Phytase producing lactic acid bacteria: Cell factories for enhancing micronutrient bioavailability of phytate rich foods

Unveiling the nutritional composition and bioactivity of Ethiopian native fermented foods: Kocho and Injera

Kocho and Injera are traditional Ethiopian foods but there is scarce information about their composition and potential health benefits. The aim of this research was to elucidate the nutritional and bioactivbe profiles of Kocho and Injera (white and brown) breads, and assessed the impact of in vitro digestion on their constituents. Kocho bread was rich in fiber (11.3 g/100 g dw), riboflavin (54.7 μg/100 g dw), and γ-aminobutyric acid (GABA, 36 mg/100 g dw). White and brown Injera had a notable content of protein (7.6-8.5 g/100 g dw), fiber (∼14 g/100 g dw), riboflavin (85.4-100.0 μg/100 g dw), polyols, sugars and oligosaccharides (123.0-261.3 mg/100 g dw), free amino acids (FAA,∼200 mg/100 g dw), GABA (46.0-55.5 mg/100 g dw), free phenolic compounds (FPC, 468.1-615.7 mg GAE/100 g dw), and antioxidant activity (399.2-888.3 mg TE/100 g dw). In vitro digestion increased FAA, peptides, GABA and FPC in the samples and two bioactive peptides were identified per sample.

Metabolic insights of lactic acid bacteria in reducing off-flavors and antinutrients in plant-based fermented dairy alternatives

Multiple sensorial, technological, and nutritional challenges must be overcome when developing plant-based fermented dairy alternatives (PBFDA) to mimic their dairy counterparts. The elimination of plant-derived off-flavors (green, earthy, bitter, astringent) and the degradation of antinutrients are crucial quality factors highlighted by the industry for their effect on consumer acceptance. The adaptation of plant-derived lactic acid bacteria (LAB) species into plant niches is relevant when developing starter cultures for PBFDA products due to their evolutionary acquired ability to degrade plant-based undesirable compounds (off-flavors and antinutrients). Some plant-isolated species, such as Lactiplantibacillus plantarum and Limosilactobacillus fermentum, have been associated with the degradation of phytates, phenolic compounds, oxalates, and raffinose-family oligosaccharides (RFOs), whereas some animal-isolated species, such as Lactobacillus acidophilus strains, can metabolize phytates, RFOs, saponins, phenolic compounds, and oxalates. Some proteolytic LAB strains, such as Lacticaseibacillus paracasei and Lacticaseibacillus rhamnosus, have been characterized to degrade phytates, protease inhibitors, and oxalates. Other species have also been described regarding their abilities to biotransform phytic acid, RFOs, saponins, phenolic compounds, protease inhibitors, oxalates, and volatile off-flavor compounds (hexanal, nonanal, pentanal, and benzaldehyde). In addition, we performed a blast analysis considering antinutrient metabolic genes (42 genes) to up to 5 strains of all qualified presumption of safety-listed LAB species (55 species, 240 strains), finding out potential genotypical capabilities of LAB species that have not conventionally been used as starter cultures such as Lactiplantibacillus pentosus, Lactiplantibacillus paraplantarum, and Lactobacillus diolivorans for plant-based fermentations. This review provides a detailed understanding of genes and enzymes from LAB that target specific compounds in plant-based materials for plant-based fermented food applications.

Lactic acid fermentation improves nutritional and functional properties of chickpea flours

Consumption of healthy diets with low environmental impact is crucial for improving global health. Legumes, like chickpeas, serve as valuable meat alternatives due to their nutritional profile, which may be improved through fermentation. This study aimed to develop innovative fermented chickpea flours using lactic acid bacteria (LAB) strains from diverse ecosystems and evaluate their nutritional and functional properties in vitro. Fourteen batches of 20% chickpea-based puree were produced and fermented with 14 LAB isolated from different ecosystems. After fermentation, flours were obtained by freeze-drying. Most LAB grew well and reduced the pH of chickpea purees below 5 within 48 h. The flours were characterized for the content of polyphenols, bioactive peptides (BAPs), free amino groups (FAG), and phytic acid along with the total antioxidant capacity (TAC). Results showed that flours fermented by four LAB strains, including Enterococcus hirae and Enterococcus faecium had higher FAG and BAPs, including inhibitors of Dipeptidyl peptidase-IV and Angiotensin-converting enzyme. Flours fermented by Leuconostoc mesenteroides OM94, Lactiplantibacillus plantarum 299v, Lactiplantibacillus plantarum E75, Lactiplantibacillus plantarum LPPB, and Lacticaseibacillus casei LBC491 contained higher amounts of polyphenols, had soluble TAC that was 10-fold and direct TAC 3-fold higher, and lower phytic acid content than the control flour. Pyrogallol was detected in fermented products for the first time, and protocatechuic 4-O-glucoside increased three times in chickpea flours fermented by Leuconostoc mesenteroides OM94 compared to the control. In conclusion, fermentation improved the nutritional and functional qualities of chickpea flour, identifying promising LAB strains to enhance antioxidant capacity and polyphenols availability.

Quinoa snack elaborated with Lactiplantibacillus plantarum CRL 1964 sourdough increases the mineral bioavailability in mice

BACKGROUND

Consumption of pseudocereal-based foods decreased in phytate concentration can provide better nutrition concerning mineral bioavailability. This study aimed to evaluate the mineral bioavailability of quinoa sourdough-based snacks in a murine model. The mice were divided into five groups. One group was fed with basal snacks; three control groups received quinoa-based snacks made from non-fermented dough, dough without inoculum, and chemically acidified dough; and the test group (GF) received quinoa snacks elaborated from sourdough fermented by a phytase-positive strain, Lactiplantibacillus plantarum CRL 1964. Food intake, body weight, and mineral concentration in blood and organs (liver, kidney, and femur) were determined.

RESULTS

Food consumption increased during the feeding period and had the highest (16.2-24.5%) consumption in the GF group. Body weight also increased during the 6-weeks of trial. The GF group showed higher (6.0-10.2%) body weight compared with the other groups from the fifth week. The concentrations of iron, zinc, calcium, magnesium, and phosphorus in blood, iron and phosphorus in the liver, manganese and magnesium in the kidney, and calcium and phosphorus in the femur increased significantly (1.1-2.7-fold) in the GF group compared to the control groups.

CONCLUSION

The diet that includes quinoa snacks elaborated with sourdough fermented by phytase-positive strain L. plantarum CRL 1964 increased the concentrations of minerals in the blood, liver, kidney, and femur of mice, counteracting the antinutritional effects of phytate. This study demonstrates that the diminution in phytate content and the consequent biofortification in minerals are a suitable tool for producing novel foods. © 2024 Society of Chemical Industry.

