The spoilage potential of Shewanella putrefaciens and Pseudomonas fluorescens to Pacific white shrimp and their interaction were evaluated by inoculating pure and mixed cultures into sterile shrimp juice. Changes in total bacterial count, total volatile basic nitrogen (TVB-N), and the contents of amino acids, biogenic amines, myogen and volatile compounds were monitored during 8 days of culture at (4 ± 1) ℃. A control was prepared by adding sterile water into shrimp broth. The results showed that the maximum viable counts of S. putrefaciens and P. fluorescens in co-culture were 8.85 and 8.26 (lg(CFU/mL)), respectively, which were higher than their monocultures. The results of spoilage capacity showed that higher TVB-N content and putrescine production were observed in the co-culture when compared with the single cultures. It is concluded that S. putrefaciens grew well than P. fluorescens and that both bacteria could mutually enhance growth and accelerate the spoilage of Pacific white shrimp juice.

In order to explore the molecular mechanism by which fresh-cut handling accelerates the senescence and quality deterioration of Zizania latifolia, the dynamic proteome changes of whole (control) and fresh-cut Z. latifolia during storage at room temperature (25 ℃) for 0, 3 and 5 days were investigated by using two-dimensional electrophoresis (2-DE). Approximately 660 protein spots were detected on the gels. Totally 39 spots showed a significant (P < 0.05) change in protein abundance based on 2.0-fold difference of which 35 were successfully identified by matrix-assisted laser desorption/ ionization time of flight mass spectrometry compared to the whole Z. latifolia. They could be categorized into seven functional groups, including signal transduction (8.6%), metabolism (22.9%), cell structure (8.6%), stress response and defense (31.4%), protein synthesis (11.4%), senescence (5.7%), and unclear functional proteins (11.4%). During storage, the expressions of 14 spots increased while the other 21 were down-regulated in the whole stem. Meanwhile, six spots (plant basic secretory protein, adenosine kinase, C2 domain, class III peroxidases, LbH_gamma_CA_like, and small Rasrelated GTP-binding protein), which were down-regulated in whole Z. latifolia, were up-regulated in fresh-cut Z. latifolia during storage, suggesting that these proteins may play important roles in the response to wounding stress. Also, fresh-cut significantly promoted the tendency for 14 up-regulated and other 15 down-regulated proteins. These results imply that the promotion of senescence and quality deterioration of Z. latifolia after fresh-cut processing may be due to the production and transduction of wounding signals, the acceleration of carbohydrate and nucleotide catabolism, the disorder of energy homeostasis and the enhancement of free radical damage, as well as the degradation of cell structure.

The objective of this study was to investigate the differences in the color, myoglobin (Mb), malondialdehyde (MDA), oxymyoglobin (OMb) and metmyoglobin (MMb) contents, antioxidant enzyme activities and total antioxidant capacity of longissimus dorsi muscle (LDM) from cashmere goats subjected to two grazing conditions (pasture and mountainside). The results showed that redness value, catalase and peroxidase activity and radical scavenging capacity of LDM from pasture-grazed goats were significantly higher than those of mountainside-grazed goats (P < 0.05), while lightness value, yellowness value, and MMb and MDA contents of LDM from pasture-grazed goats were significantly lower (P < 0.05). However, as far as Mb and OMb contents and superoxide dismutase activity in goat meat were concerned, no significant difference existed between two grazing conditions (P > 0.05). Consequently, the meat from pasture-grazed goats had higher antioxidant capacity than the mountainside-grazed goats due to the consumption of abundant amounts of green herbage and appropriate exercise, which helped improve antioxidant enzyme activities and meat color stability and maintain the balance between the generation and scavenging of free radicals.

Waste liquid from glycyrrhizic acid extraction was extracted with n-hexane, chloroform, ethyl acetate and n-butyl alcohol sequentially. The inhibitory effects of the resulting extracts on α-glucosidase were studied compared to identify the one with the highest inhibitory effect. The inhibition type was evaluated based on the Lineweaver-Burk plot and synergistic interaction between the selected extract and acarbose was analyzed by combination index. The chemical structure and amounts of the major components of the extract were determined using ultra-high performance liquid chromatography-diode array detection-mass spectrometry following acid hydrolysis by comparison with standards. The results showed that the ethyl acetate extract had the strongest inhibitory activity against α-glucosidase through competitive inhibition with an half maximal inhibitory concentration value of 0.152 9 g/L and an inhibition constant (Ki) value of 0.085 1 g/L, and synergistic effect existed between acarbose and the ethyl acetate extract. The major constituents of the extract were monoglucosides and diglucosides of glycyrrhizin, naringenin, isoliquiritigenin and formononetin. The contents of the flavonoids glycyrrhizin, naringenin, isoliquiritigenin and formononetin were 28.08%, 2.95%, 11.80% and 4.38% respectively. The content of total flavonoids was 47.21%.

Sterile turbot fillets were inoculated with Shewanella putrefaciens SP22 in pure culture or in co-culture with Hafnia alvei Ha-01 and then stored at 4 ℃. The microbial and physicochemical indexes (including total viable count (TVC), total volatile basic nitrogen (TVB-N) value, K value, Ca2+-ATPase and ultrastructural change) were measured after different periods of storage. The aim was to evaluate the spoilage potential of the pure and mixed cultures on turbot fillets. The results indicated that the TVC, TVB-N and K values of inoculated fish fillets increased significantly faster than those of the uninoculated control, and the samples inoculated with the co-culture showed the fastest increase. The Ca2+-ATPase activity of the inoculated samples decreased significantly faster than that of the control group and the co-culture group showed the fastest decrease. The rate of degradation of muscle proteins in the inoculated samples was clearly faster than that of the control group as observed under scanning electron microscope. In conclusion, Shewanella putrefaciens SP22 could cause turbot spoilage, and when co-cultured with Hafnia alvei Ha-01, it could lead to turbot fillet spoilage obviously during refrigerated storage.

Acid-soluble collagen (ASC) was extracted from the bone of Yunnan bream using cold acetic acid, and its amino acid composition, subunit composition, Fourier transform infrared (FTIR) and UV absorption characteristics, thermal stability and X-ray diffraction (XRD) characteristics, microstructure, peptide fragments and solubility were analyzed. Amino acid analysis showed that ASC mainly consisted of Gly, Pro and Ala, as well as lesser amounts of Tyr, Met, and Cys. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis confirmed ASC to be typical I collagen. The maximum absorption peak of ASC appeared at 230 nm. The FTIR and XRD spectra proved that the helical structure of ASC remained intact. Differential scanning calorimetry showed that ASC had two denaturation temperatures of 86.5 and 226.2 ℃ indicating high thermal stability. Scanning electron microscopy showed that the microstructure of ASC was homogenous with a smooth surface. Peptide analysis showed that amino acid sequence of ASC was Gly-X-Y, which was in agreement with the primary structure characteristics of collagen. The solubility of ASC was relatively high under acidic conditions (pH < 4), whereas it dropped sharply when NaCl concentration was higher than 4%.

