
2010, 31(9 ):  247-250.  doi:10.7506/spkx1002-6630-201009055
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Dietary fiber was separated from okara, and then micronized through dry grinding method using ultra-micro pulverizer and wet granulating method using dynamic high pressure microfluidization, respectively. The samples were collected as D-ODF and W-ODF. Un-micronized dietary fiber (C-ODF) was the control diet. The changes of major physical and chemical properties before and after micronization were examined and effects of these samples on levels of serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and triglyceride (TG) were determined in BALB/c mice. Results indicated that particle size of W-ODF exhibited more significant declined than that of D-ODF. Meanwhile, swelling capacity, water holding capacity and soluble dietary fiber content in W-ODF were higher than those of D-ODF and C-ODF. The TC level exhibited a decrease in mice fed with D-ODF for 28 days through comparing with the TC level pre-treatments. However, the TC level in mice of both control groups and W-ODF group revealed an increase. In addition, serum HDL-C levels of all groups exhibited an increase; the ratio of HDLC/ TC in W-ODF group was increased by 21.2%, which was significantly higher than that of C-ODF (4.8%) and D-ODF (11.4%). TG level of control group was also increased, however, 13.5% reduction in D-ODF group and 29.2% decrease in W-ODF group were observed, compared with pre-feeding. Compared with the control group, TG levels in D-ODF group and W-ODF group were decreased by 17.9% (P < 0.05) and 41.0% (P < 0.05), respectively. W-ODF exhibited more prominent effect on TG level.

Antioxidant Effect of Rice Bran Peptides in Rats
FAN Jin-juan,LUO Xia,FU Yan-song,ZHANG You-zhu,LIU Guang-wen
2010, 31(9):  251-254.  doi:10.7506/spkx1002-6630-201009056
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In this study, biological functions of rice bran antioxidant peptides were investigated. Results indicated that rice bran antioxidant peptides exhibited an effective scavenging capability to free radicals and inhibit peroxide reactions of hemoglobin and hemolysis of red blood cells (RBC); moreover, rice bran antioxidant peptides also revealed an excellent inhibition effect on MDA generated from RBC, liver tissue and H2O2 oxidation system. Furthermore, rice bran antioxidant peptides also could suppress the generation of lipofasci from liver tissues induced by H2O2.

Polysaccharide Extract from Russula and Its Role of Lowering Blood Glucose and Lipid
CHEN Xu-jian1,ZHANG Yuan-qi2
2010, 31(9):  255-258.  doi:10.7506/spkx1002-6630-201009057
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Objective: To explore the purification of Russula polysaccharide and its role of lowering glucose and lipid. Methods: Crude polysaccharide was extracted from Russula fruit bodies through soaking extraction method in hot water and purified through ion-exchange chromatography and gel chromatography. The mice model with diabetes and hyperlipidemia was established through the injection of alloxan and the feeding of high-fat food. The model mice were administrated with Russula polysaccharide. Blood glucose and blood lipid in model mice with diabetes and hyperlipidemia were evaluated. Results: GLU, TC, TG and LDL-C exhibited a significant decrease (P <0.01) in mice with the administration of Russula polysaccharide in a dose-dependent manner. Conclusion: Russula polysaccharide has excellent functions in lowering blood glucose and lipid levels.

Effect of Polysaccharide from Moso Bamboo Leaves on Blood Lipid of Mice with Hyperlipemia
DING Hong-xiu1,2,GAO Yin-yu2,*,CHAO Hong-juan2,XIA Dong-hua2
2010, 31(9):  259-262.  doi:10.7506/spkx1002-6630-201009058
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In order to investigate the functions of polysaccharide from moso bamboo leaves (PMBL) for decreasing blood lipid and liver lipid and promoting the recovery of damaged liver, the mice model with hyperlipidemia was established through the feeding of high-fat food to evaluate the effect of PMBL on lipid metabolism of mice. Totally 50 mice were divided into 5 groups designated as hyperlipidemia model group, PMBL groups at low, middle and high dosages, and positive control group. Blood lipid, serum ALT, crude fat content in liver, liver index and morphological change of liver tissues were evaluated. Results indicated PMBL could result in a significant reduction of total cholesterol, triglyceride and low-density lipoprotein in serum; however, no significant effect on high-density lipoprotein was observed. In addition, PMBL could decrease crude fat content in liver, and improve the hepatic function of mice. In a word, PMBL exhibited anti-lipidemic activity and lipid-reducing effect in liver to enhance the repairing of damaged liver in mice with hyperlipidemia at the condition of optimal dosage.

