Asian Ferments: Microbiota, Metabolic, Lipid, Inflammatory, Barrier, And Bile-Acid Pathways

Aim — This review synthesizes open-access evidence on Asian fermented foods, particularly Indonesian varieties, containing lactic acid bacteria (LAB) and Bacillus probiotics. Six health domains were considered: gut microbiota modulation, glucose metabolism, lipid regulation, bile-acid/energy signalling, anti-inflammatory activity, and gut-barrier integrity. Mechanistic pathways were mapped, notably SCFA→FFAR2/3→AMPK and BSH-mediated bile-acid remodelling→FXR/TGR5→GLP-1/energy, linking microbial activity to clinical outcomes. Methods — Systematic searches (2013-2025) were performed in PMC, ScienceDirect, Semantic Scholar, BioMed Central, PLOS, and MDPI for studies on tempeh, natto, kimchi, miso/doenjang, bekasam/peda, tempoyak, and isolated strains. Results — Evidence converged across domains: (1) gut microbiota shifted toward LAB/Bifidobacterium and SCFA producers; (2) modest glycaemic improvements (HbA1c, FBG, HOMA-IR) via SCFA-AMPK pathways; (3) lipid reductions (TC, LDL-C, TG) associated with BSH-driven bile-acid remodelling and FXR/TGR5-GLP-1 activity; (4) lower inflammation (CRP, cytokines) through <ns0:sc>NF-kB/MAPK </ns0:sc>suppression; (5) strengthened gut-barrier integrity (increased ZO-1/occludin/claudins). High-value microbe-food anchors included Lactiplantibacillus plantarum (kimchi/tempeh), Bacillus subtilis (natto), and Pediococcus spp. (bekasam/peda). Conclusion — Asian fermented foods provide culturally congruent dietary platforms that modestly improve glycaemia, lipid profiles, inflammation, and barrier health. Future priorities are head-to-head randomized trials of Southeast Asian ferments, strain-resolved reporting, matrix-aware dosing/duration, and shared biomarker endpoints.