The objective of this paper was to evaluate the potential of radish seed protein extract (RSPE) for use as an aquatic product preservative. The bacteriostatic effect of RSPE against 28 strains of sturgeon spoilage bacteria was investigated and its stability against heating, pH, ultraviolet (UV) irradiation, metal ions, surfactants and proteases was evaluated as well. RSPE was shown to inhibit 8 Aeromonas, 7 Pseudomonas, 11 Enterobacteriaceae and 2 other strains isolated from spoiled sturgeon. RSPE remained over 79.00%, 72.00% and 94.00% of its original antimicrobial activity after 30 min of treatment at 80 ℃, 2 h of treatment at pH 2.0–8.0 and 0–24 h of UV irradiation, respectively. RSPE was sensitive to Ag+ but was insensitive to 13 other metal ions including Pb3+, Mg2+ and Li+. In addition, surfactants such as urea, Tween 20 and Span 80 had little effect on the antimicrobial activity of RSPE. RSPE remained over 96.00% of its original antimicrobial activity after enzymatic treatment with trypsin, papain, neutral protease or proteinase K at different concentrations. It can conclude that RSPE has potent bacteriostatic effect against sturgeon spoilage bacteria and good stability to heat, acid, UV light, proteases, surfactants and metal irons. Thus, it has the potential to be developed as an aquatic product preservative.

Cronobacter sakazakii is an opportunistic pathogen transmitted by foods, which has been implicated in several forms of neonatal infections such as bacteraemia, necrotizing enterocolitis and neonatal meningitis. The aim of this study was to evaluate the antibacterial activity of plant-derived compounds to obtain potent antimicrobials. The antibacterial activity against C. sakazakii was determined by the Oxford cup method. Moreover, the minimum inhibitory concentration (MIC) against four American Type Culture Collection (ATCC) strains and five foodborne isolates was assessed using agar dilution method. Results indicated that 40 phytochemicals had obvious bacteriostatic action against C. sakazakii, and the diameters of the inhibition zones produced by 7 compounds (carvacrol, thymoquinone, thymol, cinnamaldehyde, citral, protocatechuic acid and protocatechualdehyde) were more than 13 mm. Among to 50 compounds tested, thymol and carvacrol had the most potent antimicrobial activity against 9 C. sakazakii strains with MICs ranging from 0.1 to 0.2 mg/mL. Thymoquinone, cinnamaldehyde, citral and protocatechualdehyde also demonstrated good antibacterial effect with MICs of 0.30 to 1.25 mg/mL. The MICs of ferulic acid, chlorogenic acid, syringic acid, lipoid acid, protocatechuic acid, epicatechin, caffeic acid, paeonol and cichoric acid ranged from 2.50 to 5.00 mg/mL. These findings suggest that some plant-derived compounds exhibit good antimicrobial effect against C. sakazakii strains and could be potentially used to control C. sakazakii during food processing, circulation and storage.

The physicochemical properties (protein, fat and moisture content, and pH) and functional properties (textural properties, stretchability, meltability, free oil and rheological properties) of natural and processed Mozzarella cheese were measured. The results indicated that the protein content of natural Mozzarella cheese was significantly higher than that of processed Mozzarella cheese, accompanied by a significant decrease in moisture content and pH, and the fat content varied among different brands. Hardness, stretchability, meltability and free oil were significantly higher in natural Mozzarella cheese than in the processed one. Dynamic temperature sweep tests showed that the dielectric loss tangent (tan δ) of both natural and processed Mozzarella cheeses increased first and then decreased with increasing temperature. The tan δ of natural Mozzarella cheese reached 1 at 50–60 ℃ whereas that of processed Mozzarella cheese remained lower than 1 in the whole temperature range. Our findings suggested that natural Mozzarella cheese is more suitable for making baked foods, such as pizza and baked rice while processed Mozzarella cheese can be used in foods that do not need to be baked, such as sandwich.

In order to improve the quality of soybean milk, this study investigated the effect of soybean natural aging time on the quality of soybean milk in terms of soluble solid content, fat content, protein content, protein recovery, stability, precipitability and particle size distribution. Changes in the type and amount of volatile compounds were analyzed by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry. The results showed that compared with the control group (equilibrated for 10 h at 20 ℃ and 47% relative humidity), the contents of soluble solids, fat and protein in soybean milk made from soybeans with natural aging for 12 months decreased by 2.8%, 13.79% and 9.4%, respectively; the extraction rate of protein decreased by 1.73%; the stability decreased by 12.82%; the centrifugal sedimentation rate increased by 48.78%; the particle size distribution moved toward right and the average particle size increased from 229.6 to 312.9 nm; the content of main odorous substances increased by 7.24%, and the content non-odorous substances decreased by 0.93%. These results revealed that with the increase of soybean natural aging time, both physicochemical properties and flavor quality of soybean milk declined.

The antioxidant activity in vitro and inhibitory effect of rosemary extract on lipid and protein oxidation in salami were assessed. The total phenol content of rosemary extract was measured, and its 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging effect, the oxygen radical absorbance capacity (ORAC) and reducing power were investigated. The effect of adding different amounts of rosemary extract to salami on the content of thiobarbituric acid reactive substances and total protein thiol content was addressed during salami processing. The results showed that the total polyphenol content of rosemary extract was 197.6 mg/g. Rosemary extract at concentrations greater than 80 μg/mL possessed higher DPPH radical scavenging activity than sodium D-isoascorbate (P < 0.05). Its ORAC was 2 920.3 μmol Trolox/g, which was significantly higher than that (1 746.9 μmol Trolox/g) of sodium D-isoascorbate (P < 0.05). There was no significant difference in reducing power between rosemary extract at a certain concentration and sodium D-isoascorbate (P > 0.05). The addition of rosemary extract at 0.02% or 0.03% could more effectively inhibit lipid oxidation in salam than sodium D-isoascorbate at 0.02% (P < 0.05). The addition of rosemary extract at 0.03% showed significant inhibitory effect on protein oxidation and the effect was comparable to that at 0.02% (P < 0.05) . This experiment confirmed that rosemary extract has good antioxidant activity in vitro and as an efficient free radical scavenger and natural antioxidant, it can significantly inhibit lipid and protein oxidation during the processing of salami.

The purpose of this study was to explore the effect of ultrasonic treatment on the properties of O/W emulsion containing soybean protein isolate-chitosan (SPI-CS) complex. The relationship between surface hydrophobicity, emulsifying activity and emulsion stability and oil-water interfacial tension, particle size and stability of the emulsion were investigated. The results showed that surface hydrophobicity, emulsifying activity, emulsion stability and interfacial adsorption of SPI-CS without ultrasonic treatment were relatively low, and the particle size of the formed O/W emulsion was about 100 μm. The zeta potential of the emulsion was low and the droplets tended to aggregate. Creaming index was the highest after storage for 7 days. Ultrasonic treatment of SPI-CS formed emulsions with markedly improved properties. The O/W emulsion became more stable with increasing ultrasonic power, and it had the highest stability and lowest creaming index at 400 W. However, when the ultrasonic power exceeded 400 W, the particle size of emulsions was increased under light microscope, and zeta potential, emulsifying activity, emulsion stability and interfacial tension decreased obviously. Ultrasonic treatment exposed the internal structure of SPI protein molecules, unfolded part of the protein structure and increased molecular flexibility, thereby promoting the electrostatic interaction between chitosan and the protein, which indicated that ultrasonic-treated SPI-CS could affect the stability and relevant properties of O/W emulsion.