Analysis and Evaluation of Nutritional Components in Different Locations of Banana Inflorescence
SHENG Zhan-wu1,MA Wei-hong1,GAO Jin-he1,LI Jing-yang1,HAN Li-na1,JIN Zhi-qiang1,2,*
2010, 31(9):  263-267.  doi:10.7506/spkx1002-6630-201009059
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In order to utilize the resource and medical value of banana inflorescence, nutritional compositions and functional components were analyzed in different locations of banana inflorescence (Musa AAA group cv baxijiao ) grown in Hainan. Results showed that the levels of different nutritional factors exhibited a significant difference (P<0.05) among different locations. Higher contents of protein, crude fat and ash, and lower content of water were determined in flowers and growth points. Flowers had the highest content of total dietary fiber, which was up to 5.74 g/100 g. Meanwhile, larger amount of minerals were also determined in three locations, and the highest composition of these major elements were potassium, which was ranged from 42.07 to 57.13 mg/kg. In addition, totally 18 essential and non-essential amino acids in these tissues were detected and the content of glycine, leucine and alanine were rich. Among these essential amino acids, lysine revealed the lowest chemical score and amino acid score. In three tissues, growth point contained the highest levels of unsaturated fatty acids (70.2%). The contents of vitamin E, total saponin and flavonoids were also investigated and rich in banana flowers. These investigations provided a fundamental nutritional data of banana inflorescence for food science.

Purification and Hypolipidemic Effect of Polysaccharides from Fruit Body of Pholiota adipose
LI De-hai1,WANG Zhi-qiang1,SUN Chang-yan2,WANG Ping1,*
2010, 31(9):  268-271.  doi:10.7506/spkx1002-6630-201009060
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Objective: To explore the purification method and hypolipidemic effect of polysaccharides from fruit body of Pholiota adipose polysaccharides. Methods: The crude polysaccharides were purified after removing protein by neutral protease and Sevag method. Experimental mice were divided into five groups including NS control group, the model group with high fat diet, the treatment groups fed with purified polysaccharides at the low-dosage of 100 mg/(kg bw·d), the medium-dosage of 200 mg/(kg bw·d) and the high-dosage of 400 mg/(kg bw·d). Due to the high fat diet, the model of hyperlipidemia was successfully established. After five weeks, the contents of serum TC, TG, high-density cholesterol (HDL-C), low-density cholesterol (LDL-C) were determined. Results: Purified polysaccharides from Pholiota adipose at three dosages exhibited the significant decrease in TC (high-dosage group and low-dosage group P<0.05), TG (medium-dosage group P<0.05, high-dosage group and low-dosage group P<0.01), LDL-C (medium-dosage group and high-dosage group P<0.05, low-dosage group P<0.01), the significant improvement in HDL-C (high-dosage group and low-dosage group P<0.05,medium-dosgage group P<0.01) and arteriosclerosis factor (AI) (high-dosage group P<0.05). Conclusion: Polysaccharides from Pholiota adipose play an important role in the reduction of blood lipid and prevention of arteriosclerosis in mice.

in vitro Hypotensive Effect of Hydrolyzed Soybean Protein
SUN Yang,SUN Chun-yu,CHEN Guang*
2010, 31(9):  272-275.  doi:10.7506/spkx1002-6630-201009061
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Soybean protein hydrolysates were prepared by enzymatic hydrolysis with alcalase. Inhibitory activities of enzymatic hydrolysates and the purification fractions to angiotensin I converting enzyme (ACE) were determined for evaluating their hypotensive effects. Results showed that both enzymatic hydrolysates and purified fractions with smaller molecular weights exhibited higher hypotensive activity. However, exonuclease treatment could result in the improvement of flavor and reduction of hypotensive activity for hydrolysates.

