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Summary Tofu, a traditional soy‐based food, is widely consumed globally and serves as a significant source of plant protein. The quality of tofu can vary greatly depending on the coagulation process and the type of coagulants used. This study investigated the impact of a compound coagulant, consisting of transglutaminase (TGase) and calcium sulfate (CaSO4), on tofu quality, specifically focusing on pH, yield, water holding capacity (WHC), cooking loss, protein content, and in vitro digestibility. Soymilk was pre‐crosslinked with TGase for different durations (0, 1, 2, and 3 h) before the addition of CaSO4. Results indicated that TGase pre‐treatment significantly improved tofu yield and WHC, with optimal outcomes at 3 and 2 h, respectively. Cooking loss decreased with TGase treatment but increased at the 3‐h mark, suggesting over‐crosslinking. Electrophoresis revealed substantial protein crosslinking with TGase treatment, while in vitro digestion showed enhanced protein digestibility and higher peptide content in TGase‐treated samples. These findings underscore the potential of TGase treatment to enhance tofu's structural integrity and digestibility, offering valuable insights for optimising plant‐based protein processing to improve nutritional quality. [ABSTRACT FROM AUTHOR]

Summary: The development of edible films, which serve as a safe alternative to synthetic polymers by utilising by‐products from the agricultural industry, has become a focus of research as they contribute to the sustainable use of resources. In the present study, quince seed gel (QSG) and whey protein concentrate (WPC) (1:1 w/w) were used as base components to develop edible films using glycerol as a plasticiser. The proteins were sonicated to denature and then the proteins were modified by cross‐linking with the enzyme transglutaminase (TGase). The thickness, moisture content, solubility, permeability and digestibility of each edible films were investigated. In addition to the morphological, mechanical, optical, thermal and structural properties, the edible films were further characterised. The thickness, moisture, water vapour and oxygen permeability and the water solubility of the films were positively influenced by the cross‐linking and the digestibility of proteins decreased with the cross‐linking. A remarkable change in the secondary structures was observed in the FTIR spectra of the films. The stronger networks and their smooth surface of crosslinked films were confirmed by AFM images. The results of this research shows that QSG/WPC films cross‐linked with TGase have potential for use in food packaging systems due to their advantages and may be an attractive alternative to synthetic materials in further studies. [ABSTRACT FROM AUTHOR]

In dairy-based imitation mozzarella cheese (IMC) formulations, intact casein is critical and imparts IMC with a firm and elastic, stringy, melted texture. Rennet casein (RCN) is the desired ingredient to provide intact casein in IMC and is preferred over milk protein concentrate (MPC) and micellar casein concentrate (MCC). Transglutaminase (TGase), a crosslinking enzyme, alters the physical properties of MPC or MCC and may change IMC functionality. The objective of this study was to determine the effect of TGase-crosslinked MPC and MCC powders on the functionality of IMCs. The TGase treatment included TGase at 0.3 (L) and 3.0 (H) units/g of protein and a control (C) with no TGase addition. Each IMC formulation was balanced for constituents and was produced in a Rapid Visco Analyzer (RVA). The MCC or MPC powder with high TGase enzyme in IMC formulation did not form an emulsion. The IMC containing TGase-treated powders had a significantly (p ≤ 0.05) higher RVA-viscosity during manufacture and transition temperature (TT), and a significantly (p ≤ 0.05) lower Schreiber melt test area. The IMC made from MPC (with or without TGase) had lower TT values and Schreiber melt test area as compared with that made from MCC. The TGase-treated MPC and MCC, when used for IMC manufacture, were comparable to IMC manufactured with RCN in texture and some measured melted characteristics. In conclusion, TGase treatment alters the melt characteristics of MCC and MPC in IMC applications. [ABSTRACT FROM AUTHOR]

In the previous work by the same authors, optimisation of sequential application of acid protease and transglutaminase was carried out to achieve Woolmark specification AW-1 for the machine washable care claim, that is, less than 3% total shrinkage. As a result of optimisation, the total warp shrinkage reduced to 2.64% with only 2.82% loss in warp tensile strength. In this work, simultaneous application of acid protease and transglutaminase was explored and optimised using Box–Behnken design of experiment. The optimisation was carried out using two criteria. In the first criterion, the model was used to predict treatment parameters for minimum total warp shrinkage with minimum loss in warp tensile strength. Taking these predicted treatment parameters, wool was treated with acid protease (1%, owf) and transglutaminase (2.8%, owf) at pH ∼5.3 and 50°C for 60 min. After treatment, the total warp shrinkage reduced to only 4.32% with 4.65% loss in warp tensile strength. This was not only higher than the optimised sequential application of both the enzymes but also failed to meet the Woolmark specification for machine washable care claim. So, the second criterion was used in which the prediction was taken for treatment parameters to achieve the minimum total warp shrinkage without any constraints on loss in warp strength. Again, taking these predicted treatment parameters, wool was treated with acid protease (1.3%, owf), transglutaminase (1.6%, owf), pH ∼4.7 at 55°C for 85 min. Under these treatment conditions, the total warp shrinkage reduced to 2.89% with 10.1% loss in warp strength. Furthermore, interaction between the enzymes also plays a role in the outcomes of the treatment. It was evident that there was a loss in transglutaminase activity as a result of acid protease digestion. However, there was no loss in the activity of acid protease, indicating that transglutaminase did not have any negative influence on the activity of acid protease. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fried foods are favored for their unique crispiness, golden color and flavor, but they also face great challenge because of their high oil content, high calories and the existence of compounds such as acrylamide and polycyclic aromatic hydrocarbons. Long‐term consumption of fried foods may adversely affect health. Therefore, it is necessary to explore fried foods with lower oil contents and a high quality to meet the demand. RESULTS: A method of enzyme treatment was explored to investigate the effects of maltogenic amylase (MA), transglutaminase (TG) and bromelain (BRO) on the physicochemical properties of the batter and the quality of fried spring roll wrapper (FSRW). The results showed that the MA‐, TG‐ or BRO‐treated batters had a significant shear‐thinning behavior, especially with an increase in viscosity upon increasing TG contents. FSRW enhanced its fracturability from 419.19 g (Control) to 616.50 g (MA‐6 U g−1), 623.49 g (TG‐0.75 U g−1) and 644.96 g (BRO‐10 U g−1). Meanwhile, in comparison with BRO and MA, TG‐0.5 U g−1 endowed batter with the highest density and thermal stability. MA‐15 U g−1 and TG‐0.5 U g−1 displayed FSRW with uniform and dense pores, and significantly reduced its oil content by 18.05% and 25.02%, respectively. Moreover, compared to MA and TG, BRO‐50 U g−1 improved the flavor of FSRW. CONCLUSION: MA, TG or BRO played a key role in affecting the physicochemical properties of the batter and the quality of FSRW. TG‐0.5 U g−1 remarkly reduced the oil content of FSRW with a great potential in practical application. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A 3-dimensional culture system of keratinocytes achieves cornification as a terminal differentiation that can mimic the formation of stratified epidermis. At the onset of keratinocyte differentiation, air-exposure treatment is essential for promotion. We have previously reported that the stimulation of differentiation is accompanied by downregulation of the transcriptional activity of the hypoxia-inducible factor (HIF) and also found that rocking treatment of cultured keratinocytes in the submerged condition restored their differentiation. A comparative study of cultured keratinocytes with and without rocking was then carried out to investigate the characteristics of the recovered differentiation by morphological and biochemical analyses. In addition, transcriptome analysis revealed the expected similar pattern between air-exposed and rocking cultures, including HIF-regulating transcripts. Furthermore, the promotive effect of rocking treatment was impaired under hypoxic culture conditions (1% O2). We showed that the restored promotion of differentiation by rocking culture is mainly due to the abrogation of transcriptional events by hypoxia. [ABSTRACT FROM AUTHOR]

