Free radical models and a microplate reader were used to explore the scavenging activity of apigenin (API) against hydroxyl and DPPH free radicals. The CuSO4-Phen-VitC-H2O2-DNA chemiluminescence system was employed to determine the inhibitory effect of API on hydroxyl radical-induced DNA damage. Meanwhile, the protective effect and possible mechanisms of API with effective concentration against free radical-induced DNA damage were also explored. The results showed that the scavenging rates of API at the doses of 25, 50, 100μg/mL and 20 0μg/mL within 30 min of reaction against DPPH free radicals were 8.80%, 28.4%, 37.4% and 62.8%, respectively. Similarly, the scavenging rates of API at the doses of 200, 100μg/mL and 50μg/mL on hydroxyl free radicals were 50.2%, 35.4% and 25.4%, respectively. The inhibition rate of API at the concentration range of 25－100μg/mL on chemiluminescence of DNA damage products was 5.6%－16.9% and API also resulted in the delay of DNA damage for 35－50 min. API at low dose could eliminate DPPH and OH free radicals obviously, restrain DNA damage induced by free radicals, and delay DNA damage time. The free radical scavenging activity and anti-DNA damage effect of API were both correlated with its concentration.

Salted eggs are important egg products in our country. Sodium chloride (NaCl) is an essential component in the manufacturing of salted eggs, and can improve the structure and texture of eggs and special flavor formation. In this study, potassium chloride (KCl) was added at ratios of 5%, 6.5%, 8.5% and 12.5% as a partial substitute for NaCl to process salted duck eggs and 25% saturated NaCl immersion was used as the blank. Using this mixed method, the amount of salt addition was directly reduced, and partial substitution with KCl could improve the salting process. In addition, the oil release rate of egg yolk, the water contents of egg white and yolk, and the NaCl content, texture, structure, color parameters and microstructure of whole salted eggs were determined and the sensory quality of salted eggs was comprehensively evaluated. The results indicated that 6.5% sodium chloride was the best addition. The NaCl content in egg white protein was decreased from 54.4 to 40.1 mg/g with a range of 26.29%. Sensory evaluation revealed that potassium ions at excess concentrations could result in bitter taste. However, partial substitution of NaCl with KCl did not affect egg texture and the oil release rate and loose sand-like mouthfeel of egg yolk. Therefore, this method is feasible for reducing sodium content.

Fruit juice, wine and vinegar from seven pear cultivars, Yuanhuangli, Whasan, Housui, Crystal, Whangkeumbae, Niitaka and Nansui were physiochemically characterized. Meanwhile, sensory evaluation of seven varieties of pear vinegar was carried out. The cultivar Crystal showed higher juice yield, alcohol degree and acid production than the other six cultivars, and the pear vinegar fermented from it was evaluated to have golden yellow color, pleasant aroma, nice tart/sweet balance and typical pear flavor. Thus, we concluded that Crystal is a more suitable cultivar for making fruit vinegar.

Six texture profile analysis (TPA) parameters of strawberry fruits were measured under varying conditions of test speed, dwell time and compression distance. In addition, different parts of strawberry fruits were compared for differences in six TPA parameters. The results showed that some TPA parameters necessarily varied with each of the three test conditions, and compression distance resulted in the most prominent changes in adhesiveness, resilience and cohesiveness among them. Although different parts of strawberry flesh did not significantly differ in their hardness, adhesiveness or springiness, the middle part exhibited distinctly higher chewiness, cohesiveness and resilience when compared to the bottom part.

Anthocyanin pigments from Rhododendron championae Hook flowers (light red color) were primarily identified and quantified by the specific color reactions and HPLC-MS/MS. Anthocyanins were extracted by grinding with liquid nitrogen. The resulting extract was found to contain non-red flavonoid compounds (mainly flavonoids, flavonols and flavanones) and some phenolic compounds. HPLC analysis demonstrated that the extract contained at least 39 compounds, of which, 7 were identified to be myricetin-3-galactoside, quercetin3-galactoside, quercetin-3-rhamnoside, quercetin-3-glucoside, malva-3-arabinoside-5-glucoside, myricetin-3-rhamnoside and chlorogenic acid, respectively. Rhododendron championae Hook flowers were determined by UV spectrophotometry to contain 131.025 mg/100 g anthocyanin and 10.68 mg/g total flavonoids.

The purpose of the present study was to investigate antioxidant constituents in Eucommia ulmoides Oliv. leaves and deeply exploit the resource. Aqueous extract from the leaves of the plant was separated by sequential solvent extraction into chloroform, ethyl acetate extract and n-butanol fractions as well as extraction residue, and the abilities of the extract and these four fractions to scavenge DPPH and hydroxyl free radicals, inhibit linoleic acid peroxidation, chelate ferrous ions and reduce ferric ions were measured and compared with those of BHT and vitamins E and C. Along with this, their total phenol contents were determined. The ethyl acetate and n-butanol fractions had much higher total phenolic content (465.1 mg/g and 286.4 mg/g, respectively) when compared to the aqueous extract and their antioxidant activity in linoleic acid emulsion was higher than that of VE and similar to that of BHT. Moreover, their DPPH free radical scavenging activity was similar to that of VC and remarkably higher than that of BHT. The n-butanol fraction had hydroxyl free radical scavenging activity similar to that of VE. The ethyl acetate fraction had increased ability to reduce ferric ions compared to BHT and VC. All the samples, however, exhibited low ferrous ion-chelating activity. Theses findings collectively indicated that the ethyl acetate extract and n-butanol fractions are rich in antioxidant components and therefore has the potential to be developed as antioxidants.

Effects of bovine plasma proteins (BBP) on heat-induced gel properties of salt-soluble proteins (SSP) from pork hind leg muscles were investigated. The results showed that BBP improved functional properties of SSP gels, and when the pH value was 6.5, the optimum addition amount of BBP addition was 0.9 g/100 mL. It was also discovered that salt-soluble protein gels with added BBP and microbial transglutaminase (MTG) at respective levels of 0.9 g/100 mL and 0.125 g/100 mL had similar cooking loss, water holding capacity (WHC) and gel strength.

Objective: To prepare peanut-derived antioxidant peptides and analyze their amino acid composition and molecular weights. Methods: Defatted cold-pressed soybean cake was hydrolyzed by alcalase or flavourzyme and the hydrolysates were preliminarily separated to collect peptides having a molecular weight of less than 1 kD. The obtained peptides were further separated by sequential chromatographies on Sephadex G-25 and Sephadex G-15 columns to obtain two peptide fractions with higher hydroxyl free radical scavenging activity named as J22 (from alcalase hydrolysis) and F22 (from flavourzyme hydrolysis). The amino acid composition of the two fractions was analyzed using an amino acid analyzer. Meanwhile, Waters Acquity UPLC -LCT premier time-of-flight mass spectrometer (UPLC-TOF-MS) was used to analyze their molecular weight distribution. Results: Compared with peanut protein, Ile, Met, Tyr and His contents in the fraction J22 were increased to 13.34%, 5.18%, 45.84% from 3.75%, 0.79%, 3.44%, respectively; similarly, Ile, Met, Tyr and His contents in the fraction F22 were increased to 6.12%, 3.78%, 11.53% and 51.13% from 3.75%, 0.79%, 3.44%, respectively. Two short-chain peptides were found in each of the two fractions with respective molecular weights of 291.9 D and 391.3 D for the fraction J22 and of 205 D and 391.3 D for F22. Conclusion: J22 and F22 are both rich in tyrosine and histidine. Both fractions with small molecular weights are characteristics of fast absorption. A certain molecular weight and amino acid residues offer them with higher antioxidant activity.

The co-pigmentation effect of flavonoids on red bayberry anthocyanins was investigated by determining changes in flavonoid content and anthocyanin content, maximum absorption wavelength and color of red bayberry wine during different storage periods. Results showed that flavonoid content exhibited a trend to first crease and then decrease and reached the maximum level of 0.028 mg/mL after 91 days of storage. The change of anthocyanin content was similar with flavonoids and reached the highest level of 22.38 mg/L after 63-days storage. The maximum absorption wavelength of red bayberry anthocyanins exhibited a blue shift and a gradual decrease. The content of flavonoids revealed a positive correlation with the color parameter h, maximum absorption wavelength or anthocyanin content.

The antioxidant activities of ethyl acetate extracts (EAE) and absolute ethyl alcohol extracts (AEAE) from the fruiting bodies of Phellinus vaninii (PV), Phellinus himalayensis (PH), Phellinidium aciforum (PA), Nigroporus ussuriensis (NU) and Inonotus obliquus (IO) were evaluated by determining their scavenging rates against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radicals. The antioxidants BHT, TBHQ and Trolox were used as positive controls. The results indicated that EAEs from the fruiting bodies of the five Phellinus species significantly differed from AEAEs in their free radical scavenging rate (P ＜ 0.05). The free radical scavenging rate of AEAE from each Phellinus species was higher than that of EAE. The AEAE from PV exhibited the strongest free radical scavenging capacity with IC50 of 60.74 mg/L for DPPH free radicals and 32.26 mg/L for ABTS free radicals, respectively. However, the IC50 of BHT was 90.51 mg/L for DPPH free radicals. Therefore, the fruiting bodies of PV have stronger antioxidant capacity, and can be used in the food industry as a promising natural substitute for synthetic antioxidants.