Protective Effect of Atractylodes rhizom Polysaccharides on Adenine-induced Renal Failure in Rats
FENG Xing1,QIU Xi-min1,HUANG Ya-lin1,LIU Xiong-zhi1,LI Sai1,ZHENG Ni2
2010, 31(9):  276-278.  doi:10.7506/spkx1002-6630-201009062
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Objective: To investigate the preventive effect of Atractylodes rhizome polysaccharides (AP) on chronic renal failure (CRF) rats-induced by adenine. Methods: CRF model was induced by adenine. The rats were randomized into five groups, which were designated as control group, model group, groups administered with AP at the high (APH) and low dosages (APL), and dexamethasone group. After the administration, the rats were fed in metabolism cage. The urine was collected during 12 h period without food or water. The total volume of urine, blood urine nitrogen (BUN), urine creatinine (CR), and 12-hour urine protein (12 h U-TP) were determined. Meanwhile, renal index was also evaluated. Results: Compared with the model group, BUN levels of CPL and CPH groups exhibited a significant decrease (P<0.01 or P<0.05). Similarly, a significant declined coefficient was also observed (P<0.01, P<0.05). Conclusion: AP revealed a promising preventive effect on renal failure in rats.

Safety Evaluation of Roxarsone in Livestock Products
ZHOU Yan-ming1,ZHU Jun1,YU Wei-jun1,SHI Jiao2
2010, 31(9):  279-283.  doi:10.7506/spkx1002-6630-201009063
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In order to standardize the application of roxarsone, improve the food safety, and provide theoretical references for risk management of food safety, a combinatorial strategy for risk evaluation and toxicological experiments in animals were used to identify and test roxarsone in livestock products. A risk management model was established in livestock products through risk evaluation software, @Risk5.5. Therefore, the probability of exceeding standard for roxarsone in large supermarkets and small markets was induced.

Evaluation of Nutritional Components in Gracilaria lemaneiformis
ZHOU Shi-miao,HE Qing, MA Xiao-yu
2010, 31(9 ):  284-287.  doi:10.7506/spkx1002-6630-201009064
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Nutritional components including amino acids and minerals in Gracilaria lemaneiformis collected from Wenzhou Eastern Sea area were analyzed and compared with other seaweeds such as Laminaria japonica, Porphyra haitanensis, Hizikia fusiformis and Undaria pinnatifida for evaluating their nutritional values. Results indicated that polysaccharides and crude fibers in Gracilaria lemaneiformis reached up to 59.4%. The total protein in Gracilaria lemaneiformis was 18.9%, which was higher than that of other seaweeds. Amino acid compositions of protein in Gracilaria lemaneiformis remained a balance status with the ratios of 36.6% for EAA/TAA and 0.58 for EAA/NEAA. The content of amino acids for flavor development was 51.5% of total amino acid. In addition, glutamic acid, aspartic acid, alanine, leucine, proline, serine and methionine exhibited higher contents and crude fat exhibited a lower level in Gracilaria lemaneiformis. Minerals and vitamins were rich in Gracilaria lemaneiformis, especially for Mg, Fe, Ca, Na and Zn. Moreover, Fe and Zn were higher than other seaweeds. Therefore, Gracilaria lemaneiformis might be the safe and healthy seaweed containing higher dietary fibers and proteins, lower fat and richer minerals.