The poor thermal stability of lactoferrin (LF) hinders its bioavailability and use in commercial food products. To preserve LF from thermal denaturation, complexation with other biopolymers has been studied. Here we present the complex formation conditions, structural stability, and functional protection of LF by α‐lactalbumin (α‐LA). The formation of the LF–α‐LA complexes was dependent on pH, mass ratio, and ionic strength. Changing the formation conditions and cross‐linking by transglutaminase impacted the turbidity, particle size, and zeta‐potential of the resulting complexes. Electrophoresis, Fourier‐transform infrared spectroscopy, and circular dichroism measurements suggest that the secondary structure of LF in the LF–α‐LA complex was maintained after complexation and subsequent thermal treatments. At pH 7, the LF–α‐LA complex protected LF from thermal aggregation and denaturation, and the LF retained its functional and structural properties, including antibacterial capacity of LF after thermal treatments. The improved thermal stability and functional properties of LF in the LF–α‐LA complex are of interest to the food industry. [ABSTRACT FROM AUTHOR]

This study explored the changes in cross-linking of low-salt myosin mediated by microbial transglutaminase (MTGase) under high intensity ultrasound (HIU). HIU activated the fish endogenous transglutaminase by 14.11%. Meanwhile, HIU induced the conformational changes in low-salt myosin with decrease of α-helix and increase of β-sheet structures. At 0.1 mol/L salt, compared to solely treated MTGase/solely treated myosin, the most ε-(γ-Glu)-Lys bonds were formed in HIU-treated MTGase + myosin, evidenced by the lowest solubility. Correspondingly, the G' showed the highest increase rate. Consequently, the samples formed regular and continuous protein matrix structures. Specifically, the microstructures of HIU-treated MTGase + myosin samples at 0.1 mol/L salt were even more compact than those of control samples at 0.3 mol/L salt. Besides, HIU-treated MTGase + myosin improved the water holding capacity by 18.28%. In summary, HIU promoted the cross-linking between low-salt myosin mediated by MTGase through activating the enzyme, improving substrate dispersion, or both, with the largest improvement degree observed for HIU-treated MTGase + myosin group. [ABSTRACT FROM AUTHOR]

The growing demand for alternative sources of non-animal proteins has stimulated research in this area. Mushrooms show potential in the innovation of plant-based food products. In this study, the aim was to develop prototype fish fillets analogues from Pleurotus ostreatus mushrooms applying enzymatic treatment (β-glucanase and transglutaminase-TG). A Plackett–Burman 20 experimental design was used to optimize forty variables. Oat flour (OF) exerted a positive effect on the hardness and gumminess texture parameters but a negative effect on cohesiveness and resilience. Soy protein isolate (SPI) exhibited a positive effect on elasticity, gumminess and chewiness, while acacia gum had a negative effect on elasticity, cohesiveness and resilience. After sensory analysis the assay with 1% cassava starch, 5% OF, 5% SPI, 0.1% transglutaminase (240 min/5 °C), 1% coconut oil, 1% soybean oil, 0.2% sodium tripolyphosphate, 0.6% β-glucanase (80 °C/10 min) and without β-glucanase inactivation was found to exhibit greater similarity to fish fillet. The classes hydrocarbons, alcohols and aldehydes are the predominant ones in aromatic profile analysis by chromatography and electronic nose. It is concluded that a mushroom-based analogue of fish fillet can be prepared using enzymatic treatment with TG. [ABSTRACT FROM AUTHOR]

Fish gelatin is a promising polymer for creating plastics derived from agro-industrial waste, offering a sustainable alternative to single-use plastics. This research aimed to develop fish gelatin films that can be used to replace conventional single-use plastics employed in food packaging. Specifically, our focus was on reducing the high hydrophilic behavior of fish gelatin films which limits their possible applications. To address this, mono-, bi-, and tri- layer films were fabricated from fish gelatin and amylopectin. The fish gelatin was cross-linked with the enzyme transglutaminase to reduce its hydrophilicity achieving two levels of cross-linking: 40 ± 2%, and 65 ± 4%. Micrographs confirmed crack-free films and bilayer/trilayer formation. The cross-linked films exhibited reduced solubility: about 30% in monolayer and 40–67% in bilayer and trilayer films compared to pure protein films. Regarding the water vapor transmission rate, the highly cross-linked trilayer film displayed a value of 0.95 g/m2 h which is significantly lower than pure protein films (2.89 g/m2 h) and amylopectin films (9.37 g/m2 h). Additionally, Young's modulus and the thermal stability were improved with the lamination. These results suggest an effective method for manufacturing films from fish waste, which could contribute to a circular economy for the fishing industry. Enhanced water resistance also makes the films potentially suitable for sustainable biopolymer-based active food packaging. [ABSTRACT FROM AUTHOR]

Transglutaminase (TGase)-catalyzed crosslinking has gained substantial traction as a novel strategy for reducing allergenic risk in food proteins, particularly within the realm of hypoallergenic food production. This study explored the impact of TGase crosslinking on conformational changes in a binary protein system composed of soy protein isolate (SPI) and sodium caseinate (SC) at varying mass ratios (10:0, 7:3, 5:5, 3:7 (w/w)). Specifically, the immunoglobulin E (IgE) binding capacity of soy proteins within this system was examined. Prolonged TGase crosslinking (ranging from 0 h to 15 h) resulted in a gradual reduction in IgE reactivity across all SPI-SC ratios, with the order of IgE-binding capability as follows: SPI > SPI5-SC5 > SPI7-SC3 > SPI3-SC7. These alterations in protein conformation following TGase crosslinking, as demonstrated by variable intrinsic fluorescence, altered surface hydrophobicity, increased ultraviolet absorption and reduced free sulfhydryl content, were identified as the underlying causes. Additionally, ionic bonds were found to play a significant role in maintaining the structure of the dual-protein system after crosslinking, with hydrophobic forces and hydrogen bonds serving as supplementary forces. Generally, the dual-protein system may exhibit enhanced efficacy in reducing the allergenicity of soy protein. [ABSTRACT FROM AUTHOR]

