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Table of Content

15 May 2016, Volume 37 Issue 9
Basic Research
Effect and Mechanism of Flaxseed Gum on Thermal Gelling Properties of Porcine Myofibrillar Protein at Different Heating Temperatures
PAN Lihua, FENG Meiqin, SUN Jian, XU Xinglian, ZHOU Guanghong
2016, 37(9):  1-6.  doi:10.7506/spkx1002-6630-201609001
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The objective of the study was to explore the effect and mechanism of action of heating temperature and addition
of flaxseed gum (FG) on water-holding capacity (WHC), gel strength, rheological properties, secondary structure and
3-dimensional network structure of heat-induced gels of pork myofibrillar protein (MP). The results revealed that increasing
temperature could significantly decrease gel WHC (P < 0.05), and increase gel strength (P < 0.05). The addition of FG
significantly enhanced WHC and decreased gel strength at temperature higher than 50 ℃ (P < 0.05). Raman spectroscopic
analysis revealed that increasing the temperature from 30 to 80 ℃ induced partial transformation of α-helices into β-sheets.
At the same heating temperature, the addition of FG led to the transformation of α-helices into β-sheets, thus affecting the
formation of gels. The rheological tests showed that storage modulus (G’) values during MP gelation were declined with
addition of FG (P < 0.05) when temperature was higher than 50 ℃. Gel holes of MP appeared at 50 ℃, and MP-FG formed
a fine dense network at both 70 and 80 ℃ as shown by scanning electron microscopy images.

Combined Effect of Pulse Electric Field and Ultrasound on Functional Properties of Black Soybean Globin
BI Shuang, MA Wenjun, LI Yang, QI Baokun, WANG Zhongjiang, JIANG Lianzhou
2016, 37(9):  7-12.  doi:10.7506/spkx1002-6630-201609002
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The effect of combined pulsed electric field (15 kV/cm) and low-frequency ultrasound (150, 300 or 450 W)
treatments for different time periods on functional properties of black soybean globin was addressed in this study. Functional
properties of black soybean globin varied among different treatments. The highest water-holding capacity (75.69%) and
gel strength (45.126 g) were obtained when black soybean globin was treated with pulsed electric field at 15 kV/cm in
combination with ultrasound irradiation at 300 W for 36 min. Moreover, its solubility also increased after the combined
treatment, and its elastic modulus was the highest as indicated by rheological test. Frequency sweep rheological experiments
revealed that a solid-like gel network was formed from black soybean globin under the above treatment conditions. The
microstructure of the gel was more regular under scanning electron microscopy (SEM).

Relationship between Dielectric Properties and Physicochemical Properties of Apples during Late Developmental Period
KONG Fanrong, GUO Wenchuan
2016, 37(9):  13-17.  doi:10.7506/spkx1002-6630-201609003
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To understand the changing patterns of dielectric properties, physiological properties and internal qualities
during the late developmental period of apples and to illustrate the relationship between them, open-ended coaxial-line
probe technology was used to measure the dielectric constant ε’ and dielectric loss factor ε” of apples over the frequency
range of 20?4 500 MHz during the last three months of fruit development, along with the physiological parameters (the
amount of released ethylene and respiration intensity) and internal qualities (soluble solids content (SSC), firmness, pH and
moisture content). The results showed that ε’ decreased with increasing frequency, and ε” had minimum values at around
2 000 MHz. During fruit development, the dielectric constant ε’, dielectric loss factor ε” and firmness decreased, while SSC
and pH increased with maturity. The peak of released ethylene was found between two respiration peaks. There were good
linear relationships among dielectric constant ε’, dielectric loss factor ε”, SSC, firmness and pH in some frequency ranges.
This study indicated that the dielectric properties were a comprehensive reflection of physiological properties and internal
qualities. The maturity of apples could be judged by dielectric constant ε’ and dielectric loss factor ε”. It is feasible to assess
internal qualities of apples using a permittivity value at a given frequency.

Correlation Analysis between Heat Shock Protein 27 Expression and Eating Quality during Postmortem Aging of Yak Meat
LI Jie, LUO Tianlin, SHI Xixiong, HAN Ling, YU Qunli, MA Junyi
2016, 37(9):  18-22.  doi:10.7506/spkx1002-6630-201609004
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The objective of this study was to evaluate the relationship between the expression of heat shock protein 27 (Hsp27)
and eating quality of yak meat during postmortem aging. Loins (M. longissimus dorsi) from female Datong yak in Qinghai
were analyzed for changes in chromaticity, pH, shear force, cooking loss and Hsp27 concentration during postmortem
aging, and the relationship between Hsp27 and eating quality was determined. The results showed that Hsp27 concentration
generally tended to decrease during postmortem aging with a significant reduction observed during the first 48 h postmortem
(P < 0.05), followed by an increase from 72 to 120 h at first and then a significant decrease until 168 h at last (P < 0.05).
Statistical analysis indicated that Hsp27 level had a significantly negative correlation with b* value (P < 0.01), while it was
significantly positively correlated with a* value (P < 0.05) and pH (P < 0.01), respectively. In a word, these results suggested
that Hsp27 and yak meat eating quality are highly correlated.

Effect of Freeze-Thaw Cycles on the Quality of Broiler Breast and Thigh Muscles as Evaluated by Low-Field Nuclear Magnetic Resonance
ZHU Xueshen, HUANG Xuefang, LU Xiaoxun, WANG Yan, ZHAO Kaibin, XU Ming, WANG Renlei
2016, 37(9):  23-28.  doi:10.7506/spkx1002-6630-201609005
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In the present study, the effect of freeze-thaw cycles on the quality of broiler breast and thigh muscles was
explored by low-field nuclear magnetic resonance (LF-NMR). Results showed that thaw exudate loss of chicken breast and
thigh muscles significantly declined with increasing number of freeze-thaw cycles (P < 0.05), whereas no significant change
in pH was observed (P > 0.05). The thiobabituric acid reactive substance (TBARS) value of chicken breast and thigh muscles
rose significantly, and total protein solubility and myofibrillar fragmentation index (MFI) showed an increasing trend
initially. However, total water content gradually fell. At the same time, the proportion of free water as indicated by LF-NMR
T2 relaxation times significantly dropped. These above results suggested that freeze-thaw cycles resulted in a reduced
proportion of free water and consequently enhanced loss of thaw exudate in chicken muscles. pH maintenance during freezethaw
cycles confirmed that ice crystal formation caused damage to the microstructure of muscles, especially having a certain
influence on the solubility of myofibrillar protein.

Selection of Quality Indicators and Factor Analysis for Fruit Quality Evaluation of Ziziphus jujuba var. spinosa Germplasms
SUN Yaqiang, WU Cuiyun, WANG De, WANG Zhiqiang
2016, 37(9):  29-34.  doi:10.7506/spkx1002-6630-201609006
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In order to establish suitable methods to evaluate jujube quality and consequently guide the development and
utilization of wild jujube germplasms and the selection of excellent germplasms, evaluation and classification of 16 fruit
quality attributes such as single fruit weight, pericarp color, soluble sugar, titratable acid, vitamin C, fruit shape index, and
single stone weight were carried out on 50 germplasms of Ziziphus jujuba var. spinosa by factor analysis and cluster analysis
using SPSS software. The results showed that factor analysis extracted 6 main factors including single fruit weight, single
stone weight, appearance and nutrients, with a cumulative variance contribution rate of 83.173%. Principal component
analysis and cluster analysis were carried out using the loadings of the first 6 principal components. Pericarp color, single
fruit weight, titratable acid (or vitamin C), single stone weight, fruit shape index (or starch content), and soluble sugar
content were selected for cluster analysis of Ziziphus jujuba var. spinosa germplasms. When the squared Euclidean
distance was 14.0, the 50 germplasms could be classified into 4 categories. The first category had better fruit color
with higher acidity, the second one had larger fruits with higher proportion of edible part, and the third one contained
higher sugar contents.