Pre-exposure of Lactobacillus acidophilus to stress conditions impacts the metabolites and bioaccessibility of calcium and carotenoids in fermented dairy products

This study evaluated the impact of fermentation with Lactobacillus acidophilus pre-subjected to acid, osmotic, and oxidative stress conditions on the production of metabolites and the bioaccessibility of nutrients and bioactive compounds in fermented milks and yogurts. The products were added with orange bagasse (additional calcium - Ca source) and buriti pulp (carotenoids source). Gas chromatography coupled with mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) were used to analyze the volatile and non-volatile compounds metabolites from fermentation, respectively. In vitro digestion assays (dialysis and micellization) evaluated the bioaccessibility of Ca and carotenoids. Results showed that fermentation with L. acidophilus, previously exposed to acid, osmotic, and oxidative stress conditions, increased the production of volatiles such as higher alcohols and compounds derived from amino acid catabolism (1-butanol, 1-decanol, 1-nonanol, nonanoic acid, 2-ethyl 1-hexanol, 1-methoxy-2-propanol). Also, when this microorganism was subjected to osmotic and oxidative stress, an increase in the bioaccessibility of Ca in natural fermented milks from 4.1 % to 13.3-15.5 % and in the same products fortified with orange bagasse from 5.3 % to 9.3-10.8 % (when compared to the non-stressed condition) were observed. Conversely, the use of L. acidophilus - non-stressed or subjected to oxidative stress - reduced the bioaccessibility of carotenoids in products containing buriti pulp from 9.6 % to 7.8 % and 4.1  % (in yogurts); and, from 4.1 % to 2.0 % (in fermented milks), when compared to control. Thus, the pre-exposure of probiotics to stress conditions may impact not only the sensory and biochemical characteristics of fermented products, but also the bioaccessibility of nutrients and bioactive compounds.

Probiotic, fructooligosaccharide and yeast extract mixture improves gut health in rainbow trout, Oncorhynchus mykiss

The present study investigated the effects of a feed additive (FA) containing a probiotic consortium, fructooligosaccharide and yeast extract on growth performance, humoral immune responses, hepatic antioxidant parameters and intestine digestive enzymes, morphology and transcripts in rainbow trout, Oncorhynchus mykiss. The fish were reared for 8 weeks, feeding on diets containing 0 (CNT), 0.3 (0.3FA), 1 (1FA) and 2 (2FA) g/kg FA. The results showed that fish growth parameters were significantly and quadratically related to FA levels and FA treatments had better growth performance than CNT treatment. Intestinal amylase activity significantly increased in 2FA, whereas, intestinal protease activity increased in all FA treatments. Intestinal villus length and muscular layer thickness significantly increased in 0.3FA treatment. Blood leucocyte and lymphocyte counts, plasma lysozyme activity and hepatic glutathione content significantly increased in 0.3FA and 1FA treatments; whereas hepatic malondialdehyde significantly decreased in these treatments. Blood neutrophil and monocyte counts significantly increased in 0.3FA treatment, while plasma alternative complement activity significantly increased in 1FA treatments. Plasma bactericidal activities against Aeromonas hydrophila, Yersinia ruckeri and Streptococcus iniae, and intestinal expression of heat shock protein 70 and beta-defensin significantly increased in all FA treatments. The abundance of A. hydrophila, Y. ruckeri and S. iniae in fish gut significantly decreased in 0.3FA treatment; these bacteria were absent in the intestines of 1FA and 2FA treatments. The present results suggest that dietary 0.3-1 g/kg of FA can significantly improve growth performance, immune response, intestinal health and hepatic antioxidant capacity in rainbow trout.

Multifunctional Applications of Lactic Acid Bacteria: Enhancing Safety, Quality, and Nutritional Value in Foods and Fermented Beverages

Lactic Acid Bacteria (LAB) have garnered significant attention in the food and beverage industry for their significant roles in enhancing safety, quality, and nutritional value. As starter cultures, probiotics, and bacteriocin producers, LAB contributes to the production of high-quality foods and beverages that meet the growing consumer demand for minimally processed functional and health-promoting food products. Industrial food processing, especially in the fresh produce and beverage sector, is shifting to the use of more natural bioproducts in food production, prioritizing not only preservation but also the enhancement of functional characteristics in the final product. Starter cultures, essential to this approach, are carefully selected for their robust adaptation to the food environment. These cultures, often combined with probiotics, contribute beyond their basic fermentation roles by improving the safety, nutritional value, and health-promoting properties of foods. Thus, their selection is critical in preserving the integrity, quality, and nutrition of foods, especially in fresh produce and fruits and vegetable beverages, which have a dynamic microbiome. In addition to reducing the risk of foodborne illnesses and spoilage through the metabolites, including bacteriocins they produce, the use of LAB in these products can contribute essential amino acids, lactic acids, and other bioproducts that directly impact food quality. As a result, LAB can significantly alter the organoleptic and nutritional quality of foods while extending their shelf life. This review is aimed at highlighting the diverse applications of LAB in enhancing safety, quality, and nutritional value across a range of food products and fermented beverages, with a specific focus on essential metabolites in fruit and vegetable beverages and their critical contributions as starter cultures, probiotics, and bacteriocin producers.

The occurrence, role, and management strategies for phytic acid in foods

Phytic acid, a naturally occurring compound predominantly found in cereals and legumes, is the focus of this review. This review investigates its distribution across various food sources, elucidating its dual roles in foods. It also provides new insights into the change in phytic acid level during food storage and the evolving trends in phytic acid management. Although phytic acid can function as a potent color stabilizer, flavor enhancer, and preservative, its antinutritional effects in foods restrict its applications. In terms of management strategies, numerous treatments for degrading phytic acid have been reported, each with varying degradation efficacies and distinct mechanisms of action. These treatments encompass traditional methods, biological approaches, and emerging technologies. Traditional processing techniques such as soaking, milling, dehulling, heating, and germination appear to effectively reduce phytic acid levels in processed foods. Additionally, fermentation and phytase hydrolysis demonstrated significant potential for managing phytic acid in food processing. In the future, genetic modification, due to its high efficiency and minimal environmental impact, should be prioritized to downregulate the biosynthesis of phytic acid. The review also delves into the biosynthesis and metabolism of phytic acid and elaborates on the mitigation mechanism of phytic acid using biotechnology. The challenges in the application of phytic acid in the food industry were also discussed. This study contributes to a better understanding of the roles phytic acid plays in food and the sustainability and safety of the food industry.