Mammalian transglutaminases, a family of Ca2+-dependent proteins, are implicated in a variety of diseases. For example, celiac disease (CeD) is an autoimmune disorder whose pathogenesis requires transglutaminase 2 (TG2) to deamidate select glutamine residues in diet-derived gluten peptides. Deamidation involves the formation of transient γ-glutamyl thioester intermediates. Recent studies have revealed that in addition to the deamidated gluten peptides themselves, their corresponding thioester intermediates are also pathogenically relevant. A mechanistic understanding of this relevance is hindered by the absence of any structure of Ca2+-bound TG2. We report the X-ray crystallographic structure of human TG2 bound to an inhibitory gluten peptidomimetic and two Ca2+ ions in sites previously designated as S1 and S3. Together with additional structure-guided experiments, this structure provides a mechanistic explanation for how S1 regulates formation of an inhibitory disulfide bond in TG2, while also establishing that S3 is essential for γ-glutamyl thioester formation. Furthermore, our crystallographic findings and associated analyses have revealed that i) two interacting residues, H305 and E363, play a critical role in resolving the thioester intermediate into an isopeptide bond (transamidation) but not in thioester hydrolysis (deamidation); and ii) residues N333 and K176 stabilize preferred TG2 substrates and inhibitors via hydrogen bonding to nonreactive backbone atoms. Overall, the intermediate-state conformer of TG2 reported here represents a superior model to previously characterized conformers for both transition states of the TG2-catalyzed reaction. [ABSTRACT FROM AUTHOR]

Previously, we showed that water extract (soymilk, except pH was increased to 8 from 6.5) of whole soybean could be used directly as a raw material for producing edible soy films by deposition of the film‐forming solution (soy extract with enhancers). However, the strength of such soy films needed improvement because they were weak. The purpose of this study was to investigate how transglutaminase (TG) cross‐linking reactions and film enhancers, including pectin (low‐ and high‐methoxyl pectin), whey protein isolate (WPI), and soy protein isolate (SPI), improve the physical properties of soy films. Soy films prepared with TG had tensile strength (TS) of 3.01 MPa and puncture strength (PS) of 0.78 MPa, which were higher by as much as 51% and 30% than that of soy films without TG treatment, respectively. Pectin showed significant effects on the mechanical properties of TG‐added soy films in terms of TS, PS, and % elongation. On the other hand, only TS and PS were increased by the addition of WPI or SPI. Heat curing had a significant effect on soy film's physical properties. TG treatment significantly reduced film solubility when soaked in water and various levels of acid (vinegar) and base (baking soda) solutions. Under the experimental conditions of 35 unit TG and 28 min of reaction, the degrees of cross‐linking were evidenced by the disappearance of individual protein subunits, except the basic subunit of glycinin, and the reduction of 21% of lysine residues of the proteins. Highlights: Edible soy films were made with transglutaminase and about 21% lysine cross‐linked.The mechanical strength of soy films was increased by incorporating film enhancers.Transglutaminase enhanced the mechanical properties of soy films. [ABSTRACT FROM AUTHOR]

Plant-based protein is considered a sustainable protein source and has increased in demand recently. However, products containing plant-based proteins require further modification to achieve the desired functionalities akin to those present in animal protein products. This study aimed to investigate the effects of enzymes as cross-linking reagents on the physicochemical and functional properties of hybrid plant- and animal-based proteins in which lupin and whey proteins were chosen as representatives, respectively. They were hybridised through enzymatic cross-linking using two laccases (laccase R, derived from Rhus vernicifera and laccase T, derived from Trametes versicolor) and transglutaminase (TG). The cross-linking experiments were conducted by mixing aqueous solutions of lupin flour and whey protein concentrate powder in a ratio of 1:1 of protein content under the conditions of pH 7, 40 °C for 20 h and in the presence of laccase T, laccase R, or TG. The cross-linked mixtures were freeze-dried, and the powders obtained were assessed for their cross-linking pattern, colour, charge distribution (ζ-potential), particle size, thermal stability, morphology, solubility, foaming and emulsifying properties, and total amino acid content. The findings showed that cross-linking with laccase R significantly improved the protein solubility, emulsion stability and foaming ability of the mixture, whereas these functionalities were lower in the TG-treated mixture due to extensive cross-linking. Furthermore, the mixture treated with laccase T turned brownish in colour and showed a decrease in total amino acid content which could be due to the enzyme’s oxidative cross-linking mechanism. Also, the occurrence of cross-linking in the lupin and whey mixture was indicated by changes in other investigated parameters such as particle size, ζ-potential, etc., as compared to the control samples. The obtained results suggested that enzymatic cross-linking, depending on the type of enzyme used, could impact the physicochemical and functional properties of hybrid plant- and animal-based proteins, potentially influencing their applications in food. [ABSTRACT FROM AUTHOR]

Protein-based emulsion gels have tunable viscoelasticity that can be applied to improve the stability of bioactive ingredients. As the by-product of rice processing, rice bran protein (RBP) has high nutritional value and good digestibility, exhibiting unique value in the development of hypoallergenic formula. In this study, the effect of transglutaminase (TGase) cross-linking on the physicochemical properties of RBP emulsion gels was investigated. To improve the stability of curcumin against environmental stress, the entrapment efficiency and stability of curcumin in the emulsion gel systems were also evaluated. The results indicated that TGase increased the viscoelastic modulus of RBP emulsion gels, resulting in a solid-like structure. Moreover, the entrapment efficiency of curcumin was increased to 93.73% after adding TGase. The thermal stability and photo-stability of curcumin were enhanced to 79.54% and 85.87%, respectively, compared with the sample without TGase addition. The FTIR results showed that TGase induced the cross-linking of protein molecules and the secondary structure change in RBP. Additionally, SEM observation confirmed that the incorporation of TGase promoted the formation of a compact network structure. This study demonstrated the potential of RBP emulsion gels in protecting curcumin and might provide an alternative strategy to stabilize functional ingredients. [ABSTRACT FROM AUTHOR]

This study investigated the effects of high-pressure processing (HPP; 600 MPa/15 min) and microbial transglutaminase-catalyzed (MTG; 30 U·g of protein−1) crosslinking on the concentration of dissolved proteins (SOL), free sulfhydryl groups (SH), surface hydrophobicity (H0), and viscosity of pea protein isolates (PPI) at different concentrations (1–13%; w/v). The SOL increased by increasing protein concentration (max. 29%). MTG slightly affected SOL. HPP decreased SOL with increasing protein concentration, and the combination MTG + HPP resulted in a lower SOL than HPP alone. The concentration of SH in untreated PPI increased with increasing protein concentration, reaching a maximum of 8.3 μmol·mg prot−1. MTG increased SH at higher protein concentrations. HPP lowered SH, but its concentration increased by increasing protein concentration. HPP + MTG offset the effect of MTG, yielding lower SH. MTG did not affect H0 at 1% concentration but increased it for concentrations from 3–5%, and there was a decrease with 7–9%. HPP increased H0 up to 37% for intermediate protein concentrations but did not affect it at higher concentrations. MTG + HPP decreased H0 at all protein concentrations. The viscosity of the dispersions increased with protein concentration. HPP increased the viscosity of the dispersions for concentrations above 7%, while MTG only caused changes above 9%. Combined MTG + HPP resulted in viscosity increase. The results underscore the opportunity for innovative development of high-protein products with improved properties or textures for industrial application.