Development of an Efficient Method for Total Protein Extraction from Yeast-Like Conidia of Tremella fuciformis
LIU Yang, ZHU Hanyu, XU Danyun, ZHANG Lijiao, MA Aimin
2016, 37(9):  35-39.  doi:10.7506/spkx1002-6630-201609007
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In order to compare extraction efficiencies of total protein from the yeast-like conidia of Tremella fuciformis by
Tris-saturated phenol method, trichloroacetic acid (TCA)-acetone precipitation method and their combination, the cells were
disrupted by ultrasound and high-pressure homogenization, the efficiency of cell disruption was observed by microscope,
protein content was determined by the Bradford method, and SDS-PAGE gel electrophoresis analysis was performed. The
results showed that the efficiency of cell disruption by high pressure homogenization was better than that by ultrasound. The
protein contents obtained by three extraction methods were 2.33, 1.26 and 1.02 mg/mL, respectively. The brightness and
resolution of electrophoresis bands with traditional coomassie brilliant blue staining by Tris-saturated phenol method were
better than those obtained by two other methods. Hence Tris-saturated phenol method can be considered as a feasible method
for protein extraction from the yeast-like conidia of T. fuciformis.

Effect of Steam Explosion on Total Isoflavone Content and Antioxidant Capacity of Puerariae thomsonii Radix
ZHANG Qi, YI Junpeng, LI Xin, WANG Xinsheng, LI Bing, ZHU Wenxue
2016, 37(9):  40-44.  doi:10.7506/spkx1002-6630-201609008
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Steam explosion pretreatment was employed on Puerariae thomsonii Radix at a steam pressure of 1.0 and
2.0 MPa for 30, 40, 60 and 80 s, respectively. In order to explore the effect of steam explosion pretreatment on the total
isoflavone content and antioxidant capacity of Puerariae thomsonii Radix, the content of total isoflavones was determined
using UV spectrophotometry. The 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was used to evaluate
free radical scavenging capacity. The results indicated that the extraction efficiency of total isoflavones, the yield of
methanol extract and antioxidant capacity significantly increased after steam explosion. Under optimal conditions, the
yield of total isoflavones (calculated as puerarin) was 5.43 mg/g, which was 2.32 times as much as that of the untreated
sample; the yield of methanol extract was 16.92%, and the 50% inhibitory concentration (IC50) for DPPH radical scavenging
activity decreased from 30.65 g/L to 10.10 g/L, suggesting that the antioxidant capacity was improved. It can be concluded
that a proper and reasonable steam explosion pretreatment can be applied to extract the active compounds and enhance the
antioxidant capacity of Puerariae thomsonii Radix.

Effect of Oxygen on Degradation of Chitosan with Swirling Cavitation
ZHANG Weiwei, REN Xiane, YANG Feng, HUANG Yongchun, HE Ren
2016, 37(9):  45-49.  doi:10.7506/spkx1002-6630-201609009
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In this research, the effect of oxygen on the degradation of chitosan by swirling cavitation under different
conditions of initial concentration of chitosan solution, pH, temperature, inlet pressure and cavitation time was studied.
The results showed that low initial concentration of chitosan solution resulted in better degradation efficiency of swirling
cavitation. When the following conditions were used: solution pH, 4.4; temperature, 70 ℃; inlet pressure, 0.4 MPa; and
cavitation time 3 h, chitosan solution showed the largest decline in intrinsic viscosity. Under each of the tested conditions,
continuous feeding of oxygen significantly augmented the decrease in intrinsic viscosity, which could result in the maximum
improvement of 35.36%. The effect of oxygen on the degradation of high chitosan concentration was more significant. pH
impact on the degradation of chitosan was weakened, and the reaction rate was greatly accelerated in the early stage of the
reaction as a result of increased oxygen supply. The major chain structure and functional groups of chitosan after degradation
were not changed.

Effect of Addition of Freeze-Dried Fig Fruit Powder on Quality of Wheat Flour
CUI Yong, DONG Jian, YANG Mingming, ZHAO Wanchun, LI Jianfang, GAO Xiang
2016, 37(9):  50-55.  doi:10.7506/spkx1002-6630-201609010
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The aim of this study was to investigate the influence of incorporating different levels (0%, 1%, 2%, 3%, 4%, and
5%) of freeze-dried fig fruit powder (FDP) on physicochemical properties of flours from 3 different wheat cultivars (Yumai 34,
Xinong 364 and Xinong 538) and the microstructure of dough from the wheat cultivar Xinong 364. The pasting and
farinograph properties of the blends were measured by Rapid Visco Analyzer and farinograph, respectively. As the FDP
level added in the blends increased, the sedimentation value, falling number, peak viscosity, trough viscosity, final viscosity,
breakdown and setback viscosity were significantly decreased. Moreover, increasing the level of FDP added in the blends
resulted in a decrease in water absorption, development time, stability time and farinograph quality number and an increase
in softness values. Scanning electron microscopy images also showed that FDP weakened the gluten-starch network of
dough, and higher degree of disruption of protein matrix was observed in dough with 3% FDP than 1% FDP. Therefore, the
addition of FDP can lead to changes in pasting properties, farinograph properties and microstructure of gluten.

Effect of Food Thickener on Gelation Properties of Squilla Myofibrillar Protein Induced by Phosphorylation
WANG Shimeng, ZHANG Kunsheng, REN Yunxia
2016, 37(9):  56-60.  doi:10.7506/spkx1002-6630-201609011
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Konjac glucomannan, carrageenan and xanthan gum were individually mixed into a mixture of sodium
tripolyphosphate and squilla myofibrillar protein (STP-MP) to investigate their effects on heat-induced protein gelation
properties as a function of STP concentration and heating temperature. The results showed that the gel strength and waterholding
capacity of heat-induced MP gels with the addition of each of the above three food thickeners increased with
increasing concentration of STP. Gel strength and water-holding capacity were increased by the addition of carrageenan and
xanthan gum in a concentration-dependent manner, and the highest water-holding capacity was observed by the addition
of 0.1% konjac glucomannan. Gel strength and water-holding capacity of MP gels induced by elevated temperature were
significantly affected by the addition of konjac glucomannan and carrageenan (P < 0.05) but not xanthan gum (P > 0.05).

Retrogradation Properties of Restructured Brown Rice
SHEN Wangyang, YAN Mengting, SUN Wei, CHEN Xuan, GAO Hong, ZHAO Yongwu, ZHOU Jian
2016, 37(9):  61-65.  doi:10.7506/spkx1002-6630-201609012
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The Avrami equation (describing the transformation kinetics in crystallization and solid state phase transition)
and the hardness of restructured brown rice were investigated by DSC and texture analyzer in the present study. Its
retrogradation properties were also explored. The results showed that the exponent n in the Avrami equation was less than
1. The crystallization was based on one-step nucleation. The amylose content significantly affected the Avrami parameter n,
while there was no significant difference between maximum retrogradation degree of amylopectin and amylose content. At
the same time, significantly negative correlation was observed between the parameter n and the crystal growth rate k. The
maximum degree of retrogradation and the crystal growth rate k were significantly negatively correlated with each other. The
hardness of cooked restructured brown rice showed its retrogradation degree.

