Bioremoval of lead (pb) salts from synbiotic milk by lactic acid bacteria

The present study investigated the effects of five species of indigenous probiotic bacteria (Lactobacillus sp. and Bifidobacterium sp.) and prebiotic inulin on the decontamination of two Pb²⁺ salts (lead nitrate and lead acetate) in food models (low-fat, semi-fat, and high-fat milk). The average of the lowest and highest pH values was related to samples containing L. paracasei and L. acidophilus bacteria, as determined by pH change results. In most instances, adding inulin accelerated the pH-decreasing process, but the results were not particularly significant (p < 0.05). All probiotic strains were able to remove both forms of Pb salts, however, lead nitrate mitigation was significantly higher (p < 0.05). According to decontamination analysis, B. lactis was a native probiotic species with a high capacity for the absorption and biological elimination of Pb salts from milk medium (in low-, semi-, and high-fat milk, 94.41, 98.13, and 98.12% respectively). Except for low-fat milk, samples containing inulin showed greater Pb removal in semi-fat and high-fat milk than those without inulin. The findings of FTIR-ATR spectroscopy revealed that hydroxyl (OH), carbonyl (C = O), carboxylic (-COOH), phosphate (P = O), amine (-NH₂), and amide (-C(= O) = N) functional groups are efficient in the absorption of Pb salts through electrostatic interactions on the cell surfaces of probiotics. The findings of this research highlighted the importance of using probiotic strains specific to the B. lactis BIA-6 species for those who are at risk of being exposed to Pb salts and other toxic components through diet.