This study was conceived in order to clarify the effect of the freshness of raw eggs on the gel quality and the ultrastructure of eggshell membrane during the curing of preserved eggs. Duck eggs with different freshness were used to make preserved eggs in the same way. The ultrastructure of eggshell membrane was observed by scanning electron microscopy (SEM), and Image J software was used to process the image data to obtain eggshell membrane status. Besides, eggshell membrane porosity, and gel pH, water content, hardness and elasticity were measured and the correlation between them was analyzed. The results showed that during the curing process, the pH of preserved egg white decreased first, then slowly increased, and finally decreased sharply; the hardness and elasticity of preserved egg gels showed a fluctuating trend. The lower the freshness of raw eggs, the higher the porosity of eggshell membrane, and the shorter the curing cycle of preserved eggs. The porosity of eggshell membrane had a significantly negative correlation with the freshness of raw eggs (P < 0.01), and a significantly positive correlation with gel hardness (P < 0.01) and elasticity (P < 0.05). As a result, a decrease in the freshness of raw eggs could affect eggshell membrane as the permeation channel for the brine, which could in turn lead to variability in the quality of preserved eggs. Moreover, the yield of preserved eggs decreased with a decrease in the freshness of raw eggs. Therefore, the freshness of raw eggs is closely related to the quality of preserved eggs. This study provides a new idea for controlling the quality change of preserved eggs during the pickling process.

In order to investigate the photodynamic inactivation (PDI) effect of curcumin on Pseudomonas fluorescens and to improve the efficiency of photodynamic sterilization, ethylene diamine tetraacetic acid (EDTA) was used as a synergist to enhance the bactericidal efficacy of curcumin and the PDI conditions were optimized. The PDI effect of curcumin combined with EDTA on P. fluorescens biofilm was investigated. Curcumin combined with EDTA was further applied to the preservation of fresh pork. The results showed that after 20?min of illumination at a power density of 200?mW/cm2 and a wavelength of 460?nm, the total count of P. fluorescens was decreased by 6.40?(lg(CFU/mL)) by treatment with 0.5% (m/V) EDTA and 75?μmol/L curcumin, and the count of P. fluorescens in the biofilms formed on glass and acrylonitrile-butadiene-styrene (ABS) plates by 4.57 and 6.60?(lg(CFU/mL)), respectively; the effect of the combined treatment was significantly more pronounced than that of curcumin alone (P < 0.05). Fresh pork was treated with 75?μmol/L curcumin and 0.5% EDTA and illuminated at a power density of 100?mW/cm2 and a wavelength of 460?nm for 20?min. On day 10 of storage, the count of P. fluorescens on pork was decreased by 3.05?(lg (CFU/mL)) compared to the untreated control group, and the mass of pork was decreased by 2.14%. The color difference ΔE increased with increasing curcumin concentration. The pH of the treated pork changed slowly during storage. It was indicated that PDI treatment had a slight impact on the sensory quality of pork while maintaining its pH, and significantly inhibited the proliferation of P. fluorescens on it. In conclusion, photodynamic treatment using curcumin combined with EDTA significantly prolongs the shelf life of pork. This study is expected to provide a new theoretical reference and technical support for the application of photodynamic technology in food sterilization and preservation.

This study aimed to clarify the changes in ATPase activity and its effect on the microstructure and water-holding capacity (WHC) of Tan sheep meat during postmortem aging. The Longissimus dorsi muscle of Tan sheep slaughtered at 6 months of age was aged at 4 ℃ and evaluated for the activities of Na+-K+-ATPase, Ca2+-ATPase and caspase-3, microstructure, pH and drip loss rate after 0, 1, 2, 4 and 8 days. Results showed that the activities of Na+-K+-ATPase and Ca2+-ATPase increased initially and subsequently decreased with aging time, peaking at day 1. The activity of caspase-3 and drip loss increased with aging time up to 2 days and then decreased. In contrast, the opposite trend was observed for muscle pH. The contents of total proteins, low-salt soluble proteins, and high-salt soluble proteins continuously decreased with aging time. The content of water soluble proteins significantly decreased after day 2 (P < 0.05). On day 8, the myofibrils were broken, and gaps between myofibers, between muscle fiber bundles, and between myofibers and sarcolemma appeared; the Z lines were broken, and the H bands disappeared. Correlation analysis indicated that the activity of Na+-K+-ATPase was correlated with all other parameters (P < 0.01) and the activity of Ca2+-ATPase was significantly correlated with muscle pH and the activities of Na+-K+-ATPase and caspase-3 (P < 0.01). Overall, during postmortem aging, the variations in the activities of Na+-K+-ATPase and Ca2+-ATPase can lead to downstream caspase-3 activation to hydrolyze cytoskeleton proteins, resulting in the formation of gaps at different muscle sites. The water in muscle flows into the formed gaps due to gravity, causing an increase in the drip loss and a decrease in the WHC of Tan sheep meat.

Based on the traditional tea sensory evaluation method, this study examined the feasibility of the application of quantitative descriptive analysis (QDA) and check-all-that-apply (CATA) in the evaluation of sensory aroma characteristics of large-leaf yellow tea. In the QDA, 10 selected panelists generated descriptors freely, and selected 16 descriptors according to the geometric mean value to established a sensory vocabulary for large-leaf yellow tea with reference samples of different intensities. A total of 18 aroma descriptors and 10 emotion descriptors were designed by CATA, and the vocabulary of the questionnaire was evaluated by 100 consumers recruited. The results showed that CATA and QDA could select similar sensory descriptors and aroma characteristics. QDA had higher accuracy and could distinguish the difference in aroma intensity. CATA was a relatively easy, fast and low-cost method for obtaining differences in aroma characteristics from consumers. In addition, consumer preference test results showed that low-roasting and high-tenderness large-leaf yellow tea was more popular with consumers. This study can provide a reference for large-leaf yellow tea manufacturers and help in making the large-leaf yellow tea consumption market flourish.

In order to explore the molecular mechanism of the response of the antioxidant system in broccoli heads to high O2 stress, the changes in the antioxidant system and related protein expression in broccoli heads under different O2 concentrations (5% O2 + 5% CO2, 20% O2 + 5% CO2 and 40% O2 + 5% CO2) were investigated by physiological and biochemical analysis and isobaric tags for relative and absolute quantitation (iTRAQ) proteomics. The gene ontology (GO) annotation, the clusters of orthologous groups of proteins (COG) analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that a total of 76 differentially expressed proteins related to the antioxidant system were identified in this study, which were involved in the ascorbate-glutathione cycle, glucosinolate degradation, and the metabolism of polyphenols, flavonoids and antioxidant enzymes. The proteomic analysis showed that the 40% O2 + 5% CO2 treatment significantly inhibited the activity of an ascorbate peroxidase and three glutathione peroxidases, thereby inhibiting the ascorbate-glutathione cycle in broccoli compared with the 5% O2 + 5% CO2 treatment. Meanwhile, the 40% O2 + 5% CO2 treatment significantly increased the activities of 16 myrosinases and promoted the degradation of glucosinolate. In addition, the expression of shikimate dehydrogenase in the 40% O2 + 5% CO2 treatment group decreased by 23% compared with that in the 5% O2 + 5% CO2 treatment group, inhibiting shikimic acid synthesis and the accumulation of polyphenols and flavonoids. This study has revealed the cause of rapid yellowing and senescence in broccoli heads under high O2 stress, which provides a theoretical basis for the development of new broccoli preservation technology and the remission of high O2 stress.