Effect of Steaming Process on Taste Quality and Antioxidant Properties of Sweetpotato
WU Lingyan, SHEN Yanfei, ZHAO Xiaofei, YANG Huqing, LU Guoquan
2016, 37(9):  66-70.  doi:10.7506/spkx1002-6630-201609013
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This study probed into the effect of steaming process on taste quality and antioxidant properties of sweetpotato.
Sweetpotato tubers from two cultivars, “Xinxiang” and “Yuzi”, were steamed at 100, 110 and 121 ℃ for 15, 25 and 35 min,
respectively. Sensory quality, texture, and the contents of ascorbic acid, β-carotene, anthocyanin, total phenols,and total
flavonoids and antioxidant capacity were evaluated on the steamed samples. The results showed that the sensory quality of
sweetpotato steamed at 100 ℃ for 35 min, 110 ℃ for 25 min and 121 ℃ for 15 min was significantly (P < 0.05) better than
that of other treatments. Especially, steaming at 121 ℃ for 15 min decreased the loss of ascorbic acid, β-carotene and total
phenols, therefore maintaining higher antioxidant capacity. In conclusion, high-temperature short-time steaming is good for
improving taste quality and maintaining higher antioxidant capacity of sweetpotato.

Cholesterol-Lowering Effect of Persimmon Tannin in Vitro
ZHU Wei, ZOU Bo, GE Zhenzhen, ZHANG Ying, LI Chunmei
2016, 37(9):  71-76.  doi:10.7506/spkx1002-6630-201609014
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This study investigated the inhibitory effect of persimmon tannin on pancreatic lipase and pancreatic cholesterol
esterase activities. The binding capacity of persimmon tannin to cholesterol and bile acids was also determined by
spectrophotometry and gas chromatography. The results indicated that persimmon tannin significantly inhibited the activity
of pancreatic lipase with an IC50 value of (0.445 ± 0.021) mg/mL in an un-competitive manner, and the inhibitory constant
(Ki) was 0.406 mg/mL. Meanwhile, it also showed a strong inhibitory effect on pancreatic cholesterol esterase in an
un-competitive manner with an IC50 value of (0.442 ± 0.017) mg/mL and a Ki value of 0.488 mg/mL. At the concentration
of 10 mg/mL, the binding rates of persimmon tannin to cholic acid (CA) and deoxycholic acid (DCA) were 58% and 94%,
respectively. Persimmon tannin also could inhibit cholesterol micellization effectively, and the percentage inhibition was
found to be 67% when the concentration was 0.20 mg/mL. In addition, the cholesterol binding ability of persimmon tannin
was stronger at pH 7.0 than pH 2.0. These results suggested that persimmon tannin might decrease lipid absorption through
inhibiting the activities of pancreatic lipase and pancreatic cholesterol esterase, and binding cholesterol and bile acids. This
may explain the strong cholesterol-lowering effect of persimmon tannin in vivo.

Fruit Quality Evaluation of Superior Clones of Zizyphus jujuba cv. Huizao Based on Factor Analysis
FENG Huili, WU Zhengbao, SHI Yanjiang, ZHANG Yage, XIE Yali, Mahemuti·ABULAITI
2016, 37(9):  77-81.  doi:10.7506/spkx1002-6630-201609015
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The comprehensive evaluation of 20 fruit quality attributes including 6 appearance indices and 14 inherent
nutritional qualities was carried out on 3 superior clones of Zizyphus jujuba cv. Huizao based on factor analysis. The results
showed that different clones of Zizyphus jujuba cv. Huizao had different degrees of variation in fruit quality indices, with
only small variations observed in the percentage of edible portion, horizontal diameter and fruit shape index and relatively
large variations in sugar/acid ratio and the contents of reducing VC, soluble proteins, flavonoids, zinc and copper. Factor
analysis extracted 3 common factors with characteristic roots > 1 and a cumulative variance contribution rate of 100%, which
could fully reflect the information on the fruit quality. ‘Huizao’ clone 1 was evaluated to score highest for overall sensory
quality, followed by clone 7. Both clones belonged to a larger and longer fruit with high sugar content and sweet taste. The
overall sensory score of clone 8, which belonged to a smaller fruit with low sugar content and acidic taste, was lower than
that of clone 7. The three clones showed advantages in terms of different individual indicators.

Analysis of Moisture Change during Far-Infrared Drying of Agaricus bisporus
LIU Zongbo, ZHANG Zhongyuan, LI Dajing, LI Dehai, JIANG Ning, LIU Chunquan
2016, 37(9):  82-86.  doi:10.7506/spkx1002-6630-201609016
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The moisture distribution and change of Agaricus bisporus during far-infrared drying was analyzed by lowfield
nuclear magnetic resonance (NMR) technology. Agaricus bisporus slices (3, 5 and 7 mm thickness) were dried at
three different temperatures (50, 60 and 70 ℃). Results showed that the water states in Agaricus bisporus included free
water, immobilized water and bound water. Free water (M23) was the most dominant among the three water states, which
was 9 048.26, 12 038.71 and 17 532.27, respectively, for 3, 5 and 7 mm thick Agaricus bisporus slices. The removal of free
water and immobilized water from 3 mm thick Agaricus bisporus slices was the fastest at the same drying temperature.
The contents of free water and immobilized water in Agaricus bisporus slices were decreased gradually with increasing
temperature, independent of the thickness of slices, while the content of bound water had no obvious downtrend at different
temperatures. These findings indicated that free water and partial immobilized water were mainly removed during the drying
process, and bound water was hardly removed. Thus, the content of bound water had no significant effect on Agaricus
bisporus during far infrared drying.

Characteristics of Cesium Accumulation in Edible Portion of Three Crops
LAI Jinlong, FU Qian, TAO Zongya, HE Jiao, LUO Xuegang
2016, 37(9):  87-91.  doi:10.7506/spkx1002-6630-201609017
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Pot experiments were carried out to simulate cesium (Cs) pollution in soil (varying doses of Cs were set to 0, 25,
50 and 100 mg/kg) and to explore the characteristics of Cs accumulation and the pollution situation in the edible portion of
three crops (Vicia faba L., Brassica napus L., and Brassica juncea L.) within different growth stages. Results showed that
all three crops were able to uptake Cs efficiently, and their Cs accumulation capacity displayed the following sequence:
Brassica juncea L. > Brassica napus L. > Vicia faba L.. In the seedling stage, the pollution index (PI) of Cs in different
organs (root, stem, and leaf) were all greater than 3 when Cs+ was more than 50 mg/kg, indicating that these organs had been
heavily polluted by Cs. In the squaring stage, Cs accumulation in different organs of three crops increased significantly with
the increase in Cs concentration (P < 0.05), reaching a level higher than that at the seedling stage. The pollution index (PI)
of Cs in most organs investigated were greater than 3 when Cs+ was more than 25 mg/kg, indicating serious Cs pollution in
these organs. In the maturity stage, 9.62%?10.93% of Cs was found to be accumulated in the seeds of the three crops. When
Cs+ was more than 25 mg/kg, these seeds were at moderate and above pollution levels.

Evaluation of Free Radical Scavenging Ability and Antioxidant Activity of Flavonoids from Choerospondias axillaris Fruits Using Cell Model  
YANG Yunshu, JIANG Zitao, LI Rong
2016, 37(9):  92-97.  doi:10.7506/spkx1002-6630-201609018
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Flavonoids from the dried fruits of Choerospondias axillaris were separated using preparative chromatography
into two fractions (F1 and F2). The total antioxidant capacity, and DPPH radical, hydroxyl radical and superoxide anion
radical scavenging activities of F1 and F2 were evaluated using ascorbic acid (VC) as the reference. The results demonstrated
that total flavonoids from C. axillaris had obvious antioxidant capacity, which was between F1 and F2. The DPPH radical
scavenging activity of F1 and the hydroxyl radical scavenging activities of F1 and F2 were higher than those of VC, but total
antioxidant capacity and superoxide anion radical scavenging activity of F1 and F2 were lower than those of VC. In addition,
as evaluated using cell model, the flavonoids from C. axillaris showed significant antioxidant activity in mouse macrophages
(RAW264.7).