The antioxidant activity of anthocyanins from Morus nigra L. (AMNL) in vitro was determined and compared with that of anthocyanins from Morus alba L. (AMAL) and Morus alba Linn. var. tatarica. (AMALV). The antioxidant evaluation was performed by 1,1-diphenyl-2-picryl-hydrazyl (DPPH), superoxide anion, hydroxyl and alkyl free radical scavenging assays and total antioxidant capacity (TOA) assay using rutin and VC as controls. The results showed that AMNL had stronger scavenging effect on DPPH free radicals with IC50 of 9.07 mg/L than AMAL and AMALV, but weaker scavenging effect on DPPH free radicals than rutin and vitamin C. Similarly, AMNL had more powerful scavenging effect on superoxide anion free radicals with IC50 of 2.82 mg/L and hydroxyl free radicals with IC50 of 7.77 mg/L than AMAL, AMALV, rutin and VC. However, anthocyanins from all the three cultivars of mulberry had a scavenging rate of less than 50% against alkyl free radicals. The total antioxidant capacity of AMNL revealed 11.8-, 2.6- and 1.3-fold enhancement when compared with AMAL, AMALV and rutin, but was lower than that of vitamin C.

The main objective of this study was to investigate the heat-induced changes of thermal characteristics of connective tissue collagen from beef Semitendinosus muscle. Muscle samples were heated to an internal core temperature of 40, 50, 60, 70, 80 or 90 ℃ in a water bath and in a microwave oven respectively. The changes of filter residues content and thermal characteristics of connective tissue collagen were examined with internal core temperature. The results indicated that filter residues were increased during heating, and presented significant differences (P＜0.05) at the internal core temperatures of 60, 70 ℃ and 80 ℃ between water bath and microwave heated meat samples. Internal core temperatures ranging from 40 to 60 ℃ were critical heating temperatures which affect thermal shrinkage temperatures of connective tissue collagen for both water bath and microwave heated meat samples. The significant differences in thermal shrinkage temperatures between water bath and microwave heated beef muscle samples were attributed to the heat-induced changes in thermal characteristics of connective tissue collagen.

In order to explore the relationship between chlorophyll content and color change of post-harvest broccoli during storage, a prediction model for chlorophyll content was established based on color parameter changes. Freshly harvested broccoli was stored at different temperatures (273, 278, 283, 293 K and 303 K), and the color parameter －a/b value and chlorophyll content of broccoli were determined. Kinetic models of －a/b value and chlorophyll content with respect to storage time and temperature were established on the basis of Arrhenius equation. In addition, a prediction model for chlorophyll content based on －a/b value was further developed according to the linear relationship between chlorophyll content and －a/b value. Moreover, the prediction model for chlorophyll content based on －a/b value was validated using broccoli stored at 275, 280, 285, 295 K and 305 K with a relative prediction error of 4.31%. The chlorophyll content of broccoli can be accurately predicted at the storage temperature from 273 K to 305 K using this prediction model. Therefore, the prediction model is acceptable for applying the color parameter －a/b to evaluate broccoli quality.

In this paper, particle size distribution and centrifugal sedimentation rate of water-soluble soybean polysaccharide (SSPS), sodium carboxymethyl cellulose (CMC) and high ester pectin (HMP) in milk beverage were studied. The results showed that the acidic milk beverage system exhibited an increased stability when the concentrations of SSPS, CMC and HMP were higher than 0.3%. The best stability of the acidic milk system was achieved when HMP, SSPS and CMC were added at 0.3%, 0.5% and 0.5%, respectively. Meanwhile, particle size distribution analysis and centrifugal sedimentation rate analysis could provide the consistent results for the milk beverage system. Therefore, it is feasible to use particle size distribution and centrifugal sedimentation rate for quickly and accurately analyzing the amounts of added stabilizers in milk beverage.

Yali pears were subjected to short-time high-pressure carbon dioxide (HPCD) treatment in order to explore the relationship between their CO2-induced browning and intracellular calcium. After HPCD treatment, the content of water soluble and membrane-bound calcium decreased, whereas the contents of calcium oxalate, calcium phosphate, calcium pectate and calcium carbonate increased in Yali pears as the HPCD treatment time increased. An increase in the content of carbonate calcium was also confirmed by X-ray diffraction analysis after HPCD treatment. Moreover, the structure of brown Yali pears was destroyed, which was examined by transmission electron microscope (TEM). Therefore, HPCD treatment can change the types and distribution of calcium in Yali pear cells, increase cell permeability, and accelerate the browning of fruits.

Differential scanning calorimetry (DSC) analysis was used to systematically study the effect of different concentrations of Na+, Ca2+ and H+ on the thermal denaturation temperatures of type I and type II collagens from whale sharp skin. The type I collagen had maximum absorption at 233.05 nm and the type II collagen at 232.90 nm and 277.88 nm. Aggregation dynamic analysis indicated that the turbidity of the type I and II collagens exhibited an S-shaped curve with 3 stages including initial stage, growth stage and stable stage. The thermal stability of the two types of collagens was examined by high-sensitivity differential scanning calorimetry. The thermal denaturation temperatures of the type I and II collagens were at 40 and 62 ℃, respectively. Their thermal denaturation temperatures were reduced at low concentrations of Na+ and Ca2+. These results indicated that metal ions could affect charged residues in native collagen molecules, thus leading to the reduction in thermal denaturation temperature. At intermediate concentrations of Na+ and Ca2+, the thermal denaturation temperature of type I and II collagens revealed a continuous reduction, which suggested that the loss of thermal stability might be due to the competition for water molecules between metal ions and collagen. High concentrations of Na+ and Ca2+ resulted in an increase in collagen denaturation temperature due to protein salting out. Extreme pH treatment caused partial denaturation of collagen and the denaturation peak became smaller or even disappeared.

Functional components including flavonoids, polysaccharides and polyphenols were isolated from Dicliptera chinensis, and their antioxidant activities were evaluated. The results indicated that Dicliptera chinensis was rich in flavonoids, polysaccharides and polyphenols, of which the contents were 2.4, 180.5 mg/g and 61.2 mg/g of dry Dicliptera chinensis (md), respectively. Moreover, flavonoids, polysaccharides and polyphenols from Dicliptera chinensis had strong free radical scavenging capacity, with respective scavenging rates of 76.7%, 88.2% and 35.8% against DPPH free radicals and of 90.8%, 95.7% and 80.9% against hydroxyl free radicals.

Objective: To explore the antioxidant activities of different solvent extracts from Syringa pubescens Turcz bark. Methods: ABTS+ · and DPPH free radical scavenging and ferric reducing assay were used for antioxidant activity evaluation. The content of total phenols in 75% ethanol extract and its different solvent fractions (ethyl acetate, n- butanol and petroleum ether) were determined spectrometrically. Results: All the investigated samples had strong ability to scavenge DPPH free radicals and reduce ferric ions in a dose-dependent fashion. Among them, the strongest antioxidant activity was observed in n- butanol fraction. The maximum scavenging rate of n-butanol fraction against ABTS+ · was 96.28% at the concentration of 0.62 mg/mL. However, its maximum scavenging rate of against DPPH radicals was 96.16%, which was close to that of vitamin C. The IC50 of the fraction against ABTS+ · and DPPH radicals were 0.074 mg/mL and 0.012 mg/mL, respectively. In addition, it had the strongest antioxidant activity, which might be largely associated with its high level of total phenols, 120.1μg/20 mg. Conclusion: Syringa pubescens Turcz bark has good antioxidant capacity, in which components soluble in both 75% ethanol and n-butanol reveal the strongest antioxidant capacity.

This study was focused on partial replacement of wheat flour in breads with soybean dietary fibre (SDF), corn resistant starch (RS) and their mixtures at 20% and 30% levels. The effects of high fibre levels on the thermomechanical property and baking performances of dough were investigated. The addition of SDF and RS increased dough water binding capacity and water absorption by 43.3%－63.3% and 5%－7.6%, respectively, decreased C5－C4, and inhibited the retrogradation of starch. SDF and RS had different influences on stabilization time and C1－C2 of dough. RS decreased the stabilization time by 53.52%－66.46% compared with control and increased C1－C2 by 24.14%－27.59%, while SDF played positive roles. Based on the baking performance analysis, it was found that SDF acted in synergy with RS, which not only increased dietary fibre and protein contents and improved the effects of SDF alone on bread texture and flavor, but also enhanced the moisture content of breads compared with RS alone and improved the bread yield. When bread specific volume, colour, texture and nutrition were all together concerned, the best quality of high-fibre breads could be obtained under conditions of 5% SDF-15% RS and 10% SDF-10% RS, with better mouthfeel.

