The present study investigated the iron-binding ability of exopolysaccharides (EPS) producing lactic acid bacteria (LAB) as a whole-cell in comparison with its extracted crude EPS. A total of eight EPS producing LAB strains and four iron salts were tested for in-situ iron complex formation in whey as a basal culture medium. Among the four iron salts, ferrous sulphate showed maximum complexation with all the LAB strains. Amongst eight EPS producing LAB strains, Lacticaseibacillus rhamnosus Kar1 showed significantly higher (P < 0.05) iron complexing ability in comparison with the other strains. In-situ iron chelating ability of EPS producing L. rhamnosus Kar1 strain was notably higher (65.5 ± 0.62%) than the ex-situ approach in whey (51.62 ± 0.89%) but was considerably lower than that observed in an aqueous medium (75.29 ± 0.824%). Under optimized conditions, L. rhamnosus Kar1 showed 81.20 ± 0.38% iron complex formation in whey supplemented with 11% glucose and 20 ppm iron (ferrous sulphate) at the fermentation duration of 14 h. These findings suggest that L. rhamnosus Kar1 and its EPS can be further explored to develop iron-fortified whey-based products upon amalgamation with suitable technology.
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