High voltage electrostatic field, a physical processing technology, has been used in the food industry in recent years. However, there is little research on its impact on oil processing. In this study, we treated soybean oil with high voltage electrostatic field to explore its effect on the oxidation of soybean oil by evaluating the changes in peroxide value (POV), acid value (AV), carbonyl value (CV), anisidine value (AnV) and the relative contents of typical fatty acids. The results showed that the best suppression on the oxidation of soybean oil was observed when the field strength was 150 kV/m. At this electric field intensity, the inhibitory effects of three antioxidants: tea polyphenols, phytic acid and tert-butylhydroquinone on the oxidation of soybean oil were investigated. It turned out that 150 kV/m high voltage electrostatic field could result in the oxidation of soybean oil suppression. The percentage inhibition of POV, AV, CV and AnV by tea polyphenols was enhanced to 34.4%, 67.6%, 66.0% and 55.0%, respectively, thereby effectively alleviating the oxidation of soybean oil. Our conclusion may provide a novel direction for the suppression of soybean oil oxidation.

This work aimed to study the effects of high hydrostatic pressure (HHP) and enzymatic hydrolysis on the antigenicity of type I collagen from the skin of Oncorhynchus mykiss. The results indicated that the antigenicity of HHPtreated type I collagen decreased initially and then increased with the increase of pressure. Moreover, the antigenicity of type I collagen was reduced by up to 42.66% after 10 min HHP treatment at 200 MPa and 25 ℃. On the other hand, by comparing the effect of protease papain, α-chymotrypsin and trypsin on reducing collagen antigenicity, we obtained the optimal enzymatic hydrolysis conditions that achieved maximum antigenicity reduction (97.69%) as follows: 45 ℃, pH 8.0, enzyme-to-substrate ratio 1:10. Our results showed that the antigenicity of type I collagen from Oncorhynchus mykiss skin could be reduced by both high hydrostatic pressure and enzymatic hydrolysis and that enzymatic hydrolysis was more effective than high hydrostatic pressure. Thus, these results can provide useful information for allergen reduction.

In recent years, walnut allergy is commonly reported as tree nut allergy responsible for severe anaphylactic reactions. Different processing treatments can change the chemical and physical properties of walnut allergen proteins (Jug r 1), thereby affecting their allergenic properties. In this study, we evaluated the effect of different thermal treatments on the allergenic properties of walnuts. The antigenicity of walnuts subjected to different thermal treatments including wet heating, dry heating, high-pressure heating, and microwave heating was evaluated by immunoglobulin (Ig) E/IgG-immunoblot analysis. Our results showed both wet heating and high-pressure heating effectively reduced the content and antigenicity of walnut proteins and high-pressure heating was more effective (P < 0.05), while microwave heating had the opposite effect. These results can provide a scientific basis for developing hypoallergenic/no-allergic walnut products.

In order to understand the difference between domestic activated carbon (ACP) and foreign activated carbon (ACD) in the decolorization efficiency of zein, the decolorization efficiency and microstructure of ACP and ACD were compared. The results showed that there was no significant difference between the decolorization efficiencies of zein solution and extract, but the pigment adsorption rate of ACP (77.31%) was higher than that of ACD (67.27%). Furthermore, scanning electron microscopic analysis showed that the structure of ACP was extended inwards while the structure of ACD was less porous. Then, specific surface analysis and pore size analysis showed that the specific surface area and total pore volume of ACP (1 438.082 m2/g, 1.310 cm3/g) were bigger than those of ACD (779.809 m2/g, 0.626 cm3/g) because there were more micropores and mesopores in the structure of ACP. Meanwhile, the surface of ACD showed more carboxylic acid and lactone functional groups, which could enhance the chemical adsorption of activated carbons effectively when bound to the hydroxyl groups in the pigment molecules. Simultaneously, ACD was more homogeneous in particle size, which was beneficial to the solid-liquid separation after decolorization. Taken together, ACD is more suitable for zein decolorization.

Studying starch granular structure is the basis for starch modification and extended scope of application. In the present work, the effect of high hydrostatic pressure (HHP) treatment on the granular structure of sweet potato starch was investigated by scanning electron microscope, X-ray diffraction, differential scanning calorimetry, Fourier infrared transform spectroscopy and rapid visco analysis. The results showed that surface morphology of starch granules was not significant changed after treatment at 200–500 MPa. When the pressure increased up to 600 MPa, the starch granules began to collapse and coagulate, thereby losing birefringences; the peak viscosity, trough viscosity and final viscosity were enhanced by 9.15%, 27.18% and 20.21% (P < 0.05), respectively; and the pasting temperature and peak time were increased by 1.9 ℃ and 1.16 min, while the pasting enthalpy and breakdown viscosity were decreased by 46.18% and 66.46% (P < 0.05). In addition, the crystal type and molecular groups of sweet potato starch remained unchanged after HHP treatment.

The effects of different heat treatments (hot water bath, microwave heating and radio frequency heating) and final temperatures (70, 80 and 90 ℃) on physicochemical properties and structure of zein were investigated. The results showed that three heat treatments could enhance the water solubility, emulsifying capacity and free thiol content of zein, and the effect increased with the increase in final temperature. The solubility, emulsifying capacity and of free sulfhydryl content of radio frequency treated samples at final temperature of 90 ℃ were increased by 74.65%, 171.7% and 53.94%, respectively. By differential scanning calorimetry, it was found that protein denaturation temperature increased slightly after microwave treatment. Furthermore, ultraviolet spectroscopy showed that the unfolding of the protein molecule associated with group exposure was induced by microwave and radio frequency, which improved the solubility and emulsifying ability of the protein. Meanwhile, Fourier transform infrared spectroscopy showed that heat treatment altered the secondary structure of zein, and the effects of microwave and radio frequency treatment were more pronounced.

This study aimed to explore the shaping of needle-shaped green tea at variable temperature and variable frequencies and to reveal the underlying mechanism for the purpose of providing the basis for automated shaping of needleshaped green tea. The effects of different variable-temperature variable-frequency shaping regimes on the quality of tea were compared, and the intrinsic mechanism underlying the shaping process was elucidated. The results showed that the tea samples produced by “high-high-middle” shaping scored highest (93 points) in sensory evaluation, having a fresh chestnutlike aroma, a fresh and mellow taste and a green and bright color. The ?a* values of the tea, tea infusion and tea leaves were 0.47, 5.07 and 3.33, respectively. The contents of tea polyphenols, amino acids, soluble sugar and chlorophyll in the tea were 28.65%, 2.64%, 3.78% and 3.68 mg/g. The moisture content showed no significant change during the early period of shaping at constant temperature and frequency, while the leaf temperature, caloricity and enthalpy increased quickly, reaching 64.4 ℃, 4.88 kJ/(kg/℃) and 173 kJ/kg at 3 min, respectively. During the middle period of shaping, the moisture content continuously decreased and the leaf temperature rose, accompanied by unchanged caloricity and a rapid decrease of enthalpy. During the late period of shaping, the moisture content fell rapidly, and the leaf temperature rose slowly, along with a simultaneous decrease in caloricity and enthalpy. At the end of shaping, the lowest enthalpy of 147 kJ/kg was observed. The entropy change reduced gradually but was always greater than zero, suggesting that the shaping process was irreversible. The average rate of water loss was 2.78%/min. The heat absorbed at different stages of the shaping process played different roles. Temperature rise mainly occurred at the early stage, both water loss and temperature rise mainly occurred at the middle stage, and the late stage was dominated by water loss, followed by temperature rise. To sum up, high temperature and high frequency for the early stage followed by proper reduction for the late stage helped the formation of green color and fresh and mellow taste in needle-shaped tea