Water soluble dietary fiber (S-CDF), water insoluble dietary fiber (I-CDF)(acid insoluble dietary fiber (ACI-CDF) and alkaline insoluble fiber (ALI-CDF)) were extracted from high-temperature-high-pressure-extruded corn spermoderm. Solubility and physical properties of each of these CDFs and mixtures at different ratios of S-CDF to I-CDF were analyzed before and after high-temperature-high-pressure extrusion. The results showed that extrusion at 165 ℃, a material-to-liquid ratio of 1:1.5 and a feed speed of 15 kg/h proved optimal. Under these extrusion conditions, the extraction yield of S-CDF was increased by 68.74%, the expansibility, water-holding capacity and solubility of S-CDF, I-CDF, ACI-CDF and ALI-CDF were distinctly increased. When expansibility, cation exchange capacity, water-holding capacity, oil-holding capacity and water-binding capacity were comprehensively considered, the optimal S-CDF to I-CDF ratio was 1:4.

Objectives: To separate, purify and identify sacchrides in Carica papaya flesh. Methods: Dried Carica papaya flesh was subjected to 95% ethanol extraction, petroleum ether defatting, and sequential chromatographic separation on polyamide, MCI, ODS and ODS-AQ columns. Quantitative identification was carried out by MS and NMR. Results: Four compounds Ⅰ－Ⅳ were obtained and identified as ethylα-D-fructoside(Ⅰ), ethylβ-D-fructoside(Ⅱ), benzylβ-D-glucoside(Ⅲ), and 2-O-β-D-Glu-3,6-bis(hydroxythyl)-5-phenyl-1,4-dioxan-2-ol(Ⅳ), respectively.

Variations in water loss and dry matter gain with respect to solution concentration, temperature, ultrasonic power, material thickness and ultrasonic time were investigated. Meanwhile, the interphase mass transfer of ultrasonic cavitation bubbles was analyzed. As a result, a mathematical model that describes the interphase mass transfer of ultrasonic cavitation bubbles was obtained as follows: Km≈ DABπtmRδAfφ(BI－cf2), where A was empirical constant (10-8－10-15 m2), B and C relevant liquid constants with an approximate value of 1014 and 106, respectively, f sound frequency(s-1), DAB diffusion coefficient(m2/s), tm time (s), R radius(m), δboundary layer thickness (m), φratio of number of bubbles with a radius of R to total bubbles, and I ultrasonic intensity(W/cm2). The predicted values from the model were consistent with the experimental values, indicating that the model could accurately describe the interphase mass transfer of ultrasonic cavitation bubbles.

The contents of total isothiocyanate contents and 4-methylthio-3-butenyl isothiocyanate (MTBITC) in n-hexane extracts of radish seedlings from 6 cultivars at different development stages were measured. Along with this, their antioxidant properties in vitro were evaluated using commercial FRAP, ABTS, superoxide anion free radical and hydroxyl free radical assay kits. The present study found that over 80% of total isothiocyanates in radish seedlings was MTBITC during 15 days of development. Radish seedlings aged 5－10 days revealed higher MTBITC content. At the same development stage, the seedlings of Changchun white radish, Shengfeng white radish, ivory white radish and German Giant radish contained more MTBITC than those of Fushun red radish and Mantanghong red radish. Moreover, the seedlings of Changchun white radish, Shengfeng white radish, ivory white radish and German Giant radish indicated a positive antioxidant effect-MTBITC content correlation. Despite having lower MTBITC content, Fushun red radish and Mantanghong red radish presented strong antioxidant effect.

Beef biceps femoris muscles were used to comparatively analyze differences in physcio-chemical properties and gel properties of DFD beef and normal colored beef. The results showed that DFD beef and normal colored beef significantly differed in their moisture content (P ＜0.05), but their differences in crude protein, crude fat and crude ash contents had no statistical significance (P＞0.05). There was no significant difference in their tenderness (P＞ 0.05). Furthermore, DFD beef exhibited significantly higher gel strength and water hold capacity (WHC) as compared to normal colored beef.

Different concentrations of hydrolyzed oat starch pastes with different dextrose equivalent (DE) values prepared with thermostable α-amylase were measured for their apparent viscosity and gel strength in order to find appropriate starch paste concentrations for hydrolyzed oat starch-based fat substitutes. Apparent viscosity of hydrolyzed oat starch pastes was found to decrease as the shear rate and the temperature increased, and gel strength exhibited a downward trend with increasing DE and decreasing paste concentration. Hydrolyzed oat starch pastes at concentrations ranging from 25% to 30% were more suitable to be used in fat substitutes. Moreover, 2.39%, 2.93%, 3.73% and 4.11% were identified as appropriate DE values for hydrolyzed oat starch-based fat substitutes based on gelling point, water binding capacity, oil binding capacity, freeze-thaw stability, emulsifying capacity and emulsion stability.

The present study was undertaken to investigate the effects of food gum type (using blank as control) and amount of Arabic gum addition on the volatile flavor compounds of dried duck leg meat slice, which were analyzed by HS-SPEM (headspace solid phase microextraction)-GC-MS. The results showed that Arabic gum had desired effect on the contents of aldehydes, ketones and esters in dried duck meat slice. The optimal level of Arabic gum addition was 0.05%, and 43 volatile flavor compounds were identified in the dried duck meat slice obtained, including 6 aldehydes, 8 ketones, 17 hydrocarbons, 4 alcohols, 7 heterocyclic compounds and 1 ester.

In order to evaluate the oxidative stability of olive, sunflower seed and rice bran oils, their acid, iodine and peroxide values were determined under different conditions such as air exposure, light exposure and deep-frying, and the effects of three natural antioxidants including ferulic acid, lycopene and β-carotene on rice bran oxidation were explored during deep-frying. Frying resulted in the largest increase in acid and peroxide values, followed by light exposure and air exposure. Sunflower seed oil had the largest amplitude changes in acid, iodine and peroxide values, followed by rice bran oil and olive oil. The antioxidant effectiveness of the three antioxidants investigated declined in the following sequence: ferulic acid > lycopene > β-carotene.

The reaction kinetics for the preparation of sweet potato starch phosphoric esters was investigated in this study. A kinetic model that describes sodium trimetaphosphate concentration (cA) against reaction time (t) and temperature (T) was obtained as follows: cA=c0e－1.18×1013×e－1.12×104×-×t, where c0 was initial sodium trimetaphosphate concentration. The predicted values from the model were in good agreement with the experimental values.

The pH, water loss rate, cook loss, shear force, color parameters, thiobarbituric acid reactive substances (TBARS), carnonyl content and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) pattern of carp back muscles were measured after different freeze-thaw cycles (0, 1, 3 and 5) with the aim of determining the effect of number of freeze-thaw cycles on the physicochemical characteristics of carp muscle. Results indicated that pH value showed a trend to first increase and then decrease as the number of freeze-thaw cycle increased. Water loss rate and cooking loss exhibited an upward trend and were increased by 8.77% and 20.28%, respectively, after the fifth freeze-thaw cycle (P＜0.05). Shearing force was decreased by 56.3% after one freeze-thaw cycle (P＜0.05), followed by a slow decline. Five freeze-thaw cycles could significantly increase TBARS, carnonyl content, L*value and b*value, and decrease a* values (P＜0.05). All myofibrillar protein bands in the SDS-PAGE pattern got lighter in color and even disappeared with increasing number of freeze-thaw cycles, indicating protein degradation and denaturation. Good correlations were found between lipid oxidation and either protein oxidation or color change. In summary, repeated freeze-thaw could cause protein denaturation and has a detrimental effect on the quality of carp muscle.

The present study was conducted to investigate properties of ginger starch. The results showed that the amylase content of ginger starch was 27.47% and the pasting temperature 84.98 ℃. Ginger starch paste revealed an increase in its viscosity as its concentration and pH increased. Thinning behavior and thixotropy were observed with increasing shear rate. Both solubility and swelling power of ginger starch paste exhibited a low value, which increased with increasing temperature. The transparency and sedimentation volume of ginger starch paste were 8.20% and 73%, respectively. Poor freeze-thaw stability was found for ginger starch paste and the addition of large amounts of sucrose could enhance its freeze-thaw stability.

The purpose of this work was to evaluate the availability of zinc sulfate, zinc lactate, zinc chloride, zinc acetate, zinc gluconate and zinc oxide as respective substitutes for lead oxide in preserved eggs. Changes in curing solution alkalinity, pH of whole preserved eggs and texture parameters of preserved egg white and yolk were analyzed during the curing of preserved eggs, and the maturity of preserved eggs was also observed. In general, curing solution alkalinity showed a downward trend during the curing process regardless of which of the six zinc salts was used. Further, the decrease in curing solution alkalinity was gradually attenuated as the curing proceeded, suggesting that these zinc salts can prevent penetration of egg contents. pH of whole preserved eggs presented a trend to first increase and then decrease when zinc oxide, zinc sulfate and zinc gluconate were used, and an increase-decrease-increase trend was observed for preserved eggs cured with zinc lactate or lead oxide. Moreover, the six zinc salts investigated provided preserved eggs with a much higher pH as compared to lead oxide, demonstrating that lead oxide has stronger ability to prevent sodium hydroxide from penetrating into eggs. Preserved egg white and yolk displayed different changes in their harness, adhesiveness, springiness, cohesiveness, chewiness and resilience. From the results of actual observations, it could be concluded that despite having good effectiveness, curing with lead oxide is time-consuming and that zinc lactate, zinc sulfate and zinc acetate not only result in good curing effectiveness but are time-saving as well.