Bacterial Degradation of Antinutrients in Foods: The Genomic Insight

Antinutrients, also known as anti-nutritional factors (ANFs), are compounds found in many plant-based foods that can limit the bioavailability of nutrients or can act as precursors to toxic substances. ANFs have controversial effects on human health, depending mainly on their concentration. While the positive effects of these compounds are well documented, the dangers they pose and the approaches to avoid them have not been discussed to the same extent. There is no dispute that many ANFs negatively alter the absorption of vitamins, minerals, and proteins in addition to inhibiting some enzyme activities, thus negatively affecting the bioavailability of nutrients in the human body. This review discusses the chemical properties, plant bioavailability, and deleterious effects of anti-minerals (phytates and oxalates), glycosides (cyanogenic glycosides and saponins), polyphenols (tannins), and proteinaceous ANFs (enzyme inhibitors and lectins). The focus of this study is on the possibility of controlling the amount of ANF in food through fermentation. An overview of the most common biochemical pathways for their microbial reduction is provided, showing the genetic basis of these phenomena, including the active enzymes, the optimal conditions of action, and some data on the regulation of their synthesis.

Effect of Air Classification and Enzymatic and Microbial Bioprocessing on Defatted Durum Wheat Germ: Characterization and Use as Bread Ingredient

Its high dietary fiber and protein contents and nutritional quality make defatted wheat germ (DWG) a valuable cereal by-product, yet its negative impact on food structure limits its use as a food ingredient. In this research, DWG underwent air classification, which identified two fractions with high fiber (HF) and low fiber/high protein (LF) contents, and a bioprocessing protocol, involving treatment with xylanase and fermentation with selected lactic acid bacterial strains. The degree of proteolysis was evaluated through electrophoretic and chromatographic techniques, revealing differences among fractions and bioprocessing options. Fermentation led to a significant increase in free amino acids (up to 6 g/kg), further enhanced by the combination with xylanase. When HF was used as an ingredient in bread making, the fiber content of the resulting bread exceeded 3.6 g/100 g, thus reaching the threshold required to make a "source of fiber" claim according to Regulation EC No.1924/2006. Meanwhile, all breads could be labeled a "source of protein" since up to 13% of the energy was provided by proteins. Overall, bioprocessed ingredients lowered the glycemic index (84 vs. 89) and increased protein digestibility (80 vs. 63%) compared to control breads. Technological and sensory analysis showed that the enzymatic treatment combined with fermentation also conferred a darker and more pleasant color to the bread crust, as well as better crumb porosity and elasticity.

Co-culture fermentation by Saccharomycopsis fibuligera and lactic acid bacteria improves bioactivity and aroma profile of wheat bran and the bran-containing Chinese steamed bread

Co-culture fermentation with yeast and lactic acid bacteria (LAB) exhibits advantages in improving the bioactivity and flavor of wheat bran compared to single-culture fermentation, showing application potentials in bran-containing Chinese steamed bread (CSB). To explore the effects of combination of yeast and different LAB on the bioactivity and flavor of fermented wheat bran, this study analyzed the physicochemical properties, phytate degradation capacity, antioxidant activities, and aroma profile of wheat bran treated with co-culture fermentation by Saccharomycopsis fibuligera and eight different species of LAB. Further, the phenolic acid composition, antioxidant activities, texture properties, aroma profile, and sensory quality of CSB containing fermented wheat bran were evaluated. The results revealed that co-culture fermentation brought about three types of volatile characteristics for wheat bran, including ester-feature, alcohol and acid-feature, and phenol-feature, and the representative strain combinations for these characteristics were S. fibuligera with Limosilactobacillus fermentum, Pediococcus pentosaceus, and Latilactobacillus curvatus, respectively. Co-culture fermentation by S. fibuligera and L. fermentum for 36 h promoted acidification with a phytate degradation rate reaching 51.70 %, and improved the production of volatile ethyl esters with a relative content of 58.47 % in wheat bran. Wheat bran treated with co-culture fermentation by S. fibuligera and L. curvatus for 36 h had high relative content of 4-ethylguaiacol at 52.81 %, and exhibited strong antioxidant activities, with ABTS•+ and DPPH• scavenging rates at 65.87 % and 69.41 %, respectively, and ferric reducing antioxidant power (FRAP) at 37.91 μmol/g. In addition, CSB containing wheat bran treated with co-culture fermentation by S. fibuligera and L. fermentum showed a large specific volume, soft texture, and pleasant aroma, and received high sensory scores. CSB containing wheat bran treated with co-culture fermentation by S. fibuligera and L. curvatus, with high contents of 4-ethylguaiacol, 4-vinylguaiacol, ferulic acid, vanillin, syringaldehyde, and protocatechualdehyde, demonstrated strong antioxidant activities. This study is beneficial to the comprehensive utilization of wheat bran resources and provides novel insights into the enhancement of functions and quality for CSB.

Importance of binary and ternary complex formation on the functional and nutritional properties of legume proteins in presence of phytic acid and calcium

Nowadays, legumes are considered as a good source of plant-based proteins to replace animal ones. They are more favorable regarding environmental aspects and health benefits, therefore many people consider moving toward a greener diet. Interestingly, recent consumer trends are promoting pea and faba bean as alternatives to soybean. Both are rich in protein and a good source of essential nutrients and minerals (calcium). However, these advantages can be partially impaired due to their high phytic acid content. This natural polyphosphate is a major antinutrient in plant-based foods, as it can bind minerals (particularly calcium) and proteins, thereby reducing their digestibility and subsequent bioavailability. Indeed, complexes formed are insoluble and limiting the absorption of nutrients, thus lowering the nutritional value of pulses. To understand and overcome these issues, the present review will refine specific mechanisms involved in assemblies between these three essential compounds in legumes as soluble/insoluble binary or ternary complexes. Molecular interactions are influenced by the environmental medium including pH, ionic strength and molar concentrations modulating the stability of these complexes during protein extraction. Protein/phytic acid/calcium complexes stability is of high relevance for food processing affecting not only structure but also functional and nutritional properties of proteins in legume-based foods.