In this study, the effect of alginate and/or transglutaminase (TGase) in combination with ultrasonic treatment on the heat-induced gel quality, water-holding capacity (WHC) and myosin conformational changes of unwashed surimi was investigated. The results showed that the addition of trehalose (4.5%, m/m) and/or TGase (0.5%, m/m) together with ultrasonic treatment increased the gel strength by 35.11%−169.25%. Trehalose prevented protein unfolding while TGase had the opposite effect. However, ultrasonic treatment inhibited the catalytic activity of TGase, thereby reducing the gel strength to 4 737.23 g·mm, decreasing the relative content of free water to 19.52%, and alleviating excessive cross-linking of proteins. Furthermore, ultrasonic promoted protein unfolding even under the protection of trehalose. When added simultaneously, trehalose and TGase weakened their respective effects on protein structure.

Pulmonary fibrosis is an interstitial scarring disease of the lung characterized by poor prognosis and limited treatment options. Tissue transglutaminase 2 (TG2) is believed to promote lung fibrosis by crosslinking extracellular matrix components and activating latent TGFβ. This study assessed physiologic pulmonary function and metabolic alterations in the mouse bleomycin model with TG2 genetic deletion. TG2‐deficient mice demonstrated attenuated the fibrosis and preservation of lung function, with significant reduction in elastance and increases in compliance and inspiratory capacity compared to control mice treated with bleomycin. Bleomycin induced metabolic changes in the mouse lung that were consistent with increased aerobic glycolysis, including increased expression of lactate dehydrogenase A and increased production of lactate, as well as increased glutamine, glutamate, and aspartate. TG2‐deficient mice treated with bleomycin exhibited similar metabolic changes but with reduced magnitude. Our results demonstrate that TG2 is required for a typical fibrosis response to injury. In the absence of TG2, the fibrotic response is biochemically similar to wild‐type, but lesions are smaller and lung function is preserved. We also show for the first time that profibrotic pathways of tissue stiffening and metabolic reprogramming are interconnected, and that metabolic disruptions in fibrosis go beyond glycolysis. [ABSTRACT FROM AUTHOR]

Human transglutaminase 1 (TG1) modulates skin development, while its involvement in diseases remains poorly understood, necessitating comprehensive exploration of its substrate interactions. To study the substrate profile of TG1, an in vitro selection system based on cDNA display technology was used to screen two peptide libraries with mutations at varying distance from the reactive glutamine. Next-generation sequencing and bioinformatics analysis of the selected DNA pools revealed a detailed TG1 substrate profile, indicating preferred and non-preferred amino acid sequences. The peptide sequence, AEQHKLPSKWPF, was identified showing high reactivity and specificity to TG1. The position weight matrix calculated from the per amino acid enrichment factors was employed to search human proteins using an in-house algorithm, revealing six known TG1 substrate proteins with high scores, alongside a list of candidate substrates currently under investigation. Our findings are expected to assist in future medical diagnoses and development of treatments for skin disorders. [ABSTRACT FROM AUTHOR]

Transglutaminases (TGMs) cross-link proteins by introducing covalent bonds between glutamine and lysine residues. These cross-links are essential for epithelial cornification which enables tetrapods to live on land. Here, we investigated which evolutionary adaptations of vertebrates were associated with specific changes in the family of TGM genes. We determined the catalog of TGMs in the main clades of vertebrates, performed a comprehensive phylogenetic analysis of TGMs, and localized the distribution of selected TGMs in tissues. Our data suggest that TGM1 is the phylogenetically oldest epithelial TGM, with orthologs being expressed in the cornified teeth of the lamprey, a basal vertebrate. Gene duplications led to the origin of TGM10 in stem vertebrates, the origin of TGM2 in jawed vertebrates, and an increasing number of epithelium-associated TGM genes in the lineage leading to terrestrial vertebrates. TGM9 is expressed in the epithelial egg tooth, and its evolutionary origin in stem amniotes coincided with the evolution of embryonic development in eggs that are surrounded by a protective shell. Conversely, viviparous mammals have lost both the epithelial egg tooth and TGM9. TGM3 and TGM6 evolved as regulators of cornification in hair follicles and underwent pseudogenization upon the evolutionary loss of hair in cetaceans. Taken together, this study reveals the gain and loss of vertebrate TGM genes in association with the evolution of cornified skin appendages and suggests an important role of TGM9 in the evolution of amniotes. [ABSTRACT FROM AUTHOR]

Silver Carp (SC) is an under-utilized, invasive species in North American river systems. In this study, the synergistic effects of manufactured Microfiber (MMF), Transglutaminase (TG), and chicken skin collagen (CLG)) to enhance surimi gel quality from frozen SC were studied. The gel strength, textural properties, rheological properties, water-holding capacity (WHC), water mobility, microstructure, and protein composition of the gel samples were determined to assess the impact of the additives individually and synergistically. The results suggested that TG had the most pronounced effect on the surimi gel properties by promoting protein cross-linking. Synergistic effects between TG, MMF, and CLG can bring effective gel property enhancement larger than the individual effect of each additive alone. With the established response-surface models, the combination of CLG and MMF can be optimized to produce surimi gels with less TG but comparable in properties to that of the optimal result with high TG usage. The findings of this study provided a technical foundation for making high-quality surimi gel products out of frozen-stored SC with synergistic utilization of additives, which could serve as guidelines for the industrial development of new surimi products. [ABSTRACT FROM AUTHOR]

