Lactic acid fermentation of legume seed sprouts as a method of increasing the content of isoflavones and reducing microbial contamination

Transformative effects of lactic acid fermentation on maize and quality protein maize: Phytochemical characterization, functional properties, and structural features

Background and Objective

Fermentation has a huge potential to improve the nutritional and functional properties by using the biological activity of the grain itself. The current study was performed to optimize the conditions for the fermentation of Quality Protein Maize (QPM) and maize further; the impact of fermentation treatment on the bio‐techno‐functional properties of QPM and maize flour was assessed.

Findings

The technological properties, including oil absorption capacity, water solubility index, emulsion activity and stability, foaming capacity and stability, protein solubility, gel consistency, and least gelation concentration, were found to be increased with the fermentation treatment, while water absorption capacity, paste clarity, and swelling power observed a decline. The findings suggested elevated levels of all the bioactive constituents with the fermentation process. The modulations at the molecular level were confirmed by the scanning electron micrographs of fermented flour. Further, changes in the peaks of Fourier transform infrared spectra and the emergence of new peaks were also reported.

Conclusions

The fermentation treatment altered the techno‐functional properties, bioactive constituents, macromolecular structure, and molecular interactions of QPM and maize flour.

Significance and Novelty

Limited literature is available dedicated to the assessment of the nutritional, techno‐functional, and phytochemical components in QPM and maize as influenced by the fermentation process. Further, changes in the structural and molecular interactions in the flour components due to fermentation treatment have not been studied comprehensively.

Dietary Polyphenols, Food Processing and Gut Microbiome: Recent Findings on Bioavailability, Bioactivity, and Gut Microbiome Interplay

Polyphenols are organic chemical compounds naturally present in plants, renowned for their anti-inflammatory, antioxidant, immunomodulatory, anticancer, and cardiovascular protective properties. Their bioactivity and bioavailability can vary widely depending on the methods of food processing and interactions with the gut microbiome. These factors can induce changes in polyphenols, affecting their ability to achieve their intended health benefits. Thus, it is essential to develop and apply food processing methods that optimize polyphenol content while maintaining their bioactivity and bioavailability. This review aims to explore how various food processing techniques affect the quantity, bioactivity, and bioavailability of polyphenols, as well as their interactions with the gut microbiome, which may ultimately determine their health effects.

Understanding the nutritional benefits through plant proteins-probiotics interactions: mechanisms, challenges, and perspectives

The nutritional benefits of combining probiotics with plant proteins have sparked increasing research interest and drawn significant attention. The interactions between plant proteins and probiotics demonstrate substantial potential for enhancing the functionality of plant proteins. Fermented plant protein foods offer a unique blend of bioactive components and beneficial microorganisms that can enhance gut health and combat chronic diseases. Utilizing various probiotic strains and plant protein sources opens doors to develop innovative probiotic products with enhanced functionalities. Nonetheless, the mechanisms and synergistic effects of these interactions remain not fully understood. This review aims to delve into the roles of promoting health through the intricate interplay of plant proteins and probiotics. The regulatory mechanisms have been elucidated to showcase the synergistic effects, accompanied by a discussion on the challenges and future research prospects. It is essential to recognize that the interactions between plant proteins and probiotics encompass multiple mechanisms, highlighting the need for further research to address challenges in achieving a comprehensive understanding of these mechanisms and their associated health benefits.

Changes in Chemical Composition of Lentils, Including Gamma-Aminobutyric Acid and Volatile Compound Formation during Submerged and Solid-State Fermentation with Pediococcus acidilactici

The aim of this study was to evaluate and compare the characteristics of non-treated and fermented [via submerged (SMF) and solid-state (SSF) fermentation using Pediococcus acidilactici] lentils (Lens culinaris) grown either in pure stands (L) or relay intercropped with winter rye (LR). It was observed that the lentils were suitable substrate for lacto-fermentation. Most of the free amino acid concentrations increased in lentils after both fermentations. The highest concentration of γ-aminobutyric acid was found in SSF LR samples. However, fermentation led to higher biogenic amines (BA) content in lentils. The most abundant fatty acid in lentils was C18:2. SSF lentils showed more complex volatile compound (VC) profiles (with between nine and seventeen new VCs formed), whereas, in SMF samples, between two and five newly VCs were formed. When comparing lentil grown types, L contained significantly higher concentrations of Na, K, Ca, P, Mn, and Se, while LR contained significantly higher concentrations of Fe and Ni. To sum up, fermentation with lactic acid bacteria (LAB) contributed to the improved biological value of lentils; still, the quantity of BA needs to be considered. Further investigations into the P. acidilactici metabolism of certain compounds (such as phenolic and antinutritional compounds) in lentils during fermentation ought to be carried out.

