Bioactive Isoflavones Research Articles

Production of equol, dehydroequol, 5-hydroxy-equol and 5-hydroxy-dehydroequol in soy beverages by the action of dihydrodaidzein reductase in Limosilactobacillus fermentum strains

Equol and 5-hydroxy-equol, and their analogous compounds dehydroequol and 5-hydroxy-dehydroequol, are bioactive isoflavones formed by microbial metabolism. The aims of this work were to elucidate the formation of dehydroequol and 5-hydroxy-dehydroequol, to identify the role of dihydrodaidzein reductase (DHDR) in the production of equol, dehydroequol, 5-hydroxy-equol and 5-hydroxy-dehydroequol and to develop soy beverages enriched in these compounds through engineered lactic acid bacteria. DHDR was responsible for the production of equol and dehydroequol from dihydrodaidzein (DHD), and of 5-hydroxy-equol and 5-hydroxy-dehydroequol from dihydrogenistein (DHG), even in the absence of tetrahydrodaidzein reductase (THDR). The combination of DHDR with dihydrodaidzein racemase (DDRC), and/or THDR, allowed the production of soy beverages enriched in equol (241.34 ± 34.56 μM), dehydroequol (31.23 ± 5.78 μM), 5-hydroxy-equol (125.54 ± 7.90 μM) and 5-hydroxy-dehydroequol (292.34 ± 14.67 μM). Beverages fortified with high concentrations of equol, 5-hydroxy-dehydroequol and 5-hydroxy-equol could provide significant health benefits for consumers.

Formononetin ameliorates dextran sulfate sodium-induced colitis via enhancing antioxidant capacity, promoting tight junction protein expression and reshaping M1/M2 macrophage polarization balance

Ulcerative colitis (UC) is a complex, refractory inflammatory bowel disease characterized impared intestinal mucosal barrier and imbalanced M1/M2 macrophage polarization mediating its progression. Formononetin (FN), a bioactive isoflavone with established anti-inflammatory and immunomodulatory properties, shows promise in mitigating UC, yet its therapeutic and underlying mechanisms remain unclear. In this study, colitis was induced in mice by administering 2.5% (w/v) dextran sulfate sodium (DSS) solution for 7 days. Oral (25, 50, and 100 mg/kg) FN for 10 days significantly ameliorated colitis symptoms in a dose-dependent manner, by mitigating body weight loss, reducing disease activity index (DAI), colonic weight, and colonic weight index, while enhancing survival rates and colonic length. Histological analysis revealed FN remarkably suppressed inflammatory damage in colonic tissues. Furthermore, FN modulated the expression of pro- and anti-inflammatory cytokines and enhanced antioxidant capacity. Notably, FN treatment significantly enhanced the expression of tight junction (TJ) proteins (claudin-1, ZO-1, occludin) at both protein and mRNA levels in the colon tissues, suggesting improved intestinal barrier function. Crucially, FN inhibited macrophage infiltration in colonic tissues and rebalanced M1/M2 macrophage polarization. While, macrophage depletion largely abrogated FN’s protective effects against colitis, indicating a crucial role for macrophages in mediating FN’s therapeutic response. Overall, FN effectively alleviated colitis primarily via modulating inflammatory cytokine expression, enhancing antioxidant capacity, upregulating TJs proteins expression, and remodeling M1/M2 macrophage polarization equilibrium. These findings suggest that FN could be the next candidate to unlocking UC’s treatment challenge.