This study investigated the effects of high-pressure processing (HPP; 600 MPa/15 min) and microbial transglutaminase-catalyzed (MTG; 30 U·g of protein−1) crosslinking on the concentration of dissolved proteins (SOL), free sulfhydryl groups (SH), surface hydrophobicity (H0), and viscosity of pea protein isolates (PPI) at different concentrations (1–13%; w/v). The SOL increased by increasing protein concentration (max. 29%). MTG slightly affected SOL. HPP decreased SOL with increasing protein concentration, and the combination MTG + HPP resulted in a lower SOL than HPP alone. The concentration of SH in untreated PPI increased with increasing protein concentration, reaching a maximum of 8.3 μmol·mg prot−1. MTG increased SH at higher protein concentrations. HPP lowered SH, but its concentration increased by increasing protein concentration. HPP + MTG offset the effect of MTG, yielding lower SH. MTG did not affect H0 at 1% concentration but increased it for concentrations from 3–5%, and there was a decrease with 7–9%. HPP increased H0 up to 37% for intermediate protein concentrations but did not affect it at higher concentrations. MTG + HPP decreased H0 at all protein concentrations. The viscosity of the dispersions increased with protein concentration. HPP increased the viscosity of the dispersions for concentrations above 7%, while MTG only caused changes above 9%. Combined MTG + HPP resulted in viscosity increase. The results underscore the opportunity for innovative development of high-protein products with improved properties or textures for industrial application. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Food allergies are a growing concern worldwide, with soy proteins being important allergens that are widely used in various food products. This study investigated the potential of transglutaminase (TGase) and lactic acid bacteria (LAB) treatments to modify the allergenicity and structural properties of soy protein isolate (SPI), aiming to develop safer soy‐based food products.Treatment with TGase, LAB or their combination significantly reduced the antibody reactivity of β‐conglycinin and the immunoglobulin E (IgE) binding capacity of soy protein, indicating a decrease in allergenicity. TGase treatment led to the formation of high‐molecular‐weight aggregates, suggesting protein crosslinking, while LAB treatment resulted in partial protein hydrolysis. These structural changes were confirmed by Fourier transform infrared spectroscopy, which showed a decrease in β‐sheet content and an increase in random coil and β‐turn contents. In addition, changes in intrinsic fluorescence and ultraviolet spectroscopy were also observed. The alterations in protein interaction and the reduction in free sulfhydryl groups highlighted the extensive structural modifications induced by these treatments.The synergistic application of TGase and LAB treatments effectively reduced the allergenicity of SPI through significant structural modifications. This approach not only diminished antibody reactivity of β‐conglycinin and IgE binding capacity of soy protein but also altered the protein's primary, secondary and tertiary structures, suggesting a comprehensive alteration of SPI's allergenic potential. These findings provide a promising strategy for mitigating food allergy concerns and lay the foundation for future research on food‐processing techniques aimed at allergen reduction. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This review describes a 50-year-long research study on the characteristics of Helianthus tuberosus L. tuber dormancy, its natural release and programmed cell death (PCD), as well as on the ability to change the PCD so as to return the tuber to a life program. The experimentation on the tuber over the years is due to its particular properties of being naturally deficient in polyamines (PAs) during dormancy and of immediately reacting to transplants by growing and synthesizing PAs. This review summarizes the research conducted in a unicum body. As in nature, the tuber tissue has to furnish its storage substances to grow vegetative buds, whereby its destiny is PCD. The review's main objective concerns data on PCD, the link with free and conjugated PAs and their capacity to switch the destiny of the tuber from a program of death to one of new life. PCD reversibility is an important biological challenge that is verified here but not reported in other experimental models. Important aspects of PA features are their capacity to change the cell functions from storage to meristematic ones and their involvement in amitosis and differentiation. Other roles reported here have also been confirmed in other plants. PAs exert multiple diverse roles, suggesting that they are not simply growth substances, as also further described in other plants. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study aimed to enhance Hatay cheese texture using microbial transglutaminase enzyme (mTG). Cheeses were manufactured using milk treated with mTG for different durations (30, 45 and 60 min) and assessed over 60 days. Longer treatment increased yield (18.79–20.81%) and hardness but reduced springiness. Composition, proteolysis and adhesiveness remained unaffected. Electrophoresis showed β‐casein and αs1‐casein declines during storage, with minor changes in αs1‐casein's breakdown product. Microbial transglutaminase enzyme created a denser protein network, visible in SEM, resulting in a compact structure. Sensory analysis favoured the 60‐min treatment. Overall, mTG improved Hatay cheese quality by modifying texture without major compositional changes. [ABSTRACT FROM AUTHOR]

The development of hydrolyzed lactose powder products involves technological, sensory, and nutritional challenges (adhesion in the drying chamber, browning of the powder, and formation of Maillard reaction products). Recent studies have analyzed the use of transglutaminase (TGase) to reduce product adhesion in dryers and the intensity of the Maillard reaction. This study aimed to evaluate the application of TGase to powdered dairy products with and without hydrolyzed lactose. Skimmed milk powder was dried under four different treatments with three replicates resulting in 12 products (Treatment 1 skimmed milk powder; Treatment 2 skimmed milk powder with lactase; Treatment 3 skimmed milk powder with TGase; Treatment 4 skimmed milk powder with lactase and TGase). The product retention capacity in the equipment; compositional, physicochemical, and morphological attributes; particle size; and Maillard reaction markers were analyzed. The use of TGase did not affect drying conditions or powder processing. Transglutaminase increased the particle size of the products without altering their bimodal conformation. The color of the product was not modified regardless of whether TGase was added. In the hydrolyzed product with added TGase, the HMF value increased (6–21 times). The use of TGase did not affect the hydrolysis of lactose, and a decrease in the intensity of the casein bands (glutamine-lysine crosslinking) was observed by electrophoresis. This study led to new hypotheses and possibilities for future studies to elucidate the influence of TGase addition to powdered dairy products. [ABSTRACT FROM AUTHOR]

Antifreeze peptides have become effective antifreeze agents for frozen products, but their low quantity of active ingredients and high cost limit large-scale application. This study used the glycosylation of fish collagen peptides with glucosamine hydrochloride catalyzed by transglutaminase to obtain a transglutaminase-catalyzed glycosylation product (TGP) and investigate its antifreeze effect on tilapia. Compared with the blank group, the freshness (pH value of 6.31, TVB-N value of 21.7 mg/100 g, whiteness of 46.28), textural properties (especially hardness and elasticity), and rheological properties of the TGP groups were significantly improved. In addition, the protein structures of the samples were investigated using UV absorption and fluorescence spectroscopy. The results showed that the tertiary structure of the TGP groups changed to form a dense polymer. Therefore, this approach can reduce the denaturation and decomposition of muscle fibers and proteins in fish meat more effectively and has a better protective effect on muscle structure and protein aggregation, improving the stability of fish meat. This study reveals an innovative method for generating antifreeze peptides by enzymatic glycosylation, and glycosylated fish collagen peptide products can be used as new and effective green antifreeze agents in frozen foods. [ABSTRACT FROM AUTHOR]

