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This study investigated the heat-induced interactions between wheat and buckwheat proteins by heating wheat proteins, buckwheat albumin, globulin, and mixtures of wheat flour with buckwheat albumin/globulin at 50, 65, 80, 95, and 100 °C. The results showed that the cross-linking reactions of wheat glutenin with buckwheat albumin and globulin initiated at 80 and 95 °C, respectively. Buckwheat albumin decreased the extractability of α-gliadin by 35 % at 95 °C and 5.9 % at 100 °C. The linkage of buckwheat globulin to wheat glutelin prevented part of the wheat gliadin from linking to glutelin, resulting in the extractability of α- and γ-gliadin increased by 8.6 % and 11 % at 95 °C, respectively. The chemical forces results indicated that interactions between wheat and buckwheat proteins were primarily driven by disulfide bonds and hydrophobic interactions. This study provides a theoretical basis for better regulating the wheat-buckwheat protein network to improve the quality of buckwheat-enriched products., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Antimicrobial polycationic peptide ε-poly-l-lysine (ε-PL) enhanced the freeze-thaw tolerance of industrial yeast; the enhancement mechanism of ε-PL on yeast was studied. Results showed that a ε-PL coating was observed in ε-PL-treated yeast. After 4 times of freeze-thaw, the cell viability, glycerol content, and CO 2 production of 0.6 mg/mL ε-PL-treated yeast were higher than those of untreated yeast, specifically, the cell viability of ε-PL-treated yeast was 87.6%, and that of untreated yeast was 68.5%. Metabolomic results showed that the enhancement mechanism of ε-PL on yeast was related to the promotion of cell membrane-related fatty acid synthesis pathways before freeze-thaw treatment, and the promotion of trehalose biosynthesis and glycerophospholipid metabolism pathways after freeze-thaw. Furthermore, ε-PL induced inhibition of the tricarboxylic acid cycle, resulting in a longer stationary phase at the beginning of the freeze-thaw and ultimately providing a higher level of freeze-thaw stress tolerance than untreated yeast., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The effect of egg white protein addition on the fibrous structure and protein aggregation of textured wheat gluten (TWG) extrudates was investigated. The hardness, springiness, chewiness, and degree of texturization of TWG significantly increased with the addition of egg white protein. Analysis of morphological characteristics showed a positive effect of egg white protein on the formation of the fibrous structure of TWG. The results of size-exclusion high performance liquid chromatography (SE-HPLC) indicated that the egg white protein improved the degree of wheat gluten aggregation, and the analysis of the protein intermolecular forces proved that disulfide bonds were the main contributor to the cross-linking of protein. In addition, an increase in the β-sheets also indicated an increase in protein aggregation induced by egg white protein. The addition of egg white protein promoted protein interactions and improved the fibrous structure of TWG., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

To reduce the rehydration time and improve the quality of textured wheat gluten (TWG), the effects of steam pretreatment and water temperature (45 °C, 65 °C, and 85 °C) on the rehydration of TWG were investigated. Four different models were used to describe the rehydration kinetics: Peleg, Weibull, first-order, and exponential association models, with the Weibull model found to give the best fit. High temperature induced deterioration of textural properties and oral processing behavior and increased the rehydration loss ratio, while steam pretreatment reduced these negative changes. Morphological results showed that the surface and cross-sectional structure were conducive to water diffusion with steam pretreatment. Low-field nuclear magnetic resonance and infrared thermal results indicated that steam pretreatment promoted the diffusion of water and reduced the time required to reach thermal equilibrium. This work provides a fast rehydration method for TWG to help in the future production of high-quality meat analogues., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Different methods used to process green tea powder noodles (GTPN) were compared by analyzing the quality and chemical components of the final products. Significant differences were observed in the discoloration rate, color loss, and lightness of all noodles. Polyphenol oxidase activity was effectively inhibited through the heat treatment, resulting in retardation of the GTPN discoloration rate. However, heat-exposed GTPN showed a higher surface lightness due to a greater loss of chlorophyll. The chlorophyll contents of GTPN prepared with a new method (a combination of water treatment and heat exposure) were prominently higher than those prepared by heat treatment alone, and exhibited less color loss. The heat-exposed noodles had relatively low free polyphenol contents, and their textural properties were not significantly decreased after 28 d. Therefore, combining water treatment and heat exposure in the preparation process has great potential for increasing the stability of GTPN., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

