Family cohesion and intuitive eating in Chinese college students: A serial mediation model.

Improving intuitive eating can effectively prevent emotional eating, restrained eating, and overeating, and help improve people's physical and mental health. Based on the acceptance model of intuitive eating, ecological systems theory, family stress model, and transactional model of stress and coping, the present study aimed to explore the relationship between family cohesion and intuitive eating and its underlying mechanisms through a cross-sectional study design. A random sample of 702 college students from 29 provinces in China, aged from 18 to 26 years (54.56% male, M age = 21.12 years), voluntarily participated in the survey. Demographic variables, family cohesion, intuitive eating, perceived stress, and coping style were measured. The results indicated that family cohesion was significantly positively correlated with intuitive eating and the direct effect between them was significant. Meanwhile, there was a significant indirect effect of family cohesion on intuitive eating through perceived stress and positive coping styles. Moreover, perceived stress and positive coping styles, rather than negative coping styles, acted as serial mediators in the association between family cohesion and intuitive eating. The findings shed light on the prevention and intervention for disordered eating and obesity and provided a new theoretical perspective for the mental health education of college students. In addition, implications and directions for future research were also discussed.

Phthalates in Chinese vehicular environments: Source emissions, concentrations, and human exposure.

Phthalates are typical air pollutants in vehicular environment since numerous synthetic materials that might contain phthalates are widely used to fabricate vehicle interiors (e.g., seat cushions, floor mats and dashboards). Hitherto, the importance of phthalate pollution in vehicular environment is not well-recognized because people spend only a small portion (around 8%) of their time in vehicles. In this study, the mass fractions of six phthalates in nine materials commonly used in Chinese vehicles (floor mats and seat cushions) were measured. Two phthalates, di-n-butyl phthalate (DnBP) and di-2-ethylhexyl phthalate (DEHP), were identified in most materials (the other phthalates were not detected). The emission characteristics of DnBP and DEHP from these materials were further investigated. The measured emission parameters were used as input for a mass-transfer model to estimate DnBP and DEHP concentrations in cabin air. Finally, the ratios between human exposures (via inhalation and dermal absorption from the gas phase) in vehicular environment and the total exposures in typical indoor environments (e.g., residences and offices) were estimated to be up to 110% and 20% for DnBP and DEHP, respectively. Based on these results, the vehicular environment might be a considerable site for human exposure to airborne phthalates.

Effects of brown seaweed polyphenols, α-tocopherol, and ascorbic acid on protein oxidation and textural properties of fish mince (Pagrosomus major) during frozen storage.

BACKGROUND: Frozen storage of minced fish is currently one of the most important techniques to maintain its functional properties. However, some deterioration does occur during frozen storage and cause quality loss. The effects of brown seaweed polyphenols, α-tocopherol, and ascorbic acid on lipid and protein oxidation and textural properties of red sea bream (Pagrosomus major) during 90 days of frozen storage at -18 °C were investigated. RESULTS: All added antioxidants at 1 g kg-1 resulted in significantly lower thiobarbituric acid-reactive substances (TBARS) compared to the control during the 45 days of frozen storage. The antioxidants were also effective in retarding protein oxidation concerning to total sulfhydryl content and protein carbonyl content. Brown seaweed polyphenols and α-tocopherol significantly retarded the inactivation of Ca2+ -ATPase activity during the first 45 days, whereas ascorbic acid had no such effect. The antioxidant activity showed either an invariable or decrease trend after 45 days storage. Adding antioxidants had a significant effect on the breaking force of the gels during the frozen storage period. CONCLUSION: These results indicate that brown seaweed polyphenols and α-tocopherol can be used to prevent oxidative reactions and thus maintain the structure of the gel formed by fish mince during frozen storage. © 2016 Society of Chemical Industry.

Inhibition of advanced glycation endproducts during fish sausage preparation by transglutaminase and chitosan oligosaccharides induced enzymatic glycosylation.

