A type-J coil planet centrifuge with a 7.0 cm revolution radius was designed through the tandem connection of two spiral tubes. The β value was in the range of 0.3－0.7. The total column capacity was 30 mL. Different polarity solvent systems such as n-heptane:methanol, n-hexane:ethyl acetate:methanol:water, n-butanol:acetic acid:water and PEG 1000:K2HPO4:water were used to comparatively study the retention capacities of the new HSCCC and the traditional multilayer coil HSCCC. The stationary phase retention factor (Sf) of the traditional multilayer coil HSCCC was 50% in n-heptane:methanol system and 60% in n-hexane:ethyl acetate:methanol:water system at a flow rate of 1 mL/min under the L-I-T elution mode, while for the spiral tube HSCCC, the Sf values were 60% and 68%, respectively. The Sf values of the traditional multilayer coil HSCCC and the spiral tube HSCCC were 22% and 60% in n-butanol:acetic acid:water system at a flow rate of 0.5 mL/min under the U-O-H elution mode and 15% and 46% in PEG 1000:K2HPO4:water system at the same flow rate under the L-I-T elution mode, respectively. An excellent linear relationship between Sf and (1/g-levels)1/2 was achieved using each investigated solvent system. The new HSCCC was applied to separate anthocyanins from Lycium ruthenicum Murr. using a highly polar system composed of methyl tert-butyl ether, n-butanol, acetonitrile, water and trifluoroacetic acid (2.5:1.5:1:5:0.001), and the results showed that anthocyanins with a purity of 89% were obtained at a flow rate of 1 mL/min.

In order to improve the processing characteristics and eating quality of corn and develop a new approach for the application of microbial enzymes in the food industry, corn flour was modified by enzymes from Bacillus subtilis or Aspergillus niger. The results indicated that the contents of starch and protein in corn flour decreased significantly after both enzymatic treatments, while amylose content and solubility increased. The water-holding capacity, swelling power and viscosity of corn flour were increased after treatment with crude extracellular enzyme from Aspergillus niger but decreased after treatment with crude extracellular enzyme from Aspergillus niger. Both enzymatic treatments could result in a considerable increase in the extensibility and resistance of corn flour dough, thereby having the potential for applications in noodles, dumplings and other staple foods. In conclusion, enzymatic modification can be used to improve the processing characteristics and eating quality of corn flour.

The antibacterial activities of food preservatives including potassium sorbate, sodium diacetate, capryl monoglyceride, disodium ethylene-diamine-tetraacetate (EDTA), nisin, chitosan and ε-polylysine (ε-PL) against 12 meat spoilage strains such as 2 Bacillus circulans strains, 3 Bacillus subtilis strains, 3 Bacillus licheniformis strains, 2 Bacillus coagulans strains, 1 Hafnia alvei strain and an Enterococcus strain were investigated based on inhibitory rate and minimum inhibitory concentration. The results showed that seven food preservatives had inhibitory effect on all tested bacteria at different levels. They could be ranked in decreasing order of antibacterial activity as follows: nisin＞chitosan ＞ε-PL＞capryl monoglyceride＞EDTA ＞sodium diacetate＞potassium sorbate. Three bio-preservatives including nisin, chitosan and ε-PL had better antibacterial activity than other four chemical preservatives. In addition, the antibacterial activity of 7 preservatives exhibited great differences among species and among different strains from the same species.

In order to explore the effect of ultra-high pressure (UHP) treatment on the quality of kiwi juice, fresh kiwi juice was treated with ultra-high pressure at a pressure level between 200 MPa and 500 MPa. The results showed that the changes in soluble solids, total acid, pH and other quality parameters of kiwi juice were not obvious with increasing pressure. However, the contents of vitamin C and chlorophyll revealed a slight decrease. After UHP treatment, acids and aldehydes (belonging to aroma components) revealed an increase trend, while esters and alcohols exhibited a decrease trend. The losses of vitamin C and chlorophyll in UHP-treated kiwi juice after 28 d of storage at 4 ℃ were 21.8% and 40.5%, respectively, indicating a trend towards deterioration. The losses of vitamin C and chlorophyll after 120 d of storage at －18 ℃ were 14.6% and 20.8%, respectively. Therefore, the nutrients of kiwi juice can be better maintained during storage at －18 ℃.

The inhibitory and synergistic inhibitory effects of volatile aromatic components from tea tree oil, eugenol and citral on rot-causing fungi such as Aspergillus niger in litchi were studied. The results showed that the volatile aromatic components from eugenol and citral had strong inhibitory effect on Aspergillus niger with minimum inhibition concentrations of 0.3μL/cm3 (air volume) and 0.4 μL/cm3 (air volume), respectively. The anti-fungal effect of tea tree oil was weak, while its inhibitory effect could be enhanced in the attendance of eugenol and citral.

In this study, the antioxidant activity of the fermentation supernatants and intracellular extracts of four species of lactic acid bacteria including Lactobacillus fermentium, Lactococcus lactis, Lactobacillus acidophilus and Lactobacillus helveticus was comparatively studied by anti-lipid peroxidation assay, reducing power assay, and DPPH and superoxide anion and hydroxyl free radical scavenging assays. The results indicated that different lactic acid bacteria had different antioxidant activity. Lactobacillus helveticus had higher hydroxyl radical scavenging activity, DPPH radical scavenging activity and reducing power, while Lactococcus lactis and Lactobacillus acidophilus had notable superoxide anion radical scavenging activity. In addition, Lactobacillus fermentium had the highest lipid peroxidation-inhibitory activity. Further, the antioxidant mechanism of lactic acid bacteria may be related to the presence of SOD and GSH-Px activities.

In order to explore the effect of inorganic salts on papain-induced coagulation of soybean protein, the changes of clotting time, texture properties, pH and protein degradation were determined during or after the coagulation of soybean protein isolate (SPI) in the presence of one of five salts including NaCl, KCl, CaCl2, MgCl2 and MgSO4. The results showed that the clotting time was shortened and gel strength was increased; the pH of SPI was reduced after the addition of salts. After papain was added, the pH revealed a continuous decrease to a steady level upon a certain time of incubation. Ca2+ and Mg2+ revealed more effective than Na+ and K+ on both clotting time and gel strength under the same ionic strength. The gel strength revealed an increase by 60% when the amount of papain was reduced to 0.1% from 0.15% (m/m). Therefore, the presence of salts could shorten clotting time and gel strength, and the addition of calcium or magnesium salts is an effective way to enhance the strength of papain-induced SPI gel.