Isoflavones and lysozyme interplay: Molecular insights into binding mechanisms and inhibitory efficacies of isoflavones against protein modification

In this study, we investigated the complexation of bioactive isoflavones, specifically biochanin A (BCA) and genistein (GEN), with hen egg white lysozyme (HEWL) and explored their inhibitory effects on HEWL modification using a combination of multi-spectroscopic and computational methods. The observed binding affinity was of a moderate nature (on the order of 104 M−1), and a static quenching mechanism was identified in the fluorescence quenching process. Notably, the binding constant (Kb) for GEN (4.449 ± 0.262 × 104 M−1) was found to be higher than that for BCA (3.707 ± 0.108 × 104 M−1) towards HEWL. Our spectroscopic measurements, complemented by molecular docking calculations, suggested the involvement of Trp62 in the binding site of the isoflavones within the geometry of HEWL. The micro-environment surrounding the Trp-residues exhibited an increase in hydrophilicity, as indicated by Synchronous fluorescence (SFS) and three-dimensional fluorescence (3D) studies. Interestingly, circular dichroism (CD) studies revealed no marked alteration in the secondary structure of HEWL upon binding with the isoflavones. Furthermore, our investigation into the interaction patterns, employing FTIR and molecular docking studies, revealed a predominance of hydrogen bonding and hydrophobic interactions. Beyond the binding study, the isoflavones demonstrated a promising inhibitory effect on the d-ribose-mediated glycation of HEWL, as well as on HEWL fibrillation, as evidenced by fluorescence emission studies. Our findings not only exhibited an excellent correlation with experimental observations but also provided precise insights into the location and dynamics of isoflavones within the binding site through detailed analyses of molecular docking and molecular dynamics simulation data.

Puerarin Modulates Hepatic Farnesoid X Receptor and Gut Microbiota in High-Fat Diet-Induced Obese Mice.

Obesity is associated with alterations in lipid metabolism and gut microbiota dysbiosis. This study investigated the effects of puerarin, a bioactive isoflavone, on lipid metabolism disorders and gut microbiota in high-fat diet (HFD)-induced obese mice. Supplementation with puerarin reduced plasma alanine aminotransferase, liver triglyceride, liver free fatty acid (FFA), and improved gut microbiota dysbiosis in obese mice. Puerarin's beneficial metabolic effects were attenuated when farnesoid X receptor (FXR) was antagonized, suggesting FXR-mediated mechanisms. In hepatocytes, puerarin ameliorated high FFA-induced sterol regulatory element-binding protein (SREBP) 1 signaling, inflammation, and mitochondrial dysfunction in an FXR-dependent manner. In obese mice, puerarin reduced liver damage, regulated hepatic lipogenesis, decreased inflammation, improved mitochondrial function, and modulated mitophagy and ubiquitin-proteasome pathways, but was less effective in FXR knockout mice. Puerarin upregulated hepatic expression of FXR, bile salt export pump (BSEP), and downregulated cytochrome P450 7A1 (CYP7A1) and sodium taurocholate transporter (NTCP), indicating modulation of bile acid synthesis and transport. Puerarin also restored gut microbial diversity, the Firmicutes/Bacteroidetes ratio, and the abundance of Clostridium celatum and Akkermansia muciniphila. This study demonstrates that puerarin effectively ameliorates metabolic disturbances and gut microbiota dysbiosis in obese mice, predominantly through FXR-dependent pathways. These findings underscore puerarin's potential as a therapeutic agent for managing obesity and enhancing gut health, highlighting its dual role in improving metabolic functions and modulating microbial communities.

Puerarin-A Promising Flavonoid: Biosynthesis, Extraction Methods, Analytical Techniques, and Biological Effects.

Flavonoids, a variety of plant secondary metabolites, are known for their diverse biological activities. Isoflavones are a subgroup of flavonoids that have gained attention for their potential health benefits. Puerarin is one of the bioactive isoflavones found in the Kudzu root and Pueraria genus, which is widely used in alternative Chinese medicine, and has been found to be effective in treating chronic conditions like cardiovascular diseases, liver diseases, gastric diseases, respiratory diseases, diabetes, Alzheimer's disease, and cancer. Puerarin has been extensively researched and used in both scientific and clinical studies over the past few years. The purpose of this review is to provide an up-to-date exploration of puerarin biosynthesis, the most common extraction methods, analytical techniques, and biological effects, which have the potential to provide a new perspective for medical and pharmaceutical research and development.