Effect of Apple Polyphenol on Lipid Metabolism in Mice
WANG Zhen-yu1,2,ZHOU Li-ping1,LIU Yu1
2010, 31(9):  288-291.  doi:10.7506/spkx1002-6630-201009065
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Objective: To study the effect of apple polyphenol on lipid metabolism in mice. Methods: Totally 50 mice were randomly divided into 5 groups. Four groups were fed with high fat diet except for the normal control group. The normal control and obesity control groups were administrated with normal saline, and other three groups were administered with apple polyphenol at the dosages of 3.8, 7.6 mg/(kg bw·d) and 11.4 mg/(kg bw·d), respectively. Four weeks later, the mice were sacrificed to assay body weights, contents of serum total triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) malondialdehyde (MDA), activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), hepatic lipase (HL) and lipoprotein lipase (LPL). Results: Apple polyphenol could obviously reduce the body weights of mice, the contents of TG, TC, LDL-C and MDA, and atherosclerosis index (AI). In contrast, it could also improve HDL-C and the activities of SOD, GSH-PX, HL and LPL in serum. Conclusion: Apple polyphenol has the function in reducing blood lipid through adjusting lipid metabolism of mice to prevent atherosclerosis diseases.

Reviews
MAPK Response under Low-temperature Stress and Bioinformatic Prediction of LeMAPK Functions
DING Yang1,ZHAO Rui-rui1,SHEN Lin1,2,SHENG Ji-ping1,*
2010, 31(9 ):  292-296.  doi:10.7506/spkx1002-6630-201009066
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Mitogen-activated protein kinase (MAPK) cascade is an important pathway of signal transduction in plants to response the changes from external environment. MAPK cascade is involved in the process of low-temperature signal transduction and plays a dominant role in the amplification and transmission of signals. Currently, different MAPKs are discovered to be involved in low-temperature stress in plants. Research progress of MAPK was discussed in this article. Bioinformatic methods were also applied to predict relative functions of LeMAPKs in tomato. Therefore, this article provided the theoretical basis for further investigation on MAPK cascade mechanisms of signal transduction at low temperature.

Disease-resistant Mechanism of Post-harvest Fruits and Vegetables Induced by Antagonists
LUO Yang1,MING Jian1,2,ZENG Kai-fang1,2,*
2010, 31(9):  297-300.  doi:10.7506/spkx1002-6630-201009067
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Disease-resistant mechanism of post-harvest fruits and vegetables induced by antagonists has been reviewed. The antagonists improved resistance to disease in fruits and vegetables by improving the content of phyto alexi and the activities of defense enzymes such as chintinase (CHI), β-1,3-glucanase, phenylalanine ammonia-lyase (PAL), peroxidase (POD) and polyphenol oxidase (PPO). The antagonists also regulated the active oxygen metabolism, and strengthened the resistance of organization structure in fruits and vegetables. These studies on disease-resistant mechanism induced by the antagonists will provide references for the application of biological technology for disease control in post-harvest fruits and vegetables.

Application of SPR Biosensor in the Detection of Food Microorganisms:A Review
LIU Xia,LI Zong-jun*
2010, 31(9):  301-305.  doi:10.7506/spkx1002-6630-201009068
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Surface plasma resonance (SPR) is one of modern analytical techniques and can be used for monitoring inter-molecular interaction in real time. In addition, it can also be applied to detect biochemical parameters in an accurate, fast and convenient manner. Moreover, the detection of food microorganisms using SPR has been attracted extensive attentions in recent years. Current progresses in the detection of food microorganisms through SPR technique has been reviewed in this paper.

Advances in Identification of Protein Adulteration in Milk and Dairy Products
YANG Guang1,2,WANG Jia-qi1,*,BU Deng-pan1,Khas-Erdene1,LIU Qing-sheng1,SUN Peng1,LIU Kai-lang1,LUO Qiu-jiang2
2010, 31(9):  306-312.  doi:10.7506/spkx1002-6630-201009069
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Two methods with one principle for identifying protein adulteration in milk and dairy products have been summarized in this paper. Two methods were focused on specific and non-specific identification of protein adulteration in milk and dairy products. The main principle for establishing these detection methods was concentrated on the difference among specific proteins in adulterated milk and dairy products.