Effective mitigation in the amount of acrylamide through enzymatic approaches

Acrylamide (AA), as a food-borne toxicant, is created at some stages of thermal processing in the starchy food through Maillard reaction, fatty food via acrolein route, and proteinous food using free amino acids pathway. Maillard reaction obviously takes place in thermal-based products, being responsible for specific sensory attributes; AA formation, thereby, is unavoidable during the thermal processing. Additionally, AA can naturally occur in soil and water supply. In order to reduce the levels of acrylamide in cooked foods, mitigation techniques can be separated into three different types. Firstly, starting materials low in acrylamide precursors can be used to reduce the acrylamide in the final product. Secondly, process conditions may be modified in order to decrease the amount of acrylamide formation. Thirdly, post-process intervention could be used to reduce acrylamide. Conventional or emerging mitigation techniques might negatively influence the pleasant features of heated foods. The current study summarizes the effect of enzymatic reaction induced by asparaginase, glucose oxidase, acrylamidase, phytase, amylase, and protease to possibly inhibit AA formation or progressively hydrolyze formed AA. Not only enzyme-assisted AA reduction could dramatically maintain bio-active compounds, but also no damaging impact has been reported on the sensorial and rheological properties of the final heated products. The enzyme engineering can be applied to ameliorate enzyme functionality through altering the amino acid sequence like site-specific mutagenesis and directed evolution, chemical modifications by covalent conjugation of L-asparaginase onto soluble/insoluble biocompatible polymers and immobilization. Moreover, it would be possible to improve the enzyme's physical, chemical, and thermal stability, recyclability and prevent enzyme overuse by applying engineered ones. In spite of enzymes' cost-effective and eco-friendly, promoting their large-scale usages for AA reduction in food application and AA bioremediation in wastewater and soil resources.

Application of enzymes for an eco-friendly approach to textile processing

Textile industry is one of the oldest industries existing from several centuries. Major concern of the industry is to design, produce, and distribute yarn, cloth, and clothing. Diverse physical and chemical operations are required in order to achieve this. Environmental concerns related to textile industry have attained attention all around the world as it is generating large amounts of effluents having various toxic agents and chemicals. Enzymes have been suggested as the best possible alternative to replace or reduce these hazardous and toxic chemicals. Enzymes like amylase, cellulase, catalase, protease, pectinase, laccase, and lipase have widely been used in textile manufacturing processes. Use of enzymatic approach is very promising as they are eco-friendly, produce high-quality products, and lead to the reduction of energy, water, and time. This review highlights the significance of different enzymes employed in the textile industry at various stages along with the conventional textile processing.

Integrative analysis of transcriptome and metabolome reveals probiotic effects on cecal metabolism in broilers

BACKGROUND

Probiotics play an important role in the host and have attracted widespread attention as an alternative to antibiotics. Arbor Acres broilers were used in the present experiment and fed different doses of compound probiotics at 1, 5, and 10 g kg^-1 . The effects of compound probiotics on broiler growth performance and cecal transcriptome and metabolome were investigated.

RESULTS

We discovered 425 differentially expressed genes (DEGs; upregulated: 256; downregulated: 169) in the cecal transcriptome study. These DEGs were assigned to fat metabolic pathways, such as the peroxisome proliferator-activated receptor (PPAR) signaling pathway, according to KEGG analysis. Probiotics downregulated LPL and upregulated PPARα expression in the cecum. In metabolome analysis of the cecum of cecum, we screened 86 differential metabolites and performed KEGG enrichment analysis of these metabolites. The KEGG analysis showed that these differentially expressed metabolites were annotated to nucleotide metabolism-related pathways, such as purine metabolism. In the cecum, probiotics upregulated the content of guanine, AMP, 3'-AMP, adenylosuccinate, deoxyguanosine, and ADP-ribose, whereas they downregulated the content of 5-hydroxyisourate. Comprehensive transcriptome and metabolome analysis revealed that glycolysis, gluconeogenesis, and glycerophospholipid metabolism pathways were jointly enriched in cecum of broilers fed a probiotic-containing diet.

CONCLUSION

This study provides valuable information for studying the regulation and gene metabolism network of probiotics on cecal metabolism in broilers. © 2022 Society of Chemical Industry.

"Masato de Yuca" and "Chicha de Siete Semillas" Two Traditional Vegetable Fermented Beverages from Peru as Source for the Isolation of Potential Probiotic Bacteria

In this work, two Peruvian beverages "Masato de Yuca," typical of the Amazonian communities made from cassava (Manihot esculenta), and "Chicha de Siete Semillas," made from different cereal, pseudo-cereal, and legume flours, were explored for the isolation of lactic acid bacteria after obtaining the permission of local authorities following Nagoya protocol. From an initial number of 33 isolates, 16 strains with different RAPD- and REP-PCR genetic profiles were obtained. In Chicha, all strains were Lactiplantibacillus plantarum (formerly Lactobacillus plantarum), whereas in Masato, in addition to this species, Limosilactobacillus fermentum (formerly Lactobacillus fermentum), Pediococcus acidilactici, and Weissella confusa were also identified. Correlation analysis carried out with their carbohydrate fermentation patterns and enzymatic profiles allowed a clustering of the lactobacilli separated from the other genera. Finally, the 16 strains were submitted to a static in vitro digestion (INFOGEST model) that simulated the gastrointestinal transit. Besides, their ability to adhere to the human epithelial intestinal cell line HT29 was also determined. Following both procedures, the best probiotic candidate was Lac. plantarum Ch13, a robust strain able to better face the challenging conditions of the gastrointestinal tract and showing higher adhesion ability to the intestinal epithelium in comparison with the commercial probiotic strain 299v. In order to characterize its benefit for human health, this Ch13 strain will be deeply studied in further works.

Effects of Fermented Food Consumption on Non-Communicable Diseases

The gastrointestinal flora consists of several microbial strains in variable combinations in both healthy and sick humans. To prevent the risk of the onset of disease and perform normal metabolic and physiological functions with improved immunity, a balance between the host and gastrointestinal flora must be maintained. Disruption of the gut microbiota triggered by various factors causes several health problems, which promote the progression of diseases. Probiotics and fermented foods act as carriers of live environmental microbes and play a vital role in maintaining good health. These foods have a positive effect on the consumer by promoting gastrointestinal flora. Recent research suggests that the intestinal microbiome is important in reducing the risk of the onset of various chronic diseases, including cardiac disease, obesity, inflammatory bowel disease, several cancers, and type 2 diabetes. The review provides an updated knowledge base about the scientific literature addressing how fermented foods influence the consumer microbiome and promote good health with prevention of non-communicable diseases. In addition, the review proves that the consumption of fermented foods affects gastrointestinal flora in the short and long term and can be considered an important part of the diet.

