Eco-Friendly Synthesis of Lactobacillus acidophilus-AgNPs: A Novel Approach to Combat Lipid Metabolism Disorders

Lactobacillus acidophilus, a well-known probiotic, has been extensively studied for its antioxidant, cholesterol-lowering, and anti-inflammatory properties. While silver nanoparticles (AgNPs) have various applications, the use of L. acidophilus biomass in AgNP synthesis, particularly in lipid metabolism requires careful evaluation.L. acidophilus-AgNPs was prepared, characterized and their lipid-lowering effects in high-fat diet (HFD)-induced obese mice. The isolated L. acidophilus was characterized using bile salt tolerance, cell-surface adherence, hemolytic testing, and 16S rDNA sequencing. We performed an MTC test to determine the most effective Ag+ concentration for biosynthesis, finding 2 mM to be optimal and harmless.L. acidophilus-AgNPs, exhibited a spherical morphology with an average particle size of 18.69 ± 0.57 nm and a PDI of 0.54. The zeta potential was -9.55 ± 0.8 mV. UV-visible and FTIR spectra revealed OH, C=O, NH, P-O, and P=O as main functional groups in the proteins and polysaccharides of L. acidophilus.L. acidophilus-AgNPs demonstrated notable lipid-lowering, antioxidant, and anti-inflammatory effects in HFD-induced obese mice. Administration of L. acidophilus-AgNPs increased plasma glucose, insulin, TG, TC, and HDL-C levels, and elevated FFA, GSH, SOD, GPx, GR, MDA, TNF-α, and MCP-1 concentrations. Histological studies corroborated these biochemical findings.In conclusion, L. acidophilus biomass can produce L. acidophilus-AgNPs, showcasing these bacteria as a natural microbial cell nanofactory. This method offers a sustainable and environmentally friendly approach to synthesizing L. acidophilus-AgNPs. The results suggest that L. acidophilus-AgNPs may be more effective in restoring antioxidant status in obese mice compared to metformin, rapidly counteracting lipid peroxidation and reducing obesity-related complications.