In this study, functional, rheological and physicochemical characteristics were carried out for composite gluten-free (CGF) flours, dough and biscuits, respectively fortified with fermented and unfermented Agaricus bisporus polysaccharide (FABP and UABP) flours. Addition of both FABP flour and UABP flour improved functional properties, while addition of FABP flour decreased viscosity property. Incorporation of both polysaccharide flours in CGF biscuit dough revealed a significant increase in rheological moduli (G' and G″) and a decrease in tan (δ). Supplementation of UABP flour increased thickness, whereas supplementation of FABP flour increased diameter and spread ratio. All CGF biscuit formulations exhibited lower fracture strength and hardness compared to the control. Furthermore, both UABP flour and FABP flour formulation (F 3 ) contained the highest nutrients in terms of protein, dietary fibers, amino acids and minerals among the CGF biscuit formulations. The sensory evaluation result showed that FABP flour formulation (F 1 ) and UABP flour F 1 were most acceptable., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The impact of alkali addition on the degree of gluten polymerization and textural characteristics of textured wheat protein was investigated. Results showed that the extrusion process increased the average molecular weight of gluten as evidenced by SDS-PAGE and SDS extractable protein. The addition of alkali not only promoted the degree of gluten polymerization, but also induced dehydroalanine-derived cross-linking. Alkali addition decreased the content of cystine and increased the contents of dehydroalanine and lanthionine. The obvious decrease of free SH showed that dehydroalanine-derived cross-linking was quantitatively less crucial than disulfide cross-linking. Furthermore, the protein cross-linking induced by alkali improved the texture properties of gluten extrudates. SEM analysis showed extrusion under alkaline condition conferred a more fibrous microstructure as a consequence of a compact gluten network., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The present study investigated the combined effects of aqueous ozone treatment and modified atmosphere packaging (MAP) on prolonging the shelf-life of semi-dried buckwheat noodles [SBWN; moisture content (22.5±0.5%)] at 25°C. Firstly, the different concentrations of ozonated water were used to make SBWN. Subsequently, SBWN prepared with ozonated water were packaged under six different conditions and stored for 11days. Changes in microbial, chemical-physical, textural properties and sensorial qualities of SWBN were monitored during storage. Microbiological results indicated that adopting 2.21mg/L of ozonated water resulted in a 1.8 log 10 CFU/g reduction of the initial microbial loads in SBWN. In addition, MAP suppressed the microbial growth with a concomitant reduction in the rates of acidification and quality deteriorations of SBWN. Finally, the shelf-life of sample packed under N 2 :CO 2 =30:70 was extended to 9days, meanwhile textural and sensorial characteristics were maintained during the whole storage period., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Methoxy-ρ-benzoquinone (MBQ) and 2, 6-dimethoxy-ρ-benzoquinone (DMBQ) are two potential anticancer compounds in fermented wheat germ. In present study, modeling and optimization of added macronutrients, microelements, vitamins for producing MBQ and DMBQ was investigated using artificial neural network (ANN) combined with genetic algorithm (GA). A configuration of 16-11-1 ANN model with Levenberg-Marquardt training algorithm was applied for modeling the complicated nonlinear interactions among 16 nutrients in fermentation process. Under the guidance of optimized scheme, the total contents of MBQ and DMBQ was improved by 117% compared with that in the control group. Further, by evaluating the relative importance of each nutrient in terms of the two benzoquinones' yield, macronutrients and microelements were found to have a greater influence than most of vitamins. It was also observed that a number of interactions between nutrients affected the yield of MBQ and DMBQ remarkably., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The impact of alkali addition on the dough rheological properties and quality of buckwheat noodles was investigated. Farinograph measurements showed that the addition of alkali increased the water absorption and development time of the dough. Dynamic rheological properties analysis showed that alkali addition