In vitro simulated saliva, gastric, and intestinal digestion followed by faecal fermentation reveals a potential modulatory activity of Epimedium on human gut microbiota

Herba Epimedii, known for its rich array of bioactive ingredients and widespread use in ethnopharmacological practices, still lacks a comprehensive understanding of its gastrointestinal biotransformation. In this study, we qualitatively explored the dynamic changes in Epimedium sagittatum components during in vitro simulated digestions, with a quantitative focus on its five major flavonoids. Notably, significant metabolism of E. sagittatum constituents occurred in the simulated small intestinal fluid and colonic fermentation stages, yielding various low molecular weight metabolites. Flavonoids like kaempferol glycosides were fully metabolized in the simulated intestinal fluid, while hyperoside digestion occurred during simulated colon digestion. Colonic fermentation led to the production of two known bioactive isoflavones, genistein, and daidzein. The content and bioaccessibility of the five major epimedium flavonoids—icariin, epimedin A, epimedin B, epimedin C, and baohuoside I—significantly increased after intestinal digestion. During colon fermentation, these components gradually decreased but remained incompletely metabolized after 72 h. Faecal samples after E. sagittatum fermentation exhibited shift towards dominance by Lactobacillus (Firmicutes), Bifidobacterium (Actinobacteria), Streptococcus (Firmicutes), and Dialister (Firmicutes). These findings enhance our comprehension of diverse stages of Herba Epimedii constituents in the gut, suggesting that the primary constituents become bioaccessible in the colon, where new bioactive compounds may emerge.

93 Red clover as a functional feed: Effects on rumen microbiota of finishing ram lambs

Abstract Red clover (RC) contains bioactive isoflavones. Supplementing RC as a functional feed (as little as 7.5% of the total diet) has been shown to alter ruminal fermentation and improve feed efficiency in ram lambs fed high-concentrate finishing diets. The objectives of this study were to determine if reduced RC inclusion will produce similar rumen microbiological effects. It was hypothesized that RC supplementation below 7.5% RC will alter rumen microbial community composition during the finishing period. Sixteen individually housed Polypay ram lambs (age; 134 ± 2.5 d; initial body weight: 31 ± 0.53 kg) were used in a complete block design and fed one of four isocaloric and isonitrogenous diets (85:15 concentrate:roughage ratio; n = 4 rams diet1): a control diet in which the roughage component (15.0% wt/wt of total diet) consisted of orchardgrass hay, 2.5%-RC (roughage: 2.5% RC; 12.5% orchardgrass wt/wt), 5.0%-RC (roughage: 5.0% RC; 10% orchardgrass wt/wt), and 7.5%-RC (roughage: 7.5% RC; 7.5% orchardgrass wt/wt). Rumen fluid was collected via oral intubation at 0, 2, 4, 6, and 8 h post-feeding at the end of the adaptation period (14 d; all rams on control diet) and at 21-d intervals during the trial. Rumen functional bacterial guilds, including hyper-ammonia-producing bacteria (HAB), amylolytic, lactate-utilizing (LU), and cellulolytic bacteria were enumerated via serial dilution at 4 h post-feeding. Data were analyzed using PROC MIXED with repeated measures in SAS (v.9.4, SAS inst. Inc., Cary, NC). There were no differences between diets on d 0 for any variable (P > 0.05). At d 21, all RC-containing diets exhibited a 10- to 100-fold reduction in ruminal HAB compared with the control (P < 0.05). While suppression of HAB was no longer apparent by d 42 in 2.5%-RC, HAB had decreased 100-fold (109 to 107) in lambs fed the 5.0%-RC and 7.5%-RC diets (P < 0.01). No differences in amylolytic bacteria were detected on d 21 (P > 0.05), but were 10-fold less in all diets containing RC by d 42 in comparison with control (109 to 108; P = 0.08). In contrast, LU increased by d 21 and were 100-fold greater (106 to 108) by d 42 when compared with the control for all levels of RC supplementation (P < 0.05). Cellulolytic bacteria also increased across the study period in all lambs fed RC diets, with 100-fold greater cellulolytics (106 to 108) by d 42 (P < 0.05). Consistent with the hypothesis, supplementing RC at levels as low as 2.5% wt/wt of the total diet decreased protein-wasting HAB and amylolytic bacteria while coincidingly increasing LU and cellulolytic bacteria in the rumen. These results indicate that adding red clover to finishing diets has the potential to increase lamb growth and feed efficiency through a functional feed action.

