Selection of lactic acid bacteria strains for the hydrolysis of allergenic proteins of wheat flour

Screening of probiotic Lactobacillus to reduce peanut allergy and with potential anti-allergic activity

BACKGROUND

Peanut is a significant source of nutrition and a valuable oilseed crop. It is also a serious allergy source, which poses a threat to 1.1% of the population. This study aimed to screen lactic acid bacteria (LAB) with the capacity to alleviate peanut allergenicity and exhibit anti-allergic properties.

RESULT

The results show that LAB can make use of substances in peanuts to reduce the pH of peanut milk from 6.603 to 3.593-4.500 by acid production and that it can utilize the protein in peanuts to reduce the allergenic content (especially Ara h 1) and improve biological activity in peanut pulp. The content of Ara h 1 peanut-sensitizing protein was reduced by 74.65% after fermentation. The protein extracted from fermented peanut pulp is more readily digestible by gastrointestinal juices. The inhibitory activity assay of hyaluronidase (an enzyme with strong correlation to allergy) increased from 46.65% to a maximum of 90.57% to reveal that LAB fermentation of peanut pulp exhibited a robust anti-allergic response.

CONCLUSION

The strains identified in this study exhibited the ability to mitigate peanut allergenicity partially and to possess potential anti-allergic properties. Lactobacillus plantarum P1 and Lactobacillus salivarius C24 were identified as the most promising strains and were selected for further research. © 2023 Society of Chemical Industry.

Tackling food allergens-The role of food processing on proteins' allergenicity

This chapter examines how innovative and emerging food processing technologies, such as those that use heat, electricity, electromagnetic waves, and pressure, can modify protein denaturation, aggregation, and intermolecular interactions pathways, which can result in varying immunoreactive responses. It emphasizes the need to understand how these processing methods affect the protein epitopes recognized by antibodies and their respective priming pathways, especially during the sensitization stage that precedes an allergic response. Although traditional processing methods have been investigated, the impact of novel technologies on food protein allergenicity remains largely unknown. The chapter specifically focuses on milk proteins, which have clinical significance and are associated with cow's milk allergy, one of the most common food allergies in young children. Additionally, it examines potential scientific advancements that novel processing methods may bring to this field.

Probiotics in the Sourdough Bread Fermentation: Current Status

Sourdough fermentation is an ancient technique to ferment cereal flour that improves bread quality, bringing nutritional and health benefits. The fermented dough has a complex microbiome composed mainly of lactic acid bacteria and yeasts. During fermentation, the production of metabolites and chemical reactions occur, giving the product unique characteristics and a high sensory quality. Mastery of fermentation allows adjustment of gluten levels, delaying starch digestibility, and increasing the bio-accessibility of vitamins and minerals. This review focuses on the main steps of sourdough fermentation, the microorganisms involved, and advances in bread production with functional properties. The impact of probiotics on human health, the metabolites produced, and the main microbial enzymes used in the bakery industry are also discussed.

Toward Sourdough Microbiome Data: A Review of Science and Patents

Technological prospecting was performed on documents related to sourdough microbiota using SCOPUS, Web of Science, Google Scholar, Espacenet and Patent Inspiration databases. Scientific articles and patents were analyzed based on three different perspectives: macro (year of publication, country, and institutions), meso (categorization as different taxonomies according to the subject evaluated), and micro (in-depth analysis of the main taxonomies, gathering the documents in subcategories). The main subject addressed in patents was the starter and product preparation, while 58.8% of the scientific publications focused on sourdough starter microbiota (identification and selection of microorganisms). Most patents were granted to companies (45.9%), followed by independent inventors (26.4%) and universities (21.8%). Sourdough products are in the spotlight when the subject is the bakery market; however, a closer integration between academia and industry is needed. Such a collaboration could generate a positive impact on the sourdough market in terms of innovation, providing a bread with a better nutritional and sensory quality for all consumers. Moreover, sourdough creates a new magnitude of flavor and texture in gastronomy, providing new functional products or increasing the quality of traditional ones.