Fermentation experiments in a 7 L bioreactor were carried out to study fermentation characteristics of ammonia-tolerant Rhizopus oryzae mutant ST50-2 and L-lactic acid production using aqueous ammonia as the neutralizer. Compared with its parental strain Rhizopus oryzae AS3.189, the mutant strain resulted in a reduction in fermentation period from 72 h to 56 h, in alcohol content by 22.22% and in ADH specific activity by 16.06% and an increase in L-lactic acid production by 12.30%, in LDH specific activity by 83.09% and in reducing sugar utilization rate and biomass accumulation. CaCO3 influenced mycelial pellet formation in the 7 L-scale fermentation of the mutant strain, and agitation speed and amount of aqueous ammonia addition had influence on mycelial growth, the size of mycelial pellets and L-lactic acid production, and L-lactic acid production and fermentation period were affected by pH. The optimal fermentation conditions were determined as follows: agitation speed of 400 r/min, aqueous ammonia as the neutralizer at a 15% addition and pH of smaller than 6.0 and the resulting mycelial pellet diameter, fermentation period and L-lactic acid yield were 1.0－1.5 mm, 56 h and 93.32 g/L, respectively.

A highly specific anti-Salmonella typhimurium polyclonal antibody was prepared for immunological determination of Salmonella typhimurium. Anti-Salmonella typhimurium polyclonal antibody was generated in Japanese rabbits using formalin-inactivated Salmonella typhimurium as antigen and purified by octanoic acid-ammonium sulfate precipitation and magnetic bead-antigen coupling. The titer of the prepared highly pure antibody was 3.2 × 105; however, this antibody revealed serious cross-reaction with other bacteria. In this paper, the antibody was purified by miscellaneous bacterial antigens in a reverse adsorption mode, which could eliminate the cross reaction between the antibody and miscellaneous bacteria. Therefore, an effective purification method to obtain specific polyclonal antibody was established.

According to the fact that Nisin-resistant gene and lactose-fermenting gene often have the same locus, five Nisin-resistant strains were screened from fresh milk with a selective medium (GM17) supplemented with 0.004 g/100 mL bromocresol purple and 300 IU/mL Nisin. By using skimmed culture medium, Gram s staining and microscopic examination, five strains were identified as Lactococcus lactis. PCR amplification of Nisin-resistant gene (NSR) was carried out with chromosome and plasmid DNA as templates. An expected PCR product with 400 bp was achieved from three out of five strains. The 16S rDNA sequence analysis revealed that three strains named as N1, N2 and N3 belonged to Lactococcus lactis. The full-length of Nisin-resistant determinant gene (NSR) with 1 kb in size was cloned with the plasmids N1, N2 and N3 as templates, respectively. The PCR product of N1 was sequenced and the amplicon exhibited 99% similarity with the published sequence and was therefore confirmed as NSR by Blast analysis.

The conditions for protoplast preparation and regeneration from the mycelia of Inonotus obliquus were investigated. The optimal amounts of four enzymes were explored by orthogonal array design and other conditions were studied by single factor method. The results showed that the mycelium harvesting after 7-day culture, adding 5 mg/mL cellulase, 15 mg/mL snailase, 15 mg/mL lywallzyme and 15 mg/mL drislease, using 0.6 mol/L MgSO4 as the osmotic stabilizer, digestion at 35 ℃ for 5.5 h were found to be best for the preparation of protoplasts. The optimal conditions for protoplast regeneration of Inonotus obliquus were CYM or GYM as the medium, 0.6 mol/L mannitol as the osmotic stabilizer using and digestion time of 3.5 h. No significant difference in protoplast regeneration rate was observed between CYM and GYM media. The highest protoplast regeneration rate was 0.13%.

Pickled radish was tested for dynamic changes in yeast count and species during storage at 4 ℃. The results showed that after 15-day storage, yeast count in pickled radish exhibited an obvious reduction from 4.67 × 102 to 13 CFU/g. Four yeast strains were isolated from 1-day stored samples and identified as Candida parapsilosis, Hansenula anomala, Rhodotorula acheniorum and Brettanomyces anomalus. However, only Rhodotorula acheniorum was isolated and identified in 30-day stored samples. Moreover, the amount of sugar addition had a great impact on the flavor of pickled radish during 4 ℃ storage. These findings collectively provide a useful guidance for the quality control of pickled vegetables.

In order to obtain a novel and clean preparation process for food-grade oligo-chitosan without monosaccharide, an endo-chitosanase (eCSN) that can degrade chitosan was purified from fermentation broth of Aspergillus JXSD-01 and its properties were also explored. The specific activity of the eCSN was above 50 U/mg, and its molecular mass was approximately 25 kD. The optimal reaction temperature and pH of the enzyme were 63 ℃ and 6.5, respectively. The sequence of N-terminal in the enzyme was YNLPNNLKQ. The eCSN could used for the degradation of chitosan as a natural large molecule to produce oligosaccharides with molecular weights in the range of 1000－3500 D. The obtained oligosaccharides did not contain monosaccharides and could reach the international quality standard for food-grade oligo-chitosan.

Objective: To explore the immunoactivity of Grifola frondosa fruit body polysaccharides (GFP) with different relative molecular weights. Methods: Three polysaccharide fractions from Grifola frondosa fruit body named as GFP-I (＜ 50 kD), GFP-II (50－100 kD) and GFP-III (100－200 kD) were prepared by microwave-assisted extraction followed by multi-enzyme hydrolysis and purified by ultrafiltration. The proliferation of murine lymphocytes with and without Con A or LPS induction in virto was evaluated by MTT assay. A S180 tumor-bearing mouse model was established, and the inhibitory effect of the three GFP fractions at different concentrations on tumor growth was also explored. Results: Lymphocyte proliferation rate without induction was increased by 26.558%－74.167% (P ＜ 0.001), 20.175%－152.075% (P ＜ 0.001) and 26.473%－334.797% (P ＜ 0.001), respectively in group GFP-I, GFP-II and GFP-III as compared with RPMI-1640 group, Con A-induced lymphocyte proliferation rate exhibited respective increases of 31.408%－122.894% (P ＜ 0.001), 53.075%－235.693% (P ＜ 0.001) and 83.347%－367.241% (P ＜ 0.001) for group GFP-I, GFP-II and GFP-III, and LPS-induced lymphocyte proliferation rate was increased by 20.526%－97.075% (P ＜ 0.001), 38.288%－211.348% (P ＜ 0.001) and 54.454%－344.883% (P ＜ 0.001), respectively. In comparison with NS group, the inhibitory rates of GFP-I, GFP-II and GFP-III on tumor growth in S180 tumor-bearing mice were 10.15%－22.94% (P ＜ 0.001), 12.79%－30.10% (P ＜ 0.001) and 23.86%－51.65% (P ＜ 0.001), respectively. Conclusion: GFP-I, GFP-II and GFP-III have notable immunoactivity and anti-tumor activity and the activity of GFP-III is the strongest and positively related to its concentration. Further, these three polysaccharides might mainly promote the T lymphocyte proliferation.

Immune colostrum was fermented by Bifidobacterium adolescentis and then subjected to vacuum freeze-drying to obtain freeze-dried powder. The prepared freeze-dried powder was used as the core material and CAP Opadry was used as the wall material to prepare an enteric-coated preparation with both immune and microbial activity by an air suspension microencapsulation method with the addition of protectant. The optimal protectant composition for improved viable Bifidobacterium adolescentis count was determined by single factor and orthogonal array design to be trehalose of 6%, hydrolyzed casein of 6%, and emulsifier Span80 of 3%. The viable bifidobacteria count in the obtained microcapsules was 6.0 × 108 CFU/mL and the survival rate of bifidobacteria was 18.2%, which exhibited an increase of 16.8% when compared to the control with the addition of protectant.

Bacterial flora in Scophthalmus maximus stored at 0, 3, 7 ℃ and 10 ℃ were qualitatively and quantitatively investigated. The results showed that fresh Scophthalmus maximus had a complex bacterial flora consisting of 114 strains. Of there strains, 68.4% were gram-negative bacteria and 21.1% gram-positive bacteria. The predominant bacterial flora was composed of Enterobacteria (14.9%), Pasteurella pneumotropica (13.2%), Vibrio mimicus (12.3%), Pseudomonas spp. (10.5%) and Shewanella putrefacien (8.8%). The composition of bacteria flora gradually became simple during chilled storage and the growth of Pseudomonas spp. and Shewanella putrefacien was vigorous. At the end of good quality period at 0, 3, 7 ℃ and 10 ℃, Shewanella putrefacien represented 42.2%, 39.0%, 57.1% and 56.3% (averagely 50.2%), and Pseudomonas spp. 28.0%, 23.7%, 25.5% and 31.0% (averagely 27.2%). At the end of shelf life at 0, 3, 7 ℃ and 10 ℃, Shewanella putrefacien accounted for 53.9%, 50.0%, 57.4% and 47.6% (averagely 52.3%), and Pseudomonas spp. 25.5%, 25.0%, 41.0% and 15.9% (averagely 26.5%), respectively. Therefore, it could be concluded that Shewanella putrefacien was the most predominant spoilage bacteria during storage at 0－10 ℃, followed by Pseudomonas spp..