Effect of Different Drying Methods on Quality of Lotus Seeds
ZHOU Mingqian, LIU Chunquan, LI Dajing
2016, 37(9):  98-104.  doi:10.7506/spkx1002-6630-201609019
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The effects of 5 drying methods including hot air drying, vacuum microwave drying, vacuum freeze drying, hot
air combined with vacuum microwave drying and hot air combined with explosion puffing drying on physical properties,
major nutritional components and microstructure of dried lotus seeds were studied. The results showed that color difference
value of dried lotus seeds decreased in the order of vacuum freeze drying, hot air combined with explosion puffing drying,
hot air drying, vacuum microwave drying, and hot air combined with vacuum microwave drying; hardness decreased in
the order of hot air drying, vacuum microwave drying, hot air combined with vacuum microwave drying, hot air combined
with explosion puffing drying and vacuum freeze drying; crispness increased in the order of vacuum freeze drying, vacuum
microwave drying, hot air drying, hot air combined with vacuum microwave drying and hot air combined with explosion
puffing drying; specific volume decreased in the order of vacuum freeze drying, hot air combined with explosion puffing
drying, hot air combined with vacuum microwave drying, vacuum microwave drying and hot air drying; rehydration capacity
decreased in the order of vacuum freeze drying, hot air combined with explosion puffing drying, hot air combined with
vacuum microwave drying, vacuum microwave drying and hot air drying. There was very little difference in the contents
of protein and crude fibers in lotus seeds dried by the 5 drying methods. The microstructure of lotus seeds dried by vacuum
freeze, hot air combined with vacuum microwave drying and hot air combined with explosion puffing drying revealed
obvious honeycomb structure, but there was a small amount of gaps in the seeds dried by vacuum microwave, and hot airdried
products had compact structure. Overall, hot air combined with explosion puffing drying can be used as a suitable
processing method for the development of snack foods containing lotus seeds.

Effects of Drying Method and Storage Time on Nutritional Quality and Antioxidant Activity of Walnut Male Flowers
ZHANG Wene, WANG Changlei, SHI Binbin, PAN Xuejun
2016, 37(9):  105-110.  doi:10.7506/spkx1002-6630-201609020
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The effects of drying methods and storage time on the contents of nutritional components, mineral elements,
amino acids and bioactive compounds and antioxidant activity in walnut male flowers (Juglans sigillata ‘Qianhe-7’) were
investigated. The results indicated that oven drying led to higher contents of fat, soluble sugars, starch, titratable acid, total
phenols, total flavonoids and 15 amino acids in dried walnut male flowers than shade air drying, while retaining higher
antioxidant activity although there was no significant difference between two drying methods in the contents of ash, mineral
elements, crude fibers, and amino acids such as Gly and Leu. Our results also showed there were no obvious changes with
storage time in terms of the contents of all nutritional compounds and antioxidant activity except some amino acids such as
Phe, Try, Cys, Lys and Arg in both dried samples.

Spectral Assignment of Dynamic Structure Information of Porcine Myocardial Metmyoglobin (pMetMb)
LI Yadong, WU Mingcao, TANG Yu, JIN Bangquan, HUANG Heyong, LI Gang, FENG Yuying
2016, 37(9):  111-116.  doi:10.7506/spkx1002-6630-201609021
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The dynamic molecular structures and domains of porcine myocardial metmyoglobin (pMetMb) were studied
and analyzed by scanning electron microscopy, X-ray diffraction, Raman and Infrared spectroscopy with matched databases
and softwares. Obviously prismatic crystalline structures were observed on the surface of lyophilized pMetMb powder. The
crystallinity of pMetMb was (95.60 ± 1.37)%, and it was highly crystalline and monoclinic powder because the lengths of its
three-dimensional unit cell were inequality (a ≠ b ≠ c). By comparison with crystal databases the source of heme-Fe domain
in pMetMb was identified. The Raman and Infrared spectra proved that the peptide chain of pMetMb contained 50% α-helix,
14% β-fold, 24% β-turn and 12% random coil, which came from the different shake forms C=O, C=C, C-N, -COO-,
C-H and N-H in the amide I, II and III regions. The heme-Fe domain in pMetMb formed by imidazole group (C3H4N2)
binding with Fe3+. So it belonged to globin with compact structure and stable properties.

Effect of Extraction Temperature on Physical and Chemical Properties of Gelatin from Silver Carp Skin
JI Congling, LU Jianfeng, Lü Shun, JIANG Shaotong, LIN Lin
2016, 37(9):  117-122.  doi:10.7506/spkx1002-6630-201609022
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Gelatin was extracted from silver carp (Hypophthalmichthys molitrix) skin, and the physical and chemical
characteristics of gelatin extracted at different temperatures (30, 50, 70, 90 and 100 ℃) were compared. The maximum
ultraviolet absorption peaks of all gelatin appeared near 218 nm. The maximum gelatin recovery ((86.91 ± 0.98) %) was
obtained when extraction was performed at 90 ℃, while the maximum gel strength ((896.75 ± 117.03) g) was obtained when
the extraction temperature was 50 ℃. The SDS-PAGE pattern indicated that gelatin extracted at 30 and 50 ℃ contained
α1, α2 and β chains, while that extracted at 70, 90 and 100 ℃ did not have obvious bands, which was presumably ascribed
to heat degradation of gelatin. The thermal denaturation temperatures of the gelatin extracted at 30, 50, 70, 90 and 100 ℃
were (97.88 ± 2.65), (108.66 ± 0.43), (106.48 ± 3.33), (100.27 ± 2.37) and (99.56 ± 0.37) ℃, respectively. The higher the
extraction temperature was, the smaller the values of G’ and G’’ were, and the worse rheological properties of gelatin were.

Comparative Study on Physicohemical Characteristics and Flavone Dissolution Properties of Mulberry Leaf Powder with Different Particle Sizes
HE Yun, FAN Ziwei, WU Yu, ZHONG Geng
2016, 37(9):  123-128.  doi:10.7506/spkx1002-6630-201609023
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Basic physicochemical characteristics of mulberry leaf powder with different particle sizes were compared
including particle diameter, microscopic features, infrared spectral information, comprehensive characteristics, water and
oil holding capacity and expansibility, as well as dissolution pattern of flavones with the aim of helping exploit and utilize
mulberry leaves. Results from microscopic observation and infrared spectroscopic analysis demonstrated that cell walls
of mulberry leaves were crumbled after superfine grinding while the main chemical constituents remained unchanged. On
the other hand, flowability, expansibility and water and oil holding capacity were all declined with the decrease in particle
size. Dissolution tests indicated the smaller the particle size of mulberry leaf powder was, the larger amount of flavones was
dissolved out. In addition, simulated intestinal juice contributed to better dissolution of flavones than gastric juice. Based on
dynamic analysis, the corresponding kinetic models were established to describe the dissolution of flavones from mulberry
leaf powder with different particle sizes.

Growth Pattern and Storage Performance of ‘Jinyan’ Kiwi Fruits
WANG Qikai, YANG Dan, ZHANG Xiaoqin, ZHANG Xinwang
2016, 37(9):  129-133.  doi:10.7506/spkx1002-6630-201609024
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The growth pattern and storage performance of ‘Jinyan’ kiwi fruits were studied by continuously measuring the
size of developing fruits in the field and the quality of the fruit during growth and postharvest storage. The results showed
that the growth pattern of vertical diameters, transverse diameters, weight and dry matter of fruits revealed a gradually rising
trend during fruit growth from day 7 to 175 after withering. The soluble solids content rose slowly during the early growth
stage, showing significant fluctuations, but rapidly declined during day 140 to 175. The h0 value of pulp color throughout
the entire fruit growth process gradually decreased. ‘Jinyan’ kiwi fruits entered the harvest period 175 days after withering,
when the soluble solids content was 7.5%?8.0%. In addition, the fruis showed good storability and the firmness decreased to
10.01 N/cm2 after storage for 150 days at 0?1 ℃ and RH of 90%?95%. Therefore, our data demonstrate that drought can
reduce the individual fruit weight and dry matter content of ‘Jinyan’ kiwi fruits, thereby impacting fruit yield and quality.

