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Nutrition-gut cross-talk holds a vital position in sustaining intestinal function, and micronutrient metabolism has emerged as the foremost metabolic pathway to preserve gut homeostasis. Among micronutrients, B vitamins have evolved prior to DNA/RNA and are known for their vital roles for major evolutionary transitions in extant organisms. Despite their universal requirement and critical role, not all the three domains of life are endowed with a natural ability for de novo B vitamins synthesis. The human gut microbiome constitutes prototrophs and auxotroph which are entirely dependent on dietary intake and gut microbial production of B vitamins. The syntrophic metabolism involving cross-feeding of B vitamins and community-wide exchange between commensal bacteria elicit important changes in the diversity and composition of the human gut microbiome. Hereto, we discuss the B-vitamins sharing among prototrophic and auxotrophic gut bacteria, their absorption in small intestine and transport in distal gut, functional role in relation to the gut homeostasis and symptoms linked to their deficiency. We also briefly explore their potential involvement as psychobiotics in brain energetic metabolism (kynurenines/tryptophan pathway) for neurological functions and highlight their deficiency related malfunctioning. [ABSTRACT FROM AUTHOR]

Hard decision fusion algorithms have been widely used to improve the accuracy of cooperative spectrum sensing. However, the traditional hard decision fusion algorithms receive all sensing data without filtering, which provide an opportunity to malicious users. To defense malicious users' spectrum sensing data falsification (SSDF) attack, this paper proposes a double thresholds of reputation-based hard decision fusion algorithm (RHDF). In the RHDF algorithm, the fusion center merely receives sensing reports from trusted secondary users. Meanwhile, this algorithm can improve the efficiency of fusion decision by introducing the priority-half fusion method based on double thresholds and thus avoiding the impact of malicious users. The simulation results show that RHDF algorithm can more effectively defense SSDF attacks compared with traditional hard decision fusion algorithms and ensure better cooperation spectrum sensing performance. [ABSTRACT FROM AUTHOR]

Epidemiological evidence emphasizes that ariboflavinosis can lead to oxidative stress, which in turn may mediate the initiation and progression of liver injury and intestinal inflammation. Although vitamin B 2 has gained worldwide attention for its antioxidant defense, the relationship between B 2 status, oxidative stress, inflammatory response, and intestinal homeostasis remains indistinct. Herein, we developed a B 2 depletion-repletion BALB/c mice model to investigate the ameliorative effects of B 2 bioenriched fermented soymilk (B 2 FS) on ariboflavinosis, accompanied by oxidative stress, inflammation, and gut microbiota modulation in response to B 2 deficiency. In vivo results revealed that the phenotypic ariboflavinosis symptoms, growth rate, EGRAC status, and hepatic function reverted to normal after B 2 FS supplementation. B 2 FS significantly elevated CAT, SOD, T-AOC, and compromised MDA levels in the serum, simultaneously up-regulated Nrf2, CAT, and SOD2, and down-regulated Keap1 gene in the colon. The histopathological characteristics revealed significant alleviation in the liver and intestinal inflammation, confirmed by the downregulation of inflammatory (IL-1β and IL-6) and nuclear transcription (NF-κB) factors after B 2 FS supplementation. B 2 FS also increased the abundance and diversity of gut microbiota, increased the relative abundance of Prevotella and Absiella , as well as decreased Proteobacteria , Fusobacteria , Synergistetes , and Cyanobacteria in strong conjunction with antioxidant, anti-inflammatory properties, and gut homeostasis along with the remarkable increase in cecal SCFAs content. We hereby reveal that B 2 FS can effectively alleviate deleterious ariboflavinosis associated with oxidative stress mediated liver injury, chronic intestinal inflammation, and gut dysbiosis in the B 2 depletion-repletion mice model via activation of the Nrf2 signaling pathway.

Due to highly nutritious and well-known prebiotic nature, okara (soy by-product) can improve the physiological benefits of probiotic consumption by enhancing the physicochemical stability and bioavailability of bacteria and metabolites, partially in food matrices and then in gastrointestinal tract. Initially, vitamin B 2 producing probiotic Lactobacillus plantarum UFG10 was immobilized with 4% okara for soy milk fermentation. SEM micrographs showed firm adherence of UFG10 to okara surface depicting efficient immobilization. Soy milk fermented with okara immobilized UFG10 showed enhanced β-glucosidase activity, stimulating the biotransformation of isoflavones from glucosides (daidzin, from 27.78 to 9.84 μg/mL; genistin, from 32.58 to 8.33 μg/mL) to aglycones (daidzein, from 0.19 to 30.84 μg/mL; genistein, from 1.42 to 33.10 μg/mL) and higher B 2 production (1.53 μg/mL, 12 h) confirmed by HPLC. Okara addition and B 2 enrichment could yield relatively higher antioxidant strength than control soy milk. PLSR correlation revealed the effects of okara and B 2 on the functional properties of soy milk. After okara immobilization, soy milk showed higher soy protein digestibility after in vitro digestion for 225 min, higher aggregation, and lower protein molecular chains, qualitatively confirmed with Atomic force microscope. Okara immobilized bacterial cells exhibited relatively greater resistance up to 55.1% (p < 0.05) in simulated GIT, indicating okara as an ideal substrate for an efficient immobilization which ultimately improved the fate of soy B 2 and protein bioaccessibility and functional products such as isoflavones for micro structural design of soy milk with improved nutrition and digestibility., (Copyright © 2021 Elsevier Ltd. All rights reserved.)