Riboflavin production by lactic acid bacteria: a mini-review

Riboflavin (RF) or vitamin B₂ is an essential micronutrient for redox balance, energy metabolism, and cellular homeostasis. Although RF production titers of lactic acid bacteria (LAB) are lower than those achieved by established industrial microorganisms such as Ashbya gossypii and Bacillus subtilis, LAB are a promising and attractive platform for the development of functional foods and nutraceuticals enriched with RF because they have a generally regarded as safe/qualified presumption of safety status, probiotic potential, natural association with numerous consumed fermented foods, and compatibility with food-grade commercial processes. It has been demonstrated that several RF-producing LAB possess stable phenotypes, survive gastrointestinal conditions, exhibit antimicrobial activity against human pathogens, and display favorable adhesion to intestinal epithelial cells and antibiotic susceptibility profiles. Their industrial feasibility is further strengthened by advances in strategies to enhance their RF biosynthetic capacity, fermentation optimization, and microencapsulation technologies, which improve LAB strain performance, product safety and stability, and RF delivery. Collectively, LAB represent a sustainable, consumer-friendly, and regulatory-compliant solution for enhancing the RF content in foods and beverages and meeting the growing demand for clean-label functional products. This review summarizes the regulatory mechanisms underlying RF biosynthesis, recent advances in RF production, and progress in the development of LAB-based RF-enriched foods.