The Ability of the Yeast Wickerhamomyces anomalus to Hydrolyze Immunogenic Wheat Gliadin Proteins

Gliadins proteins make up around 30% of total wheat flour proteins. They are involved in many immune disorders affecting an increasing number of people who eat foods made with wheat flour. The triggering factor is the accumulation in the gut of immunogenic peptides derived from incomplete degradation of gliadins by gastric proteases. Previous research has revealed the effectiveness of sourdough-fermentation technology or related lactic acid bacteria in reducing wheat flour allergenic proteins. However, there are no single yeast cultures for producing reduced allergenicity wheat products. This study evaluated sourdough-related yeast Wickerhamomyces anomalus strains for their ability to hydrolyze gliadin proteins. All yeast strains were able to degrade gliadins and use them as carbon and nitrogen sources. The proliferation of the yeast strains depended on the gliadin addition; complete hydrolysis was observed after 24 h. The strain showing higher proteolytic activity fermented, acceptably wheat flour dough. The gliadin content of the leavened dough was reduced by 50%. Bread made from the W. anomalus-fermented dough showed a 78% reduction in immunogenic α-gliadins. 50% of the decrease was attributed to the proteolytic activity of the yeast cells, and the other 35% to the baking process. These results show the potential of the yeast W. anomalus as a starter for reducing immunogenicity wheat products.

Fermentation weight loss, fermentation quality, and bacterial community of ensiling of sweet sorghum with lactic acid bacteria at different silo densities

Sweet sorghum is an important forage in arid and semi-arid climatic regions. This study aimed to reveal the fermentation weight loss (FWL), fermentation quality, and bacterial community of ensiling of sweet sorghum with lactic acid bacteria LAB; (Lactiplantibacillus plantarum and Lentilactobacillus buchneri) at different silo densities. For this study, sweet sorghum was harvested at the first spikelet of inflorescence stage and ensiled without or with LAB (CK or L) in polyethylene laboratory-scale silos (diameter, 20 cm; height, 30 cm) at densities of 650 (CK_650 and L_650), 700 (CK_700 and L_700), and 750 kg/m3 (CK_750 and L_750), respectively. The FWL, fermentation quality, microbial counts, and bacterial community of the silage were assessed after 100 days of ensiling. L_750 had a lower FWL than CK_650, _700, and _750 after 100 days of ensiling (P < 0.005), and the FWL was affected by silo density and inoculating LAB (P < 0.005). All silages had low pH (<4.0) and ammonia nitrogen content (<50 g/kg total nitrogen) and did not contain propionic and butyric acids; moreover, inoculating LAB increased lactic and acetic acids (P < 0.005). Bacterial communities in inoculated and uninoculated silages were clustered together, respectively, and clearly separated from each other. The total abundance of Lactiplantibacillus and Lentilactobacillus in fresh forage was <1%. Lactiplantibacillus had the highest abundance in all silages (from 71.39 to 93.27%), followed by Lentilactobacillus (from 3.59 to 27.63%). Inoculating LAB increased the abundance of Lentilactobacillus in each silo density (P < 0.005) and decreased Lactiplantibacillus in the silage in densities of 700 and 750 kg/m3 (P < 0.005); moreover, increasing silo density decreased Lactiplantibacillus abundance and increased Lentilactobacillus abundance in inoculated silages (P < 0.005). Overall, sweet sorghum silage showed satisfactory fermentation quality, with a density of no <650 kg/m3, and inoculating LAB improved fermentation quality and reduced FWL. Lactiplantibacillus and Lentilactobacillus presented as minor taxa in fresh sweet sorghum and dominated the bacterial community of all silages. Inoculating LAB was the main factor affecting the bacterial community of sweet sorghum silage. Moreover, inoculating LAB and increasing silo density can contribute to the decreasing Lactiplantibacillus abundance and increasing Lentilactobacillus abundance.

