About using transglutaminase enzyme in the food industry

В последние годы в Российской Федерации (РФ) появились сообщения об использовании в пищевой промышленности технологического вспомогательного средства (ТВС) - ферментного препарата на основе микробиальной трансглютаминазы (мТГ), который не входит в перечень разрешенных для использования в пищевой промышленности Евразийского экономического союза (ЕАЭС). Анализ данных показал, что используемые в настоящее время в пищевой промышленности штаммы-продуценты мТГ - Streptomyces mobaraensis DSM40587 и Streptomyces mobaraensis S-8112 - наряду с этим ферментом могут синтезировать антибиотики блеомицин, детоксин, пиерицидин А, а также ферменты антибиотикоустойчивости, такие как пенициллин ацилазу, бета-лактамазу, что служит развитию антибиотикоустойчивости у микроорганизмов. При поступлении в желудочно-кишечный тракт (ЖКТ) в составе пищевой продукции мТГ может вызывать изменение структуры белков слизистой оболочки кишечника. Под влиянием мТГ увеличивается проницаемость стенки кишечника, происходит активация иммунного ответа, увеличивается антигенная нагрузка иммунной системы, происходит нарушение связи ДНК с гистонами. Показано, что мТГ может явиться причиной увеличения частоты проявления симптомов целиакии у гипосимптомных с неустановленным диагнозом генетически восприимчивых лиц, нарушения адгезии белков при формировании синдрома Альцгеймера, аллергии, а также нарушений иммунного статуса организма и микробиоценоза кишечника. Данный фермент является привлекательным для производителей в связи с высокой эффективностью применения мТГ в технологическом процессе производства пищевой продукции из некачественного и некондиционного сырья, что обуславливает значимые экономические выгоды и возможность отказа от использования пищевых добавок. Последнее позволяет формировать у потребителя представление о высоком качестве вырабатываемой пищевой продукции. В связи с установленными рисками здоровью населения при использовании мТГ, отсутствием разрешения на ее использование в пищевой промышленности ЕАЭС, возможностью применения этого фермента в целях введения в заблуждение потребителей считаем необходимым проведение дополнительных оценок рисков здоровью и введение обязательного мониторинга на наличие остаточной активности этого фермента в пищевой продукции. In recent years, in the Russian Federation (RF), there have been reports about use in the food industry of processing aid (PA) - an enzyme preparation based on microbial transglutaminase (mTG), which is not included in the list of permitted for use in the food industry of the Eurasian Economic Union (EAEU). Analysis of the data showed that the currently used in the food industry strains-producer of mTG - Streptomyces mobaraensis DSM40587 and Streptomyces mobaraensis S-8112, along with this enzyme, have been synthesizing antibiotics bleomycin, detoxin, piericidin A, as well as such enzymes - penicillin acylases, beta-lactamazes, which could be reasons of antibioticoresistance of microorganisms. mTG when introduced into the gastrointestinal tract as part of food, could change the structure of proteins in the intestinal mucosa. Under the influence of mTG have increased intestinal permeability, immune system antigenic load, have been promoted the immune response, have been intensifying connection between DNA and histones. It has been shown that mTG could cause an increase the frequency of detection of celiac disease in hyposymptomatic / with an undetermined diagnosis of genetically susceptible individuals, impaired protein adhesion during the formation of Alzheimer's syndrome, allergies, as well as impaired of immune status and gut's microbiosis. This enzyme is attractive to manufacturers due to the high efficiency of the use of mTG in the technological process of food production from low-quality and substandard raw materials, which leads to significant economic benefits and the possibility of abandoning the use of food additives. The latter fact allows the consumer to form an idea of the high quality of the produced food. In connection with the established risks mTG for public health, lack of permission for its use in the food industry of the EAEU and the possibility of using this enzyme in order to mislead consumers, we consider it necessary to carry out additional health risk assessments and introduce mandatory monitoring for the presence of residual activity of this enzyme in food.

Atomic Force Microscopy Characterization of Biomaterials Modified with Poly(styrene Sulfonate)

<p>Polycaprolactone and polyethylene terephthalate are widely used to elaborate biomaterials and medical devices in particular for long-term implant applications but tuning their surface properties remains challenging. We investigate surface functionalization by grafting poly(sodium 4-styrene sulfonate) with the aim of enhancing protein adhesion and cellular activity. Elucidating the topography and molecular level organization of the modified surfaces is important for understanding and predicting biological activity. In this work, we explore several grafting methods including thermal grafting, thermal grafting in the presence of Mohr's salt, and UV activation. We characterize the different surfaces obtained using atomic force microscopy, contact angle and X-ray photoelectron spectroscopy. The results reveal striking differences in the properties of the modified surfaces. This work demonstrates tuning of biomaterials surface by functionalization and the capability of atomic force microscopy to provide insights into the conformation and mechanical properties of the grafted polymers. </p>

Atomic Force Microscopy Characterization of Biomaterials Modified with Poly(styrene Sulfonate)

<p>Polycaprolactone and polyethylene terephthalate are widely used to elaborate biomaterials and medical devices in particular for long-term implant applications but tuning their surface properties remains challenging. We investigate surface functionalization by grafting poly(sodium 4-styrene sulfonate) with the aim of enhancing protein adhesion and cellular activity. Elucidating the topography and molecular level organization of the modified surfaces is important for understanding and predicting biological activity. In this work, we explore several grafting methods including thermal grafting, thermal grafting in the presence of Mohr's salt, and UV activation. We characterize the different surfaces obtained using atomic force microscopy, contact angle and X-ray photoelectron spectroscopy. The results reveal striking differences in the properties of the modified surfaces. This work demonstrates tuning of biomaterials surface by functionalization and the capability of atomic force microscopy to provide insights into the conformation and mechanical properties of the grafted polymers. </p>