Cellulase-free xylanase has been widely applied in the food industry as well as the paper and pulp industry. Wheat straw as one of the most important agricultural by-products can be used to induce cellulase-free xylanase production through fermentation. In the present study, the optimal conditions of wheat straw fermentation by Fusarium solani ZH0101 for producing cellulase-free xylanase were 20 g/L wheat straw, 4 g/L KH2PO4, 1 g/L CH3COONH4, 2 g/L yeast extract, initial pH of 6.0 and fermentation time of 14 days. Under the optimal fermentation conditions, the cellulase-free xylanase activity could reach up to 26.85 U/mL, which exhibited a 30% enhancement compared with the fermentation in original medium.

Objective: To screen high-affinity aptamers to Salmonella antigen by applying SELEX (system evolution of ligands by exponential enrichment) method and establish a rapid detection method for Salmonella in food. Methods: First, a single stranded DNA (ssDNA) random library with 78 nucleotides in length containing 35 random sequences was constructed. Subsequently, Eupergit C was used as the screening medium in the SELEX method. The binding of aptamers to Salmonella antigen was visualized by Biotin-Streptavidin-Anti-Digoxigenin-AP system to screen high-affinity aptamers out. Results: The binding assay demonstrated a gradual decrease in the absorbance at 405 nm as the number of screening rounds increased. High-affinity aptamers binding to Salmonella antigen were successfully obtained from the initial random ssDNA library. Conclusion: The screening process is simple and can be used for similar targets.

The optimal pH and temperature of autolysis enzymes from Antarctic krill were investigated in this paper. Meanwhile, the effects of inhibitors and metal ions on the activities of autolysis enzymes from Antarctic krill were also explored. The results showed that autolysis enzymes from Antarctic krill were mainly composed of three enzymes with respective optimal reaction pH of 3.0, 6.0 and 8.0. In addition, the optimal reaction temperatures of the three enzymes were determined to be 40, 50 ℃ and 50－60 ℃, respectively. phenylmethyl sulfonyl fluoride (PMSF) and soybean trypsin inhibitor (SBTI) exhibited an obvious inhibition effect on autolysis enzymes from Antarctic krill at a pH ranging from 3.0 to 9.0 and from 6.0 to 10.5, respectively. Moreover, Cu2+ and Ba2+ could strongly inhibit the activities of the autolysis enzymes although Ca2+ did not reveal inhibition effect. In contrast, the autolysis enzymes were activated by Mg2+.

In order to explore the technical route for prokaryotic expression and purification of bovine neutrophilβ-defensin 11 (BNBD11), BNBD11 gene was synthesized using preferred condons of E. coli, according to the reported amino acid sequence of BNBD11. The recombinant expression plasmid pET32a-BNBD11 was constructed and then transformed into E. coli BL21. The expression of BNBD11 in E. coli BL21 was induced by isopropylβ-D-1-thiogalactopyranoside (IPTG). SDS-PAGE showed that most expressed products were soluble. The fusion protein was purified by Ni Sepharose column chromatography. After the cleavage of the fusion protein by formic acid, Ni Sepharose column was used again to remove proteins with His-Tag and the purified recombinant BNBD11 was achieved. Therefore, BNBD11 was successfully expressed in E. coli, and the recombinant BNBD11 was obtained.

We isolated a strain of endophytic bacteria capable of producingα-glucosidase inhibitor from mulberry and named it S-J-X-4. On the basis of physiological and biochemical characterization and 16S rDNA gene sequence, the strain was preliminarily identified to as Bacillus atrophaeus. S-J-X-4 was cultured in LB medium andα-glucosidase inhibitor was found in the fermentation broth as an extracellular product.

In order to maximize protease activity in seed koji, the cooking of raw materials in the production of soy sauce, which was achieved by high-temperature instant cooking combined with low salt solid-state fermentation in this study, was optimized by single factor and orthogonal array design methods with respect to the effects of temperature, time and pressure. Meanwhile, amino nitrogen content in soy sauce mash at different stages of fermentation was determined. Results indicated that the optimal cooking parameters for raw materials of soy sauce were 4 min cooking at 115 ℃ and 0.15 MPa, resulting in the highest protease activity of 3545 U/g, an amino nitrogen content in original soy sauce of 1.078 g/100 mL, and a utilization rate of raw materials of 89%. In practical applications, the optimal process can not only enhance the utilization rate of raw materials and product quality and but decrease manufacturing cost and increase economic profits as well.

Response surface methodology was employed to find optimal fermentation conditions for immobilized Acetobacter pasteurianus cells obtained by using sodium alginate as the carrier. One-factor-at-a-time experiments were conducted to identify inoculum amount, initial alcohol concentration and temperature as main affecting factors of acid production. On the basis of a three-level, seventeen-run Box-Behnken experimental design, a quadratic regression model equation describing acid production as a function of the three selected variables was established. The results indicated that the optimal conditions for acetic acid fermentation were inoculum amount of 7.88 g/100 mL, initial alcohol concentration of 4.63%, and fermentation temperature of 32 ℃. Under the optimized fermentation conditions, the yield of total acids was 3.51 g/100 mL, which was close to the theoretical yield of 3.56 g/100 mL. Therefore, response surface methodology can provide the optimal fermentation condition of immobilized Acetobacter aceti for practical applications due to its reliability.

Beta-mannanase, as a kind of hemicellulose enzyme, has great economic value and social significance. With the aim of providing experimental evidence for its industrial production by fed-batch fermentation, Bacillus licheniformics HDYM-04 was cultured in a 5 L fermentor and fermentation conditions, feeding strategy and the amount of konjac powder addition were optimized. The optimal initial konjac addition, initial pH and inoculum size were determined as 60 g/L, 8.0 and 6.7%, respectively. The optimal fermentation conditions were temperature of 37 ℃, 300 r/min of agitation speed, and 3 L/min of aeration rate. Initial konjac powder addition at a level of 30 g followed by 90 g during the late logarithmic growth phase was identified as the optimal feeding strategy. As a result, the β-mannanase activity in fermentation broth was up to 3913 U/mL, which was 89% higher than before the optimizations (2070 U/mL).

In this study, 9 strains, KC1, KC2, KC5, KC6, KC7, KC15, KC16, KC17 and KC22 , were isolated and screened out from Tibetan kefir. All of the strains were identified as Streptococcus thermophilus. KC1, KC2, KC6 and KC17 were found to be capable of producing exopolysaccharides, while KC5, KC7, KC15, KC16 and KC22 had no such ability. The exopolysaccharide-producing strains presented better fermentation performance and fermented milks obtained with each of them had higher viscosity and adhesiveness when compared to the non-exopolysaccharide-producing strains, thus further demonstrating that exopolysaccharides from Streptococcus thermophilus can provide fermented milk with excellent texture.

Quantitative PCR was used to study the effect of dry heating on the Lectin gene, Cp4 epsps gene, promoter and terminator in generally modified soybeans. After 3 min of dry heating at 130 ℃, the Lectin gene was degraded to less than 407 bp. Heating at 120 ℃ for 9 min caused the Cp4 epsps gene to degrade to less than 408 bp. Dry heating had no impact on the length of the promoter, while 9 min heating at 130 ℃ caused the 125 bp fragment of the Nos terminator to degrade. Thus, this study indicated that different dry heating temperature and time have different effects on degradation of the transgenic ingredients and non-target genes components of generally modified soybean.

Neutral protease was used for enzymatic modification of succinylated soybean protein isolate (SPI). In order to achieve optimal modification conditions, functional characteristics of modified succinylated SPI were investigated with respect to process conditions including pH, temperature and enzyme dosage using response surface methodology. pH of 6.82, temperature of 48 ℃ and enzyme dosage of 6627 U/mL proved optimal. After the optimized modification, solubility, emulsifying capacity, emulsion stability, foaming ability and foam stability of succinylated SPI were increased 32.28, 3.89 4.41, 2.5 and 1.22 times, respectively.

Extraction with sodium citrate-citric acid buffer, (NH4)2SO4 fractional precipitation, DEAE-cellulose column separation and Sephadex G-150 column purification were sequentially carried out to obtain an electrophoretically pure extracellular tannase from solid state cultures of Aspergillus niger B0201, with a purification fold of 18.44. The enzyme had a molecular weight of roughly 58800 and the optimum reaction temperature and pH were 40 ℃ and 5.0, respectively. When the substrate was propyl gallate (PG), the Km was 1.08 mmol/L and the Vmax 104.1μmol/(L ·min).