A texture analyzer was used to test the gel strength, gumminess, chewiness, adhesiveness, springiness and cohesiveness of tea polysaccharides (TPs) under varying conditions of concentration, heating temperature, time, pH and calcium ion concentration. The results showed that the TPs concentration and heating temperature required for gelation were at least 5 mg/mL and 50 ℃, respectively. TPs gel strength was directly proportional to TPs concentration and temperature. Long storage time and strong acidity or alkaline could reduce the gel strength of TPs while calcium ion did not reveal stimulation effect on it.

In order to explore the effect of ultra high pressure (UHP) treatment on aroma components of strawberry juice, fresh strawberry juice was subjected to UHP treatment under different pressure levels. The volatile aromatic compounds of strawberry juice were isolated by solid-phase microextraction (SPME) and analyzed by capillary gas chromatography-mass spectrometry (GC-MS). The relative contents of aroma components were determined by area normalization method. The results showed that UHP treatment caused great changes to aroma components of strawberry juice. The predominant aroma compounds including butyric acid methyl ester, caproic acid methyl ester, caproic acid ethyl ester and 2,5-2 methyl-4-hydroxyl-3(2H)-furan ketone were increased most obviously. Thus, UHP treatment is effective in enhancing the characteristic aroma of strawberry juice. Collectively, our findings indicate that the kinds and amounts of predominant aromatic components in strawberry juice can be effectively retained or even increased during 25 min of UHP treatment at 300 MPa. In conclusion, UHP treatment holds promise as a cold processing technique for strawberry juice.

In order to examine the effect of fat and oil on rheological properties and microstructure of wheat flour dough, wheat four with added palm stearin was used to prepare wheat flour dough. It was found that palm stearin could increase dough formation time, stability time and stretch resistance, improve dough rheological properties and wheat flour quality. The microscopic structure of wheat flour dough with added palm stearin showed even more prtoein granules and more smooth surface of strach granules. Collectively, farinograph and tensile tests demonstrated that the optimal content of palm stearin in wheat flour was 6%.

Lowry method, ANS fluorescence probe, circular dichroism and fluorescent spectroscopy were applied to explore the solubility, surface hydrophobicity, secondary structure and tertiary structure of soybean protein isolate at different pH conditions. The results showed that the transformation from β-sheet structure to α-helix structure, and the microenvironment polarity of Trp residues revealed an obvious increase with increasing pH. A negatively linear correlation between the surface hydrophobicity and solubility of soybean protein isolate was observed. Meanwhile, the surface hydrophobicity of soybean protein isolate was negatively correlated with the amount of α-helix structure.

Using scanning electron microscope and X-ray diffraction, the granular morphology and crystal characteristics of fried naked oat starch were examined. At the same time, physicochemical properties and digestibility were also investigated. Compared with non-fried naked oat starch, the appearance and crystal characteristics of fried naked oat starch changed greatly; meanwhile, its amylose content, blue value, gelatinization temperature and swelling degree revealed an obvious decrease and the contents of SDS and RS were lower, whereas fried naked oat starch exhibited a significant increase in the transparence and solubility as well as higher RDS content. Furthermore, both the water separation rates of non-fried and fried naked oat starches were higher than 50%.

Objective: to isaolate, purify and structurally characterize a water-soluble polysaccharide from the whole herbs of Ligularia hodgsonii. Methods: crude polysaccharide named as LW was extracted from Ligularia hodgsonii. A ploysaccharide fraction named as LW21 was obtained after acidic ethanol fractionation and DEAE-Sephadex A-25 gel filtration. The purity of LW21 was identified by paper chromatography, Sepharose CL-4B chromatography and cellulous acetate electrophoresis, and its structure was analyzed by HIO4 oxidation, Smith degradation, methylation, IR, NMR, GC and GC-MS. Results: LW21 was a homogenous polysaccharide. LW21 was composed of rhamose (Rha), arabinose (Ara), mannose (Man), glucose (Glc) and galactose (Gal) with a molar ratio of 7.4: 11.9: 25.7: 40.0: 14.9. Its average molecular weight was 110 kD. Its main chain was made up of β-(1→2)-linked or β-(1→6)-linked Man, and β-(1→2)-linked orβ-(1→6)-linked Glc residues. The β-(1→2)-linked Man was substituted at 2－O and 4－O; β-(1→6)-linked Man was substituted at 3－O and 6－O; and β-(1→2)-linked Glc was substituted at 6－O; β-(1→6)-linked Gal was substituted at 2－O. The side chain was composed of Rha, Ara and Gal. The non-reduced end was composed of Gal, Ara, Rha and Glc. Conclusion: LW21 is a new polysaccharide isolated from Ligularia hodgsonii for the first time.

In order to eliminate Chinese consumers,misunderstanding of vermicelli as a traditional food, a comparative analysis on resistant starch contents between vermicelli and daily foods was conducted. The results showed that the contents of resistant starch in hot rice, cool steamed bread, cookies, instant noodles, sweet potato vermicelli and mung bean vermicelli were 0.27%, 1.99%, 1.16%, 1.64%, 3.69% and 6.21%, respectively. The content of resistant starch in vermicelli was obviously higher than that in ordinary foods.

Chicken bone hydrolysate was used to prepare chicken flavor matrix via Maillard reaction in this work. The molecular weight of melanoidin in the prepared flavor matrix was determined to be approximately 11561.1 D by size-exclusion high-performance liquid chromatography(HPSEC). The FT-IR results revealed that melanoidin fractions separated by 0.2 mol/L and 0.5 mol/L NaCl solutions had characteristic absorption peaks of C-H, C＝O and C-N, suggesting that melanoidin in chicken flavor matrix was organic compound formed by polymerization and cross-linking of amino acid mixtures and degraded products in an early stage of Maillard reaction. The structure of melanoidin needs to be further investigated.

In this study, the inhibitory activity against bacteria and fungi of sterol extracts from Begonia sinensis rhizome was investigated by Oxford cup assay and growth rate assay, respectively. The results showed that sterol extracts had strong inhibition on Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Salmonella spp., Shigella spp., Aspergillus niger and Penicillium digitatum. Among these microorganisms, sterol extracts showed the strongest inhibition against Staphylococcus aureus with an inhibition diameters larger than 9 mm and an MIC of 0.5 mg/mL. It was also found that the inhibition of microorganism by sterol extracts was positivley correlated with their concentration but negatively correlated with culture time.