Effective Degradation of Gluten and Its Fragments by Gluten-Specific Peptidases: A Review on Application for the Treatment of Patients with Gluten Sensitivity

To date, there is no effective treatment for celiac disease (CD, gluten enteropathy), an autoimmune disease caused by gluten-containing food. Celiac patients are supported by a strict gluten-free diet (GFD). However, in some cases GFD does not negate gluten-induced symptoms. Many patients with CD, despite following such a diet, retain symptoms of active disease due to high sensitivity even to traces of gluten. In addition, strict adherence to GFD reduces the quality of life of patients, as often it is difficult to maintain in a professional or social environment. Various pharmacological treatments are being developed to complement GFD. One promising treatment is enzyme therapy, involving the intake of peptidases with food to digest immunogenic gluten peptides that are resistant to hydrolysis due to a high prevalence of proline and glutamine amino acids. This narrative review considers the features of the main proline/glutamine-rich proteins of cereals and the conditions that cause the symptoms of CD. In addition, we evaluate information about peptidases from various sources that can effectively break down these proteins and their immunogenic peptides, and analyze data on their activity and preliminary clinical trials. Thus far, the data suggest that enzyme therapy alone is not sufficient for the treatment of CD but can be used as a pharmacological supplement to GFD.

Creating hypo-/nonallergenic wheat products using processing methods: Fact or fiction?

Wheat allergy is a potentiallylife-threatening disease that affects millions of people around the world. Food processing has been shown to influence the allergenicity of wheat and other major foods. However, a comprehensive review evaluating whether or not food processing can be used to develop hypo-/nonallergenic wheat products is unavailable. There were three objectives for this study: (1) to critically evaluate the evidence on the effect of fermentation, thermal processing, and enzyme or acid hydrolysis on wheat allergenicity so as to identify the potential for and challenges of using these methods to produce hypo-/nonallergenic wheat products; (2) to identify the molecular effects of food processing needed to create such products; and (3) to map the concept questions for future research and development to produce hypo-/nonallergenic wheat products. We performed literature research using PubMed and Google Scholar databases with various combinations of keywords to generate the data to accomplish these objectives. We found that: (1) food processing significantly modulates wheat allergenicity; while some methods can reduce or even abolish the allergenicity, others can create mega allergens; and (2) fermentation and enzymatic hydrolysis hold the most potential to create novel hypo-/nonallergenic wheat products; however, preclinical validation and human clinical trials are currently lacking. We also identify five specific research concepts to advance the research to enable the creation of hypo-/nonallergenic wheat products for application in food, medical, and cosmetic industries.

Fermentation of Gluten by Lactococcus lactis LLGKC18 Reduces its Antigenicity and Allergenicity

Wheat is a worldwide staple food, yet some people suffer from strong immunological reactions after ingesting wheat-based products. Lactic acid bacteria (LAB) constitute a promising approach to reduce wheat allergenicity because of their proteolytic system. In this study, 172 LAB strains were screened for their proteolytic activity on gluten proteins and α-amylase inhibitors (ATIs) by SDS-PAGE and RP-HPLC. Gliadins, glutenins, and ATI antigenicity and allergenicity were assessed by Western blot/Dot blot and by degranulation assay using RBL-SX38 cells. The screening resulted in selecting 9 high gluten proteolytic strains belonging to two species: Enterococcus faecalis and Lactococcus lactis. Proteomic analysis showed that one of selected strains, Lc. lactis LLGKC18, caused degradation of the main gluten allergenic proteins. A significant decrease of the gliadins, glutenins, and ATI antigenicity was observed after fermentation of gluten by Lc. lactis LLGKC18, regardless the antibody used in the tests. Also, the allergenicity as measured by the RBL-SX38 cell degranulation test was significantly reduced. These results indicate that Lc. lactis LLGKC18 gluten fermentation can be deeply explored for its capability to hydrolyze the epitopes responsible for wheat allergy.