Anthocyanins from Purple Sweet Potato (Ipomoea batatas) and Its Application in VC Quantification
GUO Caihua, LU Zhenhua, WU Ling, CHEN Zhaohua, CHEN Qingchou, XIONG Hejian
2016, 37(9):  134-138.  doi:10.7506/spkx1002-6630-201609025
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Anthocyanins were extracted from purple sweet potato (Ipomoea batatas) using an environmentally friendly
process. The anthocyanins exhibited characteristic absorption peak at 530 nm, having a molecular weight in the range of
850?1 020 u. The content of vitamin C in Valencia orange and tomato was determined by a new titration method using the
anthocyanins extracted from purple sweet potato in place of 2,6-dichloroindophenol as described in the Chinese national
standard GB/T 6195-1986. The results showed that vitamin C was (25.33 ± 0.34) mg/100 g in Valencia orange and (20.41 ±
0.32) mg/100 g in tomato. The spiked recoveries of VC with purple sweet potato anthocyanins ranged from 95.4% to 98.6%,
with relative standard deviation (RSD) of 1.18%?1.22%, while those with 2,6-dichloroindophenol titration were between
96.5% and 98.7% with RSD of 0.86%?0.88%. The anthocyanin titration method was safe and low-cost with an accuracy
equivalent to that of 2,6-dichloro-indophenol titration.

Fluorescence Spectroscopic Study of the Interaction of Lysozyme with Bacitracin
NI Zhihua, ZHANG Yuming, DENG Chuanhuai, ZHOU Yanfen
2016, 37(9):  139-143.  doi:10.7506/spkx1002-6630-201609026
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The interactions between bacitracin and lysozyme were studied by fluorescence spectroscopy. The results showed
that the intrinsic fluorescence of lysozyme could be quenched by bacitracin. The fluorescence quenching of lysozyme
was analyzed at different temperatures. The quenching mechanism was accomplished in a static manner by forming a
bacitracin-lysozyme complex. The binding parameters were determined according to Stern-Volmer equation, and the
thermodynamic parameters were calculated. The results showed that there was only one binding site between bacitracin and
lysozyme. The binding constants (KA) between bacitracin and lysozyme at different temperatures were 3.60 × 105 (298 K),
1.90 × 105 (308 K), and 4.51 × 104 L/mol (318 K), respectively. Thermodynamic analysis indicated that the interaction
process was spontaneous, and electrostatic force might be primarily responsible for the interaction. In addition, the effect
of bacitracin on the conformation of lysozyme was analyzed by three-dimensional fluorescence spectroscopy. The result
indicated that the polarity of the microenvironment around Trp residues decreased.

Effect of Sterilization Methods on the Quality of Mulberry Juice
WU Qiong, FENG Weimin, JIANG Heti
2016, 37(9):  144-149.  doi:10.7506/spkx1002-6630-201609027
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A comparative analysis of the effect of three different sterilization methods, namely pasteurization, ultra high
temperature treatment (UHT) and ultra high hydrostatic pressure (UHHP), on the microbial load, quality and aroma
composition of mulberry juice was carried out in the present investigation. The results indicated mulberry juice met the
requirement of commercial sterilization according to the Chinese national standard GB 19297—2003 after being sterilized
by the above three methods, especially by UHT treatment, which achieved complete microbial inactivation. Compared
with the blank group, soluble solids and total sugar contents significantly decreased (P < 0.05) after pasteurization and
UHT treatment. UHHP treatment had the largest impact on the content of anthocyanins. The content of total phenol
and flavonoids, and antioxidant capacity declined to different extents after different sterilization treatments, and UHHP
treatment changed the least. As indicated by solid-phase micro-extraction (SPME) coupled with gas chromatography-mass
spectrometry (GC-MS), 52, 42, 44 and 49 volatile aroma components were identified in the blank control and mulberry
juice subjected to pasteurization, UHT and UHHP treatments, respectively. UHHP treatment was the most close to the blank
group as far as the main aroma components were concerned. In general, UHHP technology has good sterilization efficiency
while effectively maintaining the quality of mulberry juice.

Bioengineering
Corroboration of Quinolone Resistance Mediated by Active Efflux System in Lactic Acid Bacteria
LI Zhen, LI Shaoying, SONG Xiaomin, MA Chunyan, LI Shufen, HE Wenying, CAO Yinghua
2016, 37(9):  150-154.  doi:10.7506/spkx1002-6630-201609028
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Purpose: In this study, lactic acid bacteria (LAB) were separated from horse milk and horse milk products with
national characteristics and special functions in pastoral areas of Inner Mongolia. In order to ensure better application of
the isolated strains in the fermentation industry, it is necessary to test their drug resistance and explore if LAB possess an
active efflux system mediating quinolone resistance. Methods: Double dilution method was used to determine the minimum
inhibitory concentration (MIC) of quinolone. The proton pump inhibitor reserpine was combined with fluorescence
spectrophotometry to detect the ciprofloxacin intakes of drug-resistant strains and control strains. Results: The accumulation
of ciprofloxacin increased significantly in drug-resistant strains HZ18, HZ28, NN3 and NN4 after adding reserpine.
Conclusion: Lactic acid bacteria may possess an active efflux system mediating quinolone resistance.

Preparation and Identification of a Black Soybean Lipoxygenase
LI Ru, CUI Xiaodong, LI Yuying, LI Chen, WANG Zhuanhua
2016, 37(9):  155-159.  doi:10.7506/spkx1002-6630-201609029
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Objective: To extract and purify black soybean lipoxygenase (bsLOX) containing β-glucosidase activity and
investigate its anthocyanins-degrading properties and enzymatic activity. Methods: Purification of bsLOX was carried
out by buffer extraction, ammonium sulfate precipitation, dialysis, cation exchange chromatography and gel filtration
chromatography. The activities of lipoxygenase and β-glucosidase in bsLOX were analyzed by using sodium linoleate and
p-nitrophenyl β-D-glucopyranoside (pNPG) as substrates, respectively. An LOX from black soybean seeds was obtained,
which showed a single band in SDS-PAGE, with approximate molecular weight of 95 kD. The purified protein had a
lipoxygenase activity of approximately 13 U/mL, and could produce nitro phenol using pNPG as substrate as detected at
405 nm, suggesting that bsLOX had β-glucosidase activity. HPLC results showed that bsLOX could only degrade part of
anthocyanins (cyanidin-3-O-glucoside and petunidin-3-O-glucoside) into aglycone anthocyanidins (cyanidin and petunidin)
and glucose; in turn, the residual anthocyanidins could inhibit the activity of bsLOX. Conclusion: LOX in black soybean
may be a kind of protein with a variety of enzymatic functions, while anthocyanidins may be a natural bsLOX inhibitor.