The physico-chemical properties of sika deer antler collagen extracted in acidic solution with pepsin were determined using ultraviolet (UV) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, amino acid analyzer, SDS-PAGE and differential scanning calorimetry (DSC). A typical absorption peak at 230 nm was found in the UV spectrum. The FTIR spectrum showed that the amide A, B and Ⅰ spectral bands were consistent with those standard typeⅠ collagen with three-spiral structure. SDS-PAGE results indicated that sika deer antler collagen was composed of one β-chain and two different α-chains (α1 and α2), which were the characteristics of type Ⅰ collagen. Amino acid composition analysis revealed the characteristic amino acids of typeⅠ collagen. The ts was 84.05 ℃. On the basis of the analysis above, it could be concluded that sika deer antler collagen had typical physico-chemical properties of type Ⅰ collagen.

In this study, ultrasonic-assisted extraction was used to extract bioactive components from peanut shells with water, 60% ethanol or 60% ethanol combined with cellulase. The scavenging capacities of peanut shell extracts on DPPH and hydroxyl free radicals were evaluated. The contents of total phenol were determined. The results showed that the contents of total phenol in the extracts obtained using water, 60% ethanol and 60% ethanol + cellulase were 81.22, 205.9 mg/100 g and 370.8 mg/100 g, respectively. All three extracts had strong antioxidant capacity, especially the one obtained using 60% ethanol + cellulase. The scavenging rates of this extract on DPPH and hydroxyl free radicals were 88.49% and 93.65%, respectively. Therefore, the antioxidant capacity is positively correlated with the contents of total phenol in peanut shell extracts.

In this study, exoplysaccharides were isolated from Cordyceps sinensis. Gel permeation chromatography (GPC) was used to determine molecular weight (MW) and molecular weight distribution of exopolysaccharides subjected to acid hydrolysis. The results showed that high molecular weight fraction (HMWF) and low molecular weight fraction (LMWF) of exopolysaccharides were obtained by acid hydrolysis. The content, MW and polydispersity index (PDI) of HMWF decreased with increasing reaction time, but the molecular weight degradation ratio (MWDR) showed a linear increase. On the other hand, the content of LMWF increased with increasing reaction time, with mostly a molecular weight of 3.0 kD. The MWDR of LMWF showed a linear increase within the first half an hour of reaction. Afterwards, the MWDR kept constant at about 0.25. Acid hydrolysis of exopolysaccharides was systemetic scission, which followed the pseudo first-order kinetics. The obtained value of rate constant k was 3.24 × 10-2min-1, which was much less than that of random scission.

β-Cyclodextrin (β-CD) was used as the wall material for preparing clove oil microcapsule, and the slow-released antibacterial properties of the inclusion complex were tested. The results showed that the embedding rate was 21.79%. The antibacterial rate of newly prepared microcapsules did not reveal an obvious difference from that of the microcapsules subjected to more than one-month storage. Therefore, clove essential oil inclusion complex has slow-released antibacterial properties.

Melanoidin was extracted from black soy sauce, and its spectral properties and bioactive functions were studied. The results showed that 22.8 g of crude melanoidin could be obtained from 100 mL black soy sauce by organic solvent precipitation. The crude melanoidin was purified by removing small molecular substances with Sephadex G-50 column. The molecular weight of the purified melanoidin was in the range of 3000 to 55000 u. The UV-Vis and infrared spectra revealed that the crude melanoidin was products of the Maillard reaction and enzymatic browning. The scavenging efficiency of the crude melanoidin on DPPH free radicals and on hydroxyl free radicals were 89.0% and 89.5%, respectively. The inhibitory action on the synthesis of nitrosamine was up to 80.0%. Conclusion: crude melanoidin from soy sauce can be developed as a functional solid soy sauce. Neat melanoidin has great potential to developed as a functional food coloring.

A total of 42 samples were collected from honey samples of 5 different unifloral origins (each unifloral origin consisted of different geographic origins in China). Phenolic extract was obtained from these selected samples using Amberlite XAD-2 absorption resin. The contents of total phenolic acids and total flavonoids were spectrometrically determined, and reducing power and the scavenging activity against DPPH and superoxide anion free radicals were tested to evaluate the effects of floral origin, sample color and geographic origin on the antioxidant activity of honey. Total flavonoids content ranged from (9.41 ± 0.18) to (92.76 ± 0.13) mg/kg as determined using quercetin as the reference standard. The content of phenolic compounds ranged from (9.10 ± 0.05) to (149.57 ± 0.14) mg/100 g as determined using protocatechuic acid as the reference standard. Dark honey had the highest scavenging activity on DPPH and superoxide anion free radicals with EC50 of (0.042 ± 0.014) g/mL and (0.038 ± 0.009)g/mL, respectively. Conclusion: phenolic extracts from honey samples have impact on their antioxidant activity. The antioxidant potential is positively correlated with the contents of phenolic or flavonoid compounds. Dark honey has higher contents of phenolic and flavonoid compounds as well as stronger antioxidant potential than other light honey.

The stability of β-carotene emulsion in orange juice was evaluated under different preparation conditions and different storage temperatures. The effects of homogenization pressure, vitamin C concentration, arabic gum concentration and sterilization time on the stability of β-carotene emulsion in orange juice were monitored based on the changes in particle size and migration rate of β-carotene emulsion droplets during the first two hours and β-carotene content during two-week storage. The results showed that the best stability for β-carotene emulsion in orange juice was achieved under the conditions: homogenization pressure of 30 MPa, vitamin C concentration of 0.03%, Arabic gum concentration of 0.08% and sterilization time of 7 min. The stability of β-carotene emulsion in orange juice was also investigated at different storage temperatures. We found that β-carotene degradation could be fitted into a first-order kinetic model with a regression coefficient (R2) of 0.992. The logarithm of degradation rate constant against the reciprocal of absolute temperature revealed the best fit to the Arrhenius model with a regression coefficient (R2) of 0.961.

Peanut antioxidant peptide was prepared by sequential hydrolysis of peanut protein powder with Viscozyme L followed by alcalase. The effects of heat, food additive, preservative, metal ion, sterilization, pH and low temperature treatment on antioxidant properties in vitro such as DPPH radical scavenging activity, reducing power, ferrous ion chelating ability and anti-lipid peroxidation were investigated. The results indicated that heat treatment and food preservative treatment were beneficial for increasing the antioxidant activity of peanut antioxidant peptide. The addition of tartaric acid or citric acid had considerable impact on the antioxidant activity of peanut antioxidant peptide. Nevertheless, the antioxidant activity remained at a stable level in the presence of sodium chloride or sucrose. Copper ion also had an obvious effect on the antioxidant activity of peanut antioxidant peptide. Various sterilization processes were beneficial to the scavenging of DPPH free radicals, reducing power, ferrous ion chelating capacity, but could reduce the inhibitory rate of lipid peroxidation. The reducing power, ferrous ion chelating capacity and anti-lipid peroxidation could be enhanced under alkaline conditions, whereas acidic conditions could reduce the ferrous ion chelating capacity and anti-lipid peroxidation. Low temperature treatment could reduce the antioxidant activity of peanut antioxidant peptide.