Green tea powder was used as the substrate to investigate the effects of seven metal ions including Cu2+, Mn2+, Mg2+, Ca2+, Na+, Al3+ and Fe3+ on the activity of polyphenol oxidase (PPO) extracted from homogenized eggplant fruit. Cu2+, Mn2+ and Mg2+ were found to be able to promote the activity of the enzyme, while the other four metal ions had an inhibitory effect on the enzyme. The enzyme was activated by 3 mmol/L Cu2+, resulting in a total theaflavins content of 7.45 mg. Fe3+ at 5 mmol/L dramatically inhibited the enzyme and as a result, the total theaflavins content was decreased to 0.26 mg.

In our previous work, we have isolated a protease-producing Pichia kudriavzevii yeast strain. This study was undertaken to use response surface methodology to optimize fermentation conditions for protease production by the strain. Protease activity in fermentation broth was investigated with respect to C/N ratio, MgSO4 and CaCl2 concentrations, and inoculum size. A quadratic polynomial model describing the effects of the fermentation conditions on protease production was established. The highest protease production of 2504.8 U/mL was achieved under the following conditions: C/N ratio of 2, 0.5 g/L MgSO4, 0.2 g/L CaCl2, and inoculum size of 6%, which was four times higher than before optimization. In addition, the established regression model was found to have good effectiveness in predicting protease production.

In this work, litch residues left after manufacturing of litchi wine were fermented to produce ethanol and the fermentation process was optimized using response surface methodology. Ethanol production was explored with respect to pH, temperature and time. The optimal fermentation conditions were pH of 4.6 and temperature of 33 ℃ for a fermentation period of 70 h. Under these conditions, the ethanol production was up to 8.99 mL/100 g.

A novel non-chromatographic ion-exchange adsorption technique was developed to purify polyclonal antibody against Vibrio parahaemolyticus from rabbit serum using carboxylated superparamagnetic nanobeads. pH and NaCl concentration of adsorption and desorption buffers and Tween-20 concentration in washing buffer were studied, and the developed method was compared with caprylic acid-ammonium sulfate precipitation and SPA affinity chromatography. The results showed that the polyclonal antibody could be completely adsorbed by magnetic beads in 0.01 mol/L phosphate buffer (pH 6.0) and desorbed in 0.01 mol/L phosphate buffer (pH 8.0) containing 0.3 mol/L NaCl, and unadsorbed proteins were removed by washing twice with washing buffer containing 0.1% Tween-20. After the purification, the polyclonal IgG purity was 82.6%, the recovery yield 58.0%, and the titer 1/64000. In total, 10 mL of rabbit serum could be treated by 1 g of magnetic beads, and the whole process could be finished within 1 h. The method has obvious advantages compared with caprylic acid-ammonium sulfate precipitation and SPA affinity chromatography, thereby presenting a promising application prospect.

Proteases from Mucor have a good market prospect in the production of soybean polypeptides for their high effectiveness in hydrolyzing soy protein and debittering hydrolyzed soy protein. In this work, we isolated and purified two acid proteases, Pa1 and Pa2 from Actinomucor elegans AS3.2778-fermented wheat bran by ammonium sulfate fractional precipitation, CM-Sephadex cation-exchange chromatography and phenyl-Sephadex hydrophobic chromatography. Pa1 and Pa2 were identified by SDS-PAGE analysis as monomeric enzymes with respective molecular weight of 35 ku and 33 ku. Pa1 had the highest activity at pH 5.5 and 50 ℃, and Pa2 at pH 4.5 and 50 ℃. Both enzymes showed good stability at temperatures below 40 ℃ and in acidic environment (pH 4.0－7.0) and were entirely inhibited by 10μmol/L pepstatin A, indicating that they belong to the aspartic protease family. Pa1 and Pa2 were weakly inhibited by Cu2+ and Zn2+ and Mn2+, Co2+ and Cu2+, respectively. The two enzymes had the same peptide bond selectivity complementary to that of alkaline protease Pb1 from Actinomucor elegans AS3.2778. The N-terminal amino acid sequence of Pa2 was GTGTVPVTDY, which was highly homologous to that of acid proteases from Rhizopus published in the NCBI database.

Objectives: To study the effects of nitrogen and phosphorus concentrations on the growth and total lipids (TL) arachidonic acid (AA) contents of Myrmecia incise and to analyze fatty acid composition under low nitrogen and low phosphorus conditions. Methods: M. incise was grown in a glass column photobioreactor (φ 6 × 60 cm) with BG-11 medium under different concentrations of nitrogen and phosphorus (one element was fixed and the other was varied at three different levels). Lipid extraction was achieved using organic solvent extraction. GC-MS was used for fatty acid composition analysis. Results: Within the range of 300－1500 mg/L, varying NaNO3 concentration had unobvious effect on the biomass of M. incise, which was correspondingly between 2.10 g/L and 2.40 g/L. The highest TL (27% of the dry weight of M. incise) and AA contents (9.04% of the total fatty acids, and 3.16% of the dry weight of M. incise) were obtained under low nitrogen conditions. When varying from 8 to 40 mg/L, phosphorus concentration could distinctly affect the growth of M. incise, a dramatic inhibitory effect was observed under low phosphorus conditions and the resulting biomass was 0.98－2.47 g/L. TL content had little change and fluctuated around 20% when the phosphorus concentration was increased from 8 to 20 mg/L. Conclusions: TL content of M. incise was highly negatively correlated with nitrogen or phosphorus concentrations. M. incise is easier to accumulate AA under low nitrogen conditions when compared to low phosphorus.

Our previous studies have indicated the existence of Lactobacillus sakei in naturally fermented shubat. It is still unclear, however, whether the presence of Lactobacillus sakei has positive effect on the fermentation of shubat. In this work, a novel method for detecting Lactobacillus sakei was proposed based on the combination of its characteristic colony morphology and katA gene sequence and the effect of Lactobacillus sakei addition before natural fermentation on fermentation characteristics of camel milk was tested. As the fermentation proceeded, the viscosity of camel milk inoculated with Lactobacillus sakei progressively declined, while an opposite trend was observed for uninoculated camel milk. Further, the viscosity of camel milk was decreased during fermentation with 3 strains of Lactobacillus sakei isolated from home-made shubat in Xinjiang, while fermentation with other 6 lactic acid bacterial strains from the same sources resulted in an opposite trend, revealing that Lactobacillus sakei can play an important role in the fermentation of low-viscosity traditional shubat.

Objective: To explore the effect of polysaccharides from mulberry leaves (PML) on the immune function of mice. Methods: KM mice were administered with polysaccharides from mulberry leaves at the doses of 125, 250 mg/(kg ·d) and 500 mg/(kg ·d) by gavage for 30 consecutive days. The mice in blank group were administered with the same volume of saline. After the administration for 30 days, carbon clearance test, serum hemolysin determination, spleen lymphocyte transformation test and organ index (thymus and spleen) were investigated to explore the effect of PML on the immune function of mice. Results: At the investigated doses, PML could significantly improve carbon clearance capacity and spleen lymphocyte transformation capability induced by ConA. In low dose group, PML could significantly increase the thymus index. Conclusion: PML can enhance the immune function of mice.

Objective: To explore the antioxidant mechanisms of DHA in the brain of aged rats. Methods: Wistar male rats were randomly divided into four groups including 7-month-old adult group, 20-month-old aged group, and low-dose and high-dose DHA-treated 20-month-old aged groups at the respective doses of 180 mg/(kg ·d) and 360 mg/(kg ·d) (administered by gavage for 42 consecutive days). At the end of the administration period, all rats were sacrificed and the activities of superoxide dismutase (SOD), gtutathione peroxidase (GSH-Px) and catalase (CAT) and the level of malondialdehyde (MDA) were assayed in brain. In addition, the fatty acid profile in brain was analyzed by gas chromatography-mass spectrometry, and the phospholipid composition was also analyzed by thin layer chromatography and phosphomolybdate methods. Results: Compared with the aged group, the activities of SOD, GSH-Px and CAT in the brain of the DHA-treated groups were significantly increased and MDA content was significantly decreased. Fatty acid analysis showed that DHA-treated rats exhibited an obvious increase in the ratio of total n-3 fatty acids to total n-6 fatty acids and the ratio of DHA to arachidonic acid (AA) and an obvious reduction in AA level. It was also revealed that DHA could improve the levels of phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine and sphingomgelins in the brain of rats. Conclusion: DHA can obviously improve antioxidant capacity in aged rats and its antioxidant mechanism may be due to DHA-induced change of fatty acid profile in the brain.