In recent years, protein nanoparticles have been well considered in the production of Pickering emulsions and low-calorie foods, but few of them have been introduced. Therefore, finding new sources of nanoparticles and modifying their physical and thermal properties is very important. In this paper, the effect of various levels of microbial transglutaminase (mTG) (0–30 μg/g of sample) and ultrasound time (0–20 min) on properties of nanoparticles prepared with Amaranth Protein Isolate (API) were investigated and optimal levels were achieved by Response surface methodology. Based on the data analysis, ultrasound had a significant effect on tested properties, so that with an increase in ultrasound time, the particle size became smaller. Excluding Zeta potential, all nanoparticles properties were influenced by the interaction of ultrasound and mTG. The enzyme had a great impact (P < 0.001) on Nanoparticles characteristics except for Glass Transition Temperature. However, depending on enzyme content, changeable behaviors in particle size, particle size distribution and denaturation temperature were detected which is generally associated with the changes in the structure and formation of covalent bonds with the function of mTG. Scanning electron microscopy of FE-SEM showed spherically synthesized nanoparticles with a size between 53 to 155 nm. This seems to facilitate the use of ultrasound reaction between nanoparticles and biopolymer matrix. Consequently, the optimized levels of 16.7 min for ultrasound and 9.47 micg/g for mTG resulted in generating a product with the considered characteristics. This novel and edible amaranth-based Nanoparticles could be suggested for Pickering emulsion preparation. [ABSTRACT FROM AUTHOR]

Summary: In this study, β‐conglycinin was treated with transglutaminase (TGase) and glucono‐δ‐lactone (GDL) to meticulously examine the resulting changes in both antigenicity and structural attributes. The findings elucidated a significant reduction (P < 0.05) in the antigenicity of β‐conglycinin to 72.1% and 77.5% after the modified treatment employing TGase alone or in conjunction with GDL, respectively, in contrast to the untreated samples. Electrophoretic analysis showed a decrease in the density of 7S α, 7S α′, and 7S β, indicating the formation of high molecular weight protein aggregates because of the catalytic effect of TGase. Additionally, the simultaneous application of TGase and GDL induced modifications in the structural configuration of β‐conglycinin, as evidenced by a decrease in intrinsic fluorescence intensity, an augmentation in surface hydrophobicity, and a transition from β‐sheet to β‐turn and random coil structures. These observed alterations suggest that the decline in antigenicity is intricately linked to conformational changes, potentially influencing the exposure of antigenic epitopes. Overall, this study holds significant theoretical and practical implications for the development of hypoallergenic soy products and the enhancement of food safety. [ABSTRACT FROM AUTHOR]

BACKGROUND: The use of emulsion gels to protect and deliver probiotics has become an important topic in the food industry. This study used transglutaminase (TGase) to regulate ovalbumin (OVA) to prepare a novel emulsion gel. The effects of OVA concentration and the addition of TGase on the microstructure, rheological properties, water‐holding capacity, and stability of the emulsion gels were investigated. RESULTS: With the addition of TGase and the increasing OVA, the particle size of the emulsion gels decreased significantly (P < 0.05). The gels with TGase exhibited greater water holding, hardness, and chewiness to some extent by forming a more uniform and stable system. After simulated digestion, the survival rate of Bifidobacterium lactis embedded in OVA emulsion gels improved significantly in comparison with the oil–water mixture as a result of the protective effect of the emulsion gel encapsulation. CONCLUSION: By increasing the OVA content and adding TGase, the rheological characteristics, stability, and encapsulation capability of the OVA emulsion gel could be enhanced, providing a theoretical basis for the use of emulsion gels to construct probiotic delivery systems. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the influence of enzymatic treatment with transglutaminase on gelatin films derived from Tambaqui skin. The gelatin was extracted through acid extraction, characterized, and subjected to enzymatic crosslinking with transglutaminase at concentrations of 1%, 2%, and 3% (w/w). The optimal conditions for film production were determined based on gelatin Bloom strength. The films were characterized according to physical, chemical, mechanical, barrier, and thermal properties. The extracted gelatin exhibited a molecular weight distribution of 52 kDa, a viscosity of 2.87 cP, and a Bloom strength of 62.71 g. The Gly–Pro–Hyd content accounted for around 31.72% of the total amino acids. The addition of 3% (w/w) transglutaminase significantly increased the gelatin Bloom strength from 62.71 to 101.6 g. However, transglutaminase crosslinking had no significant effect on film thickness and mechanical properties. On the other hand, it did lead to a significant reduction in solubility from 97.57 to 74.29% and water vapor permeability from 10.28 to 9.54 g.mm/m2.d.kPa. FTIR and TGA analyses suggest no significant alterations in the functional groups or degradation events of the gelatin films. Overall, the enzymatic treatment showed promise in reducing the solubility and water vapor permeability of Tambaqui skin gelatin films. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Transglutaminase (TGase), an efficient protein cross-linking agent, has been widely applied in the meat industry to enhance the quality of meat products by modifying the structure of myofibrillar protein (MP) and consequently improving the heat-induced gel properties of MP. Meanwhile, degree of cross-linking (DCL) is the most important indicator to evaluate the cross-linking effect catalyzed by TGase, which is of particular importance for analyzing the effect of covalent cross-linking catalyzed by TGase on the conformational characteristics, physicochemical properties, and gel properties of MP. Therefore, this article systematically reviews the influential factors of DCL in TGase-catalyzed covalent cross-linking of MP, and dissects the molecular mechanisms of the effect of exogenous additives and novel processing technologies on TGase-catalyzed cross-linking. The aim of this article is to establish the relationship among structural modification, molecular mechanism and quality improvement for TGase-modified MP, which will provide innovative theoretical and technical support for the development of new types of meat products.