Water content and dehydration rate of oyster subjected to microwave drying at various microwave intensities were determined. The effect of microwave intensity on rehydration rate, shrinkage rate and surface color of dried oyster were explored. The results showed that dehydration rate was improved and drying time was shortened with increasing microwave intensity. The time required for microwave drying of oyster was in the range of 3.5－30 min. Microwave dried oyster at middle intensity level such as 5 W/g or 8 W/g revealed better quality. A microwave drying kinetic model was established by the Page equation with excellent fitting degree.

In this study, myofibrillar proteins were extracted from the back muscle of common carp and the influence of konjac flour(0.05, 0.10, 0.15, 0.20 g/100 mL), temperature (70, 80, 90 ℃) and NaCl (0.05, 0.10, 0.15, 0.20 mol/L on gel properties of the proteins, including hardness, springiness, whiteness and water-holding capacity, was investigated. Generally, the hardness and springiness of myofibrillar protein gels formed in the presence of konjac flour were higher at 80 ℃ than at 70 ℃ and 90 ℃ (P ＜0.05). Gel hardness and springiness also increased due to the addition of NaCl. Myofibrillar protein gels exhibited a higher whiteness at 90 ℃ compared with 70 ℃ and 80 ℃. The water-holding capacity at 90 ℃ was significantly higher than that at 70 ℃ (P＜0.05), but showed no significant difference from that at 80 ℃ (P＞ 0.05). A significant increase in water-holding capacity was found with increasing NaCl addition. In addition, when konjac flour was added at a concentration of 0.10 g/100 mL, the highest gel strength was achieved for myofibrillar protein gels formed at the same temperature and reached 129 g at 80 ℃. As the concentration of konjac flour increased, gel whiteness decreased, while water-holding capacity increased. Moreover, the addition of NaCl resulted in a significant increase in gel whiteness.

Rhizobium leguminosarum 1.1723 was mutagenized by means of LiCl treatment followed by UV irradiation or ultrasonic treatment alone to yield coenzyme Q10-producing strains. The results showed that 1 g/L LiCl could obviously increase the positive mutation rate and that ultrasonic treatment could change cell wall structure of Rhizobium leguminosarum. A mutant C40-05 with high productivity of coenzyme Q10 was obtained through preliminary screening with roxithromycin and secondary screening by means of shake flask cultivation. Its coenzyme Q10 yield was up to 1.198 mg/g, which revealed a 208% increase compared with the original stain. Only 2.67% reduction in coenzyme Q10 yield of the mutant was observed after the fifth passage. Therefore, the obtained mutant is a stable strain that deserves to be studied further.

In this study, a lipase-producing strain, named as xjA, was isolated from soil near Riyuexing oil factory in Daqing. The solid-state fermentation conditions for lipase production by the strain were optimized using one-factor-at-a-time and orthogonal array design methods. Meanwhile, the prepared lipase was used to synthesize conjugated linoleic acid glyceride. The results indicated that the optimal fermentation conditions were wheat bran/soybean meal mass ratio of 1:4, culture medium/adding water volume ratio of 1:1, fermentation temperature of 29 ℃, inoculation amount of 0.3%, and fermentation time of 3 days. Under these conditions, the activity of lipase was up to 1450 U/g. The load rate of conjugated linoleic acid (CLA) in the conjugated linoleic acid glyceride synthesized using the obtained lipase was 13.6%.

In order to find the appropriate proteases for enzymatic preparation of angiotensin Ⅰ-converting enzyme (ACE) inhibitory peptides from shrimp shell, neutral protease, alkaline protease, bromelin and papain were evaluated for their effectiveness in hydrolyzing shrimp shell based on hydrolysis degree and ACE-inhibitory activity. It was found that both neutral protease and alkaline protease were more suitable for the preparation of ACE-inhibitory peptides from shrimp shell. The process conditions for hydrolyzing shrimp shell with neutral protease or alkaline protease were optimized by orthogonal array design method. The optimized alkaline protease hydrolysis conditions were hydrolysis temperature of 60 ℃, hydrolysis pH of 9.5, substrate concentration of 2.5 g/100 mL, enzyme concentration of 4000 U/g and hydrolysis time of 2.5 h, resulting in an ACE-inhibitory rate of 67.70% and a hydrolysis degree of 69.79%. The optimized neutral protease hydrolysis conditions were hydrolysis temperature of 50℃, hydrolysis pH of 7.0, substrate concentration of 2.5 g/100 mL, enzyme concentration of 2000 U/g and hydrolysis time of 2 h, resulting in an ACE-inhibitory rate of 84.04% and a hydrolysis degree of 26.76%. In conclusion, neutral protease is a superior protease over alkaline protease for the preparation of ACE-inhibitory peptides from shrimp shell.

Two crude polysaccharides, intracellular polysaccharide (IPS) and extracellular polysaccharide (EPS), were isolated from the cells and culture supernatant of Isochrysis galbana through hot-water extraction. The separation and purification of IPS and EPS, and their antimicrobial activities against Escherichia coli, Bacillus subtilis, Staphylococcus aureus and Proteus sp. were investigate, respectively. IPS was separated by ethanol-precipitation and purified by Sephadex G-75 gel chromatography, or by DEAE-52 column chromatography, while EPS was fractionated by Sephadex G-100 gel filtration chromatography. Finally, IPS and EPS were analyzed by UV and IR spectroscopy. The results indicated that: 1) IPS could inhibit the growth of Escherichia coli, Bacillus subtilis and Staphylococcus aureus. EPS could inhibit the growth of Escherichia coli and Bacillus subtilis. 2) IPS was separated into two fractions (IPS Ⅰand IPS Ⅱ) by DEAE-52 column chromatography. Both fractions could inhibit the growth of Bacillus subtilis and Staphylococcus aureus; EPS was separated by Sephadex G-100 gel filtration chromatography into three fractions (EPSA, EPSB and EPSC) with inhibitory activity against the growth of Escherichia coli; 3) The IR and UV spectra of IPS and EPS showed no ester protein, nucleic acid or pigment. Typical absorption curves of IPS and EPS revealed galactose frame with pyranglycoside linkage, while EPS did not exhibit sulfate radicals in the sugar linkage.