Objective: To explore the effect and mechanism of resveratrol on the body weight and adipose tissue distribution of KKAy mice. Methods: Totally 36 8-week-old KKAy mice were randomly divided into 3 groups, and fed a standard AIN93G diet or a standard AIN93G diet supplemented with resveratrol at the dose of 2 or 4 g/kg. A total of 12 C57BL/6J mice fed the standard diet were chosen as the control. The body weight, subcutaneous fat and epididymal fat of the mice were measured. The expression of silent information regulator (sirt-1), peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα) in the adipose tissue of rats were evaluated by Western blot. Results: Resveratrol could reduce the body weight of KKAy mice without dependence on food intake. Body weight and adipose tissue weight was much lower mice in the high-dose group when compared with the model group. In addition, resveratrol also enhanced the expression level of sirt-1 and inhibited the expression of PPARγ and C/EBPα in the adipose tissue of mice. Conclusion: Resveratol can ameliorate body adiposity in mice due to its promoting effect on the expression of sirt-1 in the adipose tissue and suppressive function on the expression of proteins related to lipogenesis and adipocyte differentiation.

Objective: To explore the improving effect of dietary fiber from Malusasiatica pomace on the defecation of mice and provide the basis for the development of dietary fibers. Methods: Kunming mice were randomly divided into 5 groups including blank control group, constipation model group and DF groups at the low, middle and high doses. The effect of dietary fiber from Malusasiatica pomace on defecation function was evaluated by ink-pushing rate in small intestine, first defecation time, first black feces time and feces weight in mice with diphenoxylate-induced constipation. Results: After mice were subjected to continuous intragastric infusion for 14 days, ink-pushing rate was increased in the small intestine of mice administered with DF at low, middle and high doses as compared to the constipation model group, which exhibited an extremely significant difference between the middle or high dose groups and the constipation model group (P ＜ 0.01); however, no significant difference was observed between the low-dose group and the constipation model group (P ＜ 0.05). The first defecation time in low and middle dose groups was shorter than that in the constipation model group (P ＜ 0.05); however, the first defecation time in high dose group revealed a significant decrease when compared with that in the constipation model group (P ＜ 0.01). Compared with the model group, the first black feces time in each DF treatment group was shortened (P ＜ 0.01). The feces weight during 12 hours in the middle dose group was higher than that of the constipation model group (P ＜ 0.05); however, the feces weight in high dose group revealed an obvious increase when compared with the constipation model group (P ＜ 0.01). Conclusion: Dietary fiber from Malusasiatica pomace plays a favorable role in improving defecation and intestinal peristalsis.

The nutritional composition in the muscle of Penaeus japonicus was analyzed and compared with that of some high-quality shrimps, crabs and fish. The results showed that the contents of flesh, water, crude ash, crude protein and fat in P. japonicus were 39.21%, 77.16%, 1.79%, 17.74% and 2.08%, respectively. Eighteen common amino acids were detected in the muscle of P. japonicus. In dry samples, the content of total amino acids (TAA) was 70.68%, in which the content of essential amino acids (EAA) was 23.25%. The essential amino acids index (EAAI) was 70.72, which was lower than egg protein standard but higher than WHO/FAO standard. According to amino acid scores (AAS) and chemical scores (CS), the first limited amino acid was Trp and the second limited amino acid Val. The content of five delicious amino acids (DAA) were 35.71% in dry samples. Meanwhile, nine saturated fatty acids (SFA), eight mono-unsaturated fatty acids (MUFA) and eight polyunsaturated fatty acids (PUFA) were also detected in the muscle of P. japonicus. The PUFAs in the muscle of P. japonicus accounted for 64.04% of total fatty acids. The contents of EPA and DHA were 1.70% and 10.92% of total fatty acids, respectively, and the contents of PUFA, EPA and DHA were higher than those in some shrimps and freshwater fish. The mineral elements Zn and Fe were abundant, and the contents of harmful elements such as Cd, Cr and Ni were low. Therefore, it is easy to conclude that Penaeus japonicus is a nutritious and delicious food.

Objective: To explore the repairing effect of water-soluble polysaccharide from corn (WSPC) on islet immune damage in diabetic rats. Methods: Streptozotocin (STZ) was used to establish diabetic rat models via intraperitoneal injection. The successfully established models were randomly divided into three groups administered with WSPC at low, middle and high doses, as well as the model control group. WSPC administration was carried out by gavage for 28 consecutive days. The changes in blood sugar index, INS, HOMA-IS, and the contents of GAD-Ab, ICA and IAA in the diabetic rats were determined. Results: Compared with the model control group, blood glucose levels in treatment groups administered with WSPC at the low, middle and high doses were significantly decreased in a dose-dependent manner (P ＜ 0.05). Meanwhile, INS was increased with increasing WSPC dose and revealed a significant difference between the three treatment groups and the model control group (P ＜0.05). Compared with the normal control group, HOMA-IS in each WSPC group had a significant difference; however, no obvious difference in each WSPC was observed. In addition, compared with the model control group, GAD-Ab and IAA in the high-dose group did not exhibit an obvious difference; in contrast, ICA revealed a significant difference betweeb the middle-dose and high-dose groups. Conclusion: WSPC can promote insulin secretion in pancreatic islet β cells through rehabilitation of autoimmune injury and significantly increase serum insulin level (P ＜0.05), thereby playing an important role in reducing blood glucose level.

Objective: To explore the effect of NattozimesTM on carrageenan-induced tail thrombosis in rats. Methods: Male rats were randomly divided into five groups including model control group, aspirin group, low-dose NattozimesTM group, middle-dose NattozimesTM group and high-dose NattozimesTM group. On the 28th days of the intragastric administration period of 30 days, tail thrombosis model was established by subcutaneous injection carrageenan into the hind foot pad. The length of dark tails at different time points was observed. Meanwhile, PT, APTT, TT, Fb, INR, t-PA and PAI in vein blood were determined. Results: At 24 and 48 hours after tail thrombosis model creation, black tails in the low- and middle-dose NattozimesTM groups were longer than those in the model control group, but no obvious difference in each group was observed at 60 hours. Compared with the model control group, PT and INR in the low- and middle-dose NattozimesTM groups were prolonged, APTT was considerably shortened and t-PA was higher in each dose group, and the high-dose NattozimesTM group exhibited a distinctly shorter TT and a notably increased Fb, and the low- and high-dose groups showed a decrease in PAI. Conclusion: Eating NattozimesTM can prevent the formation of carrageenan-induced tail thrombosis in rats.

Purpose: To explore the protective effect of green tea polyphenols on chronic alcoholic hepatic injury in mice. Methods: Liver injury was induced in mice by 56° Beijing Red Star Erguotou wine at gradually increasing dose. The mouse model with liver injury was intervened by green tea polyphenols for 10 weeks followed by determination of body weight and liver index. Meanwhile, the contents of glutathione (GSH), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), xanthine oxidase (XOD) and Na+-K+-ATPase in the liver, and serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were also determined. Hepatic pathological changes were examined. Results: The model group displayed a significant reduction in body weight, hepatic GSH content and hepatic SOD, GSH-Px and Na+-K+-ATPase activities when compared with the control group (P ＜ 0.05), while a significant increase in liver index, hepatic MDA content, hepatic XOD activity and serum ALT and AST activities was observed for the model group (P ＜ 0.05), and the fat degeneration in liver and pathological inflammation revealed an obvious change. Compared with the model group, green tea polyphenol-treated rats indicated a decrease in liver index (P ＜ 0.05), an increase in hepatic SOD and GSH-Px activities, the high- and medium-dose groups revealed higher body weight and hepatic Na+-K+-ATPase activity and lower serum ALT and AST activities and hepatic XOD activity (P ＜ 0.05), a significant decrease in hepatic MDA content and an increase in hepatic GSH content were observed for the high-dose group. Furthermore, hepatic pathological changes were attenuated or even reversed. Conclusion: Green tea polyphenols can protect liver from chronic alcoholic damage to some extent, and the mechanism may be related to its antioxidant effect.

In order to explore the nutritional effect of egg yolk lecithin on the brain of mice, egg yolk was extracted by sequential organic solvent extraction and purified by silica column chromatography to obtain lecithin with purity of 95.67%. Mice were administered intragastrically with purified lecithin for 30 days and then subjected to Morris water maze test and step-down test. The results showed that the escaping time of experimental mice was shorten significantly (P ＜ 0.05) in the Morris water maze test, and the latency period was extended in the step-down test (P ＜ 0.05) as well as the number of errors was decreased significantly (P ＜ 0.05). These investigations suggested that egg yolk lecithin could improve memory function and promote brain development of mice.

In order to explore the effect of Lycium barbarum polysaccharides (LBP) on intestinal mucosal barrier function in rats, the number and distribution of intraepithelial lymphocytes (IEL) and goblet cells (GC) in 10 C57BL/J mice were observed by light microscope after oral administration with LBP for a week. The results showed that the number of IEL and GC exhibited an obvious increase and these cells moved towards the inner layer of the small intestine. Meanwhile, the IL-2 expression level in the intestinal mucosa also revealed a significant increase. These studies suggested that LBP could promote the integrity of the small intestinal mucosal barrier structure and improve the immune function.