The sensory flavor characteristics and characteristic flavor composition of Baijiu are an important basis for recognizing different aroma types of Baijiu and identifying Baijiu quality. However, at present, there are few studies on the sensory quality and flavor compounds of different aroma types of Baijiu. In this study, the major volatile compounds of four aroma types of Baijiu, Jiangxiangxing, Nongxiangxing, Qingxiangxing and Qingjiangxiangxing, were determined by sensory evaluation and headspace-solid phase microextraction/liquid-liquid microextraction coupled to gas chromatography-mass spectrometry (HS-SPME/LLME-GC-MS) and gas chromatography-flame ionization detector (GC-FID), and their characteristic volatile compounds were identified by their odor activity values (OAV). Besides, a correlation evaluation model was developed using partial least squares regression (PLSR). The results showed that there were significant differences in the flavor profiles of the aroma types of Baijiu. A total of 251 volatile compounds were detected across all samples, including 54 characteristic flavor compounds. Ethyl isovalerate, dimethyl trisulfide, ethyl butyrate, furfural, 2,3,5-trimethylpyrazine, 2,3,5,6-tetramethylpyrazine contributed significantly to the flavor of Jiangxiangxing Baijiu. The key flavor compounds of Nongxiangxing Baijiu were ethyl hexanoate, p-cresol and γ-nonolactone. Nonanal, ethyl decanoate and phenylethanol were the characteristic flavor compounds in Qingxiangxing Baijiu. The most significant contributors to the characteristic flavor of Qingjiangxiangxing Baijiu were dimethyl trisulfide, phenethyl acetate, phenethyl alcohol, nonanal, decanal, ethyl laurate and 3-methyl-1-butanol.

This study aimed to prepare an inclusion complex ferulic acid (FA) with 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) and evaluate its effects on the pH, growth, gene expression, and tyramine accumulation in the cultured broth of Enterobacter cloacae L63 and tyramine accumulation in smoked horsemeat sausage inoculated with this strain. Real time-quantitative polymerase chain reaction (qPCR) was used to measure the expression of the tyrosine decarboxylase (tdcA), tyrosine/tyramine antiporter (tyrP), tyrosine t-RNA synthetases (tyrS) and Na+/H+ antiporter (nhaC) genes in the tyramine-producing pathway. In addition, high performance liquid chromatography (HPLC) was employed to detect tyramine accumulation during 48 h of culture of Enterobacter cloacae L63. The results showed that FA and its inclusion complex with HP-β-CD reduced the expression of tdcA and tyrP (P < 0.05), had a strong antibacterial activity against E. cloacae L63, inhibited the increase in the pH of the cultured broth and smoked horsemeat sausage and reduced tyramine accumulation. The inclusion complex was more effective against tyramine accumulation (P < 0.05).

In order to realize quality monitoring and spoilage early warning of tomatoes during storage based on three-dimensional (3D) fluorescence information of the storage room gas, a strategy for selecting feature wavelengths based on wavelet packet decomposition was proposed. Firstly, Rayleigh scattering removal and Savitzky-Golay (SG) smoothing were carried out on the original data to eliminate the noise interference and the background emission spectrum without fluorescence information. Secondly, the emission spectrum corresponding to each excitation wavelength was decomposed by the wavelet packet method and the feature excitation wavelengths were selected by the energy of the lowest frequency band combined with its proportion in the total energy. Thirdly, the emission spectrum corresponding to each selected feature excitation wavelength was divided into different bands, each band was decomposed by the wavelet packet method, and the feature emission wavelengths were selected by the lowest wavelet packet frequency band energy. Fourthly, considering the different fluorescence information of tomatoes before and after spoilage, the benchmark of tomato spoilage could be determined by the total energy change of the feature excitation wavelengths; at the same time, the same benchmark was obtained by cluster analysis of spectral vectors at the feature emission wavelengths. Fifthly, the feature emission wavelengths were optimized according to the spoilage benchmark to reduce the number of the feature wavelengths and simplify the analysis. Finally, the feature emission wavelengths of the spoilage benchmark date were taken as the benchmark vector to calculate the Mahalanobis distance between it and fluorescence feature vectors before the benchmark date. The results showed that with the advance of storage, the Mahalanobis distance decreased, effectively describing the quality change of tomatoes during storage and ultimately realizing spoilage early warning.

This study focused on evaluating the antibacterial activity of essential oils from Zanthoxylum schinifolium Siebold & Zucc. (ZSEOs) against Streptococcus mutans, Streptococcus sanguinis, and Streptococcus sobrinus. The essential oils were extracted from the pericarp of Z. schinifolium produced in four different areas of China (Chongqing, Guizhou, Sichuan, and Yunnan) by steam distillation and were designated as ZS1EO, ZS2EO, ZS3EO and ZS4EO, respectively and their chemical compositions were determined by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOFMS). Meanwhile, the diameter of inhibition zone, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and growth curve of the cariogenic bacteria were measured to evaluate the antibacterial activity of ZSEOs. In addition, morphological changes in cariogenic bacteria after treatment with ZSEOs were determined by scanning electron microscopy (SEM). The results indicated that linalool (18.86%–22.00%), limonene (9.56%–14.84%), β-myrcene (5.79%–12.70%), sabinene (5.49%–8.93%) and β-pinene (3.33%–6.41%) were identified as the main components of the four ZSEOs. All ZSEOs showed inhibitory activity against the growth of S. mutans, S. sanguinis, and S. sobrinus, among which ZS1EO had the most potent antibacterial activity. The MIC and MBC of ZS1EO against the three cariogenic bacteria were 0.5–1.0 and 1–2 mg/mL, respectively. The growth of bacterial cells in the lag and exponential growth phases was stopped by treatment with ZS1EO at MIC concentration. The antibacterial activity of ZS1EO was related to the destruction of the bacterial chain structure and bacterial cell membrane damage. Collectively, this study highlights the potential used of ZSEOs as plant-derived anticariogenic agents.

This study aimed to explore the changes in the phenolic content and antioxidant activity of black hulless barley processed by different methods after in vitro gastrointestinal digestion. The tested methods included boiling, stir frying, extrusion puffing, explosion puffing and fermentation. After digestion, the phenolic content of the five processed samples increased 1.99–2.44 folds (P < 0.05). The total flavonoid content of all processed samples except the one subjected to explosion puffing decreased by 34%–70% (P < 0.05). Phloretin, protocatechin, p-coumaric acid and ferulic acid were the major phenolic acids, and catechins were the major flavonoids after in vitro gastrointestinal digestion. Meanwhile, the contents of the major monomeric phenolic acids in the five processed samples significantly increased (P < 0.05), whereas the contents of the monomeric flavonoids significantly declined (P < 0.05). The antioxidant potency composite (APC) indexes of the processed samples declined in the following order: extrusion puffing (89.61%), fermentation (88.16%), boiling (77.67%), explosion puffing (76.86%) and stir frying (75.13%). In conclusion, the contents of total phenols and total flavonoids were the highest in black hulless barley subjected to explosion puffing, while the sample subjected to extrusion puffing had the highest antioxidant activity. This study can provide a scientific guideline for selecting different processing methods for the development of hulless barley products to meet diverse consumer demands.

Postmortem ovine Longissimus dorsi muscle was treated by dielectric barrier discharge (DBD) low-temperature plasma with different intensities (0, 30, 60, 90 and 120 s) and then stored 4 ℃. The changes in the pH, color, juice loss, shear force, total bacterial count and protein oxidation indicators of the samples during storage were analyzed to explore the effect of DBD low-temperature plasma treatment on the quality of lamb meat. The results showed that during storage, the pH of the treated samples was lower than that of the untreated ones. The L* and b* values of the samples increased firstly and then decreased with treatment time. DBD low-temperature plasma treatment had no significant influence on the color or shear force, but could accelerate protein oxidation in lamb meat. Furthermore, this treatment significantly (P < 0.05) reduced the total count of bacteria during storage. After five days of storage, the total count of bacteria in the control group was 6.10 (lg (CFU/g)), which was far beyond the limit. However, the total count of bacteria the treatment group exceeded the limit value after seven days, indicating that DBD low-temperature plasma treatment can extend the shelf life of lamb meat. DBD low-temperature plasma treatment for 60 s had the least negative impact on lamb meat quality during storage.