enhanced G' and G″ of dough. In addition, the texture properties of buckwheat noodles improved by the increase of the hardness and tensile force. Furthermore, an obvious decrease in the intensity of the protein bands with lower molecular weights was observed in SDS-PAGE patterns and the extractability of protein in sodium dodecyl sulfate containing medium (SDSEP) decreased, which demonstrated that alkali addition promoted the degree of protein polymerization in the buckwheat noodles. CLSM analysis showed alkali addition produced a tight and continuous protein network in buckwheat noodles. The protein cross-linking induced by alkali improved rheological properties of dough and texture properties of buckwheat noodles., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

To improve the nutritional, physical and flavor properties of wheat bran, yeast and lactic acid bacteria (LAB) were used for fermenting wheat bran in solid state. Appearance properties, nutritional properties, microstructure, hydration properties and flavor of raw bran and fermented bran were evaluated. After treatments, water extractable arabinoxylans were 3-4 times higher than in raw bran. Total dietary fiber and soluble dietary fiber increased after solid state fermentation. Over 20% of phytic acid was degraded. Microstructure changes and protein degradation were observed in fermented brans. Water holding capacity and water retention capacity of fermented brans were improved. Results suggest that solid state fermentation is an effective way to improve the properties of wheat brans., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In this study, changes in fresh noodles during storage were evaluated at the physico-chemical, structural, and molecular levels. An increase in TPC and decrease in L(∗) value mostly occurred during the first 24h; the pH value significantly decreased (P<0.05) and proteins were partially depolymerized with the deterioration of fresh noodles, as evidenced by free amino acid determination and SDS-PAGE. Changes were also detected in the pasting and viscosity properties of the starch component. Moreover, the water sorption isotherm of fresh noodles decreased during storage, and the NMR transverse relaxation peak shifted right with an increased peak area between 10 and 100ms. MRI images showed that with increased storage time, the original structure was damaged and water distribution became non-uniform and migrated to the surface. TPC, pH, and L(∗) value were selected as the visualized parameters to characterize the fresh noodle deterioration, based on the correlation and factor analyses., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Polymerization of gluten and the changes of glutenin macropolymer (GMP) during the production of Chinese steamed bread (CSB) were investigated, providing a theoretical basis to improve and regulate the quality of CSB. Protein extractability and free sulfhydryl (SH) contents increased to some degree during the dough preparation stage, but significantly (P<0.05) decreased during steaming. Remarkable protein aggregates were observed in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) patterns. The microstructure study of the gas cell and the protein network by confocal laser scanning microscopy (CLSM) further revealed the formation of a continuous and three-dimensional gluten network. The loss and recovery of GMP wet weight during dough processing were significant (P<0.05). Glutenin depolymerization negatively correlated with GMP wet weight and the contents of high molecular weight glutenin subunits (HMW-GS) and low molecular weight glutenin subunits (LMW-GS). Gluten polymerization led to a decrease in G' and G″ of GMP while gluten depolymerization induced a slight recovery in G' and G″ of GMP., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Some wheat-based food systems, such as cakes and cookies, include mixtures of gluten and egg white protein (EWP) and are processed under heating conditions. Changes in these proteins during processing can affect the quality of the end product. This study investigated protein polymerization during heating of (mixtures of) wheat gluten and EWP. Chemical changes were studied by size-exclusion high performance liquid chromatography (SE-HPLC), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), thiol (SH) measurement and Fourier transform infrared (FTIR). During heating, protein polymerization was observed in the mixtures of gluten, glutenin, gliadin and EWP according to SE-HPLC profiles and results of SDS-extractable protein. The results of SDS-PAGE profiles of different proteins were in accordance with SE-HPLC. The number of SH groups in the majority of proteins showed a significant decrease, implying that disulfide (SS) bonds contributed to the extractability loss. In addition, changes of secondary structure tested by FTIR indicated protein aggregation., (Copyright © 2015. Published by Elsevier Ltd.)