Metabolism Characteristics of Lactic Acid Bacteria and the Expanding Applications in Food Industry

Lactic acid bacteria are a kind of microorganisms that can ferment carbohydrates to produce lactic acid, and are currently widely used in the fermented food industry. In recent years, with the excellent role of lactic acid bacteria in the food industry and probiotic functions, their microbial metabolic characteristics have also attracted more attention. Lactic acid bacteria can decompose macromolecular substances in food, including degradation of indigestible polysaccharides and transformation of undesirable flavor substances. Meanwhile, they can also produce a variety of products including short-chain fatty acids, amines, bacteriocins, vitamins and exopolysaccharides during metabolism. Based on the above-mentioned metabolic characteristics, lactic acid bacteria have shown a variety of expanded applications in the food industry. On the one hand, they are used to improve the flavor of fermented foods, increase the nutrition of foods, reduce harmful substances, increase shelf life, and so on. On the other hand, they can be used as probiotics to promote health in the body. This article reviews and prospects the important metabolites in the expanded application of lactic acid bacteria from the perspective of bioengineering and biotechnology.

Recent advances in alleviating food allergenicity through fermentation

The increasing prevalence of food allergies is a significant challenge to global food health and safety. Various strategies have been deployed to decrease the allergenicity of food for preventing and reducing related disorders. Compared to other methods, fermentation has unique advantages in reducing the allergenicity of food and may represent a new trend in preventing food-induced allergies. This review introduces the characteristics of allergens in various foods, including shellfish, soy, peanut, milk, tree nut, egg, wheat, and fish. The mechanism and pathological symptoms of allergic reactions are then summarized. Furthermore, the advantages of fermentation for reducing the allergenicity of these foods and preventing allergies are evaluated. Fermentation is an efficient approach for reducing or eliminating food allergenicity. Simultaneously, it improved the nutritional value and physicochemical properties of food materials. It is conceivable that a combination of mixed strain fermentation with additional processing, such as heat treatment, pulsed light, and ultrasonication, will efficiently reduce the allergenicity of various foods and preserve their unique taste and nutritional components, providing significance for patients with allergies.

Co-culture fermentation of Pediococcus acidilactici XZ31 and yeast for enhanced degradation of wheat allergens

Previous researchers have shown the potential of sourdough and isolated lactic acid bacteria in reducing wheat allergens. As the interactions of lactic acid bacteria with yeast is a key event in sourdough fermentation, we wished to investigate how yeast affects metabolism of lactic acid bacteria, thereby affecting protein degradation and antigenic response. In this study, three strains isolated from sourdough were selected for dough fermentation, namely Pediococcus acidilactici XZ31, Saccharomyces cerevisiae JM1 and Torulaspora delbrueckii JM4. The changes in dough protein during the fermentation process were studied. Protein degradation and antigenic response in dough inoculated with Pediococcus acidilactici XZ31 monoculture and co-culture with yeast were mainly evaluated by SDS-PAGE, immunoblotting, ELISA and Liquid chromatography-tandem mass spectrometry assay. The whole-genome transcriptomic changes in Pediococcus acidilactici XZ31 were also investigated by RNA sequencing. The results showed that water/salt soluble protein and Tri a 28/19 allergens content significantly decreased after 24 h fermentation. Co-culture fermentation accelerated the degradation of protein, and reduced the allergen content to a greater extent. RNA-sequencing analysis further demonstrated that the presence of yeast could promote protein metabolism in Pediococcus acidilactici XZ31 for a certain period of time. These results revealed a synergistic effect between Pediococcus acidilactici XZ31 and yeast degrading wheat allergens, and suggested the potential use of the multi-strain leavening agent for producing hypoallergenic wheat products.