The effect of ultrasonic (US) pretreatment time (0, 10, 20, 30 min) on the drying kinetics and quality attributes of heat pump-dried scallop adductors were investigated to enhance the drying efficiency and improve the product quality. Low-field nuclear magnetic resonance (LF-NMR) spectroscopy was used to explore the water state and distribution of scallop adductors during the drying process. The results showed that the drying process took place in the falling rate period and was controlled by internal moisture diffusion. The drying rate and the effective moisture diffusion coefficient were increased by US pretreatment. Compared with the untreated control group, US pretreatment reduced the total color difference and improved the toughness of dried scallop adductors. The fitting results of the drying mathematical model showed that Midilli et al. model is the most suitable model for describing the drying process. LF-NMR spectra revealed that immobilized water determined the change in the water content of scallop adductors during the drying process. The migration rate of free and immobilized water was increased with increasing US time. The relaxation time of immobilized water T22 had a strong correlation with the moisture content. We concluded that US pretreatment increases the drying efficiency and affects the color, shrinkage rate, rehydrate rate and texture properties of dried scallop adductors. LF-NMR spectroscopy can be employed to predict the change in the moisture content of scallop adductors during the drying process. This study provides a theoretical basis and practical reference for the heat pump drying of aquatic products, especially scallop adductors.

‘Marselan’ (Vitis vinifera L.) grape berries were used to investigate the effect of flash vacuum expansion on monomeric phenolics and CIELab color parameters during wine fermentation and maturation. The results showed that compared to the control group (maceration-fermentation), flash vacuum expansion increased the concentration of most monomeric anthocyanins during fermentation, but was not favorable to maintain the concentration of monomeric anthocyanins during aging. Flash vacuum expansion increased the concentrations of non-anthocyanin monomeric phenolics such as quercetin-3-O-glucoside, catechins, trans-resveratrol, and resveratro-3-O-β-D-glucoside, but decreased the concentrations of quercetin, myricetin, phenolic acids, cis-resveratrol, and piceatannol during wine fermentation and maturation. Flash vacuum expansion reduced the color parameters brightness (L*), yellowness-blueness (b*) and hue angle (hab) values, but significantly increased redness-greenness (a*) and chroma (Cab*) vales, which made the wine’s color redder, darker and more stable. There was a significant color difference between the two groups. In conclusion, flash vacuum expansion can increase the total amount of monomeric phenolics and the color stability of ‘Marselan’ wine.

Konjac glucomannan (KGM) gel was frozen by air freezing, immersion freezing and ultrasonic-assisted freezing, separately and analyzed for changes in its properties and structure by a texture analyzer, an X-ray diffractometer (XRD), low field nuclear magnetic resonance (NMR) spectroscopy, differential scanning calorimetry (DSC), and cold field scanning electron microscopy (SEM). The results showed that compared with air freezing and immersion freezing, ultrasonic-assisted freezing increased the cooling rate of the gel, reduced the syneresis rate, and increased the gel strength without changing the crystallinity of KGM. When the ultrasonic power was 300 W, the syneresis rate and strength of the gel reached their best level. Compared with air freezing, ultrasonic-assisted freezing reduced the syneresis rate by 23.56% and increased the gel strength by 61.23%. The DSC heat flow curves showed that ultrasonic-assisted freezing increased the eutectic point of the gel and lowered its thawing temperature. The microscopic images showed that the network structure of the gel frozen at an ultrasonic power of 300 W was the densest, with the smallest pores. In conclusion, 300 W ultrasonic-assisted freezing can effectively improve the gel characteristics of KGM, which provides a theoretical foundation for the production of new KGM gel foods.

Objective: A mouse model of celiac disease induced by gluten was established and its feasibility was evaluated by testing diagnostic indicators of celiac disease. Methods: Female BALB/c mice aged 6–8 weeks fed a gluten-free diet for more than three generations were randomly divided into two groups, control and celiac disease (CeD). On the first day of the experiment, the mice in the CeD group were fed a gluten-containing diet (2.5 g/kg) instead of the gluten-free diet for 30 days while those in the control group were still fed the gluten-free diet. In the first three weeks, each mouse in the CeD group was intraperitoneally injected with 0.2 mL of 0.01 mol/L phosphate buffered saline containing 150 μg of gliadin twice a week. In the fourth week, the rear footpad of each mouse in this group was injected twice with 50 μg of gliadin emulsified in 50 μL of Freund’s complete adjuvant (on the first and fourth days respectively). Fluorescein isothiocyanate-labeled dextran levels were used to indicate intestinal permeability in mice; real-time quantitative polymerase chain reaction (qPCR) was used to detect the expression of tight junction proteins (ZO-1, ZO-2 and claudin-1), inflammatory cytokines (interleukin (IL)-15, IFN-γ and IL-4) and immune cell marker genes (CD4, CD19 and CD138) in the duodenum; and the enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of total transglutaminase (tTG) and zonulin in duodenal tissue. Results: The intestinal barrier of the mice in the CeD group was damaged, the length of small intestinal villi was significantly decreased, the mRNA expression of the gene encoding transglutaminase 2 (TG2) was significantly increased (P < 0.05), and the relative expression levels of genes encoding cytokines and immune cell markers associated with celiac disease were notably increased compared with the control group. Conclusion: The animal model can effectively mimic the key clinical features of celiac disease as evidenced by intestinal pathology, intestinal barrier, and immune response. It may be used in future research to develop potential therapeutics for celiac disease.

For high-value utilization of wheat germ, the effects of wheat germ-derived peptide ADWGGPLPH on the viability of osteoblast (OB) and osteoclast (OC) in an H2O2-induced oxidative stress model were investigated in OB-OC co-culture system. Flow cytometry, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and Annexin V-fluorescein isothiocyanate/propidium iodide (FITC/PI) double staining were used to clarify the effects of wheat germ-derived peptide on OB proliferation and apoptosis in oxidative stress environment. The effects of wheat germ-derived peptide on the differentiation of OB and OC in the co-culture system under oxidative stress were determined by using alkaline phosphatase (ALP) activity assay, enzyme-linked immunosorbent assay (ELISA) and tartrate resistant acid phosphatase (TRAP) staining. The results showed that wheat germ-derived peptide effectively prevented the increase of reactive oxygen species (ROS) in OB, and enhanced the ability of OB to protect against and scavenge free radicals by suppressing malondialdehyde (MDA) generation and increasing the activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD). Wheat germ-derived peptide significantly inhibited the apoptosis of OB and improved its proliferation. Annexin V-FITC/PI double staining showed that the apoptosis rate was decreased from 12.4% to 5.3%, and the viability was increased from 60.4% to 92.8% (P < 0.01). In addition, wheat germ-derived peptide prevented the decrease of ALP activity, protein type I collagen (COL-I) and osteocalcin (OCN) expression, and increased OB mineralization from 21.3% to 84.3% (P < 0.01), thus maintaining OB differentiation and ensuring normal bone mineralization. Moreover, TRAP staining results showed that wheat germ-derived peptide effectively inhibited the over-differentiation of OC under oxidative stress condition, decreasing the relative positive area of OC from 376.4% to 128.1% (P < 0.01). In conclusion, this wheat germ-derived peptide has protective effects against H2O2-induced cellular oxidative damage in OB-OC co-culture system, thereby maintaining cellular homeostasis. This finding provides a certain theoretical basis for the development and utilization of wheat germ protein.

Objective: The aim of this study was to explore the effects of polyphenols on the absorption of lutein at different stages through lutein micellization, cell absorption, and in vivo absorption experiments. Methods: The bioavailability and micellar properties of lutein under the action of polyphenols were detected using in vitro simulated digestion. The Caco-2 cell model was constructed to determine the cellular uptake of lutein and the expression of transport proteins such as scavenger receptor class B type I (SR-BI), Niemann-Pick C1L1 (NPC1L1), and CD36 under the action of polyphenols. We also examined changes in the contents of lutein in the liver and plasma of mice with and without the action of polyphenols. Results: The in vitro digestion experiments showed that the bioavailability of lutein was increased by 4.3–8.0 times compared to the control group. Meanwhile, polyphenols reduced the average particle size of the lutein micelle solution and increase the absolute value of the potential and consequently change the performance of lutein micelles. Cell experiment results showed that different polyphenols increased the cell uptake of lutein by 3.2%–30.4%, and also activate the SR-BI, NPC1L1, and CD36-mediated signaling pathways. In addition, polyphenols significantly increased the lutein content in the liver and plasma of mice. Conclusion: Polyphenols can promote the absorption of lutein during the micellization process and absorption in cells and in vivo.