The succession of fungal microflora and the change of aflatoxin B1 (AFB1) during natural fermentation of Pixian horsebean paste were investigated using PCR-DGGE and ELISA analysis. The results showed that Aspergillus oryzae, Amylomyces rouxii, Rhizopus oryzae, Pichia anomala, and Debaryomyces hansenii were dominant during natural fermentation of Pixian horesebean paste, with A. oryzae as the predominant strain at both the starter propagation stage and incipient fermentation stage. A. rouxii and R. oryzae were the dominant strains during the starter propagation stage, while P. anomala and D. hansenii were the dominant strains during the incipient fermentation stage. The amount of AFB1 in all samples was less than the GB standard of 5μg/kg. During the starter propagation and incipient stages, AFB1 concentration revealed a gradual increase and then kept stable after the 14th day. Accordingly, more attention should be paid to the starter propagation stage for the biological control of AFB1.

Gompertz model was applied to fit the curves of growth and pH of five lactic acid bacterial strains isolated from cured fish with the purpose of analyzing the growth and acid-producing properties of lactic acid bacteria. The results indicated that Gompertz model could fit the growth and pH curves with high accuracy. Five lactic acid bacterial strains presented similar adaptability in the lag phase. The growth rates and acid productivities of Pediococcus acidilactici and Lactobacillus alimentarius were much higher than those of other strains. Meanwhile, both strains revealed the highest balanced total bacterial count and lowest balanced pH. Moreover, a significant correlation between the pH of the culture medium and total lactic acid bacteria count was observed.

Defatted pupa protein was prepared in our laboratory and used further to prepare ACE-inhibitory peptide by enzymatic hydrolysis. The best protease for preparing ACE-inhibitory peptide from pupa protein was chosen out of neutral protease, alcalase, papain, protamex, flavourzyme and trypsin. The hydrolysis process was optimized using response surface methodology. Neutral protease was found to be the best among all investigated proteases. The optimal hydrolysis conditions were determined as follows: substrate concentration of 11.88:100, hydrolysis temperature of 50.22 ℃, hydrolysis pH of 9.46, and enzyme concentration of 7.03%, hydrolysis time of 4 h. Under these conditions, pupa protein hydrolysate with an ACE-inhibitory rate of 41.98% was obtained.

In the present study, strains with degradation activity for biogenic amines were screened from naturally fermented fish sauce, and the effects of fermentation time and temperature on the content of biogenic amines were investigated. A total of 10 strains were obtained from natural fish sauce subjected to fermentation for 3 months. After 72 hours of fermentation at 30 ℃, the degradation rate of histamine was in the range of 17.3%－62.2%, and the degradation rate of tyramine was in the range of 12.4%－57.3%. The strain M8 with the highest activity was identified as Kodamaea ohmeri yeast through 26S rDNA sequence and online sequence alignment. Meanwhile, the strain revealed the strongest degradation activity for biogenic amines at 30 ℃. During fermentation, the content of biogenic amines revealed a decrease on the first day and an increase on the second day as well as the highest level on the third day, and then exhibited a decrease trend until the end of fermentation. After 9 days of fermentation at 30 ℃, the contents of histamine and tyramine were reduced to 30.4% and 20.8% of the initial levels, respectively. The strain M8 Kodamaea ohmeri yeast could reveal the best degradation activity for biogenic amines in the presence of 25% salt. Under the optimal conditions, histamine and tyramine were reduced to 35.6% and 27.6%, respectively.

The relative affinity of anti-bovine β-casein, κ-casein, E. coli O157:H7 IgY and IgG with their corresponding antigens was investigated using ammonium sulfocyanate and urea elution ELISA methods. The results indicated that three kinds of IgY had higher relative affinity with their corresponding antigens when compared to IgG. A significant difference between IgY and IgG against E. coli O157:H7 was observed, whereas slight differences were found for β-casein and κ-casein. Besides, the affinity of κ-casein with its corresponding antibodies showed an increase when compared to β-casein. Therefore, anti-κ-casein antibody is more suitable for the detection of milk samples than anti-β-casein antibody.

In order to improve the yield of resveratrol from Polygonum cuspidatum through endophytic fungi transformation, endophytic fungal strains capable of transforming polydatin from Polygonum cuspidatum were screened. The contents of resveratrol and polydatin were determined by high performance liquid chromatography (HPLC). The results indicated that 6 endophytic fungal strains capable of transforming polydatin from Polygonum cuspidatum were identified. Strain J1 had the highest transformation rate, 25.6%. The strain J1 was identified as Penicillium oxalicum with Genbank accession number of HQ732137 through morphologic observation and ITS-5.8S rDNA sequence analysis.

Cultivable Cd2+-resistant bacterial strains were isolated from burdock rhizosphere by pure culture, and Cd2+-resistant MIC and bacterial strain diversity were analyzed. The results showed that 10 Cd2+-resistant strains were isolated and identified as Bacillus subtilis, Enterobacter aerogenes, Enterobacter ludwigi, Klebsiella sp., Pectobacterium carotovorum and Pseudomonas sp. by 16S rDNA sequence. Among these strains, Pectobacterium carotovorum NP22, Enterobacter ludwigii NP23 and Pseudomonas sp. NP39 had the highest MIC, which was up to 400 mg/L Cd2+ on solid LB plate.

The fermentation conditions of Burkholderia cepacia NTG-15-03 for the production of lactobionic acid were optimized using one-factor-at-a-time method and response surface analysis based on quadratic regression orthogonal design. The optimal fermentation conditions for the production of lactobionic acid were fermentation pH of 7.0, seed age of 24 h, inoculation amount of 2% and fermentation time of 106 h. Under these conditions, the yield of lactobionic acid was up to 10.08 g/L.

The bioactive compound antrodin C was analyzed in the mycelia of A. camphorata in submerged fermentation. The fermentation medium for antrodin C production was optimized using Plackett-Burman design and response surface methodology. The results showed that glucose, soybean powder flour and MgSO4 were the major factors that influence the production of antrodin C. Box-Behnken design and response surface analysis were used to determine the optimal response value of the major factors. A quadratic regression model was established. Based on response surface analysis of the mathematical model, the optimal culture medium composition was determined as glucose 72.0 g/L, soybean flour 5.91 g/L and MgSO4 0.614 g/L. The predicted yield of antrodin C was 178.59 mg/L. After cultivation under the optimal conditions for 7 days, the content of antrodin C reached up to (177.83 ± 0.32) mg/L, which was 85.8% higher than before the optimization (95.72 mg/L).