Allergenicity of Fermented Foods: Emphasis on Seeds Protein-Based Products

Food allergy is an IgE-mediated abnormal response to otherwise harmless food proteins, affecting between 5% and 10% of the world preschool children population and 1% to 5% adults. Several physical, chemical, and biotechnological approaches have been used to reduce the allergenicity of food allergens. Fermentation processes that contribute to technological and desirable changes in taste, flavor, digestibility, and texture of food products constitute one of these approaches. Lactic acid bacteria (LAB), used as starter cultures in dairy products, are a subject of increasing interest in fermentation of plant proteins. However, the studies designed to assess the impact of LAB on reduction of allergenicity of seed proteins are at an early stage. This review presents the current knowledge on food fermentation, with a focus on seed proteins that are increasingly used as ingredients, and its impacts on food potential allergenicity.

Biliaderis C. Fermented Cereal-based Products: Nutritional Aspects, Possible Impact on Gut Microbiota and Health Implications

Fermentation, as a process to increase the security of food supply, represents an integral part of food culture development worldwide. Nowadays, in the evolving functional food era where new sophisticated technological tools are leading to significant transformations in the field of nutritional sciences and science-driven approaches for new product design, fermentation technology is brought to the forefront again since it provides a solid foundation for the development of safe food products with unique nutritional and functional attributes. Therefore, the objective of the present review is to summarize the most recent advances in the field of fermentation processes related to cereal-based products. More specifically, this paper addresses issues that are relevant to nutritional and health aspects, including their interrelation with intestinal (gut) microbiome diversity and function, although clinical trials and/or in vitro studies testing for cereal-based fermented products are still scarce.

Advances in Molecular Mechanisms of Wheat Allergenicity in Animal Models: A Comprehensive Review

The prevalence of wheat allergy has reached significant levels in many countries. Therefore, wheat is a major global food safety and public health issue. Animal models serve as critical tools to advance the understanding of the mechanisms of wheat allergenicity to develop preventive and control methods. A comprehensive review on the molecular mechanisms of wheat allergenicity using animal models is unavailable at present. There were two major objectives of this study: To identify the lessons that animal models have taught us regarding the molecular mechanisms of wheat allergenicity and to identify the strengths, challenges, and future prospects of animal models in basic and applied wheat allergy research. Using the PubMed and Google Scholar databases, we retrieved and critically analyzed the relevant articles and excluded celiac disease and non-celiac gluten sensitivity. Our analysis shows that animal models can provide insight into the IgE epitope structure of wheat allergens, effects of detergents and other chemicals on wheat allergenicity, and the role of genetics, microbiome, and food processing in wheat allergy. Although animal models have inherent limitations, they are critical to advance knowledge on the molecular mechanisms of wheat allergenicity. They can also serve as highly useful pre-clinical testing tools to develop safer genetically modified wheat, hypoallergenic wheat products, novel pharmaceuticals, and vaccines.

Identification and Antithrombotic Activity of Peptides from Blue Mussel (Mytilus edulis) Protein

The blue mussel (Mytilus edulis) reportedly contains many bioactive components of nutritional value. Water-, salt- and acid-soluble M. edulis protein fractions were obtained and the proteins were trypsinized. The resultant peptides were analyzed by ultra-performance liquid chromatography quadrupole time of flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS). 387 unique peptides were identified that matched 81 precursor proteins. Molecular mass distributions of the proteins and peptides were analyzed by sodium dodecyl sulfate-polyacryl amide gel electrophoresis (SDS-PAGE). The differences between the three protein samples were studied by Venn diagram of peptide and protein compositions. Toxicity, allergic and antithrombotic activity of peptides was predicted using database website and molecular docking respectively. The antithrombotic activity of enzymatic hydrolysate from water-, salt- and acid-soluble M. edulis protein were 40.17%, 85.74%, 82.00% at 5 mg/mL, respectively. Active mechanism of antithrombotic peptide (ELEDSLDSER) was also research about amino acid binding sites and interaction, simultaneously.