IntroductionDoogh is a fermented dairy product that is produced by blending yogurt with water and some salt. This fermented beverage is widely consumed as a refreshing drink in Iran and other Middle East countries. Doogh is a source of calcium needed by the body on a daily basis and contains B vitamins that are effective in the health and strength of teeth and bones. In addition, doogh contains a low percentage of fat, which makes it a diet drink. Whey Protein Concentrate (WPC) is a product contains 25 to 89% protein and different amounts of lactose, fat and minerals. Due to the functional properties of whey protein and its nutritional value; whey protein is widely used in dairy products. The development of cross-linking bonds between protein chains by enzymes is very important today. Enzyme cross-linking of proteins can affect some of their functional properties such as solubility, water absorption, rheological and emulsifying properties. One of the most widely used enzymes in the food industry is the transglutaminase enzyme. In this study the effects of WPC in three levels (0%,1% and 2%) and the transglutaminase enzyme in two levels (0 and 1 unit per gram of milk protein) in two method of dough preparation (adding water to yogurt and fermented milk diluted with water) on rheological characteristics, and microstructure of doogh were studied. Material and MethodsRaw milk was provided by Pegah Khorasan Company, WPC from Multi Company) Mashhad (and Trans glutaminease enzyme from BDF Company of Spain. WPC was first added to milk at 45 ̊ C at three levels of zero, 1 and 2%.The milk samples were then pasteurized at 85 ̊ C for 30 min. After lowering the temperature to 45 ̊ C, the enzymatic operation was performed at two levels of zero and one unit (per gram of protein).To complete the enzyme function, the samples were incubated for 180 minutes at 45 ̊ C. Then a temperature of 90 ̊ C was applied for 1 minute to inactivate the enzyme. The samples were then cooled to 45 ̊ C. At this stage, the samples were divided into two parts. In one part of the samples; milk was diluted with water in a ratio of 6% of the total dry matter for direct production of doogh. After adding the starter, the samples were transferred to an incubator and hold at 43-42 ̊ C, until the pH reaches about 4.1.Thefermented samples were then transferred to a refrigerator. In the second part, starter was added to milk to produce yogurt; after adding starter, the mix was transferred to an incubator and hold at 43-42 ̊ C, until the pH reaches about 4.1. Doogh was produced by diluting yogurt with waterto givethe final product with 6% of total dry matter. Results and Discussion In both production methods, in samples treated only with WPC, the average particle size increased with increasing WPClevel. In both methods, the production of only enzymatically treated samples led to the formation of smaller particles with a more uniform shape and distribution. In samples of doogh produced by both production methods, WPC and transglutaminase enzyme changed the flow characteristics of doogh to non-Newtonian behavior. Samples made directly from milk had significantly higher viscosity than samples made from yogurt. In samples without enzymatic treatment, the microstructure was smooth and homogeneous with smaller particles than other samples. These particles settle very quickly. In the samples where WPC treatment was applied, the amount of large particles and non-uniformity increase with increasing WPC level. The distribution of particles in samples made directly from milk was more regular than samples made from yogurt.

The effects of different concentrations of ε-Poly-lysine (ε-PL: 0.005%, 0.01%, 0.02%, 0.04%, and 0.06%) on the marine fish-egg white protein compound gels, treated with 0.4% TGase induced cross-linking were systematically investigated under low salt and phosphorus-free conditions (0.5% NaCl). The results showed the combination of ε-PL and TGase had a synergistic effect on improving sectional gel properties of composite surimi samples. Wherein the rheological, LF-NMR, and SEM results confirmed that the addition of ε-PL based on 0.4% TGase significantly improved the gel strength (to the highest value: 781.63 g·cm), apparent viscosity, and G 'value of the composite surimi sample, as well as reduced the internal water fluidity of surimi, accompanied by the emergence of a more dense and uniform gel network structure. Notably, ε-PL treatment significantly inhibited fat oxidation in the compound surimi gel and the degree of inhibition was proportional to its addition (decreased from 2.03 to 1.67 mg·kg−1). However, the addition of a small amount (0.005%) or an excessive amount (0.06%) of ε-PL on the gel properties of composite surimi samples witnessed the negative effects of the changes in the internal water distribution state and the cooking loss. To sum up, moderate ε-PL (0.04%) treatment combined with TGase induction can maximize the performance of mixed surimi gel and inhibit fat oxidation. The research results supply a diverse perspective and theoretical basis for the development of 'low salt and no phosphorus' surimi product ingredients.

Transglutaminase (TGase) can catalyze the crosslinking within or between protein molecules, improving the structural and functional properties of proteins. It has been widely used in artificial meat, yogurt products, flour products and other foods. In this study, a high yield TGase strain was screened from fermented soybean, and it was identified as the Bacillus amyloliquefaciens XCT-09. Then, the transglutaminase (X9Tgl) from XCT-09 was expressed in Escherichia coli BL21(DE3), and the enzyme activity of purified X9Tgl reached 5.73 U/mg. Subsequently, the catalytic mechanism of X9Tgl was elucidated, and the X9Tgl contained the active center of E115, C116 and E187, as well as the substrate binding sites W149 and F69. Furthermore, this study characterized the enzymatic properties of X9Tgl, and the optimal catalytic temperature and pH were 60 °C and 6, respectively. Moreover, X9Tgl exhibited stronger thermal stability and pH tolerance than STG, and it was not inhibited by the majority of metal ions. This study successfully identified a X9Tgl with high thermal stability, and pH tolerance, which provided a potential TGase resource for application in the food and medicine fields.

The development of soybean-based analog rice is a potential alternative to rice because of its high protein content. However, the soybean-based analog rice has poor physical properties during cooking, so improvements are required. This research aimed to investigate the effects of corn starch and transglutaminase (TGase) additions on the physicochemical properties of soybean-based analog rice. Variation of soybean flour to corn starch ratio (100:0, 80:20, 60:40, and 40:60) and TGase concentrations (0 %, 0.5 %, and 1 %) were applied. The result showed that the soybean-corn starch interaction produced a strong network, decreasing the cooking loss. The addition of corn starch also improved the lightness and whiteness of analog rice. The formulation of 60 % soybean and 40 % corn starch produced analog rice with a balanced macronutrient composition, providing moderate levels of protein, fat, and carbohydrates, a relatively higher ash content, and the most compact and smoothest microstructure. Furthermore, the addition of TGase increased the texture profile of analog rice, reduced water absorption and volume expansion, and significantly prevented cooking losses. Hence, the combination of soybean flour and corn starch, along with the addition of TGase, improved the physicochemical properties, including the high protein content, color, texture, and cooking quality of analog rice.

Restructuring meat products is one way of improving material utilization and economic efficiency. In this process of combining meat pieces or granules to form larger pieces of meat, the additives and processing techniques employed in bonding the restructured meat play crucial roles in the formation of the structure and appearance of the meat while simultaneously reducing nutrient and water loss and enhancing flavor. This study reviews the adhesives commonly used in meat recombination technology, including transglutaminase, glucono-delta-lactone, fibrin, gelatin, and gel emulsifiers such as hydrophilic colloid, phosphate, starch, and cellulose. Additionally, processing technologies such as high-pressure, ultrasonic, vacuum-assisted, microwave, and three-dimensional printing are discussed, with emphasis on their principles, properties, functionalities, and safety. The study further summarizes the application and research progress of various bonding techniques in restructured meat. It analyzes the advantages, challenges, and development prospects of these techniques to provide support for further research in this field.