Macadamia (Macadamia ternifolia F. Muell.) oils were obtained by spiral hot pressing, spiral cold pressing and hydraulic pressing methods. The fatty acid compositions of the oils were analyzed by gas chromatography-mass spectrometry. The color, quality indexes and total phenolic contents were determined by comparing with walnut oil as a control. The scavenging capacity against hydroxyl, superoxide anion and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonate free radicals (ABTS+·), and reducing power were investigated by comparing with walnut oil and rutin as controls. The results indicated the quality of the oil obtained by hydraulic pressing was improved compared with those obtained by other pressing methods; color parameters L, a and b values of the oil were 99.78, ?1.44 and 2.99, respectively, acid value was 0.648 6 mg/g, and peroxide value was 0.466 8 mmol/kg. The oil obtained by hydraulic pressing contained five unsaturated fatty acids, together accounting for 83.89% of the total fatty acids, including linoleic acid (62.66%), palmitoleic acid (16.75%) and octadecenoic acid (1.47%), as well as 679.11 μg/mL of total phenolics. All of the oils showed concentration dependent antioxidant activity, which could strongly scavenge hydroxyl and superoxide anion free radicals and also exhibited scavenging activity against ABTS+· as well as reducing power. The hydroxyl free radical (half maximal inhibitory concentration (IC50) = 1.31 mg/mL) scavenging activity and reducing power (IC50 = 14.78 mg/mL) of the oil obtained by hydraulic pressing were stronger than those of other oils but weaker than rutin. In addition, the superoxide anion radical scavenging activity (IC50 = 0.029 mg/mL) was higher than that of cold-pressed oil and rutin but lower than that of hotpressed oil and walnut oil at the same concentration, whereas the opposite was observed for ABTS+· scavenging activity (IC50 = 12.88 mg/mL). Correlation analysis showed that total phenolic contents in macadamia oils obtained by different pressing methods and walnut oil had good correlations with their hydroxyl and ABTS+· scavenging capacity and reducing power with R values of 0.951 9, 0.910 7 and 0.939 4 (P < 0.01), respectively.

The aim of the present study was to explore the regulatory effect of probiotics on the intestinal microbial diversity and abundance in patient populations with intestinal diseases. A probiotic preparation (PPr) was regularly consumed at a constant amount for 6 weeks by healthy, constipated, diarrheal, abdominal bloating, irritable bowel syndrome and irregular defecation populations. Before, during and after the experiment, fecal samples were collected for bacterial genomic DNA extraction. The sequencing of 16S rRNA V3 region was performed with the Personal Genome Machine (PGM, Ion Torrent). The sequencing data were used for diversity analysis by bioinformatics and multivariate statistical analysis. When the sequencing depth was satisfactory, the effect of the probiotics in correcting gut microbiota imbalance in the subjects was evaluated at the four levels of phylum, family, genus and even species. All sequencing reads were divided into 2 320 operational taxonomic units at a 97% similarity level. Bacteroidestes, Firmicutes, Proteobacteria and Actinobacteria were the dominant phyla, accounting for 99.81% of the total number of sequences. For all the subjects, the probiotics had a longlasting positive impact on Lachnospiraceae whereas Alcaligenaceae, Rikenellaceae, Bifidobacteria (Bifidobacteriaceae) and other dominant bacteria returned to the pre-intervention level when the intervention was withdrawn. The effects of probiotics on gut microbiota were different among all patient populations, and both Cyanobacteria and Fusobacteria were detected in the constipation group after consumption of the priobiotics. Principal component analysis (PCA) analysis showed that the regulatory effect of the probiotics in the diarrheal group was superior to that in two other groups during the first to the fourth week of intervention. The diversity and abundance of 10 genera including Faecalibacterium, Acinetobacter, Blautia, Clostridium, Dialister, Eggerthella, Granulicatella, Lactobacillus, Oxalobacter, Pyramidobacter were significantly increased in the diarrheal group, while only three genera: Prevotella, Megamonas and Collinsella in the constipation group changed. Moreover, the other groups exhibited a change in the abundance of Adlercreutzia, Collinsella, Klebsiella, Parabacteroides, and Sutterella. PCA analysis also revealed obvious differences in the regulatory effect of the probiotics among different gut microbial populations and that the probiotics had different effects in improving and treating different intestinal diseases. In addition, Bacteroides and Odoribacter in the constipation group tended to decrease to normal levels. Heatmap analysis showed that several key functional fungi, such as Akkermansia muciniphila, Bacteroides fragilis and Faecalibacterium prausnitzii, were found to appear only at some stages, but disappear after the intervention was withdrawn. At this time, the original Bacteroides ovatus began to decrease. The appearance of these bacteria was beneficial to host health. In summary, probiotic intervention can play a role in altering the diversity and abundance of gut microbes and inhibit the growth of harmful microorganisms in the gut. More importantly, the appearance of beneficial bacteria manifests the physiological effectiveness of the probiotics. Therefore, the probiotics have promising applications in maintaining a healthy state of intestinal microflora.

Herein, we investigated the protective effects of tocopheryl (VE), α-tocopheryl succinate (α-TOS) and tocopheryl polyethylene glycol 1000 succinate (TPGS) on free radical-induced oxidative damage to protein, lipid and DNA, as well as the inhibitory effect on the proliferation of human HepG2 hepatoma cells. The results showed that TPGS had the most protective effect on oxidative damage to biological macromolecules, followed by α-TOS and VE. Both α-TOS and TPGS could significantly decrease cell viability (P < 0.05), and TPGS was more effective. However, VE showed little effect on cell activity (P ﹥ 0.05). This could be due to the amphipathicity of TPGS, whose hydrophobic ends are adsorbed on the surface of biological macromolecules, while the hydrophilic ends are fully extended in the buffer, causing large steric hindrance to protect the biological macromolecules from being attacked by free radicals. Because of its good water solubility, TPGS could easily pass through the biofilm, increasing its effective concentration in HepG2 cells. This work will provide a theoretical basis for the application of tocopheryl derivatives in healthy nutritious foods and pharmaceuticals.

In recent years, antioxidant peptides with high safety and potent antioxidant capacity have become a hot research field. The aim of this study was to investigate the antioxidant and anti-inflammatory effects of a bioactive peptide derived from egg white proteins, WNWAD (Trp-Asn-Trp-Ala-Asp), and its separations WNW (Trp-Asn-Trp), WAD (Trp-Ala-Asp), WN (Trp-Asn) and AD (Ala-Asp). The protective effect against oxidative stress induced by H2O2 in HEK293 cells was evaluated and the in vitro antioxidant activity was measured by 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay. The impact of WNWAD on the cellular content of oxidized glutathione (GSSG) was tested and its effect on the levels of interleukin-8 (IL-8) and tumor necrosis factor (TNF) was assessed by using commercial enzyme-linked immunosorbent assay kits. The results showed that WNWAD at 40 μmol/L possessed the strongest ABTS radical scavenging capacity with a Trolox equivalent antioxidant capacity (TEAC) value of (98.411 ± 0.020）μmol TE/L, followed by WN, WNW and WAD, whose TEAC values were (96.629 ± 0.008), (94.978 ± 0.003) and (88.807 ± 0.003) μmol TE/L, respectively, while AD had no ABTS radical scavenging potential. The survival rate of the cells was (50.240 ± 0.505)% at a H2O2 concentration of 400 μmol/L, with a statistically significant difference (P < 0.001). All peptides concentration dependently protected HEK293 cells from H2O2-induced oxidative damage. Among these, WNWAD had the strongest cytoprotective activity and the cell survival rate was up to 99.12% at 30 μmol/L. Moreover, WNWAD pronouncedly decrease the cellular GSSG content and lowered the levels of IL-8 and TNF. The results above demonstrated that WNWAD played an important role in reducing oxidative stress in HEK293 cells, enhancing cellular antioxidant activity and resisting inflammations.