Research Progress in the Degradation of Glucosinolates
LI Chen,XUE Feng,MIAO Wen-hua,PAN Si-yi*
2010, 31(9):  313-317.  doi:10.7506/spkx1002-6630-201009070
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Biosynthesis, degradation pathways, degradation product analysis, degradation product functions of glucosinolates play important roles in the secondary metabolites in Cruciferae plants, which has been reviewed in this paper. The biosynthesis of glucosinolates was completed using amino acids as the substrates through three steps. The degradation pathways of glucosinolates were classified as enzymatic degradation, thermal degradation and chemical degradation. Chemical and chromatographic analyses were the major strategies for the analysis of glucosinolate degradation products. The degradation products of glucosinolates exhibited a positive role in anti-cancer as well as a negative role in anti-nutrient.

Research Progress in the Detection of Honey Adulteration
YUAN Yu-wei,ZHANG Zhi-heng,YE Xue-zhu,YANG Gui-ling,SUN Cai-xia,YU Guo-guang
2010, 31(9):  318-322.  doi:10.7506/spkx1002-6630-201009071
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The adulteration of honey is generally concerned by consumers and management departments of safety and quality. The adulteration of honey also affects the export of honey trade. In this paper, some basic characteristics and detection methods of honey adulteration has been reviewed. Stable carbon isotopic ratio technology, near-infrared spectroscopy, chromatogram analysis, enzymatic activity detection, microscopic analysis, differential scanning calorimetry and optical rotation detection were discussed based on their specialties and application ranges. Combinatorial detection methods for honey adulteration were proposed to identify the mixture of honey and set up a traceability system or fingerprint data for honey products, which may be important to ensure safety and quality of honey.

Healthcare Functions and Applications in Food Industry of Chlorella
KONG Wei-bao1,2,LI Long-nan1,ZHANG Ji1,XIA Chun-gu2,*
2010, 31(9):  323-328.  doi:10.7506/spkx1002-6630-201009072
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Chlorella is a kind of single cell alga containing plentiful proteins and polysaccharides, vitamins and minerals and low fat. Therefore, Chlorella has many healthcare functions and can be used in food industry as a functional food and nutritionenhancing agent. The research progress in exploitation and utilization, especially for nutritional value, healthcare functions and applications of Chlorella in food industry has been reviewed in this paper.

Fermentation Microorganisms and Their Healthcare Function in Black Tea
WEN Jie-yu,LI Zong-jun*,WANG Yuan-liang,XU Ai-qing
2010, 31(9):  329-332.  doi:10.7506/spkx1002-6630-201009073
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Black tea is one of traditional and unique tea products made in China. Microbes play an important role in quality and flavor formation in black tea. In this paper, current studies on types and safety of pile-fermentation microbes existing in black tea have been reviewed. Meanwhile, applications of DGGE technology to investigate on microbial diversity in black tea and function for weight loss have also discussed.

Research Progress in Biotransformation of Soybean Isoflavone Glycosides by β - Glucosidase and Probiotics
HAN Ting1,CHENG Gang2,LIU Ying1,HUANG Wen1,*
2010, 31(9 ):  333-337.  doi:10.7506/spkx1002-6630-201009074
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The isoflavone glycosides in soybeans and their prepared products are difficult to digest and absorb in human body. In current paper, research progress in biotransformation of soybean isoflavone glycosides to improve bioavailability through β-glucosidase at home and aboard has been reviewed. The transformation of isoflavone glucosides by exogenous β-glucosidase and β-glucosidase-producing probiotics has been discussed in detail.

Research Progress on Steviosides
SUN Chuan-fan1,LI Jin-wei2
2010, 31(9 ):  338-340. 
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Steviosides is a low heat energy sweetener. The international research progress on the foundation, extraction, isolation, structure, security and detect method of steviosides are reviewed in this paper. The future research trends of stevioside are proposed.