Objective: To investigate the effect of procyanidin B2 on gene expression in the femur of high-fat diet (HFD)-fed mice with calcium metabolism disorders. Methods: Twenty-seven C57BL/6 male mice were randomly divided into three groups: control, HFD, and HFD plus 0.2% procyanidin B2. The body mass, plasma lipid levels, calcium homeostasis, calcium absorption capacity, and bone mineral levels of the mice were measured after eight weeks of feeding, and gene expression in the femur of the mice was determined by using eukaryotic transcriptome sequencing. The results showed that procyanidin B2 significantly reduced plasma lipid and parathyroid hormone levels, significantly increased net calcium absorption and storage capacity (P < 0.05), and ameliorated the reduction in bone mineral, femoral calcium content, and maximum loading capacity in HFD-fed mice. Forty-nine differentially co-expressed genes (DCGs) were identified by high-throughput sequencing, and procyanidin B2 could improve the expression of 48 of these genes. Gene ontology (GO) enrichment analysis showed that these DCGs belonged to the two branches of biological processes and cell components. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that 13 pathways were significantly enriched (P < 0.05). The expression levels of five DCGs, Cdkn2a, Adrb1, Fcgr4, Aldh1a3, and Calml3, involved in the calcium metabolism-related signal transduction and metabolic pathways were significantly changed (P < 0.05). Compared with the HFD group, procyanidin B2 supplementation down-regulated the expression of the Cdkn2a, Adrb1, and Fcgr4 genes by 9.19-, 3.68-, and 3.61-fold, and up-regulated the expression of the Aldh1a3 and Calml3 genes by 2.06- and 3.29-fold, respectively. Conclusion: Procyanidin B2 ameliorates calcium metabolism disorders in HFD-fed mice, which may be associated with the down-regulated expression of genes related to osteoblast activity and up-regulated expression of genes related to osteoclast activity.

To investigate the pathogenicity of viable but non-cultivable state (VBNC) Vibrio parahaemolyticus (Vp) from salmon consumed raw, the isolated strain VBNC-VpRS1 and the virulent strain Vp17802 were separately orally administered to C57BL/6J mice. The behavior of the mice was observed for the following 72 h, and the disease activity index (DAI) score, Vp load, intestinal damage, tight junction (TJ) protein expression and cytokine levels were measured. It was found that symptoms of infection with VBNC-VpRS1 appeared six hours later than those of infection with Vp17802. Compared with the control group, infection with VBNC-VpRS1 and Vp17802 significantly increased the DAI score, colonic Vp load and the levels of proinflammatory cytokines in mice (P < 0.01 and P < 0.001), and significantly decreased the colon length, anti-inflammatory factor levels and TJ protein expression (P < 0.01, P < 0.001 and P < 0.05). The infected mice showed severe intestinal mucosal tissue defects with hemorrhagic effusion and neutrophil infiltration. Moreover, the colonic Vp load and the degree of pathologic damage in the mice infected with VBNC-VpRS1 were higher than (P < 0.05) those in the mice infected with Vp17802, whereas VBNC-VpRS1 was less effective than Vp17802 in inhibiting the intestinal barrier function and promoting inflammatory responses (P < 0.05). VBNC-VpRS1 can be resuscitated in vivo and has strong colonic adhesion and invasion abilities. As VBNC Vp seriously threatens human health, seafood products consumed raw should be included in the monitoring of Vp.

Objective: To compare the effects of four lipid components (oil fractions 1, 2 and 3, and phospholipids) extracted from egg yolk oil on promoting peptic gastric ulcer healing in mice. Methods: The lipid components at 0.3 g/d for the oil fractions and 0.1 g/d for phospholipids were separately given to six-week-old mice with gastric ulcer by gavage for five days. Afterwards, the extent of gastric antrum ulcer and histopathological alterations were analyzed, superoxide dismutase (SOD) activity, glutathione peroxidase (GSH-Px), malondialdehyde (MDA), endothelin-1 (ET-1) and nitric oxide (NO) levels in gastric tissue were measured to evaluate the promoting-healing effect of the lipid components on peptic gastric ulcer. Furthermore, verification experiments were carried out by gavaging the mice with gastric ulcer with oil fraction 1 at doses of 0.3 and 0.15 g/d or phospholipids at doses of 0.1 and 0.05 g/d. Results: Yolk oil 1 and phospholipids significantly promoted the healing of gastric antrum ulcer. Histopathological analysis showed the four lipid components maintained cell integrity and inhibited inflammatory cell infiltration. Compared with the model group, SOD activity and GSH-Px and NO levels were significantly increased (P < 0.05 and P < 0.01), and MDA and ET-1 levels were significantly decreased after intervention with oil fraction 1 (P < 0.01 and P < 0.05). Similarly, after phospholipid treatment, SOD activity and GSH-Px levels were significantly increased (P < 0.01), and MDA and ET-1 levels were significantly decreased (P < 0.01 and P < 0.05). In the validation experiments, the low dose of oil fraction 1 could still significantly promote ulcer healing, while the dose of phospholipids could not. Conclusion: Liquid lipids (yolk oil 1) rich in n-3 polyunsaturated fatty acids (PUFAs) and arachidonic acid as well as phospholipids in egg yolk are effective in promoting the healing of peptic gastric ulcer in mice, and oral administration of 0.15 g/d of yolk oil 1 or 0.1 g/d of phospholipids can promote the healing of peptic gastric ulcer in mice.

Hyperuricemia is a risk factor for many diseases, and in turn is caused by purine metabolism disorder and the decrease of uric acid (UA) excretion. Therefore, reducing the production of UA and promoting the excretion of UA are significant ways to alleviate hyperuricemia. Although Poria cocos is an important fungus that can be used for both food and medicinal purpose, at present, there are few studies on the anti-hyperuricemic activity of P. cocos. In this context, the current study aimed to evaluate the anti-hyperuricemic effect of P. cocos powder in mice, and elucidate the underlying mechanism from the perspectives of the production and excretion of UA. The results showed that P. cocos powder significantly reduced the serum level of UA (P < 0.001) and inhibited the activity of xanthine oxidase (XOD) in the serum and liver of hyperuricemic rats. In addition, P. cocos powder remarkably improved renal function, glomerular atrophy, and renal tubule dilatation in hyperuricemic rats. Meanwhile, P. cocos powder significantly increased the relative abundance of Bacteroidetes, Alistipes and Parabacteroides, and significantly reduce the relative abundance of Firmicutes in the intestinal tract. These results speculated that P. cocos powder could promote the excretion of UA to reduce serum UA concentration by alleviating kidney damage and regulating the intestinal flora. These findings are conducive to the discovery of local specialties, and also provide some theoretical reference for the development of P. cocos related products.

Objective: To investigate the neuroprotective effect of resveratrol (Res) on tunicamycin (TM)-induced endoplasmic reticulum stress (ERS) and its mechanism. Methods: Fetal hippocampal neurons from female mice at 18 days of pregnancy were used for primary culture. The experiment was divided into a control group (without drug treatment), a TM group (2.5 μg/mL), a Res group (5 μmol/L) and a Res + TM group (5 μmol/L Res + 2.5 μg/mL TM). Cell Counting Kit-8 (CCK8) was used to detect the survival rate of hippocampal neurons and the optimal concentration and action time of TM and Res were determined. Flow cytometry was used to detect the cell apoptosis and cycle of primary neurons, and Western blot was used to analyze the expression of proteins related to endoplasmic reticulum stress, autophagy, apoptosis and cell cycle. Results: Preconditioning with Res (5 μmol/L) for 10 h could reduce the inhibitory effect of TM on the survival rate of primary neurons and reactivate the cell cycle of neurons, promoting its transition from G1/G0 to S phase. Compared with the TM group, preconditioning with Res for 10 h significantly decreased the relative expression levels of glucose-regulated protein 78 (GRP78) (P < 0.01), caspase 3 (P < 0.05), but significantly increased the protein expression levels of autophagy-related protein Beclin-1 (P < 0.05) , microtubule-associated protein 1 light chain 3B (LC3B) (P < 0.05), phosphorylated glycogen synthase kinase 3β (p-GSK3β) (P < 0.001) and apoptosis-related protein B-cell lymphoma 2 (Bcl2) (P < 0.01), as well as inhibited cell apoptosis induced by TM. Conclusion: Res can attenuate TM-induced ERS in primary neurons and protect primary neurons. The mechanism is related to the regulation of Res on cell survival rate, cell cycle distribution and the expression of autophagy- and apoptosis-related proteins.