Objective: Pyrazinamide (PZA), an important first-line drug for tuberculosis, can cause liver injury and intestinal flora disorder in patients. In this study, we intended to explore the effect of dietary probiotic (Lactobacillus casei, LcS) supplementation on PZA-induced liver injury and intestinal flora disorder in rats. Methods: A total of 40 adult male SD rats were randomly divided into 4 groups: normal control group (NC), PZA group (L0), low-dose LcS group (L1) and highdose LcS group (L2). Liver injury was induced in rats in the L0, L1 and L2 groups, and those in the L1 and L2 groups were subjected to LcS (108 CFU/mL) intervention at a dose of 10 and 20 mL/(kg·d) by gavage daily for 10 consecutive weeks. Hematoxylin-eosin (HE) staining was used to observe the pathological changes of liver tissues in rats. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were detected. Quantitative analysis of Bifidobacteria, Lactobacillus and Escherichia coli in rat feces was conducted by real-time fluorescence quantitative polymerase chain reaction (qPCR) based on 16S rDNA V3 variable region. Results: After 10 weeks of treatment with pyrazinamide, HE staining of liver tissues revealed that liver cells showed moderate edema and marked ballooning degeneration with the disappearance of hepatic cord accompanied by the occurrence of inflammatory cell infiltration. The pathological score was 3.20 points, and serum ALT and AST levels were significantly increased to 95.90 and 188.60 U/L compared with those in the control group (73.90 and 139.20 U/L), suggesting successful establishment of the liver injury model. After LcS intervention at different doses for 10 weeks, examination of liver tissue sections showed the structure of hepatic lobules was obviously improved compared with the PZA group and pathological score as well as serum ALT and AST levels were reduced to normal. The quantities of 3 representative intestinal strains were statistically different between different groups and changed with prolonged intervention time. At the end of the sixth and the tenth week of intervention, the amounts of Bifidobacteria and Lactobacillus in the high-dose LcS group were significantly increased compared with the PZA group, while the number of Escherichia coli was significantly decreased (P < 0.05). At the end of the tenth week, the amounts of Bifidobacteria and Lactobacillus in the high-dose LcS group were significantly increased by 1.18 and 1.03 times compared with those before intervention, respectively. Conclusions: LcS time- and dose-dependently has a protective effect on liver injury and intestinal flora disturbance induced by pyrazinamide. The underlying mechanism may be related to the maintenance of intestinal homeostasis and the modulation of the intestinal microbiota in the presence of LcS.

Food allergy is an important public health issue in industrial countries due to the increasing prevalence and the potential life-threatening consequence. The understanding of food allergy mechanisms usually comes from experimental mouse models, which are broadly divided into two categories: oral sensitization model and topical or epicutaneous sensitization model. However, few studies have been focused on the difference between the two categories and the selection of the appropriate one. In this study, we aimed to develop a suitable route for tropomyosin administration by comparing the allergenicity of oral gavage and intraperitoneal injection in BALB/c mice in order to establish an effective animal model and to investigate the underlying mechanisms at the molecular and immunological levels, which will provide a theoretical basis for the establishment of animal model for food allergen research, the exploration of the mechanism of food allergen sensitization, and the prevention and treatment of food allergy. Results indicated that higher tropomyosin-specific immunoglobulin (Ig) E, histamine, and helper T cell (Th) type 2 cytokines were observed in intraperitoneally sensitized mice than those intragastrically sensitized, indicating that intraperitoneal injection was more sensitive in inducing systemic food allergy. Furthermore, higher levels of serum tropomyosin-specific IgG2a and interferon gamma, as well as regulatory T cell population were observed in intragastrically sensitized mice, suggesting that oral gavage may still develop oral tolerance to decrease the allergenicity of shrimp tropomyosin in BALB/c mice in spite of the presence of mucosal adjuvant. This experiment showed that intraperitoneal injection of tropomyosin to sensitized mice is easier than oral gavage, breaking the Th1/Th2 balance and making Th2 response dominant. Accordingly, intraperitoneal injection is more suitable to establish an animal model for food allergy research.

The aim of this paper is to explore the hepatoprotective effect of Herba Cistanchis against alcohol-induced chronic hepatic injury and its underlying mechanism. Phenylethanoid glycosides (PhGs) were extracted and purified from Cistanche deserticola. Then, the PhGs composition was analyzed and the antioxidant activity was determined. The hepatoprotective activity was studied both in vitro and in vivo. In vitro, the survival of HepG2 cells was promoted by PhGs. In vivo, PhGs restored the alterations induced by alcohol, including serological indexes (alanine aminotransaminase, aspartate aminotransferase, γ-glutamyltranspeptidase, acid phosphatase, triglyceride and low density lipoprotein-cholesterol) and hepatic indicators (superoxide dismutase, glutathione S-transferase, glutathione, glutathione peroxidase, malondialdehyde and triglyceride) levels. The prominent microvesicular steatosis and necrosis in hepatic histopathology of model animals were also notably attenuated by PhGs administration. These results indicated that PhGs possess hepatoprotective properties against chronic alcohol-induced liver injury, the mechanisms involve the modulation of related enzyme (including superoxide dismutase, glutathione S-transferase, glutathione peroxidase) activities and the reduction of lipid peroxidation products such as malondialdehyde.

The effects of lactoferrin from bovine whey (LFW), lactoferrin from bovine colostrum (LFC), human lactoferrin (LFH), human lactoferricin (LfcinH) and bovine lactoferricin (LfcinB) on the proliferation of spleen lymphocytes from mice were studied, and different lactoferrin (LF) and lactoferricin (Lfcin) were compared. The cell counting kit-8 assay was used to measure cell proliferation after 24, 48 and 72 h of culture. Moreover, the effects of different LF and Lfcin combined with mitogen on the proliferation of mouse T and B lymphocytes were also evaluated. The results showed that both LF and Lfcin had the most significant effect in promoting the proliferation of spleen lymphocytes at 48 h, which was concentration-dependent in a certain range. Both LF and LFcin enhanced T lymphocyte proliferation induced by concanavalin A and B lymphocyte proliferation induced by lipopolysaccharide in a certain concentration range. These findings indicated that the two types of bovine lactoferrins (LFB) as well as Lfcin can substitute LFH in infant formula products to enhance immune function in infants and young children, and the recommended concentration for LFB and Lfcin was 0.50–2.00 mg/mL and 75–125 μg/mL, respectively.

Objective: To investigate the antidiabetic effect of Lactobacillus plantarum C88 in a type 2 diabetic rat model. Methods: Type 2 diabetes was induced in rats by feeding high-fat diet followed by single intraperitoneal injection of streptozotocin. The diabetic rats were intragastrically administrated with L. plantarum C88 for 28 consecutive days, and then the fasting blood-glucose, glucose tolerance, blood lipids, insulin, inflammatory factors, intestinal barrier function and intestinal flora were measured. Western blot was used to analyze the expression of nuclear factor-κB (NF-κB), tumor necrosis factor-α (TNF-α), zonula occludens-1 (ZO-1), occludin and claudin-1. Results: L. plantarum C88 could effectively improve hyperglycemia and lipid metabolism disorder in type 2 diabetic rats and significantly decrease the levels of TNF-α, interleukine-6, C-reactive protein, lipopolysaccharide, D-lactic acid and other inflammatory factors in the serum. L. plantarum C88 could promote the secretion of insulin, increase glucagon-like peptide-2 level and decrease diamine oxidase and zonulin. In addition, this strain significantly down-regulated the expression of inflammation-associated protein (NF-κB and TNF-α) in the liver and up-regulated the expression of ZO-1, occludin and claudin-1, associated with intestinal permeability in the ileum. Conclusion: L. plantarum C88 is a probiotic with hypoglycemic activity.