The effect of seed germination and Bacillus spp. on the ripening of plant cheese analogs

Consumer demand for plant cheeses is increasing, but challenges of improving both flavor and quality remain. This study investigated the microbiological and physicochemical impact of seed germination and fermentation with Bacillus velezensis and Bacillus amyloliquefaciens on the ripening of plant cheese analogs. Chlorine treatment or addition of Lactiplantibacillus plantarum and Lactococcus lactis controlled microbial growth during seed germination. Lp. plantarum and Lc. lactis also served as starter cultures for the acidification of soy and lupine milk and were subsequently present in the unripened plant cheese as dominant microbes. Acidification also inhibited the growth and metabolic activity of bacilli but Bacillus spores remained viable throughout ripening. During plant cheese ripening, Lc. lactis was inactivated before Lp. plantarum and the presence of bacilli during seed germination delayed Lc. lactis inactivation. Metagenomic sequencing of full-length 16S rRNA gene amplicons confirmed that the relative abundance of the inoculated strains in each ripened cheese sample exceeded 99%. Oligosaccharides including raffinose, stachyose, and verbascose were rapidly depleted in the initial stage of ripening. Both germination and the presence of bacilli during seed germination had impact on polysaccharide hydrolysis during ripening. Bacilli but not seed germination enhanced proteolysis of plant cheese during ripening. In conclusion, the use of germination with lactic acid bacteria in combination with Bacillus spp. exhibited the potential to improve the quality of ripened plant cheeses with a positive effect on the reduction of hygienic risks.

IMPORTANCE

The development of novel plant-based fermented food products for which no traditional templates exist requires the development of starter cultures. Although the principles of microbial flavor formation in plant-based analogs partially overlap with dairy fermentations, the composition of the raw materials and thus likely the selective pressure on the activity of starter cultures differs. Experiments that are described in this study explored the use of seed germination, the use of lactic acid bacteria, and the use of bacilli to reduce hygienic risks, to acidify plant milk, and to generate taste-active compounds through proteolysis and fermentative conversion of carbohydrates. The characterization of fermentation microbiota by culture-dependent and culture-independent methods also confirmed that the starter cultures used were able to control microbial communities throughout 90 d of ripening. Taken together, the results provide novel tools for the development of plant-based analogs of fermented dairy products.

New horizon to the world of gut microbiome: seeds germination

The second brain of humans has been known as the microbiome. The microbiome is a dynamic network composed of commensal bacteria, archaea, viruses, and fungi colonized in the human gastrointestinal tract. They play a vital role in human health by metabolizing components, maturation of the immune system, and taking part in the treatment of various diseases. Two important factors that can affect the gut microbiome's composition and/or function are the food matrix and methods of food processing. Based on scientific research, the consumption of whole grains can make positive changes in the gut microbiota. Seeds contain different microbiota-accessible substrates that can resist digestion in the upper gastrointestinal tract. Seed germination is one of the simplest and newest food processing approaches to improve seeds' bioavailability and overall nutritional value. During germination, the dormant hydrolytic seed's enzymes have been activated and then metabolize the macromolecules. The quality and quantity of bioactive compounds like prebiotics, fiber, phenolic compounds (PC), total free amino acids, and γ-aminobutyric acid (GABA) can increase even up to 4-10 folds in some cases. These components stimulate the survival and growth of healthful bacteria like probiotics and boost their activity. This effect depends on several parameters, e.g., germination environmental conditions. This review aims to provide up-to-date and latest research about promoting bioactive components during seed germination and investigating their impacts on gut microbiota to understand the possible direct and indirect effects of seed germination on the microbiome and human health.