Impact of Lactobacillus apis on the antioxidant activity, phytic acid degradation, nutraceutical value and flavor properties of fermented wheat bran, compared to Saccharomyces cerevisiae and Lactobacillus plantarum

This study aimed to use a novel Lactobacillus strain (L. apis) isolated from the bee gut to develop a wheat bran (WB) deep-processing technology. Compared to the most popular strains (S. cerevisiae and L. plantarum), we found that L. apis had a greater ability to enhance the fermented WB antioxidant activity through hydroxyl radical scavenging, metal chelating ability, reducing power, and ferric reducing antioxidant power. While L. apis and L. plantarum had similar effects on DPPH^• and ABTS^•+ scavenging activities. This improvement in antioxidant activity has been associated with some metabolic compounds, such as sinapic acid, hydroferulic acid, pyruvic acid, neocostose, oxalic acid, salicylic acid, and schaftoside. Furthermore, L. apis degraded 48.33% of the phytic acid in WB, higher than S. cerevisiae (26.73%) and L. plantarum (35.89%). All strains improved the volatile profile of WB, and the fermented WB by each strain displayed a unique volatile composition. L. apis increased the level of conditional amino acids and branched-chain amino acids significantly. S. cerevisiae increased γ-aminobutyric acid the most, from 230.8 mg/L in unfermented samples to 609.8 mg/L in the fermented WB. While L. apis and L. plantarum also increased the level of γ-aminobutyric acid to 384.5 mg/L and 295.04 mg/L, respectively. Finally, we found that L. apis remarkably increased the content of organic acids and water-soluble vitamins in wheat bran.

State-of-the-Art Review on Engineering Uses of Calcium Phosphate Compounds: An Eco-Friendly Approach for Soil Improvement

Greenhouse gas emissions are a critical problem nowadays. The cement manufacturing sector alone accounts for 8% of all human-generated emissions, and as the world's population grows and globalization intensifies, this sector will require significantly more resources. In order to fulfill the need of geomaterials for construction and to reduce carbon dioxide emissions into the atmosphere, conventional approaches to soil reinforcement need to be reconsidered. Calcium phosphate compounds (CPCs) are new materials that have only recently found their place in the soil reinforcement field. Its eco-friendly, non-toxic, reaction pathway is highly dependent on the pH of the medium and the concentration of components inside the solution. CPCs has advantages over the two most common environmental methods of soil reinforcement, microbial-induced carbonate precipitation (MICP) and enzyme induced carbonate precipitation (EICP); with CPCs, the ammonium problem can be neutralized and thus allowed to be applied in the field. In this review paper, the advantages and disadvantages of the engineering uses of CPCs for soil improvement have been discussed. Additionally, the process of how CPCs perform has been studied and an analysis of existing studies related to soil reinforcement by CPC implementation was conducted.

The Impact of Insect Flour on Sourdough Fermentation-Fatty Acids, Amino-Acids, Minerals and Volatile Profile

Acheta domesticus (L.1758) has been recently accepted by the European Union as a novel food, being the third insect that has been approved for human consumption. Nowadays, researchers' attention is focused on exploiting new protein sustainable sources, and, therefore, insect flour has gained more and more interest. Organic acids, fatty acids, amino acids, aroma volatile compounds, and minerals were analyzed through HPLC-RID (High-performance liquid chromatography), GC-MS (Gas chromatography-mass spectrometry), LC-MS (Liquid chromatography-mass spectrometry), ITEX/GC-MS and AAS (Atomic Absorption Spectrophotometry), respectively. Fermentation of the insect flour with Lactobacillus plantarum ATCC 8014 strain (Lp) leads to an increase in organic acids such as lactic, acetic, and oxalic, whilst citric acid decreases its value. SFA (saturated fatty acids) and MUFA (monosaturated fatty acids) groups were positively influenced by Lp fermentation; meanwhile, PUFA (polysaturated fatty acids) decreased during fermentation. A positive trend was observed for amino acids, aroma volatile content, and minerals enhancement during insect sourdough fermentation, mainly at 24 h of fermentation. Acheta domesticus (A. domesticus) sourdough fermentation represents a new tool that needs to be further exploited aiming to improve the nutritional qualities of the final products.

Effect of Lactic Acid Fermentation on Legume Protein Properties, a Review

Legume proteins have a promising future in the food industry due to their nutritional, environmental, and economic benefits. However, their application is still limited due to the presence of antinutritional and allergenic compounds, their poor technological properties, and their unpleasant sensory characteristics. Fermentation has been traditionally applied to counteract these inconveniences. At present, lactic acid fermentation of legumes is attracting the attention of researchers and industry in relation to the development of healthier, tasty, and technologically adapted products. Hence, we aimed to review the literature to shed light on the effect of lactic acid fermentation on legume protein composition and on their nutritional, functional, technological, and sensorial properties. The antimicrobial activity of lactic acid bacteria during legume fermentation was also considered. The heterogenicity of raw material composition (flour, concentrate, and isolate), the diversity of lactic acid bacteria (nutriment requirements, metabolic pathways, and enzyme production), and the numerous possible fermenting conditions (temperature, time, oxygen, and additional nutrients) offer an impressive range of possibilities with regard to fermented legume products. Systematic studies are required in order to determine the specific roles of the different factors. The optimal selection of these criteria will allow one to obtain high-quality fermented legume products. Fermentation is an attractive technology for the development of legume-based products that are able to satisfy consumers’ expectations from a nutritional, functional, technological, and sensory point of view.

The Complex Role of Lactic Acid Bacteria in Food Detoxification

Toxic ingredients in food can lead to serious food-related diseases. Such compounds are bacterial toxins (Shiga-toxin, listeriolysin, Botulinum toxin), mycotoxins (aflatoxin, ochratoxin, zearalenone, fumonisin), pesticides of different classes (organochlorine, organophosphate, synthetic pyrethroids), heavy metals, and natural antinutrients such as phytates, oxalates, and cyanide-generating glycosides. The generally regarded safe (GRAS) status and long history of lactic acid bacteria (LAB) as essential ingredients of fermented foods and probiotics make them a major biological tool against a great variety of food-related toxins. This state-of-the-art review aims to summarize and discuss the data revealing the involvement of LAB in the detoxification of foods from hazardous agents of microbial and chemical nature. It is focused on the specific properties that allow LAB to counteract toxins and destroy them, as well as on the mechanisms of microbial antagonism toward toxigenic producers. Toxins of microbial origin are either adsorbed or degraded, toxic chemicals are hydrolyzed and then used as a carbon source, while heavy metals are bound and accumulated. Based on these comprehensive data, the prospects for developing new combinations of probiotic starters for food detoxification are considered.