Orange peels were fermented by Aspergillus niger to produce cellulase and amylase by solid state fermentation (SSF). The effects of orange peel and water contents in SSF medium, inoculum size and fermentation time on cellulose and amylase activities were explored by one-factor-at-a-time method. Based on the results obtained, the fermentation conditions for the production of cellulase and amylase were optimized by orthogonal array design to be orange peel content of 16 g, initial water content of 64 mL/100 g, inoculum size of 15% and fermentation time of 60 h. Under these fermentation conditions, the activities of cellulase and amylase were 1816 U/g and 196 U/g, respectively. This study suggests that solid state fermentation can provide a promising strategy for the production of cellulase and amylase from orange peels by Aspergillus niger.

SAU-2, a bacteriocin-producing strain, was screened out of 34 strains isolated from milk residue in West Sichuan plateau. The strain was identified as Enterococcus based on colonial morphology, physiological and biochemical characteristics and 16S rDNA sequence phylogenetic analysis. SAU-2 had no hemolytic activity. All the virulence factors of agg, gelE, cylM, cylB, cylA, esp, efaAfm, cpd, cob, ccf, cyILL, cyILS, fsrB and hyLEfm were negative. These results indicate that SAU-2 is safe. In addition, bacteriocin produced by SAU-2 could tolerate heat treatment at 121 ℃ for 20 min, and exhibited antibacterial activity at pH 2.0-12.0, but was sensitive to trypsin and proteinase K. It showed strong inhibitory effect on relative strains of SAU-2 and Gram-positive bacteria, and could also inhibit one strain of Pseudomonas aeruginosa and one strain of Rhodotorula glutinis, but had no inhibitory effect on other Gram-negative bacteria and fungi.

In order to determine the relationship between amino acid residue at the special site and the activity of Thermococcus. siculi HJ21 α-amylase, pEt-28a-His6 plasmid with TSA gene was used as a template for the site mutagenesis from Asp186 to Asn186. The activity of α-amylase with and without mutation was measured. According to the difference between per-mutant and mutant cDNA sequences, the secondary structure and three-dimensional structure of TSA protein were also predicted using DNAStar and Deepview protein analysis software. The results showed that Asp186 was of critical significance for maintaining the activity of T. siculi HJ21 α-amylase. The site-directed mutagenesis of T. siculi HJ21 α-amylase at position 186 changed the properties of secondary structure as well as hydrogen-bonding networks, thus resulting in the loss of its activity.

In this study, an acidic β-glucosidase (BGL) was purified from acid-tolerant Aspergillus niger L. mycelia by ethanol precipitation, DEAE-Sepharose column chromatography and Sephadex G-100 column chromatography. SDS-PAGE showed that the molecular weight of the enzyme was 125.7 kD. Further characterization revealed that it had maximal hydrolytic activity on p-nitrophenyl-β-D-glucopyranoside (pNPG) at pH 3.0 - 4.0 and 70 ℃ with a Km of 2.35 mmol/L and a kcat/Km of 2.99 × 104 mol/L ·s. The kcat/Km values for hydrolyzing geniposide and salicin were 1.26 × 104 L/(mol ·s) and 1.37 × 104 L/(mol ·s), respectively. The hydrolytic activity was activated obviously by Mn2+ but inhibited faintly by Fe2+, Zn2+ and Cu2+. The BGL was highly stable at pH 2.0 - 8.5, and 85% of its original activity could be maintained after 60 min of heat treatment at 65 ℃. Thus, the enzyme was highly stable to heat.

The cDNA sequence of isoflavone reductase-like gene IRL from Fagopyrum tataricum was amplified by RT-PCR. Sequencing showed that the ORF of IRL gene from F. tataricum (named as FtIRL) was 942bp, probably encoding a protein of 313 amino acids. Further analysis indicated that the deduced FcIFR protein had homology values of 97% with other plants, IRLs. FtIRL possessed two short-chain dehydrogenase/reductase conserved motifs: a substrate-binding pocket and a NADPH binding site. The phylogenetic tree constructed based on amino acid sequences indicated that, although the amino acid sequence of IRL gene from F. tataricum had high homology with that of isoflavone reductase (IFR) genes from other plants, its biological function might be more similar to that of pinoresinol lariciresinol reductase (PLR).

Objective: To explore the purification and properties of superoxidae dismutase (SOD) from Zophobas morio L. larvae. Methods: SOD were obtained from Zophobas morio L. larvae by salting-out, DEAE-Sepharose FF column chromatography and Sephadex G-75 column chromatography. SDS-PAGE was used to determine its molecular weight and atomic absorption spectrometer was used to identify it types. Results: SOD with highly specific activity was obtained. The purification factor was 68.54. The purified SOD was identified as Cu, Zn-SOD with molecular weight of 37.30 kD. It had an absorption peak at 278 nm and good stability. Its optimal temperature and pH were 40 ℃ and 6.0, respectively. Its high sensitivity to H2O2 and β-mercaptoethanol was found , while a mixture of CHCl3 and CH3CH2OH (3:5, V/V) had little effect on its activity. Conclusion: The SOD extracted from Zophobas morio L．larvae has high enzymatic activity, stability and application potential.

The preparation of fermented fish broth with high antioxidant activity from macheral meat with food-grade Bacillus subtilis was investigated in the present study. The results of one-factor-at-a-time experiments showed that highly antioxidant fermented fish broth was obtained under the fermentation conditions: medium volume of 50 mL or 100 mL in 250 mL shake flasks, glucose concentration of 2%, fish meat-to-water ratio of 1:(1－2 )(m/V), and rotation speed of 150 r/min. It was also found that glucose concentraiton, medium volume in 250 mL shake flasks and fish meat-to-water ratio were main parameters that influence the production of antioxidant ingredients. Using response surface methdology based on a Box-Behnken experimental design, the main fermentation parameters were optimized to be 3.98%, 96.02 mL/250 mL and 1:1.60(m/V), respectively. The fermented fish broth obtained under these conditions exhibited a DPPH radical scavenging rate of 94.52%.

The purpose of this study was to develop a fermentation strater culture and to optimize the fermentation conditions for fermented cabbage production. In this study, 16 strains including single strains of Lactobacillus plantarum, Lactobacillus pentosus and Leuconostoc mesenteroides isolated from Sichuan pickles and their combinations were first tested. Two different strain combinations were then selected out of them based on fermentation speed, nitrite content and fermented cabbage flavor for the optimization of fermentation by response surface methodology. The results showed that the optimal condition for cabbage fermentation by a mixture of Leuconostoc mesenteroides and Lactobacillus pentosus (1:2) or Leuconostoc mesenteroides Lactobacillus pentosus, and Lactobacillus plantarum(1:1:1) were 4 g/100 mL salt, 0.2% of inoculum size and 25 ℃ of fermentation temperature. Main effect analysis showed that salt concentration had the greatest effect on total acidity of fermented cabbage, followed by fermentation temperature and then inoculums size.