Effects of Fermentation on Bioactivity and the Composition of Polyphenols Contained in Polyphenol-Rich Foods: A Review

Polyphenols, as common components with various functional activities in plants, have become a research hotspot. However, researchers have found that the bioavailability and bioactivity of plant polyphenols is generally low because they are usually in the form of tannins, anthocyanins and glycosides. Polyphenol-rich fermented foods (PFFs) are reported to have better bioavailability and bioactivity than polyphenol-rich foods, because polyphenols are used as substrates during food fermentation and are hydrolyzed into smaller phenolic compounds (such as quercetin, kaempferol, gallic acid, ellagic acid, etc.) with higher bioactivity and bioavailability by polyphenol-associated enzymes (PAEs, e.g., tannases, esterases, phenolic acid decarboxylases and glycosidases). Biotransformation pathways of different polyphenols by PAEs secreted by different microorganisms are different. Meanwhile, polyphenols could also promote the growth of beneficial bacteria during the fermentation process while inhibiting the growth of pathogenic bacteria. Therefore, during the fermentation of PFFs, there must be an interactive relationship between polyphenols and microorganisms. The present study is an integration and analysis of the interaction mechanism between PFFs and microorganisms and is systematically elaborated. The present study will provide some new insights to explore the bioavailability and bioactivity of polyphenol-rich foods and greater exploitation of the availability of functional components (such as polyphenols) in plant-derived foods.

The Comparative Effect of Lactic Acid Fermentation and Germination on the Levels of Neurotoxin, Anti-Nutrients, and Nutritional Attributes of Sweet Blue Pea (Lathyrus sativus L.)

Grass pea (Lathyrus sativus L.), an indigenous legume of the subcontinental region, is a promising source of protein and other nutrients of health significance. Contrarily, a high amount of β-N-oxalyl-l-α,β-diaminopropionic acid (β-ODAP) and other anti-nutrients limits its wider acceptability as healthier substitute to protein of animal and plant origin. This study was aimed at investigating the effect of different processing techniques, viz. soaking, boiling, germination, and fermentation, to improve the nutrient-delivering potential of grass pea lentil and to mitigate its anti-nutrient and toxicant burden. The results presented the significant (p < 0.05) effect of germination on increasing the protein and fiber content of L. sativus from 22.6 to 30.7% and 15.1 to 19.4%, respectively. Likewise, germination reduced the total carbohydrate content of the grass pea from 59.1 to 46%. The highest rate of reduction in phytic acid (91%) and β-ODAP (37%) were observed in germinated grass pea powder, whereas fermentation anticipated an 89% reduction in tannin content. The lactic acid fermentation of grass pea increased the concentration of calcium, iron, and zinc from 4020 to 5100 mg/100 g, 3.97 to 4.35 mg/100 g, and 3.52 to 4.97 mg/100 g, respectively. The results suggest that fermentation and germination significantly (p < 0.05) improve the concentration of essential amino acids including threonine, leucine, histidine, tryptophan, and lysine in L. sativus powder. This study proposes lactic acid fermentation and germination as safer techniques to improve the nutrient-delivering potential of L. sativus and suggests processed powders of the legume as a cost-effective alternative to existing plant proteins.

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.

Anti-nutrient & bioactive profile, in vitro nutrient digestibility, techno-functionality, molecular and structural interactions of foxtail millet (Setaria italica L.) as influenced by biological processing techniques

The present investigation aimed at assessing the impact of biological processing techniques on bio-and techno-functional characteristics of foxtail millet (Setaria italica L.). Grains were exposed to soaking, germination, fermentation and combination of aforesaid treatments and significant variation (p < 0.05) in anti-nutritional factors, in vitro starch and protein digestibility, bioactive constituents and associated antioxidant potential was noted. Bioprocessed flours were characterized by altered functional properties due to hydrolytic action of activated enzymes. ATR-FTIR spectra and X-ray diffraction patterns revealed structural variation in macromolecular arrangement, synthesis of bioactive compounds in bioprocessed flours and slight reduction in the crystallinity of starch molecules. Bioprocessed flours exhibited degraded protein matrix; however, only fermentation and combination treatments caused hydrolysis of granular starch. Principal component analysis was employed to validate the differences in processing treatments and observations. The results are suggestive that bioprocessed flours could serve as potential ingredients with improved techno-and bio-functionality in valorized cereal products.