Metabolomics of Rice Bran Differentially Impacted by Fermentation With Six Probiotics Demonstrates Key Nutrient Changes for Enhancing Gut Health

The consumption of rice bran has been shown to have a positive effect on nutritional status and prevention of chronic diseases related to hundreds of metabolites with bioactivity. Consumption after fermentation can lead to specific beneficial effects, yet is lacking complete characterization when fermented with diverse strains. The objective of this study was to examine the effect of fermentation on the rice bran metabolite profile. Bacterial probiotics (Bifidobacterium longum, Limosilactobacillus fermentum, Lacticaseibacillus paracasei, Lacticaseibacillus rhamnosus and, Escherichia coli) were used to ferment rice bran alone or after incubation with yeast probiotic Saccharomyces boulardii. Fermented rice bran was methanol extracted and analyzed by UPLC-MS/MS. The metabolome of the two fermentation types was deeply modified when compared with non-fermented rice bran. The two-step fermentation provided alternative substrate to the bacteria in a few cases. Key metabolites of high nutritional value (essential amino acids, vitamins) and gut health (arabinose, maltotriose) were identified.

Relevance of organ(s)-on-a-chip systems to the investigation of food-gut microbiota-host interactions

The ever greater understanding of the composition and function of the gut microbiome has provided new opportunities with respect to understanding and treating human disease. However, the models employed for in vitro and in vivo animal studies do not always provide the required insights. As a result, one such alternative in vitro cell culture based system, organ-on-a-chip technology, has recently attracted attention as a means of obtaining data that is representative of responses in humans. Organ-on-a-chip systems are designed to mimic the interactions of different tissue elements that were missing from traditional two-dimensional tissue culture. While they do not traditionally include a microbiota component, organ-on-a-chip systems provide a potentially valuable means of characterising the interactions between the microbiome and human tissues with a view to providing even greater accuracy. From a dietary perspective, these microbiota-organ-on-a-chip combinations can help researchers to predict how the consumption of specific foods and ingredients can impact on human health and disease. We provide an overview of the relevance and interactions of the gut microbiota and the diet in human health, we summarise the components involved in the organ-on-a-chip systems, how these systems have been employed for microbiota based studies and their potential relevance to study the interplay between food-gut microbiota-host interactions.

Effects of watermelon pulp fortification on maize mageu physicochemical and sensory acceptability

Mageu is a non-alcoholic fermented gruel processed from cereal grains, mostly maize and is widely consumed in the Southern African region. The refined maize meal used for mageu processing is limited in dietary fiber, B-vitamins, vitamin C, carotenoids, omega-3 fatty acids and minerals because of bran removal during milling. Fortification with plant carotenoid sources may be an effective method to supply potent antioxidants such as lycopene and beta-carotene that help preventing vitamin A deficiency related diseases. The objective of this study was to investigate the effects of three levels of watermelon pulp powder fortifications (5g, 10g, and 15g) on the physicochemical and sensory acceptability of maize mageu. Significant difference (p < 0.05) was found for crude protein, ash, titratable acidity, and total carotenoid contents among the mageu samples. The percentage protein, ash, titratable acidity (TA), vitamin C (mg/100g) and total carotenoids (TC) (μg/g) contents for the mageu samples ranged between 10.60-13.70, 0.53-0.86, 0.08-0.15, 8.81-17.60 and 0.00-51.60, respectively. There was an increase in the protein, ash, TA, vitamin C and TC contents with an increasing level of watermelon pulp fortification. When watermelon pulp fortification increased to 15g, total carotenoids content increased significantly which shows the potential to fortify mageu with lycopene, the major carotenoid in the watermelon pulp, as well beta-carotene a pro-vitamin A carotenoid. Furthermore, the sensory attributes of the mageu sample fortified with 15g watermelon pulp was liked significantly (p < 0.05) more by a consumer panel. The study showed the potential of an acceptable maize mageu fortification with watermelon pulp powder to increase its nutritional and bioactive compounds, particularly lycopene.

Fermentation of Jamaican Cherries Juice Using Lactobacillus plantarum Elevates Antioxidant Potential and Inhibitory Activity against Type II Diabetes-Related Enzymes

Jamaican cherry (Muntinga calabura Linn.) is tropical tree that is known to produce edible fruit with high nutritional and antioxidant properties. However, its use as functional food is still limited. Previous studies suggest that fermentation with probiotic bacteria could enhance the functional properties of non-dairy products, such as juices. In this study, we analyze the metabolite composition and activity of Jamaican cherry juice following fermentation with Lactobacillus plantarum FNCC 0027 in various substrate compositions. The metabolite profile after fermentation was analyzed using UPLC-HRMS-MS and several bioactive compounds were detected in the substrate following fermentation, including gallic acid, dihydrokaempferol, and 5,7-dihydroxyflavone. We also found that total phenolic content, antioxidant activities, and inhibition of diabetic-related enzymes were enhanced after fermentation using L. plantarum. The significance of its elevation depends on the substrate composition. Overall, our findings suggest that fermentation with L. plantarum FNCC 0027 can improve the functional activities of Jamaican cherry juice.

Enhancing Micronutrients Bioavailability through Fermentation of Plant-Based Foods: A Concise Review

Plant-based foods are rich sources of vitamins and essential micronutrients. For the proper functioning of the human body and their crucial role, trace minerals (iron, zinc, magnesium, manganese, etc.) are required in appropriate amounts. Cereals and pulses are the chief sources of these trace minerals. Despite these minerals, adequate consumption of plant foods cannot fulfill the human body’s total nutrient requirement. Plant foods also contain ample amounts of anti-nutritional factors such as phytate, tannins, phenols, oxalates, etc. These factors can compromise the bioavailability of several essential micronutrients in plant foods. However, literature reports show that fermentation and related processing methods can improve nutrient and mineral bioavailability of plant foods. In this review, studies related to fermentation methods that can be used to improve micronutrient bioavailability in plant foods are discussed.

Pulse Probiotic Superfood as Iron Status Improvement Agent in Active Women-A Review

Active women or women of reproductive age (15–49 years old) have a high risk of suffering from anaemia. Anaemia is not solely caused by iron deficiency, however, the approaches to improve iron status in both cases are greatly related. Improving the iron status of active women can be done by dietary intervention with functional food. This review aims to provide insights about the functional food role to increase iron absorption in active women and the potency of pulse probiotic superfood development in dry matrices. Results showed that the beneficial effect of iron status is significantly improved by the synergic work between probiotic and prebiotic. Furthermore, chickpeas and lentils are good sources of prebiotic and the consumption of pulses are related with 21st century people’s intention to eat healthy food. There are wide possibilities to develop functional food products incorporated with probiotics to improve iron status in active woman.