Effects of Exogenous Substances on the Content of Secondary Metabolites in Arnebia euchroma Johnst Hairy Roots
GE Sunan, ZHANG Shengxuan, WANG Fang, WEI Huan, XIE Wenlei, XIE Jian, LI Chi, ZHAO Hu
2016, 37(9):  160-164.  doi:10.7506/spkx1002-6630-201609030
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Objective: To investigate the effects of different exogenous substances on the content of secondary metabolites in
Arnebia euchroma Johnst hairy roots and consequently provide a theoretical basis for further development and utilization of
Arnebia euchroma Johnst hairy roots. Methods: The contents of secondary metabolites were measured by spectrophotometry
from Arnebia euchroma Johnst hairy roots cultured in the presence of AgNO3 alone and in combination with L-phenylalanine
or L-phenylalanine plus sodium acetate. Results: The contents of shikonin, total polyphenols and total flavonoids in hairy
roots cultured for 30 days at an AgNO3 concentration of 5 mg/L respectively increased by 6, 1.3, 1.8 times compared with
the control (CK). In addition, when AgNO3 concentration was 3 mg/L, the anthocyanin content reached its peak, a 1.4-fold
increase over the control. Peak contents of shikonin, anthocyanins and total flavonoids were observed after culture in the
presence of both 25 mg/L L-phenylalanine and 5 mg/L AgNO3, which were increased by 1.3, 2.4 and 2.2 times, respectively,
compared with the CK. The content of total polyphenols was not higher than that in the CK, but it was still the highest among
three treatment groups. The contents of shikonin and total polyphenols reached their highest levels at 50 mg/L among different
sodium acetate concentrations combined with 5 mg/L AgNO3 and 25 mg/L L-phenylalanine, whereas the highest content of
anthocyanin was observed when the sodium acetate concentration was 200 mg/L. The content of total flavonoids in hairy
roots with sodium acetate treatments at various concentrations was significantly lower than that of the control. Conclusion:
The addition of AgNO3 and L-phenylalanine can cooperatively promote the accumulation of secondary metabolites in
Arnebia euchroma Johnst hairy roots. Meanwhile, AgNO3, L-phenylalanine and sodium acetate can cooperatively promote
the accumulation of shikonin, polyphenol and anthocyanin, but significantly inhibit the accumulation of total flavonoids.

Effect of Redox Potential Regulation on Metabolic Flux Distribution of Corynebacterium crenatum
CHEN Xiaoju, CAO Xinmin, JIANG Shaotong, LI Xingjiang
2016, 37(9):  165-169.  doi:10.7506/spkx1002-6630-201609031
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For the co-production of lactic acid and succinic acid, the effect of redox potential regulation on the fermentation
process of Corynebacterium crenatum was studied and the metabolic flux distribution was also analyzed. When the redox
potential level was changed from −56 to −400 mV, the concentration of succinic acid in the fermented broth increased from
14 to 20.2 g/L;meanwhile, the concentration of lactic acid decreased from 44.9 to 35.2 g/L. The results of metabolic flux
analysis indicated the metabolic flux distribution at the glucose 6-phosphate and phosphoenolpyruvate nodes were affected
significantly. Compared with the value obtained at -56 mV, the flux of pentose phosphate pathway (HMP) pathway increased
by 2.74 fold and the flux from phosphoenolpyruvate to oxaloacetate increased by 78%. As a result, the flux of succinic acid
increased from 31.73 to 56.53 mmol/(L·g·h) and the flux of lactic acid decreased from 159.73 to 133.50 mmol/(L·g·h).
The results of this study demonstrated that glucose 6-phosphate and phosphoenolpyruvate were the key nodes that could
affect the production of succinic acid by C. crenatum fermentation under anaerobic conditions, which has contributed to the
co-production of lactic acid and succinic acid by manipulating wild-type C. crenatum to change the ratio of succinic acid/
lactic acid through metabolic engineering.

Separation and Determination of Angiotensin Converting Enzyme Inhibitory Peptide from Salt-Soluble Protein Solution Fermented with Lactic Acid Bacteria
ZHAO Junliang, LU Haipeng, MANG Lai, JIN Shan
2016, 37(9):  170-174.  doi:10.7506/spkx1002-6630-201609032
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Sixteen lactic acid bacteria (LAB) strains were cultured for 3 generations in MRS liquid medium, centrifuged,
prepared into LAB suspension with sterilized physiological saline, and then inoculated in salt-soluble protein (SSP) solution
from arabesque greenling. Through determining angiotensin converting enzyme (ACE) inhibitory peptide from metabolites,
Pediococcus acidilactici ID7 and Lactobacillus plantarum 6214 displayed high ACE inhibitory activity, with a percentage
inhibition of 47.6% and 40.6%, respectively. Higher ACE inhibitory activity in SSP solution fermented with Pediococcus
acidilactici ID7 was determined by high performance liquid chromatograph (HPLC). Meanwhile, two peaks after HPLC
purification were achieved, which showed IC50 of 1.21 μg/mL and 1.07 μg/mL, respectively. The peak with higher ACE
inhibitory activity was purified by gel filtration. The obtained ACE inhibitory peptide showed percentage inhibition of
26.67% and molecular weight less than 586.7 D.

Screening, Isolation and Identification of Acid-Degrading Yeast from Vaccinium vitis-idaea Wine
YANG Hua, LIU Yana, GUO Dejun
2016, 37(9):  175-180.  doi:10.7506/spkx1002-6630-201609033
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A yeast strain with high acid-degrading ability from Vaccinium vitis-idaea juice fermented in a
a thermostatically controlled incubator at 24 ℃ was isolated and identified. Its acid degradation capacity was investigated.
The results indicated that strain BY-9, which had the highest acid-degrading capacity, was found to be the most suitable for
reducing acidity of Vaccinium vitis-idaea wine. Based on morphological and physiological characterization, and internally
transcribed spacer (ITS) analysis, strain BY-9 was identified as Zygosaccharomyces bisporus. The total acid content of
Vaccinium vitis-idaea wine was reduced by 12.26% when BY-9 was inoculated after alcoholic fermentation.

Effects of Salicylic Acid, Methyl Jasmonate and Ultrasound on the Production of Cumarins and Growth of Radix Glehniae Callus
MIAO Xiaoyan, ZHU Weihong, ZHANG Xiaomei, WANG Lin
2016, 37(9):  181-185.  doi:10.7506/spkx1002-6630-201609034
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The effects of methyl jasmonate (MeJA), salicylic acid (SA) and ultrasonic treatment on the production of
cumarins (imperatorin, isoimperatorin and psoraleae as measured by HPLC) and growth of callus tissue of Radix Glehniae
were explored. The results showed that SA and MeJA could cause growth inhibition in callus tissue, while low-intensity
ultrasound treatment for a certain time had a positive effect on callus vitality. Additionally, the production of cumarin could
be promoted to different extents by all three factors. When the concentration of salicylic acid was 8 mg/L, the content of
imperatorin reached its maximum level, which was 3.8 times higher than the control, but SA had only a marginal impact on
psoralen. When the concentration of salicylic acid increased to 16 mg/L, the production of psoralen reached its maximum
level, which was 1.7 times higher than the control. When the concentration of salicylic acid further rose to 28–30 mg/L,
the maximum content of isoimperatorin and total cumarins was achieved showing a 2.33-fold increase compared with the
control. The MeJA concentration of 400 μmol/L resulted in maximum production of psoralen and isoimperatorin, which
was increased by 6.09 and 5.53 times in comparison with the control, respectively; meanwhile the maximum content of
total cumarins was observed, which was 5.11 times higher than that of the control. After ultrasound treatment for 30 min,
the production of imperatorin, isoimperatorin and total cumarins reached their maximum levels (5.51, 3.69 and 11.90 μg/g),
which were 5.15, 4.20 and 3.55 times higher than those of the control, respectively; when ultrasonic treatment lasted 10 min,
the maximum production of psoralen was found, which was 1.5 times higher than that of the control. In summary, compared
with ultrasonic treatment and SA, MeJA could more effectively promote the production of coumarins in Radix Glehniae.

Isolation, Screening and Identification of Lactic Acid Bacteria with Conjugated Linoleic Acid-Producing from Traditional Cream Products in Xilingol League of Inner Mongolia
LIU Chunxiao, LI Jiayu, LIU Naiqi, LIU Lijie, ZHANG Jianli, BAI Ying
2016, 37(9):  186-191.  doi:10.7506/spkx1002-6630-201609035
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The objective of this study was to isolate lactic acid bacteria (LAB) with high ability to produce conjugated
linoleic acid (CLA) from traditional cream products in Xilingol League of Inner Mongolia. CLA content in fermented
broth was determined by UV-spectrophotometry, and the strains with the highest CLA-producing ability were identified by
analyzing their colony characteristics, cell morphology, biochemical and physiological characteristics, and the phylogenetic
tree generated with MEGA 6 software based on 16S rDNA sequence. Twenty CLA-producing strains were isolated from
traditional cream products, 11 strains of which were present in samples collected from Xianghuang Banner and the remaining
9 strains were found in samples collected from Zhengxianglan Banner. HS4 with the highest CLA-producing capacity among
the strains isolated from cream samples collected from Xianghuang Banner was identified as Lactobacillus casei, producing
23.586 μg/mL CLA with a conversion efficiency of 7.86% when it was cultured at an inoculum size of 2% in the presence
of 0.06% linoleic acid; among the strains isolated from cream samples collected from Zhengxianglan Banner, LX5 with the
highest CLA-producing capacity was identified as Lactobacillus paracasei, producing 20.508 μg/mL CLA with a conversion
efficiency of 6.84% under the same culture conditions as described for HS4.