Legumes and Legume-Based Beverages Fermented with Lactic Acid Bacteria as a Potential Carrier of Probiotics and Prebiotics

Fermentation is widely used in the processing of dairy, meat, and plant products. Due to the growing popularity of plant diets and the health benefits of consuming fermented products, there has been growing interest in the fermentation of plant products and the selection of microorganisms suitable for this process. The review provides a brief overview of lactic acid bacteria (LAB) and their use in fermentation of legumes and legume-based beverages. Its scope also extends to prebiotic ingredients present in legumes and legume-based beverages that can support the growth of LAB. Legumes are a suitable matrix for the production of plant-based beverages, which are the most popular products among dairy alternatives. Legumes and legume-based beverages have been successfully fermented with LAB. Legumes are a natural source of ingredients with prebiotic properties, including oligosaccharides, resistant starch, polyphenols, and isoflavones. These compounds provide a broad range of important physiological benefits, including anti-inflammatory and immune regulation, as well as anti-cancer properties and metabolic regulation. The properties of legumes make it possible to use them to create synbiotic food, which is a source of probiotics and prebiotics.

Antioxidant and tyrosinase inhibitory activities of traditional fermented Rosa from Dali Bai communities, Northwest Yunnan, China

Traditional fermented Rosa (TFR) is a typical food and medical product among the Dali Bai people, and its popularity is growing. A few studies have looked into TFR's medicinal advantages, linked germplasm resources, traditional processing procedures, and functional food qualities. Our goal was to look into Rosa's traditional processing, examine the dominant strains in TFR, and prove how these strains affected antioxidant and tyrosinase inhibitory activities. We used a snowball selection strategy to pick 371 informants for a semi-structured interview, supplemented with direct observations and sample collection. A microbial strain was isolated and identified from a TFR sample collected in the field. We synthesized TFR in the lab using the traditional way. Both of 2, 2-diphenyl-1 picrylhydrazyl (DPPH) free radical scavenging and tyrosinase inhibitory properties of the fermented solution of Rosa 'Dianhong' have been tested in this study. Altogether 15 species belonging to the genus Rosa, which are utilized in herbal medicine and fermented foods. Rosa 'Dianhong' was the Bai community's principal species with considerable cultural value and consumption. Raw Rosa petals included 15 major flavonoids and phenols, which were identified as TFR's active components. TFR-1 was discovered to be the dominating microbial strain in TFR, increasing total phenolic and flavonoid content in the fermented solution of Rosa 'Dianhong' by 0.45 mg GAE/ml and 0.60 mg RE/ml, respectively, after 30 days. TFR-1 also exhibited promising activity in terms of DPPH free radical scavenging and tyrosinase inhibition. TFR showed potent antioxidant and free-radical scavenger properties and is beneficial in skincare and nutrition, according to the findings. TFR's medicinal and edible properties suggest that it could be used as a cosmetic or nutraceutical product.

The influence of probiotic fermentation on the active compounds and bioactivities of walnut flowers

In this study, the walnut flowers were fermented using five different probiotics, including two Lactobacillus plantarum, one Lactobacillus bulgaricus, one Lactobacillus casei, and one Lactobacillus rhamnosus. The chemical compositions, antioxidant capacities, and α-glucosidase inhibitory abilities of walnut flowers during fermentation processes were evaluated. The results showed that all the active compounds and bioactivities of the walnut flowers were significantly decreased after 7 days of fermentation, whereas a short-term fermentation (1-3 days) enhanced their bioactivities. Compared to the unfermented sample, L. plantarum (ATCC 8014) and L. rhamnosus (ATCC 53013) increased the ABTS (1.22 and 1.30 times higher) and DPPH radical scavenging activities (up to 1.23 and 1.04 times), respectively. L. plantarum (SWFU D16), L. plantarum (ATCC 8014), and L. rhamnosus (ATCC 53013) improved the ferric reducing antioxidant power which was 110.98%, 133.16%, and 104.76% of the unfermented sample. All five probiotics promoted the α-glucosidase inhibitory ability of walnut flowers (maximum 2.18-fold increase). Three phenolic acids and five flavonoids in the fermentation broth were identified by HPLC, where catechin, epicatechin, and catechin gallate were the dominant components. HPLC results demonstrated that these compounds were degraded and transformed in varying degrees under the effects of probiotics. Taken together, a short-term probiotic fermentation could change the active compounds of the walnut flowers and improve their bioactivities. L. plantarum (ATCC 8014) and L. rhamnosus (ATCC 334) are suggested as suitable strains in producing the fermented walnut flowers. The research findings could further support the development and utilization of walnut flowers as a fermented functional food. PRACTICAL APPLICATIONS: Walnut flowers have been used as fermented food in southwestern China, but their active components and functional activities during fermentation processes are still unclear. This study found that different probiotic fermentation exerted a strong and varied influence on the chemical composition and biological activities of the walnut flowers. A short-term fermentation has significantly improved their antioxidant capacities and α-glucosidase inhibitory abilities, whereas the longer period of fermentation, caused a significant loss of both their active compounds and bioactivities. These findings are useful as a reference for the manufacturers of fermented walnut flowers in selecting suitable strains and fermentation time for their products.