Sea cucumber is a traditional Chinese tonic with various bioactivities. This study systematically investigated the immunomodulatory effect of saponins extracted from sea cucumber residues (SCRSS) at doses of 2.5, 5.0 and 10.0 mg/(kg mb·d) on immunosuppressive mice. The results showed that SCRSS at a dose of 5.0 mg/(kg mb·d) increased the body mass, spleen index, and thymus index by 15.3%, 23.8%, and 39.8%, respectively, compared to the model control group, and it also significantly increased the phagocytic index in immunosuppressive mice (P < 0.01). Moreover, All the doses of SCRSS remarkably increased serum cytokine levels, promoted the proliferation activity of splenic lymphocytes and peritoneal macrophages. Importantly, the middle dose (5.0 mg/(kg mb·d)) of SCRSS was more effective to upregulate the expression of nucleotide binding and oligomerization domain (NOD)1, NOD2, receptor interacting protein 2 (RIP2) and nuclear factor (NF)-κB in immunosuppressive mice. Thus, SCRSS may be used as a functional food supplement to improve immunity.

Objective: To investigate the anti-aging activity of polysaccharide from Dendrobium officinale leaves in Caenorhabditis elegans. Methods: The suspension of Escherichia coli OP50 containing polysaccharide at different concentrations (0.5, 1.0 and 2.0 mg/mL) was given to the nematode on a daily basis. A suspension of Escherichia coli OP50 was used as a control to evaluate the effects of the polysaccharide on the lifespan, reproductive capacity, locomotion behavior, and stress resistance of?C.?elegans.?Meanwhile, the effects of the polysaccharide on antioxidant function in C.?elegans were investigated by measuring the accumulation level of reactive oxygen species (ROS) and antioxidant enzyme activities. Results: Within the tested concentration range, the polysaccharide prolonged the lifespan, increased locomotion capacity and stress resistance of C. elegans without damaging its reproductive capacity, increased the activity of catalase, superoxide dismutase and significantly reduced the content of malondialdehyde (MDA) (P < 0.05). The results showed that the polysaccharide from D. officinale leaves improves the activity of antioxidant enzymes and stress resistance, reduces ROS levels and alleviates cell oxidative damage, thereby prolonging the lifespan of C.?elegans.

Objective: To investigate the ameliorative effect and underlying mechanism of human-origin Lactobacillus combined with inulin in type 2 diabetic mice (T2DM). Methods: Obese/diabetic?(db/db)?mice?were consecutively administrated with a cocktail of four strains (each with a viable count of 1.0×109 CFU/mL) of human-origin Lactobacillus at a dose of 10 mL/(kg mb·d), and fed a basal incorporated with 5% inulin for dietary intervention on mice. Body?mass,?feed intake and fasting blood glucose levels were?measured?once?a?week. At the late stage of intervention, oral glucose tolerance and insulin resistance tests were performed. After completion of the experiment, fasting blood glucose, blood lipids, glycated serum protein (GSP), the mRNA expression of inflammatory factors, and phosphatidylinositol-3-kinase (PI3K) and serine/threonine kinase (AKT) protein expression were measured. Liver, kidney and pancreas tissues were collected and stained with hematoxylin-eosin (HE) to observe histomorphology. Results: Human-origin Lactobacillus coordinated with inulin effectively regulated blood glucose and lipid levels, reduced the expression of GSP and improved insulin resistance. The mRNA expression of pro-inflammatory factors interleukin (IL)-6 and IL-1β were significantly inhibited and the mRNA expression of anti-inflammatory factor IL-10 was promoted. Furthermore, the expression of PI3K and AKT proteins were increased significantly, and pathological damage was significantly improved in liver, kidney and pancrea tissues. Conclusion: Human-origin Lactobacillus coordinated with inulin can alleviate type 2 diabetic symptoms in mice by reducing insulin resistance and inflammatory response, and activating the PI3K/AKT signaling pathway.

Objective: To explore the effect and molecular mechanism of high F-value corn peptide on improving exercise capacity, so as to provide theoretical support for its development as a sports nutritional supplement. Methods: Eighty SD rats were randomly divided into four groups: a control group and high F-value corn peptide with low-dose, medium-dose and high-dose groups. Each morning, the rats in low-dose, medium-dose and high-dose groups were orally administered with 0.1, 0.2 and 0.4 g/kg mb of high F-value corn peptide respectively, and the rats in the control group were administered with the same volume of normal saline. All rats received one-hour swimming training without weight loading every day over a period of 8 weeks and also performed exercise in the first five days every week with two-day intervals. After the last treatment, weight-bearing exercise was carried out and the time to exhaustion was recorded. Blood lactate levels were determined as well. After being at rest for three days, the rats were sacrificed to harvest peripheral blood and skeletal muscle tissue. Subsequently, commercial test kits were used to measure malondialdehyde (MDA) concentration, and the activities of superoxide dismutase (SOD) activity and adenosine triphosphate (ATP) synthase and hydrolase in muscle. Meanwhile, the expression of the antioxidative stress regulator nuclear factor erythroid-2 related factor 2 (Nrf2), Kelch-like?ECH-associated protein?1 (Keap1), the mitochondrial fusion protein mitofusin 2 (Mfn2) and the mitochondrial fission protein dynamin-related protein 1 (Drp1) were detected by Western blot analysis. Results: Compared with the control group, high F-value corn peptide significantly prolonged the exhaustive exercise time of mice (P < 0.05) in a dose-dependent manner, and dramatically reduced the level of blood lactic acid at 5 and 15 min after exhaustive exercise (P < 0.05). The level of blood lactic acid in the high-dose group was significantly lower than that in the low-dose group (P < 0.05). In addition, high F-value corn peptide dose-dependently significantly elevated the activities of ATP synthase and hydrolase in skeletal muscle of rats compared to the control group (P < 0.05). We also found that oral administration of high F-value corn peptide could increase SOD activity and reduce MDA production in skeletal muscle of experimental rats, increase the expression of Nrf2 in the nucleus and of Keap1 protein in the cytoplasm, significantly increase the expression of Mfn2, and significantly reduce the expression of Drp1. Conclusion: High F-value corn peptide improves exercise capacity in experimental rats by improving the mitochondrial function of skeletal muscle.

Objective: To compare the alleviative effects of native and fermented white ginseng, red ginseng, black ginseng and ginseng berry on exercise-induced fatigue and oxidative damage in mice. Methods: Male Institute of Cancer Research (ICR) mice were assigned to 10 groups of 12 animals each: blank control, positive control (powder in rhodiola capsule), and native and fermented white ginseng, red ginseng, black ginseng and ginseng berry (0.5 g/(kg mb·d)). The animals in the experimental groups were administered for 30 straight days. Body mass and food intake were recorded. Serum urea nitrogen and serum and muscle lactic acid levels were measured, and the changes in blood glucose levels, the levels of glycogen in muscle and liver and the expression levels of glutathione peroxidase (GSH-Px), total superoxide dismutase and malondialdehyde (MDA) in liver were analyzed. The correlation between anti-fatigue and antioxidant indexes was analyzed. Results: Body mass increased with administration time for all experimental groups. After 30 days of administration, no significant difference in body mass gain or food intake changes was found among all groups. Compared with the blank control group, the positive control group had a strong protective effect on oxidative damage induced by fatigue stress. Comparison with the positive group, intervention with fermented black ginseng significantly prolonged the exhaustive swimming time of mice (P < 0.01), reduced the levels of blood lactic acid, serum urea nitrogen and muscle lactic acid (P < 0.01), increased the levels of blood glucose, liver glycogen and muscle glycogen (P < 0.05) and the activity of GSH-Px (P < 0.01), and decreased the content of MDA in the liver (P < 0.01). Conclusion: Fermented black ginseng reduces or eliminates oxidative damage induced by fatigue stress and protects against oxidative stress and exercise fatigue, and its anti-fatigue and antioxidant effects are more pronounced than those of the other ginseng products and powder in rhodiola capsule at the same dose.