Advanced glycation endproducts (AGEs) are the harmful products of non-enzymatic reactions in foods formed during the heating process. In order to reduce the content of AGEs in foods, the inhibitory effect of different proportions of transglutaminase (TGase) and chitosan oligosaccharides (COS) on the AGEs of seabream fish meat sausage was studied. The results indicated that the TGase/COS ratio of 1 : 1 could inhibit the formation of AGEs, showing especially a decreased Nε-carboxymethyl-lysine (CML) content and a twice higher inhibition rate (36.4%) than that by aminoguanidine (17.4%), a commonly effective positive inhibitor of AGEs. The data of lysine, fructosamine, and glucosamine contents, combined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses, demonstrated that cross-linking of proteins and glycosylation of glutamine induced by TGase and COS resulted in steric hindrance that inhibited glycation. These findings revealed that TGase catalyzed glycosylation with COS differently from general antioxidants had potential as an effective treatment to inhibit the formation of AGEs in fishery products.

Impacts of glycation and transglutaminase-catalyzed glycosylation with glucosamine on the conformational structure and allergenicity of bovine ß-lactoglobulin.

ß-Lactoglobulin (ß-LG) is recognized as the major milk allergen. In this study, the effects of transglutaminase (TGase) and glucosamine (GlcN)-catalyzed glycosylation and glycation on the conformational structure and allergenicity of ß-LG were investigated. The formations of cross-linked peptides were demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and GlcN-conjugated modification was identified using matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS). Structural analysis revealed that glycosylation and glycation of ß-LG induced unfolding of the primary protein structure followed by a loss of the secondary structure. As revealed by circular dichroism (CD) spectroscopy, glycosylated ß-LG exhibited the highest increase in the ß-sheets from 32.6% to 40.4% (25 °C) and 44.2% (37 °C), and the percentage of α-helices decreased from 17.7% to 14.4% (25 °C) and 12.3% (37 °C), respectively. The tertiary and quaternary structures of ß-LG also changed significantly during glycosylation and glycation, along with reduced free amino groups and variation in surface hydrophobicity. Immunoblotting and indirect enzyme-linked immuno sorbent assay (ELISA) analyses demonstrated that the lowest IgG- and IgE-binding capacities of ß-LG were obtained following glycosylation at 37 °C, which were 52.7% and 56.3% lower than that of the native protein, respectively. The reduction in the antigenicity and potential allergenicity of glycosylated ß-LG was more pronounced compared to TGase treated- and glycated ß-LG, which correlated well with the structural changes. These results suggest that TGase-catalyzed glycosylation has more potential compared to glycation for mitigating the allergenic potential of milk products.

Effect of transglutaminase-catalyzed glycosylation on the allergenicity and conformational structure of shrimp (Metapenaeus ensis) tropomyosin.

Tropomyosin (TM), a myofibrillar protein, is a major allergen in shrimp. The aim of this study was to evaluate the effect of transglutaminase (TGase)-catalyzed glycosylation on the potential allergenicity and conformational structure of TM in Metapenaeus ensis. Results showed that glycosylation of TM induced unfolding of the primary protein structure followed by loss of the secondary structure. Cleavage of certain free amino groups was observed during TGase-catalyzed glycosylation. The glycosylation rate correlated with reaction temperature. Western blotting and indirect ELISA with TM-specific polyclonal antibodies from rabbit and sera from patients allergic to shrimp demonstrated that antigenicity and potential allergenicity of TM decreased, which correlated well with the conformational changes in its structure. Considering TGase is widely utilized in the food industry, these results indicate that TGase-catalyzed glycosylation has the potential to serve as a mild method for reducing the allergenicity of shrimp products.

Effect of 4-hydroxy-2-nonenal treatment on the IgE binding capacity and structure of shrimp (Metapenaeus ensis) tropomyosin.

Lipid peroxidation can react with free amines of proteins and induce modification of structural and functional properties. This study presents the IgE binding capacity and structural changes of shrimp tropomyosin (TM) under oxidative stress with 4-hydroxy-2-nonenal (HNE). IgE binding capacity was evaluated with the dot-blot assay and inhibition enzyme-linked immunosorbent assay. A decrease in IgE binding capacity of TM was found with 0.01mM HNE treatment, which was more significant when the HNE concentration was increased to 0.5mM. The conformational changes of TM, as characterized by fluorescence spectroscopy, circular dichroism spectroscopy and ultraviolet absorption spectroscopy, correlated well with IgE binding capacity changes. Further LC-ESI-MS/MS analyses showed that the side-chain groups of alanine, leucine, lysine and histidine had been modified by HNE. These results suggested that the HNE-induced conformational changes of TM significantly influenced its allergenicity and that these changes were caused by the modification of specific amino acids residues.