Uncovering Prospective Role and Applications of Existing and New Nutraceuticals from Bacterial, Fungal, Algal and Cyanobacterial, and Plant Sources

Nutraceuticals are a category of products more often associated with food but having pharmaceuticals property and characteristics. However, there is still no internationally accepted concept of these food-pharmaceutical properties, and their interpretation can differ from country to country. Nutraceuticals are used as part of dietary supplements in most countries. They can be phytochemicals which are biologically active and have health benefits. These can be supplied as a supplement and/or as a functional food to the customer. For human health and longevity, these materials are likely to play a vital role. Consumption of these items is typical without a therapeutic prescription and/or supervision by the vast majority of the public. The development of nutraceuticals can be achieved through many bioresources and organisms. This review article will discuss the current research on nutraceuticals from different biological sources and their potential use as an agent for improving human health and well-being, as well as the gaps and future perspective of research related to nutraceutical development.

The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on fermented foods

An expert panel was convened in September 2019 by The International Scientific Association for Probiotics and Prebiotics (ISAPP) to develop a definition for fermented foods and to describe their role in the human diet. Although these foods have been consumed for thousands of years, they are receiving increased attention among biologists, nutritionists, technologists, clinicians and consumers. Despite this interest, inconsistencies related to the use of the term 'fermented' led the panel to define fermented foods and beverages as "foods made through desired microbial growth and enzymatic conversions of food components". This definition, encompassing the many varieties of fermented foods, is intended to clarify what is (and is not) a fermented food. The distinction between fermented foods and probiotics is further clarified. The panel also addressed the current state of knowledge on the safety, risks and health benefits, including an assessment of the nutritional attributes and a mechanistic rationale for how fermented foods could improve gastrointestinal and general health. The latest advancements in our understanding of the microbial ecology and systems biology of these foods were discussed. Finally, the panel reviewed how fermented foods are regulated and discussed efforts to include them as a separate category in national dietary guidelines.

Evaluation of curcumin and copper acetate against Salmonella Typhimurium infection, intestinal permeability, and cecal microbiota composition in broiler chickens

BACKGROUND

Interest in the use of natural feed additives as an alternative to antimicrobials in the poultry industry has increased in recent years because of the risk of bacterial resistance. One of the most studied groups are polyphenolic compounds, given their advantages over other types of additives and their easy potentiation of effects when complexes are formed with metal ions. Therefore, the objective of the present study was to evaluate the impact of dietary supplementation of copper acetate (CA), curcumin (CR), and their combination (CA-CR) against Salmonella Typhimurium colonization, intestinal permeability, and cecal microbiota composition in broiler chickens through a laboratory Salmonella infection model. S. Typhimurium recovery was determined on day 10 post-challenge by isolating Salmonella in homogenates of the right cecal tonsil (12 chickens per group) on Xylose Lysine Tergitol-4 (XLT-4) with novobiocin and nalidixic acid. Intestinal integrity was indirectly determined by the fluorometric measurement of fluorescein isothiocyanate dextran (FITC-d) in serum samples from blood obtained on d 10 post-S. Typhimurium challenge. Finally, microbiota analysis was performed using the content of the left caecal tonsil of 5 chickens per group by sequencing V4 region of 16S rRNA gene.

RESULTS

The results showed that in two independent studies, all experimental treatments were able to significantly reduce the S. Typhimurium colonization in cecal tonsils (CT, P < 0.0001) compared to the positive control (PC) group. However, only CA-CR was the most effective treatment in reducing S. Typhimurium counts in both independent studies. Furthermore, the serum fluorescein isothiocyanate dextran (FITC-d) concentration in chickens treated with CR was significantly lower when compared to PC (P = 0.0084), which is related to a decrease in intestinal permeability and therefore intestinal integrity. The effect of dietary treatments in reducing Salmonella was further supported by the analysis of 16S rRNA gene sequences using Linear discriminant analysis effect size (LEfSe) since Salmonella was significantly enriched in PC group (LDA score > 2.0 and P < 0.05) compared to other groups. In addition, Coprobacillus, Eubacterium, and Clostridium were significantly higher in the PC group compared to other treatment groups. On the contrary, Fecalibacterium and Enterococcus in CR, unknown genus of Erysipelotrichaceae at CA-CR, and unknown genus of Lachnospiraceae at CA were significantly more abundant respectively.

CONCLUSIONS

CR treatment was the most effective treatment to reduce S. Typhimurium intestinal colonization and maintain better intestinal homeostasis which might be achieved through modulation of cecal microbiota.

Plant-Based Alternatives to Yogurt: State-of-the-Art and Perspectives of New Biotechnological Challenges

Due to the increasing demand for milk alternatives, related to both health and ethical needs, plant-based yogurt-like products have been widely explored in recent years. With the main goal to obtain snacks similar to the conventional yogurt in terms of textural and sensory properties and ability to host viable lactic acid bacteria for a long-time storage, several plant-derived ingredients (e.g., cereals, pseudocereals, legumes, and fruits) as well as technological solutions (e.g., enzymatic and thermal treatments) have been investigated. The central role of fermentation in yogurt-like production led to specific selections of lactic acid bacteria strains to be used as starters to guarantee optimal textural (e.g., through the synthesis of exo-polysaccharydes), nutritional (high protein digestibility and low content of anti-nutritional compounds), and functional (synthesis of bioactive compounds) features of the products. This review provides an overview of the novel insights on fermented yogurt-like products. The state-of-the-art on the use of unconventional ingredients, traditional and innovative biotechnological processes, and the effects of fermentation on the textural, nutritional, functional, and sensory features, and the shelf life are described. The supplementation of prebiotics and probiotics and the related health effects are also reviewed.

Production and characterization of a novel, thermotolerant fungal phytase from agro-industrial byproducts for cattle feed

OBJECTIVE

The application of phytases helps in releasing bound phosphorus and other nutrients in cattle feed eventually reducing the need for supplementations. However, high production cost owing to the unavailability of cheaper sources of phytases has limited their usage in developing countries. Herein, firstly isolation, identification of a phytase from fungal isolate, Aspergillus niger NT7 was carried out followed by optimizing of all production parameters, through solid-state fermentation (SSF). Secondly, crude phytase was characterized and potential applicability of crude phytase was evaluated for dephytinization of wheat bran.