The aim of the present study was to investigate the immunomodulatory effect of low-molecular-mass selenoaminopolysaccharide (LSA) in RAW264.7 cells. The effects of LSA and sodium selenite (Se) on the proliferation of RAW264.7 cells were detected by MTT assay. Neutral red test was used to investigate the effect of LSA on phagocytosis and cell morphology in RAW264.7 cells. Enzyme-linked immunoabsorbent assay and real-time fluorescent quantitative reverse transcription-polymerase chain reaction were used to explore the effects of different selenium concentrations of LSA on the secretion and mRNA expression of cytokines (tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-10) in RAW264.7 cells. The results revealed that LSA did not affect cell viability at selenium concentrations between 100 and 1000 μg/L. Sodium selenite significantly inhibited cell viability at selenium concentrations more than 200 μg/L. LSA contributed significantly to phagocytic activity in RAW264.7 cells. In addition, LSA could significantly increase the secretion and gene expression levels of TNF-α, IL-6 and IL-10 in RAW264.7 cells. Taken together, these findings suggested that LSA has immunomodulatory activity on macrophage cell line RAW264.7.

Objective: To investigate the effect of anthocyanins from the fruits of Lonicera caerulea (LCA) on the gene expression of low density lipoprotein receptor (LDLR), ATP-binding cassette transporter G1 (ABCG1), and ATP-binding cassette transporter A1 (ABCA1) in hyperlipidemic rat liver. Methods: A total of 60 male Wistar rats aged two months were randomly divided into 6 groups: normal diet control (ND, intragastrically administered with 1.2 g/(kg·d mb) of physiological saline), high-fat diet control (HFD, similarly administered with 1.2 g/(kg·d mb) of physiological saline), positive control (intragastrically administered with 10 mg/(kg·d mb) of simvastatin tablets), and low-, middle- and high-dose LCA (at 4.0, 40.0 and 120.0 mg/(kg·d mb) groups. The administration lasted for 28 days. At the end of this period, the levels of serum total cholesterol (TC) and triglyceride (TG), HDL cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), apolipoprotein A (Apo-A) and apolipoprotein B (Apo-B) were determined. The mRNA expression levels of LDLR, ABCA1 and ABCG1 were detected by real-time polymerase chain reaction (RT-PCR) and the protein level of LDLR was evaluated by Western blot analysis. Results: Compared with the hyperlipemia model group, LCA could reduce the serum levels of TC, TG, LDL-C and Apo-B and increase the levels of HDL-C and Apo-A (P < 0.05 or P < 0.01). The expression of LDLR protein and mRNA in all dose groups increased significantly (P < 0.05), and the expression levels of ABCA1 and ABCG1 mRNA similarly rose; in particular, a significant increase was observed in the middle- and high-dose groups (P < 0.05). Conclusion: 40.0 mg/(kg·d mb) Lonicera caerulea anthocyanins have a significant role in regulating blood lipids by up-regulating the expression of LDLR and ABC family genes in the liver and consequently regulating reverse cholesterol transportation in hyperlipidemic rats.

In this paper, the antioxidant activities in vitro of polysaccharides (MEMP) and zinc-containing polysaccharides (MEMZP) from Morchella esculenta mycelium cultured in liquid PDA medium with and without added zinc were studied using the Fenton method, the pyrogallol self-oxidation method and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging method. Moreover, in order to evaluate the antioxidant activities in vivo, aging mice induced by intraperitoneal injection of D-galactose (100 mg/(kg·d)) served as control and aging mice treated with MEMP and MEMZP (320 mg/(kg·d)) as treatment groups. The activities of superoxide dismutase (SOD) and catalase (CAT) and malondialdehyde (MDA) content were measured in liver, kidney and serum after 30 consecutive days of administration. The half maximal inhibitory concentration (IC50) values of MEMP and MEMZP were 0.56 and 0.36 mg/mL for scavenging of hydroxyl radical, 0.62 and 0.46 mg/mL for scavenging of superoxide anion radical, and 0.68 and 0.58 mg/mL for scavenging of DPPH radical, respectively. MEMZP could improve SOD and CAT activities (by 9.32% and 36.73%) in the liver of aging mice, decrease significantly MDA content (by 90.71%) (P < 0.05) when compared with MEMP. The antioxidant activities of MEMZP were higher than those of MEMP in a dose-dependent manner in a certain dose range.

Objective: To explore the effects of Pseudobulbus cremastrae seu pleiones polysaccharide (PCSPP) on the regulation of immune functionand the inhibition of tumor growth in sarcoma S180 tumor-bearing mice. Methods: Lymphocyte proliferation capacity and the phagocytic activity of spleen macrophages were determined by 3-(4,5-dimethyl- 2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide and neutral red methods; the effects of PCSPP on tumor growth, spleen index and thymus index in S180 tumor-bearing mice were evaluated through tumor suppression test in vivo, and the effects on T lymphocyte subgroup and serum cytokine levels were detected by flow cytometry and enzymelinked immunosorbent assay, respectively. Results: PCSPP could enhance lymphocyte proliferation capacity and macrophage phagocytic activity. PCSPP could inhibit tumor growth and increase spleen index and thymus index in S180 tumor-bearing mice; meanwhile, it could also increase the levels of CD4+ and CD8+ T cells in mice and elevate the CD4+/CD8+ ratio, interleukin-2, tumor necrosis factor-α and interferon-γ levels. Conclusion: PCSPP has a potent antitumor effect and its inhibitory effect may be related to ithe improvement of immune function.

In the present study, the effect of tilapia skin hydrolysates (TSCH) produced with neutral enzyme (NE), alkaline enzyme and pancreatin enzyme on the growth of human skin keratinocyte HaCaT cells was investigated as well as the relationship between antioxidant capacity and cell growth stimulation of TSCH. Results showed that neutral enzymatic hydrolysate (NEH) had significant antioxidant capacity in vitro and cell growth-promoting effect (P < 0.05). When treated by NEH (1–5 ku) at 25 mg/mL, the proliferation of HaCaT cells was most significantly promoted when compared with other hydrolysates (P < 0.05), and NEH also could promote cell scratch healing ((81.10 ± 5.77)%) after treatment for 24 h. Two major peptide components (1–5 ku) were detected from NEH by Sephadex G-25 gel ?ltration chromatography and amino acid composition analysis. The contents of antioxidant amino acids such as phenylalanine, leucine, tyrosine, lysine, arginine and histidine in NEH 1–5 ku were much higher than those in other molecular mass amino acid residues (P < 0.05). The study suggests that the growth-promoting effect of NEH from tilapia skin collagen on HaCaT cells may be related to the significant amount of antioxidant amino acid residues in the peptides.