Nutrition & Hygiene
Effect of Lyophilized Natto Powder on Antibiotics-Mediated Immunomodulation and Cytokine Secretion in Mice
WU Gaofeng, HUANG Zhanwang, LIU Wanling, NIU Liya, WANG Suzhen, HUANG Yongping
2016, 37(9):  192-197.  doi:10.7506/spkx1002-6630-201609036
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The effect of natto lyophilized powder (NLP) on antibiotics-mediated immunomodulation and cytokine secretion
in SPF mice was explored in the present study. Totally 128 healthy mice were selected and divided randomly into 8 groups:
control group (C), four regulation groups (RN0, 1, 2 and 3), two prevention groups (P0 and PN), and model group (M).
The mice in all groups except C were administered with antibiotic solution for 3 days. Thereafter, the mice from group R0
were gavaged with normal saline, while those from group RN1, 2 and 3 were given NLP solution at three different dosages,
respectively. The mice from the two prevention groups were continuously daily administered with antibiotic solution; 8 hour
later, groups P0 and PN were respectively lavaged with normal saline and NLP solution. The mice in group M were simply
given antibiotic solution during the entire administration period of 30 days. Immunomodulatory effects of NLP in mice and its
effect on cytokine secretion were determined. Results showed that low-dose NLP resulted in a significant elevation in spleen
and thymus indices in mice compared with the model group (P < 0.01). The production of serum IL-2, IL-10, TNF-alpha,
and IFN-gamma extremely significantly increased in groups RN1, RN2 and RN3 compared with the model group
(P < 0.01). In addition, the mice from the three prevention groups showed an extremely significant increase in inducible
nitric oxide synthase (iNOS) activity in serum (P < 0.01), and serum albumin and globulin concentrations and their ratio
as well as serum NO level were significantly or extremely significantly higher in the mice from groups RN1 and RN3
(P < 0.05 or P < 0.01). The serum hemolysin levels in mice from the control, regulation and prevention groups were
significantly higher than those in the group N (P < 0.01). The phagocytic capacity of peritoneal macrophages from mice in
groups RN1, RN2, RN3 and PN was significantly higher than that of group M. Compared with the control group, the half
value of hemolysis (HC50) in groups RN1, RN2 and RN3 was significantly or extremely significantly increased (P < 0.05
or P < 0.01). Groups RN3 and PN exhibited an extremely significant increase in the percentage of macrophages engaged
in phagocytosis and the percent phagocytosis of chicken red blood cells (P < 0.01). Therefore, NLP can enhance immune
function and increase the secretion of cytokines.

Fluorescence Detection of the Entry of Cyanidin-3-O-Glucoside into Macrophages
ZHANG Yinghui, WANG Bingyun, HUANG Jianbo, JI Huiqin, MA Yanling, ZHONG Xiqiong, DONG Huaqiang
2016, 37(9):  198-202.  doi:10.7506/spkx1002-6630-201609037
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The distribution of cyanidin-3-O-glucoside (C3G) in cultured mouse and human macrophages was detected
with fluorescence technique. First, the specific excitation wavelength and emission wavelength of C3G were scanned with
fluorescence spectrophotometric assay. Then, a confocal laser scanning microscopy was utilized to investigate the entry
process of C3G into cultured mouse macrophages and human macrophage THP-1 cells, and to trace the location of C3G as
well as the change in fluorescence intensity in the cells during incubation. The results showed that green and red fluorescence
in macrophages after 15 min C3G incubation could be detected with light excitation at 488 nm and 520 nm, respectively. The
fluorescence signals were enhanced in the cells as the incubation time was prolonged. The special fluorescence appeared in
nuclei when the cells were treated with C3G for 60 min, and the average fluorescence intensity was enhanced by 6.45 folds
when C3G incubation time was increased up to 60 min. These results indicated that the distribution of C3G in cells during
incubation could be traced with laser scanning confocal microscopy assay. It was concluded that C3G could pass rapidly
through the cell membrane and nuclear membrane of macrophages, and entered directly the cell nucleus.

Effect of Juglans mandshurica Maxim Kernel Protein Isolate on Alleviating Physical Fatigue in Mice
CUI Lingyu, MIN Weihong, LIU Wei, MAO Jing, MIAO Xinyu, LIU Jingsheng
2016, 37(9):  203-207.  doi:10.7506/spkx1002-6630-201609038
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To explore the anti-fatigue effect of Juglans mandshurica Maxim kernel protein isolate (JMKP), weight-loaded
swimming test of mice was carried out and exhaustive swimming time as an indicator of fatigue, blood lactate (BLA)
content, hepatic glycogen (HG) content, malondialdehyde (MDA) content, and the activities of glutathione peroxidase
(GSH-Px), catalase (CAT) and superoxide dismutase (SOD) were determined. The results showed the exhaustive
swimming time of mice gavaged for 2 weeks with JMKP at high dose increased by 38.66% compared with controls, and
4-week administration at low, medium and high doses resulted in a 24.10%, 42.17% and 64.46% compared with controls,
respectively. The BLA content of mice in the high-dose JMKP group administered for 2 weeks decreased by 21.44%, and
that of mice from the medium-dose and high-dose JMKP groups administered for 4 weeks decrease by 13.02% and 23.48%,
respectively, compared with controls. The GLU content of mice from the medium-dose and high-dose JMKP groups
administered for 2 and 4 weeks increased by 15.41%–16.29% and 18.35%–20.81%, respectively compared with controls.
High-dose administration of JMKP for 2 and 4 weeks led to a 20.41% and 28.59% in serum MDA content, respectively. The
levels of GSH-Px, CAT and SOD activity could be significantly improved by JMKP administration, especially for 4-week
high-dose JMKP compared with controls (P < 0.01). Therefore, JMKP could evidently alleviate physical fatigue in mice.

Genotoxicity Evaluation of Violacein and Deoxyviolacein by umu Test
SUN Yong, ZHANG Jinlan, LIU Hongru, LI Gang, ZHANG Chong, XING Xinhui, CHEN Ning, WANG Shouwei
2016, 37(9):  208-213.  doi:10.7506/spkx1002-6630-201609039
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Objective: Violacein and deoxyviolacein are bacteria-originated indole compounds with diverse bioactivities.
This study aimed to investigate the genotoxicity of violacein, deoxyviolacein and their combination, and provide the basis
for the exploration of their applications. Methods: The SOS repairing of Salmonella typhimurium NM2009 cells induced
by violacein, deoxyviolacein, their combination or S9 metabolites was quantitatively analyzed by SOS/umu detection kits.
Meanwhile, the toxicity of violacein, deoxyviolacein, their combination and S9 metabolites as well as the positive control
drugs such as 2-aminofluorene (AF-2) and 2-aminoanthracene (2-AA) was compared. Results: It was demonstrated that
32.6 μg/mL deoxyviolacein, S9 metabolites of 34.2 μg/mL violacein and 33.4 μg/mL combination had genotoxicity for
Salmonella typhimurium NM2009 cells, but they all showed lower genotoxicity compared with positive control. Moreover,
violacein, deoxyviolacein and their combination at the same dosage exhibited similar toxicity without synergistic effect.
Conclusion: Violacein and deoxyviolacein have weak genotoxicity.