The protective effect of oligomolymeric procyanidins (LPOPC) and six monomeric procyanidins from litchi pericarp on ultraviolet B (UVB, 280–320 nm)-induced oxidative damage in HaCaT cells was evaluated in this study. UVB-damaged HaCaT cells were treated with para-aminobenzoic acid (PABA) as a positive control, LPOPC and the monomeric procyanidins, separately. Native and irradiated cells without drug treatment were used as a control group and a model group, respectively. Cell viability was detected by the CCK-8 method. The activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were detected using commercial kits, and the levels of reactive oxygen species (ROS), glutathione (GSH) and malondialdehyde (MDA) were also measured. These results showed that LPOPC and the six monomeric compounds significantly increased the viability of HaCaT cells damaged by UVB, reduced the generation of intracellular ROS and MDA, increased the activities of SOD, CAT and GSH-Px and GSH levels. The protective effect of procyandin A2 against oxidative stress in HaCaT cells was the most significant among the six monomeric compounds, which was equivalent to that of PABA. Therefore, LPOPC and the monomeric compounds have a good protective effect on UVB-induced oxidative damage in HaCaT cells by enhancing intracellular antioxidant capacity and inhibiting lipid peroxidation. It is suggested that procyanidin A2 from litchi pericarp is an active component with the strongest protective effect.

We aimed to investigate the efficacy of carboxymethyl cellulose (CMC) in inducing C. laurentii to antagonize postharvest penicillium (Penicillium expansum) and green mold (Penicillium digitatum) in ‘Shatangju’ mandarin. In this study, the culture time of C. laurentii induced by 0.5% CMC (mass fraction) was optimized for improved antagonistic effect against blue and green mold in commercially available ‘Shatangju’ mandarin. Using sterile water as a control, the effect of C. laurentii cultures induced and not induced by 0.5% CMC on the resistance to blue and green mold, the induction of disease defense system formation and the storage quality of ‘Shatangju’ mandarin was explored. The results showed that the optimal induction time for C. laurentii against both molds was 72 h. The biocontrol of C. laurentii against the two molds was significantly better at 72 h than at other induction times (P < 0.05). C. laurentii induced by 0.5% CMC for 72 h significantly inhibited the incidence and lesion diameter of blue and green mold (P < 0.05). In addition, it increased the activities of β-1,3-glucanase, chitinase, phenylalamine ammonia lyase and polyphenoloxidase and the contents of total phenols and flavonoids in citrus fruit on the eighth day of storage compared to the control group, thereby maintaining the nutritional quality of ‘Shatangju’ mandarin during storage. Accordingly, it was concluded that the addition of 0.5% CMC to the culture medium can improve the biocontrol efficacy of C. laurentii. The CMC-induced culture of C. laurentii can increase disease defense-related enzyme activities, promote the synthesis and accumulation of antioxidant substances in ‘Shatangju’ mandarin, inhibit the occurrence of postharvest blue and green mold, and consequently maintain the storage quality of the fruit.

Fresh-cut cauliflower is prone to oxidative browning and quality deterioration during storage and sales. Thus, there is an urgent need to develop effective methods for maintaining the quality of fresh-cut cauliflower. In this experiment, ‘ummer flower’ cauliflower was used as the experimental material and soaked in limonene, and the preservation effect of limonene treatment on fresh-cut cauliflower was explored by measuring physiological metabolism, taste and flavor indexes. The results showed that limonene treatment of fresh-cut cauliflower could effectively inhibit the increase of browning index (BI), mass loss rate and respiratory intensity, and slow down the decrease of L* value and total solid solids (TSS) content. Moreover, limonene treatment could increase the activity of antioxidant-related enzymes, maintain the contents of antioxidants (ascorbic acid (AsA) and glutataione (GSH)), increase 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity and total antioxidant capacity (TAC), reduce the accumulation of MDA, superoxide anion radical and hydrogen peroxide, reduce lipoxygenase (LOX) activity, delay membrane lipid peroxidation, and maintain the quality of fresh-cut cauliflower during storage. Further results showed that limonene treatment could effectively maintain the levels of alkanes, aromatic components and other volatile substances in fresh-cut cauliflower and, consequently, the odor characteristics during storage without having any adverse effect on the taste of fresh-cut cauliflower. In summary, limonene treatment can effectively inhibit the quality deterioration and extend the shelf life of fresh-cut cauliflower. This study can provide a theoretical basis for the development of preservation technologies for fresh-cut cauliflower.

In order to explore the survival and underlying mechanism of hybrid grouper under pure oxygen and controlled atmosphere during waterless live transportation, this study investigated the changes in stress levels, serum biochemical indices, metabolites and antioxidant system in hybrid grouper in an environment simulating waterless live transportation, and it also evaluated the survival of the fish. The results showed that the survival time of grouper was (13.88 ± 1.00) h in modified atmosphere without water, which was significantly longer than that in pure oxygen environment ((10.90 ± 0.66) h) (P < 0.05). The levels of blood urea nitrogen (BUN), uric acid (UA) and creatinine (CREA), and the activity of acid phosphatase (ACP) showed an increasing trend with waterless survival time. The activities of aspartate aminotransferase activity (AST) and alanine aminotransferase activity (ALT) also increased steadily and reached the peak level at 10 h in pure oxygen atmosphere, which were (262.22 ± 1.54) and (232.05 ± 1.87) U/L, respectively, and significantly higher than those in modified atmosphere (P < 0.05); however, the activities of alkaline phosphatase (ALP) and peroxidase (POD) decreased gradually. Glycogen levels in the muscle and liver of dormant fish under cold stress was significantly decreased by 17.65% and 27.34% compared with the normal control group (P < 0.05). Lactic acid contents in muscle and liver increased significantly and returned to the normal level after resuscitation. The lactate dehydrogenase (LDH) activity in muscle fluctuated, the LDH activity in liver increased significantly (P < 0.05), and the level of malondialdehyde (MDA) showed an upward trend during waterless stress, all of which were significantly higher than those in the normal control group (P < 0.05). The activities of catalase (CAT) and superoxide dismutase (SOD), total antioxidant capacity (T-AOC) and the level of glutathione (GSH) in muscle and liver increased gradually, and decreased after resuscitation. The changes of the related indicators in the pure oxygen group were significantly greater than those in the modified atmosphere group, indicating that the modified atmosphere environment effectively alleviates kidney and liver damage as well as oxidative stress damage in grouper, has a strong regulatory effect on the energy metabolism, antioxidant system and immune defense system of grouper, and maintains its normal physiological metabolism under low temperature and waterless stress.

To investigate effect of ultraviolet (UV) irradiation on the properties of poly (butyleneadipate-co-terephthalate) (PBAT), the properties of PBAT/nano-ZnO and PBAT/nano-TiO2 composite films subjected and not subjected to UV irradiation, and the migration of nano-components from them to 3 g/100 mL acetic acid were studied. Meanwhile, the composite films were characterized by attenuated total reflection Fourier transformed infrared (ATR-FTIR) spectroscopy, field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). The results showed that the addition of each nanoparticle had little effect on the barrier performance of the composite film without UV irradiation. With the addition of nano-ZnO, the tensile strength of the composite film decreased by 22.88%-40.99%, the elongation at break decreased to 86.07%-90.98% of that of pure PBAT films, and the maximum migration of nano-ZnO was 11.82 mg/kg. The addition of nano-TiO2 had little effect on the tensile strength, but decreased the elongation at break to 73.48%-87.18% of that of pure PBAT films, and no migration of nano-TiO2 was observed (the detection limit of the method used was 0.009 mg/kg). With an increase in UV irradiation time, the elongation at break and tensile strength of the composite films decreased gradually, but the mechanical properties of the PBAT/nano-ZnO films decreased less than those of the pure PBAT and PBAT/nano-TiO2 films at the same irradiation time. After two days of UV irradiation, the oxygen permeability coefficient of the composite films increased significantly (P < 0.05), while the moisture permeability coefficient changed little. The maximum migration of nano-ZnO was 16.66 mg/kg, whereas no migration of nano-TiO2 was detected. The ester bond of the composite films was broken, the crystallinity reduced, and the surface became rough, with holes in it. We concluded that UV irradiation destroys the structure of PBAT composite film and degrades its properties. Nano ZnO can inhibit the decline of the mechanical properties of PBAT composite film to a certain extent, but its migration increases gradually.