Based on peptide yield, nitrogen solubility index (NSI) and glucosinolate degradation rate, the production conditions for rapeseed peptide by mixed solid-state fermentation using Bacillus subtilis and Actinomucor elegans preliminarily determined by one-factor-at-a-a-time method and further optimized by response surface analysis coupled with Box-Behnken design. The optimal fermentation conditons were 4:1 of Bacillus subtilis-to-Actinomucor elegans ratio, 32.1 ℃ of fermentation temperature, 4.64 d of fermentation time, resulting in a peptide yield of 9.85% and a glucosinolate degradation rate of 67.83%.

The influence of spontaneous fermentation for different hours on pasting properties of four kinds of waxy rice was investigated. The results showed that the total solid content increased from 0.0067－0.0102 g/mL to 0.0247－0.0352 g/mL with fermentation time up to 96 h, whereas pH decreased from 6.0－7.0 to 3.0－4.0. Spontaneous fermentation significantly increased the viscosity of waxy rice (P＜0.05). After 96 h of fermentation, the peak viscosity of Anhui waxy indica rice, Thailand waxy japonica rice, Yutai waxy japonica rice and Yutai waxy indica rice increased from 231.46, 123.04, 205.00 RVU and 222.88 RVU to 290.00, 201.54, 224.71 RVU and 283.50 RVU respectively. In summary, spontaneous fermentation increases the viscosity of waxy rice.

Pumpkin seed protein isolate was hydrolyzed by acidic protease to prepare antioxidant peptides. One-factor-at-a-time experiments were done to explore the effects of enzyme concentration, pH, temperature, substrate concentration and hydrolysis time on the scavenging activity of pumpkin seed hydrolysate against DPPH free radicals. Enzyme concentration, susbstrate concentration and hydrolysis time were identified as main affecting parameters and optimized using response surface analysis based on a three-variable, three-level Box-Behnken design. The optimal hydrolysis conditions were determined as hydrolysis temperature of 50 ℃, hydrolysis pH of 2.5, enzyme concentration of 6000 U/g, substrate concentration of 0.05 g/mL and hydrolysis time of 5 h. Under these conditions, the scavenging activity of DPPH free radicals was up to 92.82%.

A strain of Monascus purpureu was treated with UV irradiation and its spore was then incubated in media containing LiCl to induce mutation. A mutant strain with high yield of monacolin K was obtained and its fermentation conditions were optimized for monacolin K production. The results showed that the optimal fermentation conditions were initial temperature of 30 ℃, late temperature of 24 ℃ and original moisture content of germinated brown rice of 60%. Under these conditions, the yield of monacolin K reached 5.33 mg/g.

The changes in chemical components of highland barley wine during fermentation with multi-strain starter were studied and compared with those of traditional fermented highland barley wine. The results showed that the dynamic change patterns of chemical components during fermentation with multi-strain starter and traditional starter were similar. pH value decreased rapidly at first and then kept stable at pH 4.0－4.3, the measured total acidity showed an increasing trend. Fermentation temperature increased first and then dropped gradually with the highest value of about 36.2 ℃. Saccharifying enzyme activity and reducing sugar content increased significantly during 0－24 h, and then decreased till the end of fermentation. Total sugar content kept decreasing throughout the whole process. The alcohol concentration fermented by multi-strain starter was 10.30% which indicated a significant (P ＜ 0.05) increase by 57.73% compared with that obtained using traditional starter. Both ammonia-N content and acid proteinase activity increased in the early stages of fermentation followed by a slow decrease. Total free amino acid (FAA) in the final product fermented by multi-strain starter was 80.923 mg/100 mL and no methionine was detected in it. Sensory evaluation showed that the optimal fermentation duration was 60－72 h for highland barley wine production by multi-strain starter. Under this condition, the product was acceptable and maintained the major flavor of wine fermented by traditional starter as evaluated by sensory evaluation.

Objective: To study the effect of rhein on the proliferation and oxidative damage of human umbilical vein endothelial cells (HUVEC). Methods: An oxidative injury model was established with H2O2. HUVECs were incubated with rhein at various concentrations and the availability of rhein for protecting endothelial cells was explored. The release rate of lactic acid dehydrogenase (LDH), the contents of malondialdehyde (MDA) and NO, and the activities of nitrogen oxide synthase (NOS), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were determined. Flow cytometry was employed to investigate the apoptosis of HUVECs. Results: Rhein had no obvious effect on the proliferation of HUVECs when the concentration of rhein was less than 16 μmol/L. However, rhein at a concentration of more than 2 μmol/L could reveal significant protection against oxidative damage in HUVECs. The release rate of LDH and the content of MDA revealed an obvious decrease, whereas the content of NO and the activities of NOS, SOD and GSH-Px exhibited an obvious increase. The rates of apoptosis and necrosis were reduced significantly. Conclusion: Rhein can maintain the normal physiology of the cells and prevent the cells from H2O2-induced injury at a concentration of 2-16 μmol/L. It is particularly important for the prevention and treatment of atherosclerosis.

Objective: To explore the promoting effect of egg white peptide binding with calcium (EWP-Ca) on calcium absorption in vivo. Methods: Totally 60 male Wistar rats were randomly divided into 6 groups: normal group, calcium-deficient model group, CaCO3 group and EWP-Ca groups at low, medium and high doses. Calcium-deficient model rats were fed a low-Ca diet, and calcium absorption-related indices were determined after a feeding period of 30 days. Results: EWP-Ca at high dose (106.4 mg/(kg ·d)) could significantly increase femur diameter, dry weight, calcium content and bone mineral density (P＜0.01) and could significantly decrease the activity of serum alkaline phosphatase (AKP) (P＜ 0.01) when compared with calcium-deficient model control group. Moreover, compared with CaCO3 group at the same calcium level, femur diameter (P＜0.01) and bone calcium content (P＜0.05) were significantly increased. Conclusion: EWP-Ca can promote calcium absorption in vivo, which is better than CaCO3 at the same calcium level.