Characterization and stabilization of GluLm and its application to deglycosylate dietary flavonoids and lignans

This study describes the characterization of the recombinant GH3 aryl-β-glucosidase “GluLm” from Limosilactobacillus mucosae INIA P508, followed by its immobilization on an agarose support with the aim of developing an efficient application to increase the availability and concentration of flavonoid and lignan aglycones in a vegetal beverage. In previous studies, heterologous GluLm-producing strains demonstrated a great capacity to deglycosylate flavonoids. Nevertheless, the physicochemical properties and substrate spectrum of the enzyme remained unknown up to now. A high production of purified GluLm was achieved (14 mg L−1). GluLm exhibited optimal activity at broad ranges of pH (5.0–8.0) and temperature (25–60°C), as well as high affinity (Km of 0.10 mmol L−1) and specific constant (86554.0 mmol L−1 s−1) against p-nitrophenyl-β-D-glucopyranoside. Similar to other GH3 β-glucosidases described in lactic acid bacteria, GluLm exhibited β-xylosidase, β-galactosidase, and β-fucosidase activities. However, this study has revealed for the first time that a GH3 β-glucosidase is capable to hydrolyze different families of glycosylated phenolics such as flavonoids and secoiridoids. Although it exhibited low thermal stability, immobilization of GluLm improved its thermostability and allowed the development of a beverage based on soybeans and flaxseed extract with high concentration of bioactive isoflavone (daidzein, genistein), lignan (secoisolariciresinol, pinoresinol, and matairesinol), and other flavonoid aglycones.Key points• Limosilactobacillus mucosae INIA P508 GluLm was purified and biochemically characterized• Immobilized GluLm efficiently deglycosylated flavonoids and lignans from a vegetal beverage• A viable application to produce vegetal beverages with a high content of aglycones is described

Formononetin ameliorates airway inflammation by suppressing ESR1/NLRP3/Caspase-1 signaling in asthma

Since inhaled glucocorticoids are the first-line treatment for asthma, asthma management becomes extremely difficult when asthma does not react well to glucocorticoids. Formononetin, a bioactive isoflavone and typical phytoestrogen, has been shown to have an anti-inflammatory impact while alleviating epithelial barrier dysfunction, which plays a role in the pathogenesis of allergic illnesses like asthma. However, the biological mechanisms behind this impact are unknown. As a result, we set out to investigate the effects of formononetin on airway inflammation and epithelial barrier repair in house dust mite (HDM)-induced asthmatic mice. We further expanded on formononetin's putative mode of action in reducing airway inflammation by modifying epithelial barrier dysfunction. In the current study, researchers discovered that formononetin significantly lowered total IgE levels in serum and interleukin (IL)-4, IL-6, and IL-17A levels in bronchoalveolar lavage fluid (BALF) in HDM-challenged asthmatic mice. Experiments on cell proliferation, migration, and apoptosis were performed in vitro to determine the effect of formononetin on bronchial epithelial barrier repair. Furthermore, in lipopolysaccharide (LPS)-stimulated 16HBE cells, formononetin increased cell proliferation and migration while preventing apoptosis and lowering the Bax/Bcl-2 ratio. In vitro and in vivo, formononetin significantly inhibited toll-like receptor 4 (TLR4) and estrogen receptor (ESR1)/Nod-like receptor family pyrin domain-containing protein 3 (NLRP3)/Caspase-1 signaling. These findings show that formononetin can reduce airway inflammation in HDM-challenged asthmatic mice by promoting epithelial barrier repair and possibly by inhibiting ESR1/NLRP3/Caspase-1 signaling as the underlying mechanism; formononetin could be a promising alternative treatment for asthma.