Aim: To investigate the protective effect of lactosucrose (LS) on the plasma antioxidant system in TNBS-induced colitis rats. Methods: A total of 32 female SD rats were randomly divided into 4 groups: normal control group, model group, LS group and SASP (sulfasalazine) group. The other 3 groups received TNBS induction except the normal control group and were orally administrated with normal saline (10 mL/(kg ·d)), LS (250 mg/(kg ·d)) or SASP (250 mg/(kg ·d)) once daily for 3 successive weeks. At the end of the administration period, all rats were scarified for determination of colon mucosadamage index (CMDI), the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), inducible nitric oxide synthase (iNOS) and myeloperoxidase (MPO) and malondialdehyde (MDA) level. Results: Compared with the model group, the activities of SOD and GSH-Px in the LS group were increased significantly and could resume their normal levels. The LS group exhibited significantly higher GSH-Px activity when compared with the SASP group and significantly lower CMDI and MPO and iNOS activities when compared with the model group, especially that MPO could be restored to its normal level. Conclusion: LS is capable of improving antioxidant function in the plasma of colitis rats and decreasing the activity of iNOS and inflammatory cell immersion.

Objective: To investigate the effect of Pleurotus citrinopileatus polysaccharides (PCP) on antioxidant enzyme activities and isozyme profiles in the liver, heart and kidney of mice with carbon tetrachloride-induced acute liver injury. Methods:Mice were randomly divided into 6 groups: control group, model group, drug group (bifendate pills, 150 mg/(kg ·d)), low-dose PCP group (100 mg/(kg ·d)), medium-dose PCP group (200 mg/(kg ·d)) and high-dose PCP group (400 mg/(kg ·d)). All mice were administered for 30 consecutive days, and were fasted for 16 h after the end of the administration period before oral administration of CCl4 dispersed in salad oil for creating CCl4-inducedacute liver injury model. At 24 h postadministration, all mice were sacrificed to assay the activities of ALT, AST and antioxidant enzymes in the blood, liver, heart and kidney and analyze the isozyme profiles of CAT and SOD by gradientpolyacrylamide gel electrophoresis. Results: Compared with the control group, the model group exhibited a significant increase in the activities of serum ALT and AST and a significant decrease in the activities of the investigated antioxidant enzymes in the liver, heart and kidney of mice (P＜ 0.05 or 0.01 ). PCP administration resulted in a significant decrease in the activities of serum ALT and AST, and the medium-dose and high-dose PCP group exhibited significantly increased activities of CAT, GSH-Px and MnSOD in the liver, heart and kidney and could resume their normal levels. One CAT band was detected in the liver, heart and kidney and CCl4-induced acute liver injury resulted in a significant decrease in its staining intensity. In contrast, the staining intensity of the band was restored to the normal level after PCP administration. Similarly, One MnSOD and three CuZnSOD were detected in the liver and kidney, and PCP administration resulted in an increase in the staining intensity of total SOD and MnSOD, one MnSOD and two CuZnSOD were detected in the heart and the staining intensity of the bands were increased to their normal levels after PCP administration. Conclusions: PCP can significantly decrease the levels of serum ALT and AST, enhance the activities of antioxidant enzymes in the liver, heart and kidney of mice and promote the expression of their isozymes, indicating that PCP protects the major visceral organs of mice against carbon tetrachloride-induced acute liver injury.

Purpose: To evaluate the effects of tea seed oil on reducing blood lipid and preventing fatty liver in rats. Methods: SD rats were fed for 4 days and then randomly assigned into six groups of 10 rats each: high fat control group (A), blank control group (B), high-dose tea seed oil group (C), medium-dose tea seed oil group (D), low-dose tea seed oil group (E) and olive oil control group (F). The daily food intake per kilogram of body weight of group A was 150 g high fat diet + 9.0 g normal saline, of group B 150 g basal diet + 9.0 g normal saline, of group C 150 g high fat diet + 9.0 g tea seed oil, of group D 150 g high fat diet + 3.0 g tea seed oil, of group E 150 g high fat diet + 1.5 g tea seed oil, and of group F 150 g high fat diet + 9.0 g olive oil. High fat models were established by feeding high fat diet. After feeding for 7 consecutive weeks, all rats were killed to determine the levels of serum TG, TC and HDL-C and to observe pathological changes in the liver. Results: Serum TG and TC levels were significantly decreased in tea seed oil-treated rats compared with the high fat control group (P ＜ 0.01), and slighter pathological changes were observed in the liver of tea seed oil-treated rats (P ＜ 0.05). Moreover, the high-dose tea seed oil group and the olive oil control group had similar pathological changes, with 90% normal or light degree fatty liver and 10% middle degree fatty live, which all exhibited manifestations similar to those of the blank control group. Conclusion: Tea seed oil has blood lipid-lowering and fatty liver-preventing effects.

In this article, the current status of heavy metal contamination in shellfish is reported. The commonly-used methods for the detection and removal of heavy metals are summarized, mainly including atomic absorption spectrometry (AAS), atomic fluorescence spectrometry (AFS), inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectrometry (ICP-AES) and anodic stripping voltammetry (ASV). The major methods for removing heavy metals are supercritical fluid extraction, ultrasound-assisted extraction and heavy metal toxicity degradation.

It is necessary to develop identification technologies for tea varieties and geographic origins due to increased adulteration in tea products. In this paper, we review the applications of high performance liquid chromatography fingerprint, near infrared spectroscopy, multi-spectral image texture technology, fluorescence spectroscopy and trace element analysis for the identification of tea varieties and origins. Meanwhile, their future development trends are also proposed.

Heterocyclic amines (HAs) are mutagenic and carcinogenic compounds formed in high-protein foods such as meat and fish during cooking. Current sample pretreatment technologies and detection methods for HAs in cooked meats are summarized, and the stress is put on introducing approaches for controlling their formation in the processing of meat products.

Enterobacter sakazakii (Cronobacter spp.) is an emerging food-borne conditional pathogen associated with meningitis, bacteremia and necrotizing enterocolitis; especially neonatal meningitis is of high potential danger in neonates. Many bio-molecular assays like regular PCR, real-Time PCR, loop-mediated isothermal amplification, and molecular probes are highly sensitive for detecting specific food-borne pathogens, and they have overcome the disadvantages of being time-consuming, tedious operation and ambiguous results, which are usually associated with conventional detection methods.

Anthocyanins, possessing various bioactivities such as anti-oxidation, are a class of natural water-soluble phenolic pigments derived from plants. Anthocyanins are excellent functional food colorants but prone to degrade when exposed to environmental factors such as light, heat and reactive oxygen species (ROS) during food processing and storage. As a result, poor stability mainly restrains its applications. Based on the literature review, we summarize the degradation kinetics of anthocyanins and degradation mechanisms under the influence of various factors (light, heat, oxidation and intestinal microbial flora). Meanwhile, directions for future research of anthocyanins degradation are proposed in order to provide beneficial supports for the stabilization of anthocyanins in foods.

Several lactic acid bacteria (LAB) produce peptides with antimicrobial activity usually referred to as bacteriocins. Bacteriocins are diverse in terms of structure, mode of action, antimicrobial spectrum, and potency. Both LAB and their bacteriocins are generally regarded as safe. Bacteriocins produced by LABs have demonstrated great potential as natural preservatives Intercellular communication has emerged as the key regulatory mechanism that controls the synthesis of bacteriocins via a regulatory strategy denominated quorum sensing, which allows population-wide synchronised production of antimicrobial peptides as a function of cell density. The intercellular communication phenomenon required for sensing of the cell density is mediated by secreted signaling molecules that accumulate in the environment as the cell density increase and activate signal transduction cascades, resulting in the production of bacteriocins. This review aims at describing the types of signal molecules, signal transduction mechanism and the regulation of quorum sensing in bacteriocins synthesis of LAB and understanding the regulation mechanism of quorum sensing involved in the production of two classes of bacteriocin in LAB.

Several preservatives commonly used for Penaeus vannamei are briefly introduced in this paper, and the recent research of biological preservatives such as bacteriolysis enzyme, nisin, phytic acid and chitosan is elaborated in detail. The biological preservatives may obtain more advantages for further development in P. vannamei preservation due to their safety and high-efficiency.

Bovine lactoferricin (LfcinB) is a 25-residue peptide with highly effective, broad-spectrum antimicrobial generated by pepsin digestion of bovine lactoferin. LfcinB has revealed huge potential in the medicinal, food additive, and feed industries as a new type of antimicrobial peptide. This review presents its important structural features, physicochemical properties, biological function, mechanism of action and future prospects in detail. In addition, the recent advances in the research on its derivatives are also summarized.

Resveratrol is a natural phytoalexin, which is generated in plants due to fungal infections, ultraviolet illumination or pathological conditions. The phytoalexin enhances the resistance of plants against pathogens and has considerable physiological activities such as antioxidant, antimicrobial, blood lipid-regulating and anticancer functions. It has been shown to be able to prolong the lives of animals. Great advances have been made in the research on the synthesis pathway in grape and related enzymes. With the development of bioengineering technology, it is no longer difficult to express resveratrol synthase gene and synthesize resveratrol in plants, microbes and animals. This article reviews recent studies on the synthesis of resveratrol in different organisms. Meanwhile, problems and future directions for research into the synthesis of resveratrol by bioengineering technology are proposed.