Based on the critical water content (for noodle deterioration) concluded previously, high-temperature-short-time (HTST; 105-135°C) and medium-temperature-long-time (MTLT; 45-75°C) dehydrations were introduced in this study to produce semi-dried noodles. The effects of HTST and MTLT on the quality parameters of semi-dried noodles, as well as noodle structure, storage stability, and changes in starch and protein components were thoroughly investigated. Differential scanning calorimeter (DSC) and birefringent analysis presented few starch gelatinization (approximately 30%) in HTST dehydrated noodles. Scanning electron microscopy (SEM) images showed more compact noodle surface, with uniform pores in the cross section, probably due to enhanced protein-starch combination after HTST dehydration. Meanwhile, HTST induced protein polymerizations in semi-dried noodles, mainly by -SH-S-S interchange, and resulted in significantly (P<0.05) reduced cooking loss. Furthermore, HTST noodles showed higher microbial and color stability. Shelf-life of dehydrated samples at 120°C was extended to 5days from 1day of the control., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The application of antioxidants has been considered as an important and effective approach against conditions in which oxidative stress occurs. Especially, ferulic acid (FA) is an important antioxidant which exerts potency against cellular damage in the presence of oxidants. In the current study, the resistance effect of FA on hydrogen peroxide (H2O2)-stressed human embryonic kidney 293 cells (HEK293) in vitro was investigated. FA (1 mM) increased HEK293 cells' viability and significantly reduced H2O2-induced cellular apoptosis, which was confirmed with flow cytometry and morphological results. Cell cycle analysis indicated low percentage of sub-G0 population of FA-treated HEK293 cells that confirmed its resistance effect. The FA-treated HEK293 cells followed by H2O2 exposure resulted in decreased ROS levels compared to control (H2O2-treated only). The results indicated that pretreatment of FA on cell prior to H2O2 exposure could significantly improve cell survival and increase catalase (CAT) and superoxide dismutase (SOD) levels. On the other hand, reduction in the levels of MDA and ROS was obvious. It can be concluded that FA may protect HEK293 cells from injury induced by H2O2 through regulation of intracellular antioxidant enzyme activities and cell cycle distribution. The reduction in mitochondrial membrane potential was also inhibited by FA treatment. These results suggested the importance of naturally occurring antioxidants such as FA in therapeutic intervention methodology against oxidative stress-related diseases.

The effect of Lactobacillus plantarum NCU116 on liver function, oxidative stress and lipid metabolism in rats with high fat diet induced non-alcoholic fatty liver disease (NAFLD) was studied. The rats were divided into four groups: the normal diet (ND) group; the high fat diet (HFD) group; and HFD plus L. plantarum NCU116 as two doses (NCU116-L, 10(8) CFU mL(-1); NCU116-H, 10(9) CFU mL(-1)) groups. Treatment of L. plantarum NCU116 for 5 weeks was found to restore liver function and oxidative stress in rats with NAFLD, and decrease the levels of fat accumulation in the liver. In addition, the bacterium significantly reduced endotoxin and proinflammatory cytokines, and regulated bacterial flora in the colon and the expression of lipid metabolism in the liver. These results suggest that possible underlying mechanisms for the beneficial effect of L. plantarum NCU116 on NAFLD may include two pathways of downregulating lipogenesis and upregulating lipolysis and fatty acid oxidation related gene expression.

A newly identified polysaccharide (PSG-1) has been purified from Ganoderma atrum. The study was to investigate the protective effect of PSG-1 on diabetes-induced endothelial dysfunction in rat aorta. Rats were fed a high fat diet for 8 weeks and then injected with a low dose of streptozotocin to induce type 2 diabetes. The diabetic rats were orally treated with PSG-1 for 4 weeks. It was found that administration of PSG-1 significantly reduced levels of fasting blood glucose, improved endothelium-dependent aortic relaxation, increased levels of phosphoinositide 3-kinase (PI3K), phospho-Akt (p-Akt), endothelial nitric oxide synthase (eNOS) and nitric oxide in the aorta from diabetic rats, compared to un-treated diabetics. These results suggested that the protective effects of PSG-1 against endothelial dysfunction may be related to activation of the PI3K/Akt/eNOS pathway., (Copyright © 2014 Elsevier Ltd. All rights reserved.)