Fermented soy beverages as vehicle of probiotic lactobacilli strains and source of bioactive isoflavones: A potential double functional effect

Soy beverages can be a source of bioactive isoflavones, with potential human health benefits. In this work, the suitability of three Lacticaseibacillus and three Bifidobacterium probiotic strains as functional starters for soy beverage fermentation were evaluated, alongside with the effect of refrigerated storage on the viability of the strains and the isoflavone composition of the fermented beverages. The three bifidobacteria strains suffered a decrease in their viability during refrigeration and only Bifidobacterium breve INIA P734 produced high concentrations of bioactive isoflavones. Meanwhile, L. rhamnosus GG and L. rhamnosus INIA P344 produced high levels of aglycones and, with L. paracasei INIA P272, maintained their viability during the refrigeration period, constituting promising starters to obtain functional soy beverages that could gather the benefits of the bioactive isoflavone aglycones and the probiotic strains. Moreover, the three lactobacilli caused an increase in the antioxidant capacity of the fermented beverages, which was maintained over the refrigerated storage.

A new biopotentially active isoflavone glycoside from the stem of Ficus arnottiana Miq.

A new bioactive isoflavone glycoside with a molecular formula C<sub>34</sub>H<sub>42</sub>O<sub>20</sub>, melting point 261°C-263°C and [M]<sup>+</sup> 770 was isolated from the methanol soluble fraction of 90% methanolic extract of the stem of <em>Ficus arnottiana </em>Miq. The compound was illustrated as a new bioactive isoflavone glycoside 5,6,5ˈ-trihydroxy-8,3ˈ-dimethoxy-isoflavone 5ˈ-O-α-L-rhamnopyranosyl (1→3) O-α-L xylopyranosyl 5-O-β-D-glucopyranoside were characterized with the help of various chemical reactions, Fourier transforms infrared spectroscopy (FT-IR), Nuclear magnetic resonance spectroscopy (1HNMR), Mass spectrometry (LC-MS) and chemical degradations. Isolated compounds were also used for the antimicrobial activity of micro-organisms worked successfully tested against all strains: <em>Escherichia coli, Bacillus cereus, and Staphylococcus aureus, </em>while the least activity by<em> Pseudomonas aeruginosa</em>.

Isoflavone Metabolism by Lactic Acid Bacteria and Its Application in the Development of Fermented Soy Food with Beneficial Effects on Human Health.

Isoflavones are phenolic compounds (considered as phytoestrogens) with estrogenic and antioxidant function, which are highly beneficial for human health, especially in the aged population. However, isoflavones in foods are not bioavailable and, therefore, have low biological activity. Additionally, their transformation into bioactive compounds by microorganisms is necessary to obtain bioavailable isoflavones with beneficial effects on human health. Many lactic acid bacteria (LAB) can transform the methylated and glycosylated forms of isoflavones naturally present in foods into more bioavailable aglycones, such as daidzein, genistein and glycitein. In addition, certain LAB strains are capable of transforming isoflavone aglycones into compounds with a greater biological activity, such as dihydrodaidzein (DHD), O-desmethylangolensin (O-DMA), dihydrogenistein (DHG) and 6-hydroxy-O-desmethylangolensin (6-OH-O-DMA). Moreover, Lactococcus garviae 20-92 is able to produce equol. Another strategy in the bioconversion of isoflavones is the heterologous expression of genes from Slackia isoflavoniconvertens DSM22006, which have allowed the production of DHD, DHG, equol and 5-hydroxy-equol in high concentrations by engineered LAB strains. Accordingly, the consequences of isoflavone metabolism by LAB and its application in the development of foods enriched in bioactive isoflavones, as well as health benefits attributed to their consumption, will be addressed in this work.