In Vitro Expanded Bioaccessibility of Quercetin-3-Rutinoside and Quercetin Aglycone from Buckwheat Biscuits Formulated from Flours Fermented by Lactic Acid Bacteria

The expanded bioaccessibility of rutin (Ru) and quercetin (Q) from buckwheat biscuits (BBs) formulated from liquid-state fermented flours by selected lactic acid bacteria (LAB) were determined after gastrointestinal digestion. Fermentation of buckwheat flours caused a LAB-dependent variation in Ru and Q content. BBs baked at 220 °C for 30 min showed lower content of Ru and Q, and no correlation was found between the content of these compounds in fermented flours and BBs. The expanded bioaccessibility of Ru from BBs was low when its content in the soluble and insoluble fractions remaining after digestion in vitro was taken into account. Contrary results were found for Q bioaccessibility which had an index greater than 1, indicating the high Q bioaccessibility from BBs. Since very low Q content was noted in the insoluble fraction remaining after BBs digestion, the high Q bioaccessibility was determined to be due to its concentration in the soluble fraction.

Biotransformation of Phlorizin by Eurotium cristatum to Increase the Antioxidant and Antibacterial Activity of Docynia indica Leaves

Docynia indica is used as a plant resource for both medicine and food in minority areas of southwestern China and Southeast of Asia, especially Docynia indica leaves, which are often used as a kind of functional tea in daily life. In our previous research, it has found that D. indica is rich in polyphenols (mainly phlorizin (PHZ)). Although PHZ is the first polyphenolic competitive inhibitor of sodium-dependent glucose transporters (SGLTs) to be discovered, the promotion and application of PHZ are limited due to its extremely low bioavailability. As a kind of aglycons, phloretin (PHT) possesses a better bioavailability and bioactivity than PHZ. Therefore, the conversion of PHZ to PHT in D. indica leaves by the method of biotransformation can be applied to solve the above issue. In this study, Aspergillus niger and Eurotium cristatum were used to transform PHZ to PHT in D. indica. Compared with Aspergillus niger, Eurotium cristatum can cause the equimolar conversion of PHZ to PHT. However, Aspergillus niger resulted in the complete degradation of PHZ. In the process of deep fermentation, PHZ in D. indica leaves was gradually biotransformed into PHT, and its content was as high as ~ 12% after fermentation. With the increase of PHT content, the antioxidant and antibacterial activity of Docynia indica leaves increased. By the acute toxicity evaluation, it was confirmed that Docynia indica leaves and Eurotium cristatum fermented leaves were much safer. These results indicate that Eurotium cristatum fermentation has the ability to transform the functional compounds in Docynia indica leaves and increase the antioxidant and antibacterial activity of Docynia indica, thus making it a substitute for PHT and functional tea.

Application of blockchain technology in food safety control：current trends and future prospects

Blockchain technology is a distributed ledger technology and is expected to face some difficulties and challenges in various industries due to its transparency, decentralization, tamper-proof nature, and encryption security. Food safety has been paid increasing attention in recent years with economic development. Based on a systematic literature critical analysis, the causes of food safety problems and the state-of-the-art blockchain technology overview, including the definition of blockchain, development history, classification, structure, characteristics, and main applications, the feasibility and application prospects of blockchain technology in plant food safety, animal food safety, and processed food safety were proposed in this review. Finally, the challenges of the blockchain technology itself and the difficulties in the application of food safety were analyzed. This study contributes to the extant literature in the field of food safety by discovering the excellent potential of blockchain technology and its implications for food safety control. Our results indicated that blockchain is a promising technology toward a food safety control, with many ongoing initiatives in food products, but many food-related issues, barriers, and challenges still exist. Nevertheless, it is expected to provide a feasible solution for controlling food safety risks.

