Abstract:Objective: To isolate and purify probiotic Lactobacillus from honey with high adsorption rate of heavy metal lead and edible. Methods: Physiological and biochemical experiments were performed on the isolated and purified strains, and a phylogenetic tree based on 16s rDNA was established for taxonomic identification; the probiotic properties of the strains were assessed by hemolysis, gelatinase activity, nitrate reduction and amino acid decarboxylase, self-aggregation and hydrophobicity, acid and bile salt resistance, and antimicrobial drug sensitivity. Meanwhile, inductively coupled plasma emission spectroscopy was used to determine the Pb2+ content in the solution before and after adsorption. The ability of the strains to adsorb heavy metals was explored. Scanning electron microscopy-X-ray energy spectroscopy was used to observe the adsorption of Pb2+ by the bacteria before and after adsorption. Fourier transform infrared spectroscopy was used to determine the adsorption of Pb2+ by the bacterium and the changes in protein structure. Results: Strain C10 screened from honey was identified as Lactobacillus plantarum, with no hemolytic and gelatinase activities; it could not reduce nitrate and did not decarboxylate to produce amines; self-aggregation and hydrophobicity reached 85.33% and 35.50%, respectively; survival under acid and bile salts was 39.39% and 98.79%, respectively; and it had strong sensitivity to chloramphenicol, erythromycin, ampicillin and cotrimoxazole. Lactobacillus plantarum C10 adsorbed 65.82% of heavy metals within 2 h. Scanning electron microscopy-X-ray spectroscopy showed that the percentage of lead element was 9.69%, and Fourier transform infrared spectroscopy showed that the secondary structure of the surface protein of the bacterium changed significantly after the adsorption of Pb2+. Conclusion: Lactobacillus plantarum C10 has good probiotic properties, can effectively adsorb Pb2+, and has the effect of preventing heavy metal poisoning.