Sustainable production of genistin from glycerol by constructing and optimizing Escherichia coli

Genistin is one of the bioactive isoflavone glucosides found in legumes, which have great nutraceutical and pharmaceutical significance. The market available isoflavones are currently produced by direct plant extraction. However, its low abundance in plant and structural complexity hinders access to this phytopharmaceutical via plant extraction or chemical synthesis. Here, the E. coli cell factory for sustainable production of genistin from glycerol was constructed. First, we rebuilt the precursor genistein biosynthesis pathway in E. coli, and its titer was then increased by 668% by identifying rate-limiting steps and applying an artificial protein scaffold system. Then de novo production of genistin from glycerol was achieved by functional screening and introduction of glycosyl-transferases, UDP-glucose pathway and specific genistin efflux pumps, and 48.1 mg/L of genistin was obtained. A further engineered E. coli strain equipped with an improved malonyl-CoA pathway, alternative glycerol-utilization pathways, acetyl-CoA carboxylase (ACC), and CRISPR interference (CRISPRi) mediated regulation produced up to 137.8 mg/L of genistin in shake flask cultures. Finally, 202.7 mg/L genistin was achieved through fed-batch fermentation in a 3-L bioreactor. This study represents the de novo genistin production from glycerol for the first time and will lay the foundation for low-cost microbial production of glucoside isoflavones. In addition, the multiphase workflow may provide a reference for engineering the biosynthetic pathways in other microbial hosts as well, for green manufacturing of complex natural products.

Soy Milk as Pertinent Functional Food: Potential Benefits & Health Concerns

Background: Soy products, such as soy milk, which is generally regarded as a viable nutritive and medicinal vegan food source globally, can be attributed with promoting human health. Cow milk and soy milk have comparable protein (between 7 and 12 g), fat (between 2.5 and 6 g), omega-3 fatty acids, peptides, and trypsin inhibitors. Certain issues with the usage of cow milk, such as allergenicity, lactose intolerance, the presence of cholesterol, and veganism, have increased global demand for vegan diets, with worries about health and the environment playing a big role. Purpose & Scope: In vivo and in vitro investigations on soy milk have shown the mechanisms of bioactive isoflavones (genistein, daidzein, glycitein, saponins, phytates, and phytosterols). Soy acts as a balanced and therapeutic alternative in the fight against cancer prevention by preventing the disintegration of the extracellular matrix that encircles developing arteries and tumors, the reduction of blood insulin and cholesterol levels by maintaining glucose and lipid metabolism, the relief of menopausal syndromes, and effects of osteo-protection by modifying receptors, thus functioning as a safer transition to hormonal reversal. Summary and conclusion; More research on the therapeutic properties of soy milk as a functional food can be conducted. This review aims to provide a comprehensive overview of the multiple health benefits, the current status of several conceivable soy milk products, and the possibility for additional research in other disciplines. An attempt was made to research the good and negative effects of isoflavones and bioactive compounds derived from soy. Factors to consider include administration, dosage, metabolism, the presence of endogenous estrogen, and toxicity studies

Isolation of Mirificin and Other Bioactive Isoflavone Glycosides from the Kudzu Root Lyophilisate Using Centrifugal Partition and Flash Chromatographic Techniques.