We aimed to study the effects of multiple sprays with amino oligosaccharide (AOS) during fruit development on wound healing in harvested muskmelons. The muskmelon plants and fruits (cv. Manao) were sprayed with AOS at 2 mL/L for four times at the four stages (young fruit stage, early stage of enlargement, late stage of enlargement and mature stage) of fruit development. The effect of AOS sprays on the mass loss and disease index of harvested fruits during wound healing was evaluated. The formation of closing layer was observed on the wounds. Related metabolic enzyme activities were determined. AOS sprays effectively reduced the mass loss and disease index of wounded fruits inoculated with Trichothecium roseum during wound healing. On day 7, the mass loss and disease index of the treated group were 28.64% and 32.00% lower than those of the control group, respectively. The sprays promoted the deposition of suberin polyphenolics and lignin at wound sites, and the cell layer of suberin polyphenolics and lignin deposited was 22.70% and 25.07% thicker than those in the control group on the 5th day of healing. The sprays also increased phenylalanine ammonia lyase activity, and enhanced the contents of total phenols, flavonoids and lignin. In addition, the sprays significantly raised H2O2 content and peroxidase activity at wound sites. Taken together, preharvest multiple sprays with AOS could promote wound healing in harvested muskmelons by activating phenylpropane metabolism, and increasing H2O2 content and peroxidase activity.

The spoilage and quality deterioration of packaged low-salt paocai products caused by microorganisms has become a technical bottleneck restricting the development of the paocai industry. In order to overcome this problem, this experiment explore the effect of dielectric barrier discharge (DBD) cold plasma treatment on the inhibition of pellicle spoilage and the storage quality of instant low-salt paocai. With this in mind, the microbial population, physicochemical properties, color difference, texture and volatile compounds of paocai samples were investigated. Results showed that DBD cold plasma treatment reduced the total viable count and yeast count by 1.54–3.55 and 2.12–4.21 (lg(CFU/g)), respectively, and completely killed coliform bacteria while allowing the retention of lactic acid bacteria. Moreover, it inhibited the growth of pellicle-forming yeast obviously, thereby effectively controlling the pellicle spoilage of paocai during storage. In terms of physical and chemical properties, DBD cold plasma could inhibit the increase of pH and increase significantly the brittleness, brightness, yellowness and total acid content compared with pasteurized paocai (P < 0.05). Although higher than that in pasteurized paocai, the nitrite content in DBD cold plasma treated paocai was still far lower than the national standard limit, and gradually decreased to 3.13?mg/L as fermentation proceeded. Additionally, the major volatile compounds of paocai changed little within a short time after DBD cold plasma treatment, and DBD cold plasma treatment could inhibit the odor caused by the increase in the content of dimethyl sulfides during storage. Therefore, DBD treatment could effectively control the pellicle spoilage of low-salt paocai during storage while ensuring its quality characteristics.

This study aimed to explore the effects of re-oxygenation environments with different O2 levels after anaerobic treatment on the postharvest quality of Agaricus bisporus in order to provide a theoretical basis for the application of anaerobic treatment technology for the storage and preservation of Agaricus bisporus. Mushrooms were treated with pure N2 for six hours, and then re-oxygenation environments with different O2 levels were established through microporus modified atmosphere packaging (MAP). The respiration rate, ethylene production, anaerobic metabolite contents, mass loss percentage, appearance, texture and sensory characteristics of the mushroom samples were analyzed during storage. Ultra-low O2 environments (1%–2%) significantly inhibited the production of ethylene during storage. On the 15th day of storage, the mass loss percentage was only 1.38%, and the firmness and springiness were higher than those of the initial values by 36.38% and 5.02%, respectively. Furthermore, the mushrooms did not show obvious browning and maintained the highest sensory score during the entire storage period. However, high O2 environments (19%–20%) accelerated the deterioration of mushroom quality. Brown spots and decay were observed on the surface of mushrooms on the 9th day. The sensory scores for color, stickiness, flavor, texture, and decay were the lowest on the 15th day. Therefore, ultra-low O2 re-oxygenation environments can better maintain the quality of Agaricus bisporus by inhibiting the biosynthesis of ethylene.

The effect of postharvest pre-storage temperature on the wound healing of potato minitubers grown in an aeroponic system was evaluated, and its possible mechanisms were also explored. Potato mini-tubers (cv. Tongshu 1’) free from artificial damage were pre-stored at 4, 15 or 25 ℃ (86%–88% relative humidity) in a dark environment for 20 days. Mass loss rate was measured during pre-storage, the accumulation of suberin and cork in periderm cells was observed, the degree of suberization was examined, and the changes in phenylpropane and reactive oxygen species metabolism in potato tuber periderm were also analyzed. Results showed that pre-storage at 15 ℃ significantly promoted the accumulation of suberin polyphenolics (SPP) and suberin polyaliphatics (SPA) and the degree of suberization in periderm tissue. On the fifth day of pre-storage, the accumulation of SPP and SPA and the degree of suberization in potato tubers prestored at 15 ℃ were higher than those at 4 and 25 ℃ by 50.90% and 26.94% (P < 0.05); 44.89% and 30.23% (P < 0.05); and 27.66% and 8.18% (P < 0.05), respectively. Pre-storage at 15 ℃ also significantly increased phenylalanine ammonia lyase (PAL) activity (P < 0.05), and augmented the contents of total phenols, flavonoids and lignin. On day 5, PAL activity in potato tubers pre-stored at 15 ℃ was 34.46% and 12.64% higher than that at 4 and 25 ℃, respectively (P < 0.05). The contents of total phenols and flavonoids were 11.93% and 40.05% higher than those at 4 ℃, and 2.72% and 15.50% higher than those at 25 ℃, respectively. On the 20th day, the content of lignin in potato tubers prestored at 15 ℃ was 24.50% and 8.24% higher than that at 4 and 25 ℃, respectively (P < 0.05). In addition, pre-storage at 15 ℃ significantly increased the contents of H2O2 and superoxide anion and peroxidase (POD) activity in periderm tissue. The findings suggested that postharvest pre-storage at 15 ℃ can accelerate the wound healing of potato minitubers grown in an aeroponic system through activating phenylpropane and reactive oxygen species metabolism in periderm tissue, and increasing the accumulation of SPP and SPA and the degree of suberization.

To investigate the effects of packaging method and storage temperature on the bacterial load, diversity and metabolic pathways in mutton, postportem mutton was stored in air packaging (AP), vacuum packaging (VP) or skin packaging (SP) for 30 days at chilled ((4 ± 1) ℃) or superchilled temperature ((?1.7 ± 0.2) ℃). The bacterial community composition during the storage period was analyzed by a combination of plate counting and high-throughput sequencing. The results showed that total viable count (TVC), Lactobacillus count, Pseudomonas count, Staphylococcus/Micrococcus count, mold and yeast count, and psychrophilic bacterial count were all lower in the SP group than in the AP and VP groups, and all the bacterial counts were significantly lower in the superchilled storage group than in the chilled storage group. The bacterial diversity showed a decreasing trend with storage time, and it was more complex in the chilled storage group than in the superchilled storage group. A total of 30 bacterial genera belonging to 10 bacterial phyla were obtained by high-throughput sequencing of the V3–V4 region of the 16S rDNA gene. For all samples, the most abundant phyla were Proteobacteria and Firmicutes. Pseudomonas was the dominant genus in the AP group but less abundant in the SP and VP groups. Carnobacterium, Brochothrix and Lactobacillus were the dominant genera at the end of storage for all three groups. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that carbohydrate, amino acid and nucleotide metabolism were the major metabolic pathways during the storage of mutton. Amino acid metabolism was dominant during the early storage period, while carbohydrate and nucleotide metabolism were dominant during the late storage period. The difference in metabolic abundance was mainly attributed to the difference in microflora structure caused by packaging methods and storage temperatures. In conclusion, SP combined with superchilled temperature can reduce the microbial load and community diversity in mutton during storage, helping to maintain the quality of mutton.