The protective effect of Actinidia arguta flavonoids (AAF) on H2O2-induced oxidative injury in human immortalized epidermal cells (HaCaT) was investigated in this study. The flavonoids were extracted from A. arguta grown in DaWei Mountain, Liuyang, Hunan provice. HaCaT cells were cultured in vitro. The experiment was divided into control, hydrogen peroxide damage, positive control (VC), and AAF treatment groups (at concentrations of 0.1–1.0 mg/mL). Superoxide dismutase (SOD) activity and reactive oxygen species (ROS) levels in cells were measured to evaluate the cytoprotective effect of AAF. VC was used as a positive control to evaluate its antioxidant activity. The results showed that at a H2O2 concentration of 30 μmol/L, the survival rate of the cells was approximately 40% and the oxidative damage model was established. When AAF at concentrations of 0.3 and 0.6 mg/mL was used to protect the cells, the survival rate was about 60%, which increased by about 20% compared with the model group. SOD activity (6.33 U/mg) in the treatment group (0.3 mg/mL) was about 2 times higher than that in the model group, with a significant difference (P < 0.05). ROS level decreased significantly by 13% when compared with the model group (677.80). These data suggested a protective effect of AAF on H2O2-indued oxidative damage. Therefore, it can be further developed into a potent natural antioxidant product.

In this study, the effect of chicoric acid on oxidative lipid and DNA damage induced by reactive oxygen species was investigated using Cu2+/H2O2 and 2,2’-azobis(2-amidinopropane)dihydrochloride (AAPH) systems. Mouse liver and brain homogenate, herring sperm DNA and pBR322 DNA were selected as lipid and DNA damage model, respectively. The thiobarbituric acid method was used to evaluate the levels of lipid and herring sperm DNA oxidative damage. The degree of oxidative damage of pBR322 DNA was determined by agarose gel electrophoresis. Results showed that chicoric acid exhibited significant protective effects on lipid and DNA in Cu2+/H2O2 system in a certain concentration range. However, the protective effect of chicoric acid on lipid and DNA was abated at high concentrations. Chicoric acid at 100 μmol/L even showed prooxidant activity on pBR322 DNA. In AAPH system, chicoric acid protected lipid and DNA effectively within the experimental concentration range. In conclusion, chicoric acid has a pronounced protective effect on lipid and DNA, whereas chicoric acid at high concentrations aggravates oxidative lipid and DNA damage induced by hydroxyl free radicals.

This study was designed to investigate the effect of collagen peptides (CPs) on calcium absorption in mice. The animals were randomly divided into normal control group, low calcium model group, calcium carbonate (CaCO3) group, low- (500 mg/kg mb + CaCO3) and high-dose (1 000 mg/kg mb + CaCO3) CPs treatment groups and casein phosphopeptides (CPPs) control group. After 6 weeks of oral administration, the serum levels of calcium, phosphorus and alkaline phosphatase (ALP), calcium absorption rate, bone indices, bone microstructure and trabecular bone morphological changes were measured. The results showed that ALP activity of the CPs treatment groups was significantly lower than that of the low calcium model group (P < 0.05), while bone length, dry mass index, bone calcium content, bone mineral density (BMD), and bone mineral content (BMC) were significantly higher (P < 0.05). CPs at low dose could reverse almost all indexes of the low calcium model group to normal. We observed a significant decrease in ALP activity and a significant increase in bone calcium content, BMD and BMC for the low dose CPs group compared with the CaCO3 group (P < 0.05), suggesting that supplementation of both calcium carbonate and CPs could promote calcium absorption and improve bone microstructure and trabecular morphology. Therefore, CPs could increase calcium absorption rate by increasing the number and intensity of trabecular bone and promoting bone growth.

In order to extend the shelf life of fresh-cut broccoli, four packaging materials: polyvinylidene chloride (PVDC), polyethylene (PE), low-density PE and polymethylpenten were studied for their effects on quality changes during storage. The results showed that the quality of fresh-cut broccoli declined during storage. The highest levels of VC, soluble solids and peroxidase activity and the lowest levels of percentage mass loss, respiration intensity, malondialdehyde content and polyphenol oxidase activity were recorded after 12 days of storage in PVDC film. However, PVDC was not as effective as PE in maintaining chlorophyll content and increasing superoxide dismutase activity. Overall, we concluded that fresh-cut broccoli packaged in PVDC film maintained the best quality during the first 9 days of storage while the samples packaged in PE film showed the highest marketable fruit percentage from the ninth to the twelfth day.

The purpose of this work was to study the effects of different packaging materials on some quality properties of strawberry pulp during storage. After packaging and pasteurization, strawberry pulp from the cultivar ‘Hongjia’ were stored at either 4 or 25 ℃. Three packaging treatments, namely glass bottle, polyvinyl chloride (PVC) bag and aluminum foil bag were comparatively evaluated. Changes in color, the contents of total soluble solids, titratable acid, anthocyanin and VC and sensory evaluation were measured during storage. Results indicated that when stored at 4 ℃ for 30 days, the anthocyanin content of strawberry pulp in glass bottle was 82.29 mg/100 g, which was 1.08 and 1.27 times as high as that stored in PVC bag and aluminum foil bag, respectively. The a* value of strawberry pulp in glass bottle packaging was 15.12, which was much higher than that of aluminum foil bag packaging (12.25). Compared to the other packaging treatments, glass bottle showed more advantages in oxygen barrier capacity and preserving the quality of strawberry pulp during storage under 4 ℃, which could slow down the degradation of anthocyanins and was more suitable for the storage of strawberry pulp. These results provide a basis for the storage of strawberry pulp.

Apple contains a variety of functional phenolic substances, but no systematic studies have been conducted to investigate their variation during shelf life after harvest. In this paper, ‘Jonagold’ apples were treated with 1-methylcyclopropene (1-MCP) and then stored at (0 ± 1) ℃ for 3 months with the aim of investigating the effect of 1-MCP treatment on the contents of 5 individual phenolic compounds in apple flesh and peel. The results obtained were as follows. The most abundant phenolic compound in the peel was hyperoside, whereas chlorogenic acid was the most abundant phenolic compound in the flesh. During the shelf period, the contents of hyperoside, chlorogenic acid, quercetin, rutin and total phenolics decreased in the fruits, while the level of phloridzin increased. 1-MCP treatment effectively maintained the contents of hyperoside, chlorogenic acid, quercetin, rutin and total phenolics, and inhibited the increase in phloridzin.

In order to investigate the effect of modified atmospheres with varying carbon dioxide levels on the preservation of chilled chicken, chilled chicken was inoculated with 103 CFU/g Pseudomonas fluorescent after sterilization by irradiation, packaged in different modified atmospheres: M1 group ((V(CO2):V(N2) = 20:80), M2 group ((V(CO2):V(N2) = 20:80), M3 group ((V(CO2):V(N2) = 40:60) and M4 group ((V(CO2):V(N2) = 60:40) and then stored at (4 ± 1) ℃. Normal air package was used as control. Changes in the degree of concavity, P. fluorescent count, pH, total volatile basic nitrogen (TVB-N) and putrescine content were measured during storage. Results showed that P. fluorescent count, TVB-N and putrescine content increased with increasing storage time, whereas they decreased with increasing CO2 level. The degree of concavity increased with increasing storage time or CO2 level; the degree of concavity in group M4 was significantly higher than that in other groups (P < 0.05), impacting the visual appearance of chicken. No difference in the degree of concavity or putrescine content was observed comparing groups M2 and M3 (P > 0.05). Similarly, no difference in TVB-N content was found from the ninth day to the twelfth day of storage (P > 0.05). Thus, an identical preservation effect was achieved. However, CO2 is more expensive than N2 of the same volume. Overall, we concluded that modified atmospheres containing 20%–40% of CO2 could strongly inhibit the growth of P. fluorescent in chilled chicken under the storage of (4 ± 1) ℃.