Pueraria lobata (Willd.) Ohwi is a legume taxon native to Southeast Asia and widely used in traditional medicine systems of that region. The therapeutic applications of the underground parts of this species (known as kudzu root) are related to its high content of isoflavones, mainly the characteristic C-glycoside derivatives. Within this group, the most explored compound both phytochemically and pharmacologically is puerarin. However, current scientific findings document important anti-biodegenerative effects for some of the minor isoflavones from kudzu roots. Therefore, the main objective of the study was to develop an original preparative method that allowed the efficient isolation of closely related hydrophilic daidzein C-glycosides, including mirificin, from vacuum-dried aqueous-ethanolic extracts of kudzu roots. For this purpose, the combined centrifugal partition (CPC) and flash chromatographic (FC) techniques were elaborated and used. The optimized biphasic solvent system in CPC, with ethyl acetate, ethanol, water, and 0.5% (V/V) acetic acid as a mobile phase modifier, enabled the purification and separation of the polar fraction containing bioactive isoflavones and ultimately the isolation of mirificin, 3′-hydroxy- and 3′-methoxypuerarin, puerarin, and daidzin using FC. The identity of isoflavones was confirmed using spectroscopic (UV absorption and nuclear magnetic resonance) and mass spectrometric methods. The determined purity of isolated mirificin was 63%.

Studies on the Isolation and Molecular Mechanisms of Bioactive Phytochemicals

Studies on the isolation and molecular mechanisms of phytochemicals with anti-tumor or anti-inflammatory properties are important to developing new drugs for cancer and neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. In the course of a study to screen bioactive isoflavones from Erythrina poeppigiana (Leguminosae), we isolated an isoflavone with potent apoptosis-inducing activity against human leukemia HL-60 cells. It was designated erypoegin K. The studies demonstrated an enantiomer, (S)-erypoegin K, displayed selective cytotoxic activity, was a novel inhibitor of topoisomerase II, and possessed anti-tumor activity both in vitro and in vivo. We identified other apoptosis-inducing isoflavones with the ability to inhibit glyoxalase I. Dimeric acridone alkaloids, carbazole alkaloids, and coumarin and quinoline derivatives-all obtained mainly from plants in the family Rutaceae-induced apoptosis of HL-60 cells via the production of reactive oxygen species and mitochondrial dysfunction. We also identified terpenoid coumarins, carbazole quinones, rotenoid derivatives, and quinolone alkaloids with anti-inflammatory activities. These compounds reduced nitric oxide (NO) production from RAW264.7 macrophage cells stimulated with lipopolysaccharides and interferon-γ. Some of the compounds displayed neuroprotective activity by reducing NO production. This review primarily describes our recent studies on erypoegin K, and other compounds with apoptosis-inducing and anti-inflammatory activities.

Behavior study of Bifidobacterium longum using solid state fermentation from commercial soybean meal

The development of alternatives to dairy products has gained great importance using plant-based foods. In this study, efforts have been made to develop vegetable alternatives from soybean paste without any supplement using single potential probiotic culture. Commercial soybean meal was inoculated with Bifidobacterium (B.) longum under previously fitted fermentation conditions by experimental design. Carbohydrates, organic acids, isoflavones, and amino acids profiles were studied in nine conditions of moisture and temperature, and also at several times in optimized conditions. Kinetics and technological parameters, effect of simulated gastric conditions on bacterium survival in optimized soybean paste, and their relationship with soybean matrix using scanning electron microscopy (SEM) were also evaluated. B. longum was able to use the main carbohydrates in soybean producing organic acids as was expected (acetic/lactic ∼ 1.5) and to enhance bioactive isoflavones (maximum concentration: 32.6 mg/50 g of soybean paste). Furthermore, B. longum showed high tolerance at simulated saliva solution and gastric juice, but the pancreatic solution deeply affected its viability in MRSs and also in soybean paste. Soybean paste represents an excellent vegetable candidate to be used as potential probiotic carrier food for B. longum and an attractive alternative to develop new functional foods.

Formononetin regulates endothelial nitric oxide synthase to protect vascular endothelium in deep vein thrombosis rats.