Cicer arietinum L. Sprouts' Influence on Mineralization of Saos-2 and Migration of MCF-7 Cells

In the present study, we investigated the biological activity of four extracts obtained from Cicer arietinum L. sprouts. The fermentation of the sprouts with Lactobacillus casei and their incubation with β-glucosidase elevated the concentrations of isoflavonoids, especially coumestrol, formononetin and biochanin A. To study the biological activity of C. arietinum, the human osteosarcoma Saos-2 and human breast cancer MCF-7 cell lines were used. The extracts obtained from fermented sprouts exhibited the strongest ability to decrease intracellular oxidative stress in both types of cells. They augmented mineralization and alkaline phosphatase activity in Saos-2 cells, as well as diminished the secretion of interleukin-6 and tumor necrosis factor α. Simultaneously, the extracts, at the same doses, inhibited the migration of MCF-7 cells. On the other hand, elevated concentrations of C. arietinum induced apoptosis in estrogen-dependent MCF-7 cells, while lower doses stimulated cell proliferation. These results are important for carefully considering the use of fermented C. arietinum sprouts as a dietary supplement component for the prevention of osteoporosis.

The Effects of Trifolium pratense L. Sprouts' Phenolic Compounds on Cell Growth and Migration of MDA-MB-231, MCF-7 and HUVEC Cells

Uncontrolled growth and migration and invasion abilities are common for cancer cells in malignant tumors with low therapeutic effectiveness and high mortality and morbidity. Estrogen receptor β (ERβ), as a member of the nuclear receptor superfamily, shows potent tumor suppressive activities in many cancers. Phytoestrogens’ structural resemblance to 17 β-estradiol allows their binding to ERβ isoform predominantly, and therefore, expression of genes connected with elevated proliferation, motility and invasiveness of cancer cells may be downregulated. Among polyphenolic compounds with phytoestrogenic activity, there are isoflavones from Trifolium pratense L. (red clover) sprouts, containing high amounts of formononetin and biochanin A and their glycosides. To determine the source of the most biologically active isoflavones, we obtained four extracts from sprouts before and after their lactic fermentation and/or β-glucosidase treatment. Our previous results of ITC (isothermal titration calorimetry) modelling and a docking simulation showed clover isoflavones’ affinity to ERβ binding, which may downregulate cancer cell proliferation and migration. Thus, the biological activity of T. pratense sprouts’ extracts was checked under in vitro conditions against highly invasive human breast cancer cell line MDA-MB-231 and non-invasive human breast cancer cell line MCF-7 cells. To compare extracts’ activities acquired for cancer cells with those activities against normal cells, as a third model we choose human umbilical vein endothelial cells (HUVEC), which, due to their migration abilities, are involved in blood vessel formation. Extracts obtained from fermented sprouts at IC₀ dosages were able to inhibit migration of breast cancer cells through their influence on intracellular ROS generation; membrane stiffening; adhesion; regulation of MMP-9, N-cadherin and E-cadherin at transcriptional level; or VEGF secretion. Simultaneously, isolated phenolics revealed no toxicity against normal HUVEC cells. In the manuscript, we proposed a preliminary mechanism accounting for the in vitro activity of Trifolium pratense L. isoflavones. In this manner, T. pratense sprouts, especially after their lactic fermentation, can be considered a potent source of biological active phytoestrogens and a dietary supplement with anti-cancer and anti-invasion properties.

How Fermentation Affects the Antioxidant Properties of Cereals and Legumes

The major role of antioxidant compounds in preserving food shelf life, as well as providing health promoting benefits, combined with the increasing concern towards synthetic antioxidants, has led the scientific community to focus on natural antioxidants present in food matrices or resulting from microbial metabolism during fermentation. This review aims at providing a comprehensive overview of the effect of fermentation on the antioxidant compounds of vegetables, with emphasis on cereals- and legumes- derived foods. Polyphenols are the main natural antioxidants in food. However, they are often bound to cell wall, glycosylated, or in polymeric forms, which affect their bioaccessibility, yet several metabolic activities are involved in their release or conversion in more active forms. In some cases, the antioxidant properties in vitro, were also confirmed during in vivo studies. Similarly, bioactive peptides resulted from bacterial and fungal proteolysis, were also found to have ex vivo protective effect against oxidation. Fermentation also influenced the bioaccessibility of other compounds, such as vitamins and exopolysaccharides, enabling a further improvement of antioxidant activity in vitro and in vivo. The ability of fermentation to improve food antioxidant properties strictly relies on the metabolic activities of the starter used, and to further demonstrate its potential, more in vivo studies should be carried out.