The efficacy of 1-methylcyclopropene (1-MCP) in preserving the quality of early-middle maturing table jujube was investigated in this study. The early-middle maturing variety ‘Yanliangcuizao’ and the early maturing variety ‘Qiyuexian’ were harvested and fumigated with 0.1, 0.5 or 1.0 μL/L 1-MCP for 24 h at (20.0 ± 1.0) ℃, and another early maturing variety ‘Zaocuiwang’ were fumigated with 0.5 or 1.0 μL/L 1-MCP, using air sealed and fumigated fruits as the control. All treated fruits were packaged in needle holed 20 μm thick PE bags and stored at 0–1 ℃ and relative humidity of 70%–80%. Physiological and quality change of the fruits were measured periodically during storage. 1-MCP treatment at 1.0, 0.5 and 1.0 μL/L was found to be optimal for ‘Yanliangcuizao’, ‘Qiyuexian’ and ‘Zaocuiwang’, respectively. Compared with the control, 1-MCP treatment decreased ethylene release and respiration rate of the ‘Yanliangcuizao’, postponed the peak time of the two indexes. 1-MCP delayed the decrease of starch, reducing sugar and soluble sugar, maintained higher ascorbic acid contents, enhanced ascorbate peroxidase, superoxide dismutase and catalase activity, inhibited lipoxygenase activity and reduced malondialdehyde accumulation. In conclusion, 1-MCP retarded senescence in early-middle maturing jujube through resistance to reactive oxygen and reduced respiration rate.

Food species identification is one of the most important aspects in food authenticity assessment. Polymerase chain reaction and gene chip technology have been applied for food species identification. High-throughput sequencingbased metabarcoding technology has developed rapidly in recent years. Compared with the standard Sanger sequencingbased DNA barcoding approach, metabarcoding has shown great advantages in food species identification due to its low cost, high throughput and rapidity for the simultaneous detection of multiple species in complex samples. This review presents the definition of metabarcoding and the methods used in this research field. Then, we summarize the applications and challenges of metabarcoding in food species identification. Finally, we discuss the future direction for the development of metabarcoding.

Fresh beef spoilage is a microecological phenomenon which involves several specific spoilage organisms and is affected by lots of factors. In order to control beef spoilage and to prolong its shelf life, it is important to understand the source and diversity of bacterial contaminants in beef. Therefore, this paper aims to provide a systematic overview of spoilage bacteria in beef from the following aspects: all possible sources of microbial contamination from slaughter to packaging, the species classification and diversity of microbial contaminants, and the mechanism of the spoilage potential of individual genera and mixed bacteria. Overall, the major contamination sources are the fur of living animals and contaminants on it, knives used for dressing and workers’ hands and all contact surfaces during cutting procedure, and the main spoilage bacteria are Pseudomonas spp., Enterobacteriaceae, lactic acid bacteria and Brochothrix thermosphacta. Different species of spoilage bacteria produce different spoilage phenomena due to the difference in the order of metabolism of nutritional substrates. It is expected that this review will provide a powerful theoretical basis for spoilage bacterial control in fresh beef.

In recent years, regulating the sensory and functional properties of foods by taking advantage of the interaction between food components has become a hot research topic in food science. The interaction between polyphenols and starch is widely found in foods, which may endow foods with several unique properties and cause certain functional effects in most cases. This review summarizes the current knowledge of the interaction between polyphenols and starch. The formation mechanism and model of starch-polyphenol complex are demonstrated, and the physicochemical properties and digestibility of starch in the complex system as well as the encapsulation characteristics of polyphenols are discussed. The interaction between starch and polyphenolic compounds can improve starch digestibility and polyphenol bioavailability, which will provides a theoretical basis for the development of novel functional foods for the prevention and control of hyperglycemia.

Unsaturated alkylamides, a class of important pungent and tingling compound present in prickly ash, are mainly composed of α-, β-, γ- and δ-sanshool and their derivatives. These compounds stimulate sensory neurons by activating transient receptor potential (TRP) V1 and TRPA1 or inhibiting two-pore potassium ion channels. The strength of numb taste is affected by the structure of pungent and tingling compounds, which activate different receptors to produce different numb taste intensities due to their different structures. Currently, there are two commonly used methods to prepare pungent substances: conventional extraction by column chromatography and preparative chromatography, and chemical synthesis by appropriate chemical reactions. In this paper, the major types of pungent and tingling compounds in prickly ash are summarized and the current knowledge about the mechanism of the perception of these compounds and the methods for their preparation are reviewed. We hope that this review will provide useful information for the systematic and intensive study of numb-taste substances.

As a renewable green biological resource, starch deserves to be researched and has the potential to be widely applied. However, native starch has limited applications because of its shortcomings in structure and properties. Accordingly, modifying native starch by various methods has become a hot topic among researchers. Although the chemical and enzymatic method are currently commonly used for starch modification, many problems such as low reaction rate, environmental pollution and the complex process have been encountered during their application. This article describes a new method for starch modification, microwave irradiation. Herein, we present a systematic review of the mechanism of action of microwave irradiation on starch and its effect on the structure (granular morphology, crystal structure and chemical bonds), physicochemical properties (solubility, swelling power, pasting properties, thermal properties and digestibility) and safety of starch. The current status and future perspectives of microwave irradiation in starch modification and starchy food processing are discussed.

In recent years, China’s export of vegetable products to the European Union (EU) has been affected by technical measures to trade due to the differences between the methods and standards used for the determination of pesticide residues in China and the EU. In this paper, we analyze China’s export stumble cases, aiming to find the differences in the number of methods used for pesticide residue determination, the technical details of vegetable detection and the quality control of the standard methods between the country and the EU. Our focus is on the differences between the analytical methods used for typical exported vegetable products in China and the EU. Furthermore, we put forward some countermeasures including integrating the current methods and standards, improving the efficiency of sample pretreatment as well as the precision and sensitivity of the methods, and further standardizing the quality control of the methods.

Gynostemma pentaphyllum, a plant of the Cucurbitaceae family, contains saponins, flavonoids, polysaccharides and other bioactive ingredients and has many bioactivities such as inhibiting tumor, reducing blood fat and blood sugar, antiaging, and protecting cells. Gypenoside, a major active ingredient in G. pentaphyllum, has arisen much attention in recent years, because it contains the same mother nucleus of dammarane-type tetracyclic triterpenoids as ginsenoside. In recent years, modification of the glycosidic moiety of gypenoside by bioconversion for derivatives with improved activity has become a research hotspot, and abundant studies on this topic exist in the literature. However, a systematic review is still lacking. In this context, this paper reviews recent advances in research on the structure and classification of gypenosides, the difference and similarity between gypenosides and ginsenosides, and the biotransformation and bioactivity of gypenosides. Finally, directions for future research are put forward. Hopefully, this review will provide insights for gypenosides biotransformation in vitro.

This paper compares various legislative modes for edible agricultural product regulation and analyzes the factors that may lead to failure to achieve the expected effect of the current legislative modes for edible agricultural product regulation when implemented in practice. Herein we propose that the fundamental factor is confusion of edible agricultural products with general agricultural products in the regulating objects, neglecting the particularity of edible agricultural products and leading to difficulty in meeting the requirements of social co-government, strict regulation and product traceability. Meanwhile, when the Agricultural Product Quality Safety Law is merged in isolation into the Food Safety Law, the overlapping of the regulating objects of the two laws may be neglected. In order to enhance regulatory chain integration and improve edible agricultural product quality regulation, this paper recommends that the articles concerning edible agricultural products in the Agricultural Product Quality Safety Law be merged into the Food Safety Law.