ObjectiveFormononetin is a bioactive isoflavone that has numerous medicinal benefits. We explored the feasibility and its mechanism of formononetin on treating acute deep vein thrombosis (DVT) in rats.Materials and methodsInferior vena cava (IVC) stenosis was performed to establish the DVT rat model. First, different doses of formononetin were used to observe the feasibility of formononetin on treating DVT. In sham and DVT groups, rats were orally treated with vehicle. In the remaining groups, formononetin (10 mg/kg, 20 mg/kg, and 40 mg/kg) was orally treated once a day for 7 days at 24 h after IVC. After 7 days, the levels of thrombosis and inflammation related factors in plasma were measured. The expression of endothelial nitric oxide synthase (eNOS) was analyzed by western blot and immunofluorescence. Molecular docking was used to evaluate the interaction between the formononetin and eNOS. Further, the NOS inhibitor (L-NAME) was used to explore the mechanism of formononetin for DVT.ResultAfter treatment with formononetin, the average weights of thrombosis were decreased, and the levels of thrombosis and inflammation related factors were also significantly decreased. Additionally, phosphorylation of eNOS was increased with the formononetin administration. There is a good activity of formononetin to eNOS (total score = −6.8). However, the effects of 40 mg/kg formononetin were concealed by the NOS inhibitor (L-NAME).ConclusionFormononetin reduces vascular endothelium injury induced by DVT through increasing eNOS in rats, which provides a potential drug for treatment of venous thrombosis.

Effect of storage and heat treatment on the levels of bioactive flavonoids produced in fermented soy beverages

Among vegetable functional products, soy-based foods stand out for their high content in protein and flavonoids, mainly isoflavones. The fermentation of soy beverages with selected bacterial strains is a way to obtain a product enriched in isoflavone aglycones, alongside with other isoflavone derivates and other bioactive flavonoids. Two bacterial strains with high activity on the transformation of these compounds, Limosilactobacillus mucosae INIA P508 and Bifidobacterium pseudocatenulatum INIA P815, were tested for the fermentation of soy beverage. Both strains produced high concentration of the aglycones daidzein and genistein, in addition to a significant increase (P < 0.01) of glycitein, O-desmethylangolensin, 6″-hydroxy-O-desmethylangolensin, tetrahydrodaidzein and other flavonoid aglycones such as kaempferol, naringenin and luteolin. Two alternatives to conserve the developed functional beverages were explored, cold storage and thermal treatment. Refrigeration did not affect the concentration of isoflavones, even observing an increase in aglycones. Similarly, the thermal treatment and further room temperature storage did not reduce the amounts of daidzein and genistein. Therefore, both strains could be used for the development of soy beverages enriched in bioactive isoflavones and other bioactive flavonoids which would maintain their concentrations in refrigeration or at room temperature after heat treatment.

Effects of enzyme-assisted extraction on the profile and bioaccessibility of isoflavones from soybean flour

The effects of enzymatic extraction strategies on extractability, bioconversion, and bioaccessibility of biologically active isoflavone aglycones, total phenolic content, and antioxidant activity of aqueous extracts from full-fat soy flour were evaluated. Protease, tannase, and cellulase enzymes were used individually or in combination. Except for the protease treatment, all enzymatic treatments increased the extraction of biologically active isoflavones (daidzein and genistein) compared with the control. The use of a mixture of protease, tannase, and cellulase resulted in increased extractability and/or bioconversion of aglycones from soy flour, indicating a synergistic effect amongst the enzymes. Daidzein and genistein concentrations increased from 29.0 to 158.2 μg/g and from 27.0 to 156.5 μg/g (compared to the control), respectively. Furthermore, enzymatic extraction followed by in vitro gastrointestinal digestion significantly increased the bioaccessibility of isoflavone aglycones, total phenolic content (by 22–45%), and antioxidant activity (by 15–22%) of the extracts. These results demonstrate that enzyme selection is an efficient strategy to maximize the extraction, bioconversion, and bioaccessibility of bioactive isoflavones from soy flour, which could contribute to health benefits associated with the consumption of soy-rich products.