Objective: To investigate the effect of 60Co-γ irradiation on the quality of harvested Morchella angusticeps during cool storage. Methods: M. angusticeps was irradiated with different absorbed doses of 60Co-γ (1.64, 2.18, 2.43 and 2.93 kGy), and the sensory quality and physiological and biochemical indexes of the control and irradiated samples during cold storage were evaluated. Orthogonal partial least square discriminant analysis (OPLS-DA) was used to establish a discriminant model for irradiation treatment based on the physiological and biochemical indexes of M. angusticeps, and the significantly differential indexes between the control and irradiation groups were identified using variable importance in the projection (VIP). Results: The patterns of changes in the sensory quality and physiological and biochemical characteristics of M. angusticeps irradiated with different doses of 60Co-γ were different during storage at 4 ℃. After five days of storage, the activity of catalase and the contents of total phenols and flavonoids in the 1.64 and 2.18 kGy irradiation groups were increased, malondialdehyde content and the activities of polyphenol oxidase and peroxidase were reduced, and browning and softening were retarded as compared to the control group. The dose of 1.64 kGy provided better preservation of the quality of M. angusticeps (P < 0.05). On the contrary, the doses of 2.43 and 2.93 kGy increased the quality deterioration of M. angusticeps at the end of storage. The developed discriminant model could distinguish the differences between the control and irradiation treatments effectively. The activities of catalase and peroxidase were identified as significantly differential indexes. Conclusion: 60Co-γ irradiation at doses of 1.64 and 2.18 kGy can delay the quality deterioration significantly and prolong the shelf life of M. angusticeps, the dose of 1.64 kGy being more effective. The OPLS-DA model could effectively distinguish between the different treated sample groups.

In this study the antibacterial effect of oxidized starch (OST) was analyzed by the inhibition zone method and the effect of OST on preserving the quality of strawberries was investigated by measuring mass loss percentage, decay incidence and total viable count. The results indicated that OST exhibited potent antimicrobial effects against common pathogenic bacteria such as Staphylococcus aureus and Escherichia coli, as well as penicillium, a common spoilage organism of strawberries. The higher the proportion of carboxyl groups in OST, the stronger the antimicrobial effect. Specifically, the diameters of the zones of inhibition of OST containing 57% carboxyl (OST-57) against Staphylococcus aureus, Escherichia coli, and penicillium were (29.00 ± 0.87), (28.00 ± 1.73) and (15.75 ± 0.65) mm, respectively. OST-57 coating effectively inhibited the growth of total viable count, significantly reduced the mass loss percentage and decay incidence of strawberries (P < 0.05), delayed the change of hardness and chewiness during the ripening process of strawberries, and preserved the contents of soluble solids, anthocyanins, and other nutrients (P < 0.05). To sum up, OST-57 can effectively delay the ripening and senescence of strawberries, and thus has application value for the post-harvest preservation of vegetables and fruits as a new coating material.

Acrylamide is a ubiquitous toxicant in various heat-processed foods. Coffee is one of the most important dietary sources of acrylamide. This paper explains the liver toxicity, neurotoxicity and reproductive toxicity of acrylamide in animals and cells, and it analyzes the major pathway for acrylamide formation during coffee roasting. During the selection and roasting of raw coffee beans and coffee extraction and brewing, the factors influencing acrylamide formation include the types of coffee beans, roasting temperature, roasting time and storage conditions. Different coffee processing methods can also cause differences in acrylamide content. Furthermore, this review summarizes the efficient measures to prevent the formation of acrylamide during coffee roasting, with the aim of providing a theoretical reference for the control of acrylamide formation in the food industry.

With the implementation of the Outline of “Healthy China 2030” Plan and the continuous enhancement of consumers’ concept of healthy diet, “low salt and phosphorus free” healthy meat products have gradually become a trend of development in the meat products industry. However, simply reducing the addition of NaCl and polyphosphates will seriously affect the cooking yield and quality of the final products. Therefore, it is of great significance to seek green and healthy alternatives to NaCl and polyphosphates. In recent years, the basic amino acids arginine, lysine and histidine have attracted extensive research attention for their application as substitutes for NaCl and polyphosphates in the meat products industry. This paper reviews the latest progress in the study on the regulatory effects of basic amino acids on the structure, solubility, and emulsification and gelation properties of myofibrillar proteins, as well as the underlying mechanisms. Meanwhile, the effects of basic amino acids on meat quality (color, water retention, texture characteristics, and oxidation stability) are also summarized. Hopefully, this review will provide a theoretical basis for the follow-up research and practical application of basic amino acids in the meat industry.

Meat is rich in protein and contains the essential amino acids required for the human body. The ratio among amino acids in meat is close to that needed for the growth and maintenance of human tissues. The nutritional value of meat is mainly evaluated by its protein content and essential amino acid pattern, but the digestibility of meat protein has received little research attention. The digestibility of protein can be affected by various factors such as protein source, muscle fiber type, protein oxidation degree, and processing technology. Improving the digestibility of meat protein is essential for human growth and maintenance, and it can also prevent some diseases. This article systematically summarizes and categorizes the external and internal factors affecting meat protein digestibility, and discusses the current status of research on those factors, hoping to guide and help the processing and utilization of meat protein.

Anthocyanins and vitamin C (VC) are important functional substances in fruit and vegetable beverages. However, anthocyanins and VC degrade each other in fruit and vegetable beverages, causing significant losses of their color, flavor and nutritional value. Considering that their interaction mechanism is unclear yet, the oxidation and condensation hypotheses of the anthocyanins-VC interaction are reviewed in detail, starting with the degradation routes of anthocyanins and VC. The effects of anthocyanin structure, vitamin C concentration, temperature, the presence of oxygen, polyphenols and biomacromolecules on the anthocyanins-VC interaction are elucidated. The applications of colorimeter, UV-visible absorption spectroscopy, high performance liquid chromatography, electron spin resonance spectroscopy and nuclear magnetic resonance spectroscopy in studies on the anthocyanins-VC interaction are summarized. This review provides a theoretical basis to understand the interaction mechanism between anthocyanins and VC, and inspire future research to inhibit the interaction between anthocyanins and VC.

Oleogelation is one of the most potential technologies to prepare plastic fats with zero trans-fatty acid and low saturated-fatty acid content. This process fabricates oleogels with thermo-reversibility and solid-like behaviors under different processing conditions (e.g., heating and stirring, or templated dehydration) after addition of an oleogelator to vegetable oils. Natural waxes have been demonstrated to be the most efficient crystalline oleogelators by virtue of their low price, easy accessibility and use at low concentrations for the preparation of oleogels with good texture. Herein, the fabrication technologies for oleogels based on natural waxes of different composition are systematically reviewed, with a focus on the factors affecting the crystallinity of wax-based oleogels, and the advantages and applications of wax-based oleogels are briefly described. Furthermore, the challenges and future trends in the development of natural wax-based oleogels in the industrial production of special oils and fats for foods are discussed.

Foam is a disperse system in which a gas is dispersed in a liquid or semi-solid medium. It plays an important role in shaping the taste, texture and appearance of interface-dominated foods such as cream, ice cream, and beer. Researchers usually expect to clarify the formation and stabilization mechanism of foam in the food system when they explore an innovative combination of foaming technology and various interface-dominated foods. However, foam, a highly thermodynamically unstable system, is prone to drainage, polymerization, and disproportionation. There are various factors to consider when acquiring the best foam stability in a complicated food system. Therefore, this paper starts with a discussion of the mechanisms for foam instability, followed by a systematical review of the foaming characteristics of different substances and the mechanisms for the stability of foam in different foods. This paper focuses on explaining the effect of surfactants or processing aids, solid particles, and processing conditions or technologies on foam stability from the perspective of the gas-liquid interface, aiming to provide a theoretical guidance for the development and stabilization of foam in interface-dominated foods.