Acid Protease and Transglutaminase enzymes were used to impart anti-felting properties to wool with minimal loss in tensile strength. Statistical optimisation of the application conditions using Box Behnken design of experiment was employed to achieve less than 3% total warp shrinkage as specified in Woolmark Specification AW-1 for machine washable care claim. During optimisation of protease treatment, the total warp shrinkage was reduced from 7.66% to 2.77% but was accompanied with 9.95% loss in warp tensile strength. Subsequently, optimisation of transglutaminase enzyme was carried out on protease treated wool. This resulted in marginal reduction of total warp shrinkage to 2.64% with 7.92% recovery in warp tensile strength giving a net loss of 2.82% in warp tensile strength. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: The present study aimed to investigate the impact of TGase cross‐linking on the flavour characteristics, particularly focusing on its ability to reduce bitterness in enzymatically digested Alaska Pollock framework (APF) hydrolysates using Protease A 'Amano' 2SD (A2SD) and Protease A 'Amano' 6SD (A6SD). Electronic tongue results showed that the umami was enhanced, accompanied by a reduction in both bitterness and bitter aftertaste. The contents of glutamic acid (Glu) and nucleotides (AMP, IMP and GMP) exhibited significant differences among all treatment groups (P < 0.05). There was a notable increase in the types and relative concentrations of alcohols, ketones, alkanes and aldehydes in the cross‐linked APF enzymatic hydrolysate. The Fourier transform infrared spectroscopy, ultraviolet spectrum and fluorescence spectrum analyses indicate that TGase cross‐linking leads to a reduction in the exposure of hydrophobic amino acid residues. The surface hydrophobicity of HA2SD‐C and HA6SD‐C exhibited a significantly lower level compared with that of HA2SD and HA6SD. The present study presents an effective approach for mitigating the bitter taste of aquatic hydrolysate, thereby positively contributing to the advancement and utilisation of this valuable resource. [ABSTRACT FROM AUTHOR]

Background: Gluten sensitivity (GS) is one of the gluten-related disorders (GRDs). Patients with GS may have serum antibodies against tissue transglutaminase (tTG) (IgA and IgG) without any evidence of enteropathy. We aimed to evaluate both tTG-6 and tTG-2 antibodies to determine the prevalence of seropositive tTG-2 and tTG-6 antibodies in patients with multiple sclerosis (MS). Methods: In this cross-sectional study, we carried out serological tests (IgA & IgG anti-tTG-6 and tTG-2 antibodies) in patients with MS. Results: Seventy-two patients with MS were included in this study. Of them, seropositive patients for total (IgA + IgG) of tTG-6 and tTG-2 autoantibodies were 9.7% (95% CI, 4.2-18) and 5.6% (95% CI, 1.4-12.5), respectively. Conclusion: Anti-tTG-6 antibody testing may be necessary for early diagnosis of GS in patients with MS. More studies with larger sample sizes are warranted to confirm these data. [ABSTRACT FROM AUTHOR]

The food enzyme protein–glutamine γ‐glutamyltransferase (protein–glutamine: amine γ‐glutamyltransferase; EC 2.3.2.13) is produced with the non‐genetically modified Streptomyces mobaraensis strain M2020197 by Taixing Dongsheng Bio‐Tech Co. Ltd. The identity of the production strain and the absence of viable cells could not be established. The food enzyme is intended to be used in eight food manufacturing processes: processing of cereals and other grains for the production of (1) baked products, (2) cereal‐based products other than baked; processing of dairy products for the production of (3) fermented dairy products, (4) cheese, (5) dairy desserts; processing of plant‐ and fungal‐derived products for the production of (6) meat analogues, (7) plant‐based analogues of milk and milk products; processing of meat and fish products for the production of (8) modified meat and fish products. Dietary exposure to the food enzyme–total organic solids (TOS) was estimated to be up to 3.498 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 91 mg TOS/kg bw per day. The calculated margin of exposure for each age group was 36 (infants), 26 (toddlers), 50 (children), 99 (adolescents), 115 (adults) and 133 (the elderly). A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that a risk of allergic reactions upon dietary exposure to this food enzyme cannot be excluded, but the likelihood is low. The safety of the food enzyme could not be established given the derived margins of exposure. Therefore, the Panel concluded that the food enzyme could not be considered safe under the intended conditions of use. [ABSTRACT FROM AUTHOR]

Wheat gluten protein (WGP) is a fine-quality plant-based protein resource. However, as its unparalleled reticulation structure, the processing properties of WGP are extremely poor, limiting its application. To overcome these drawbacks, the purpose of this work was to embellish wheat gluten protein by three relatively novel and mainstream chemical modifications. The results showed the pH-shifting treatment altered the apparent morphology of protein, showing a uniform flocculent structure, leading to significant improvements in foaming capacity and emulsification property. After deamidation by acetic acid, the solubility of WGP was greatly improved (60.1%), which was nearly four times that of the control group (15.8%), and its foam stability was also significantly improved. The WGP had the highest thermal stability (deformation temperature up to 148 ℃) after TGase deamidation. These results indicate that the three modification methods enhance the functional characters of WGP in different aspects and expand its application potential. [ABSTRACT FROM AUTHOR]

Abstract Pulmonary fibrosis is an interstitial scarring disease of the lung characterized by poor prognosis and limited treatment options. Tissue transglutaminase 2 (TG2) is believed to promote lung fibrosis by crosslinking extracellular matrix components and activating latent TGFβ. This study assessed physiologic pulmonary function and metabolic alterations in the mouse bleomycin model with TG2 genetic deletion. TG2‐deficient mice demonstrated attenuated the fibrosis and preservation of lung function, with significant reduction in elastance and increases in compliance and inspiratory capacity compared to control mice treated with bleomycin. Bleomycin induced metabolic changes in the mouse lung that were consistent with increased aerobic glycolysis, including increased expression of lactate dehydrogenase A and increased production of lactate, as well as increased glutamine, glutamate, and aspartate. TG2‐deficient mice treated with bleomycin exhibited similar metabolic changes but with reduced magnitude. Our results demonstrate that TG2 is required for a typical fibrosis response to injury. In the absence of TG2, the fibrotic response is biochemically similar to wild‐type, but lesions are smaller and lung function is preserved. We also show for the first time that profibrotic pathways of tissue stiffening and metabolic reprogramming are interconnected, and that metabolic disruptions in fibrosis go beyond glycolysis.

In recent years, vegetarian meat has seen significant growth in the market. However, vegetarian shrimp remains suboptimal, primarily because it is made from konjac, lacking the authentic texture of shrimp. This study aimed to enhance the texture of vegetarian shrimp by using various commercial plant proteins (soy, pea, Cyanobacteria, and wheat protein) combined with different transglutaminase (TGase) concentrations (0.1% and 0.5%). These were tested under specific temperatures (25 °C and 50 °C) and incubation periods (20 and 60 min) to establish a correlation between protein profiles and food texture. For comparison, three types of frozen shrimp (grass shrimp, prawn, and lobster) were used as benchmarks. The protein profiles and scanning electron microscope images of these frozen shrimps showed minor differences. The plant proteins profiles and textures were notably influenced by the varied TGase concentrations, temperatures, and incubation times. Moreover, when TGase was added, both soy and pea proteins achieved a texture akin to that of frozen lobster. Incorporating 0.5% TGase into soy and pea proteins resulted in vegetarian shrimp that closely resembled lobster in both protein profile and texture. Additionally, experimental data suggested that using Cyanobacteria and wheat proteins could enhance the flavor and springiness of the food. Overall, this study may serve as a valuable reference for the preparation of vegetarian shrimp.