In the present study, the antioxidant activity of resveratrol in vitro was evaluated based on DPPH radical scavenging capacity, ABTS free radical scavenging capacity and reducing power, respectively. Meanwhile, the oxidation model of red blood cells induced by hydrogen peroxide and liver lipid peroxidation model were used to explore the inhibitory effect of resveratrol on free radical-induced damages and lipid peroxidation. The results showed that resveratrol had strong scavenging activity against free radicals and inhibitory effect on oxidative damage induced free radicals in a dose-dependent manner.

Objective: To determine the nutrients and quality of red bud taro (Colocasia esulenla (L.) Schott). Methods: The nutritional value and ingredients of red bud taro were examined and evaluated according to relevant national standards. Results: The contents of crude protein, crude fat, crude fiber, starch, ash and water in red bud taro were 2.18%, 0.096%, 1.37%, 13.40%, 0.76% and 82.88%, respectively. The contents of carotene, ascorbic acid, thiamine and riboflavin were 7.714, 0.069, 0.117 mg/100g and 0.204 mg/100 g, respectively. The contents of mineral elements K, P, Ca, Mg, Na, Fe and F were 95.87, 23.88, 7.92, 3.60, 0.10, 0.06 mg/100 g and 9.93 × 10-3 mg/100 g, respectively. The contents of essential (EAA), non-essential (NEAA), and total amino acids (TAA) were 39.87%, 56.37% and 96.24%, respectively. The amino acids score (AAS), chemical score (CS), and essential index (EAAI) were7.38, 5.47 and 56.12, respectively. Additionally, the EAA/TAA and EAA/NEAA ratios were 41.43% and 70.73%, respectively. Moreover, the content of flavor amino acids was 40.43% based on total amino acids. Conclusion: Red bud taro is rich in carbohydrates, proteins, vitamins and mineral elements and low in fat so that it reveals high edibleness and great development prospects.

Health improvement will become one of the most important challenges for countries in the 21st century. The consumption of healthy foods is the best way for people to prevent chronic disease. In this paper, the interactions among food compositions, microbes and their metabolites in the intestine as well as intestinal structure and functions are summarized. The gastrointestinal tract plays a vital role in whole-body homeostasis, whereas foods can provide nutrients and regulate biological activity to affect the initial events of a phenomenon and the mid-term bidirectional effects.

In recent years, plant growth regulators are widely used in agricultural products. As the toxicity of plant growth regulator residues has gained increasing concerns, trace analysis methods for plant growth regulators have been developed. In this paper, the major methods with advantages and disadvantages for the analysis of plant growth regulator residues in fruits and vegetables are summarized, including gas chromatography (GC), high performance liquid chromatography (HPLC), chromatographic technique combined with mass spectrometry, enzyme-linked immunosorbent assay (ELISA), capillary electrophoresis (CE) and so on. Meanwhile, the development prospects are also discussed.

Autolysin is a kind of peptidoglycan hydrolase produced by the bacteriumb and able to degrade its own cell wall. This enzyme is involved in numerous cellular processes including cell division, cell-wall turnover and bacterial lysates. Autolysin is closely associated with pathogenicity, which participated in host cell adhesion and invasion. The protein structure, physiological function and pathogenicity of autolysins in Listeria monocytogenes, such as p60, Ami, IspC, Auto and MurA are reviewed here.

Biological removal of mycotoxin is now under extensive study. Besides some microenzymes that can transfer mycotoxin into non-toxic or less toxic products via chemical modifications, the removal of mycotoxin can also be completed through the adhesion of microbial cell walls to toxins. This adhesion technique is related to microbial surface components and structural characteristics. The interactions between the microbial cell surface structure and toxin binding are reviewed in this paper. Meanwhile, the current research situation, binding mechanisms and infulencing factors are discussed. This study will provide some references for future studies on the biotransformation and removal of mycotoxin.

This paper provides a review of tehcniques for the application of fish oil in foods products. Fish oil has been widely used in food products due to its special health benefit. It is necessary to add fish oil in food products because of deficient intake of docesahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in China. Nowadays, there are many foods rich in fish oil avabiale in the market. The oxidative stability of fish oil has been a concern for a long time during this application. The addition styles such as direct addition, emulsion or microcapsulation, and new processing techniques can effectively improve the oxidative stability of fish oil. Therefore, the application of fish oil in daily food will be developed widely in future both technologically and commercially.

Dietary fiber plays a very important role on human health. Edible fungi are a new resource of dietary fiber. Dietary fiber added to foods can not only exert its healthy function, but also improve food quality. Therefore, edible fungi will have a wide exploitation prospect. In this paper, the composition, function properties, modification methods and application situation of dietary fiber from edible fungi are reviewed with the aim of providing some references for its comprehensive exploitation and utilization.

Starch is one of the major components in Chinese chestnut, which is highly correlated with its glutinous characteristics. Meanwhile, protein and fat in the starch also have impact on the glutinous taste. In this paper, the correlation between chestnut starch complex (starch granule-associated with protein and starch-lipid complex) and glutinous taste is reviewed. Moreover, the industrial application and limitations of Chinese chestnut products are discussed.

The view of food safety is a historical and relative concept. With the development of science and technology, as well as the development of productivity and the improvement of people, s living standards, the understanding of food safety has gained extensive attention. Food safety is also a systematic and overall concept, which is related to food production, circulation and consumption as well as the involvement of biological, chemical, medicinal, physical and other fields. Establishing systemic food safety to guide food production, circulation and consumption is a good way to solve the problem of food safety and ensure the fundamental interests of consumers.

Food safety has been widely concerned, and food safety problems caused by ink from packaging materials have frequently taken place. In this paper, the regulations and requirements of packaging inks for foods are discussed and the situation of ink migration from packaging material to food and food stimulants is summarized with the aim of providing a legal basis and experimental guidance for future research.

Rare ginsenoside compound K (CK) is a non-natural diol-type saponin. It is a metabolic product from other diol-type saponins in human intestine. Due to its anti-tumor and other beneficial effects, plenty of ginsenoside CK are needed to meet the needs of medical care and scientific research. For this resson, attempts have been done to produce ginsenoside CK effectively under human controlled conditions. In this paper, we review recent progress on ginsenoside CK preparation by microbial transformation, with the purpose to provide some references for future development of better methods to produce ginsenoside CK.

Steamed bread is a traditional staple food in China, which is very popular. Along with the development of staple food industrialization, the stabling of steamed bread is always a difficult problem. Therefore, the study of the stabling mechanism of steamed bread has great significance. In this paper, recent research advances at home and abroad are reviewed. Meanwhile, the factors that infulence steamed bread staling are also discussed. Moreover, some strategies for retarding the staling process through improving major ingredients, storage temperature, water content, processing technology and additives are proposed.