Biocompatible chicken bone extracted dahllite/hydroxyapatite/collagen filler based polysulfone membrane for dialysis

In the current study, dahllite/hydroxyapatite/collagen filler extracted via calcination of wasted chicken bone was blended with PSf polymer to obtain highly biocompatible, and antifoulant hemodialysis membranes. FTIR and Raman spectroscopic analysis was done to obtain information about the bonding chemistry of the obtained filler. The intermolecular interaction that existed between dahllite/hydroxyapatite/collagen filler and pristine PSf was confirmed by Raman spectroscopic study. The PSf polymer exhibited a sponge-like structure owing to its high thickness and slow exchange with non-solvent in coagulation bath whilst the instantaneous de-mixing course produced finger-like capillaries in dahllite/hydroxyapatite/collagen filler based PSf membranes as exposed by SEM photographs. The presence of different wt. % of filler composition in the PSf matrix improved the mechanical strength as revealed by fatigue analysis. The hydrophilic character improved by 78% while leaching consistency adjusted to 0%–4%. Pure water permeation (PWP) flux improved by nine times. The pore profile improved with the addition of filler as revealed by hydrophilicity experiment, PWP flux, and SEM micrographs. Fouling evaluation results disclosed that filler based membranes showed 36% less adsorption of protein (BSA) solution together with more than 84% flux recovery ratio. The biocompatibility valuation analysis unveiled that membranes composed of filler showed extended prothrombin and thrombin coagulation times, reduced activation of fibrinogen mass, and less adhesion of plasma proteins in comparison with pristine PSf membrane. The adsorption capacity of fabricated membranes for urea and creatinine improved by 31% (in the case of urea) and 34% (in the case of creatinine) in contrast with pristine PSf membrane. The overall results showed that the M-3 membrane was optimized in terms of surface properties, protein adhesion, anticoagulation activity, and adsorption amount of urea and creatinine.

An antifouling polymer for dynamic anti-protein adhesion analysis by quartz crystal microbalance

Nowadays, the non-specific adsorption of biomolecules is a key issue in many fields. Herein, an improved antifouling molecule was synthetised by grafting phenol with oligopoly (ethylene glycol), named (4-(2-(2-ethoxyethoxy) ethoxy)...

Bio-Interactive Zwitterionic Dental Biomaterials for Improving Biofilm Resistance: Characteristics and Applications

Biofilms are formed on surfaces inside the oral cavity covered by the acquired pellicle and develop into a complex, dynamic, microbial environment. Oral biofilm is a causative factor of dental and periodontal diseases. Accordingly, novel materials that can resist biofilm formation have attracted significant attention. Zwitterionic polymers (ZPs) have unique features that resist protein adhesion and prevent biofilm formation while maintaining biocompatibility. Recent literature has reflected a rapid increase in the application of ZPs as coatings and additives with promising outcomes. In this review, we briefly introduce ZPs and their mechanism of antifouling action, properties of human oral biofilms, and present trends in anti-biofouling, zwitterionic, dental materials. Furthermore, we highlight the existing challenges in the standardization of biofilm research and the future of antifouling, zwitterated, dental materials.

Surface properties of chitosan/montmorillonite films for biomedical applications

In this study, we firstly investigated the surface and protein adsorption properties of montmorillonite (MMT)/chitosan (CS) composite films with various MMT/CS weight ratios for metallic implants coating applications. Bicinchoninic acid (BCA) protein assay results show that the neat CS film exhibits a high concentration of bovine serum albumin (BSA) protein adhesion because the abundant carbonyl and amide functional groups on the surface of the CS film easily form hydrogen bonds with the copious carboxylic acid groups on the surface of the BSA protein. The MMT/CS composite films with MMT/CS = 3, 5, 8, and 10 possess a much lower BSA adhesion concentration than that of the neat CS film, as some of the carbonyl and amide functional groups on the surface of the composite films are replaced by the –Si–O–Si and –Al–O–Al groups. Among these MMT/CS composite films, the film with MMT/CS = 5 exhibits the lowest BSA adsorption concentration because it possesses a higher MMT content than those with MMT/CS = 1 and 3 and a smoother and non-porous surface than those with MMT/CS = 8 and 10. According to our results, MMT/CS composite films with appropriate MMT/CS weight ratios exhibit better surface and protein adsorption properties than neat CS for biomedical applications.

Improvement in the Microbial Resistance of Resin-Based Dental Sealant by Sulfobetaine Methacrylate Incorporation

Prevention of dental caries is a key research area, and improvement of the pit and fissure sealants used for caries prevention has been of particular interest. This report describes results of incorporating a zwitterion, sulfobetaine methacrylate (SB), into photo-polymerized resin-based sealants to enhance resistance to cariogenic bacteria and protein adhesion. Varying amounts (1.5–5 wt%) of SB were incorporated into a resin-based sealant, and the flexural strength, wettability, depth of cure, protein adhesion, bacterial viability, and cell cytotoxicity of the resultant sealants were evaluated. The flexural strength decreased with the increasing SB content, but this decrease was statistically significant only for sealants containing ≥3 wt% SB. Incorporating a zwitterion led to a significant reduction in the water contact angle and protein adhesion. The colony-forming unit count showed a significant reduction in the bacterial viability of S. mutans, which was confirmed with microscopic imaging. Moreover, cell cytotoxicity analysis of SB-modified sealants using an L929 fibroblast showed a cytotoxicity comparable to that of an unmodified control, suggesting no adverse effects on the cellular metabolism upon SB introduction. Hence, we conclude that the addition of 1.5–3 wt% SB can significantly enhance the inherent ability of sealants to resist S. mutans adhesion and prevent dental caries.