RESULTS

The highest phytase production (208.30 ± 0.22 U/gds) was achieved using wheat bran as cheap agro-industrial substrate for SSF. The various physiological parameters were optimized including inoculum age and level (3-day old inoculum and 15 × 10⁷ spores/ml), temperature (35 °C), a moistening agent (distilled water), medium pH (5), and supplementation of various biochemicals like sugar (Mannitol), nitrogen (ammonium sulphate) and detergent (Tween 80). Process optimization through one variable at a time (OVAT) approach increased the difference in productivity to more than 200%. The crude phytase of A. niger NT7 was thermostable, with optimal activity at 60 °C and also displayed optimal activity over a broad range of acidic pH. Further, enhancement in phytase activity was found specifically in the presence of Ca²⁺, Zn²⁺, and Co²⁺ ions, while other metal ions including Fe²⁺, Fe³⁺, Mn²⁺, Mg²⁺and Cu²⁺ inhibited its activity. Finally, the phytase showed efficient and sustained release of inorganic phosphate, proteins, and reducing sugars (> 60 h) from livestock feed.

CONCLUSION

Overall, our report highlights the production of an efficient and thermotolerant phytase with potential as a low-cost animal feed supplement.

Impact of Fermentation and Phytase Treatment of Pea-Oat Protein Blend on Physicochemical, Sensory, and Nutritional Properties of Extruded Meat Analogs

Plant materials that are used for the production of extruded meat analogs are often nutritionally incomplete and also contain antinutrients, thus there is a need to explore alternative plant proteins and pre-treatments. This study demonstrates application of phytase and fermentation to a pea-oat protein blend with a good essential amino acid profile and subsequent texturization using extrusion cooking. Enzymatic treatment reduced the content of antinutrient phytic acid by 32%. Extrusion also degraded phytic acid by up to 18%, but the effect depended on the material. Differences in physicochemical, sensorial, and textural properties between untreated and phytase-treated extruded meat analogs were small. In contrast, fermented material was more difficult to texturize due to degradation of macromolecules; physicochemical and textural properties of extrudates were markedly different; sensory analysis showed enhancement of flavor, but also detected an increase in some unwanted taste attributes (bitterness, cereal and off-taste). Phytic acid was not degraded by fermentation. Analysis of volatile compounds showed extrusion eliminated volatiles from the raw material but introduced Maillard reaction products. Overall, phytase treatment and fermentation demonstrated the potential for application in extruded meat analogs but also highlighted the necessity of optimization of process conditions.

The food-gut axis: lactic acid bacteria and their link to food, the gut microbiome and human health

Lactic acid bacteria (LAB) are present in foods, the environment and the animal gut, although fermented foods (FFs) are recognized as the primary niche of LAB activity. Several LAB strains have been studied for their health-promoting properties and are employed as probiotics. FFs are recognized for their potential beneficial effects, which we review in this article. They are also an important source of LAB, which are ingested daily upon FF consumption. In this review, we describe the diversity of LAB and their occurrence in food as well as the gut microbiome. We discuss the opportunities to study LAB diversity and functional properties by considering the availability of both genomic and metagenomic data in public repositories, as well as the different latest computational tools for data analysis. In addition, we discuss the role of LAB as potential probiotics by reporting the prevalence of key genomic features in public genomes and by surveying the outcomes of LAB use in clinical trials involving human subjects. Finally, we highlight the need for further studies aimed at improving our knowledge of the link between LAB-fermented foods and the human gut from the perspective of health promotion.

Effect of Rice Flour Fermentation with Lactobacillus spicheri DSM 15429 on the Nutritional Features of Gluten-Free Muffins

Lactobacillus Spicheri DSM 15429 strain was used to ferment rice flour, aiming at exploiting its influence on the amino-acids, minerals, lactic acid, total phenols, and antioxidant activity of the rice sourdough and gluten-free muffins. Gluten-free muffins were prepared by using 15% rice sourdough fermented with the above strain of lactic acid bacteria and compared with rice spontaneous fermentation. Methods like LC-MS (Liquid chromatography–mass spectrometry), AA (atomic absorption), HPLC (High-performance liquid chromatography), Folin–Ciocalteu, and 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity (DPPH) were used to fulfill the aim of the study. The addition of rice sourdough fermented with LAB was reflected in the chemical composition of the final baked good, improving its amount on bioactive compounds such as amino acids, mineral bioavailability, total phenols, and antioxidant activity. Total phenols and antioxidant activity increased their amount by 70.53% and 73.70%, respectively, meanwhile, lactic acid, minerals, and amino-acids increased their values at least twice. Thus, rice fermented with Lactobacilus spicheri DSM 15429 strain could be a tool to further increase the nutritional value of gluten-free baked products.

Bio-functional properties of probiotic Lactobacillus: current applications and research perspectives

Lactic acid bacteria as a starter culture are very important component in the fermentation process of dairy and food industry. Application of lactic acid bacteria as probiotic bacteria adds more functionality to the developed product. Gut colonizing bacteria have attractive benefits related to human health. Bio-functional properties such as antimicrobial activity, anti-inflammatory, ACE-inhibitory, antioxidant, antidiarrheal, antiviral, immunomodulatory, hypocholesterolemic, anti-diabetic and anti-cancer activities are the most applicable research areas of lactic acid bacteria. Different strains of Lactobacillus are generally consumed as probiotics and colonize the gastrointestinal tract. Sometimes these bacteria may possess antimicrobial activity and may positively influence the effect of antibiotics. Use of Lactobacillus spp. for the development of functional foods is one of the promising areas of current research and applications. Individual bacterial species have unique biological activity, which may vary from strains to strains and identification of this uniqueness could be helpful in the development of functional and therapeutic food products.

Selection of Wild Lactic Acid Bacteria Strains as Promoters of Postbiotics in Gluten-Free Sourdoughs

The occurrence of inflammatory responses in humans is frequently associated with food intolerances and is likely to give rise to irritable bowel disease. The use of conventional or unconventional flours to produce gluten-free baking doughs brings important technological and nutritional challenges, and the use of the sourdough biotechnology has the potential to overcome such limitations. In addition, the typical metabolic transformations carried out by Lactic Acid Bacteria (LAB) can become an important biotechnological process for the nutritional fortification and functionalization of sourdoughs due to the resulting postbiotics. In such a context, this research work aimed at isolating and selecting new LAB strains that resort to a wide range of natural environments and food matrices to be ultimately employed as starter cultures in gluten-free sourdough fermentations. Nineteen LAB strains belonging to the genera of Lactobacillus, Leuconostoc, Pediococcus, and Streptococcus were isolated, and the selection criteria encompassed their acidification capacity in fermentations carried out on chickpea, quinoa, and buckwheat flour extracts; the capacity to produce exopolysaccharides (EPS); and the antimicrobial activity against food spoilage molds and bacteria. Moreover, the stability of the LAB metabolites after the fermentation of the gluten-free flour extracts submitted to thermal and acidic treatments was also assessed.