Exploring the phytochemical composition and pharmacological effects of fermented turmeric using the isolated strain Lactobacillus rhamnosus FN7

Turmeric (Curcuma longa), widely used in Asia as a spice, preservative, and colorant, contains curcuminoids known for diverse pharmacological benefits, including antimicrobial properties. However, their hydrophobic nature hampers bioavailability. Addressing this, we hypothesized that Lactic Acid Bacteria (LAB) fermentation could enhance curcuminoid content and bioactivity. This study isolated LAB strains to ferment turmeric and investigated the phytochemical and pharmacological outcomes. Twelve LAB strains from various sources were tested for fermenting 3% turmeric in MRS broth. L. rhamnosus FN7 emerged as a robust strain, tolerating turmeric′s antibacterial properties and increasing curcuminoid content and anti-inflammatory effects. Fermented turmeric exhibited higher phenolic and flavonoid contents and improved radical scavenging activity than its non-fermented counterpart. Additionally, L. rhamnosus FN7 survived under simulated gastrointestinal conditions, indicating probiotic potential. Our findings suggest that L. rhamnosus FN7 fermentation significantly boosts turmeric′s biochemical attributes, positioning it as a promising functional food.