Reviews
Progress in Research on Biofilm Formation by Probiotics
LIU Lei, LIU Yi, LI Pinglan
2016, 37(9):  214-219.  doi:10.7506/spkx1002-6630-201609040
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Probiotics are defined as ‘live microorganisms which when administered in adequate amounts confer health
benefits to the host’. In recent years, probiotics have gained increasing attention due to their therapeutic effects. Biofilms are
formed by multiple bacterial cells attached to a surface that arranges themselves into a complex tertiary structure encased
in an extracellular matrix comprised of carbohydrates, proteins, and other macromolecules, which constitute the majority of
bacteria in most natural ecosystems. However, little research has been done concerning probiotic biofilms. Therefore, the
formation, characteristics, influencing factors, advantages and regulatory pathways of probiotic biofilms are discussed in this
paper. In the future, probiotic biofilms will be an important research area.

Research Progress on Phosvitin in the Regulation of Biomineralization
JIE Yilin, CHEN Chan, LIU Qingli, MA Meihu, HUANG Xi
2016, 37(9):  220-226.  doi:10.7506/spkx1002-6630-201609041
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Recent studies have found that phosphoprotein plays a very important role in biomineralization, and phosvitins possess
the highest phosphorylation level among all known proteins in eggs. Phosvitin was speculated to possess regulatory effects on
biological mineralization according to some previous studies, but the mechanism and active sites for regulation of mineralization
are still unclear. This paper gives a brief overview of where, how and why biomineralization occurs and the way biomineralization
is regulated. Recent hypotheses regarding the regulation of biomineralization by phosvitin are also discussed.

Advances in Hypoglycemic and Hypolipidemic Mechanisms of Capsaicin
WANG Yuanwei, LIU Xiong
2016, 37(9):  227-231.  doi:10.7506/spkx1002-6630-201609042
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Capsaicin is a vanilla amides alkaloid which is an active ingredient in chili peppers. Much recent research has
demonstrated the hypoglycemic and hypolipidemic activity of capsaicin. This paper reviews recent progress in the research
on the hypoglycemic and hypolipidemic mechanisms of capsaicin involving binding to the capsaicin receptor, adjusting
the brown adipose tissue and white adipose tissue, releasing adipose cytokines,altering the gut microbial composition,
modulating food intake and muscle performance, aiming at providing references for further development and applications of
capsaicin as an ingredient of drugs or health products.

Current Progress in the Understanding of the Mechanism of Prevention and Treatment of Lycium barbarum Polysaccharides on Type 2 Diabetes
XIA Hui, TANG Huali, PAN Jiaqi, SUN Guiju
2016, 37(9):  232-236.  doi:10.7506/spkx1002-6630-201609043
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The present review summarizes therapeutic effects of Lycium barbarum polysaccharides (LBP) on type 2 diabetes.
Research indicated that LBP treatment could lower blood glucose and lipid levels, facilitate insulin secretion, attenuate
insulin resistance and increase insulin sensitivity. Furthermore, superoxide dismutase activity (SOD), malondialdehyde
(MDA) level, nitrogen monoxide (NO) content and other oxidative stress indicators could be significantly improved by LBP
administration. The mechanism may be associated with the improvement of pancreas islet function, such as upregulation
of insulin receptor substrate-1 and regulation of genes related to glycometabolism. LBP also has potential preventive and
therapeutic effects on diabetes complications.

Recent Advances in the Control of Aflatoxin Contamination
SHEN Qingshan, ZHOU Wei, MO Haizhen, HU Liangbin
2016, 37(9):  237-243.  doi:10.7506/spkx1002-6630-201609044
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Aspergillus flavus can contaminate crops and food products, and produce aflatoxins which cause extremely serious
damage to human and animal health. In this study, the molecular mechanisms involving aflatoxins biosynthesis, regulation
and transport are reviewed. The existing strategies used to control aflatoxin contamination, such as genetic engineering
and breeding, and physical and chemical decomposition are summarized. Additionally, the development and application of
botanical fungicides and biological interventions are also highlighted and discussed.

Food Quality Traceability System Based on Unified Modeling Language
WANG Xinping, LIU Ping
2016, 37(9):  244-249.  doi:10.7506/spkx1002-6630-201609045
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To realize the traceability and control for food quality information based on relevant studies, this paper analyzes
the requirements for food quality traceability system, and determined its function module. Using unified modeling language
(UML), the system’s business process, static model and dynamic model are visualized. The system model is designed
by means of use case diagram, sequence diagram and class diagram; at the same time, the related business processes are
described by activity diagram.

Progress in Research on Stress Response in Escherichia coli during Food Processing and Storage
SHI Hui, CHEN Zhuozhu, KAN Jianquan
2016, 37(9):  250-257.  doi:10.7506/spkx1002-6630-201609046
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Escherichia coli can sense environmental signals and respond quickly to the changing environment. Therefore,
during food processing and storage, the response of E. coli to physical and chemical stress enables them to survive and
maintain virulence, which poses a great threat to food safety. This paper is focused on summarizing the molecular and
physiological response of E. coli to common stress factors during food processing and storage and its application in the food
industry, including heat shock, cold shock, desiccation, hyperosmotic stress, antimicrobial peptides and acid stress. The
future research direction in this area is also discussed.

Reconsideration of Food Safety Systemic Risks in China from the Perspective of Risk Cognition Dimensions
LI Jiajie, LI Nan, LUO Lang
2016, 37(9):  258-263.  doi:10.7506/spkx1002-6630-201609047
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With the increasing occurrence of food safety incidents, the public has paid more and more attention to food
safety risks. In this study, starting from the theory of systemic risks, we constituted four risk recognition dimensions to
recognize food safety systemic risks. Genetically modified organism (GMO) risk was taken as an example to explain why
the arguments existed for a long time from the viewpoint of four risk recognition dimensions. Our results contributed to
form new cognition views of food safety risks and could provide suggestions for related institutions to carry on effective risk
communication, help the public know food safety risks correctly and avoid unnecessary panic or trust crisis.

Advances in Potato Flavor
GONG Xingwang, GUO Huachun
2016, 37(9):  264-268.  doi:10.7506/spkx1002-6630-201609048
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Potato plays an important role in people’s daily life and health. Potato flavor is a vital component of potato
quality, and it mainly consists of aroma, taste and texture. The aroma is always determined by volatile flavor compounds
such as pyrazine, heptaldehyde and hexanal. The taste of potato is mainly determined by non-volatile compounds such as
nucleotides and amino acids, and the texture is associated with dry matter content and starch content in potato. In addition,
potato flavor is highly related to the potato growing conditions and storage environment. This article mainly focuses on the
recent progress in understanding aroma, taste and texture of potato.

Skin Microbiome and Probiotic Therapeutic Approaches for Skin Diseases
MA Chen, ZHANG Heping
2016, 37(9):  269-273.  doi:10.7506/spkx1002-6630-201609049
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The skin as the largest organ of the human body is colonized by complex microbial communities. Most of them
are harmless, and even beneficial to the human body. Colonization is driven by the ecological environment of the epidermis,
and the skin microbial communities are highly variable because of endogenous host factors, topographical location and
exogenous environmental factors. The skin microbiota can be modulated by the cutaneous innate and adaptive immune
responses. Meanwhile, the skin microbiota can promote the evolution of host’s immune system. With the development of
molecular biological technology, there has been an emerging view of the resident skin bacteria with high variability and
diversity. A deepened understanding of the skin microbiome is essential to gain insight into microbial involvement in human
skin diseases and probiotic therapeutic approaches for their treatment. In this review, we summarize recent studies on skin
microbiome, and also illustrate the application potential of probiotics as a new complementary and alternative medicine in
the diagnosis and treatment of.typical diseases caused by microfloral imbalance.