Biosynthesis of tellurium nanoparticles by Lactobacillus plantarum and the effect of nanoparticle-enriched probiotics on the lipid profiles of mice.

Hypercholesterolemia is an important risk factor contributing to atherosclerosis and coronary heart disease. Lactic acid bacteria have attracted much attention regarding their promising effect on serum cholesterol levels. Tellurium (Te) is a rare element that has also gained considerable interest for its biological effects. There have been some recent in vivo reports on the reduction effect of Te on cholesterol content. In this study, Lactobacillus plantarum PTCC 1058 was employed for the intracellular biosynthesis of Te NPs. The UV-visible spectrum of purified NPs showed a peak at 214 nm related to the surface plasmon resonance of the Te NPs. Transmission electron microscopy showed that spherical nanoparticles without aggregation had the average size of 45.7 nm as determined by the laser scattering method. The energy dispersive X-ray pattern confirmed the presence of Te atoms without any impurities. A significant reduction was observed in group which received L. plantarum with or without Te NPs during propylthiouracil and cholesterol diet in compare with the control group which received just propylthiouracil and cholesterol. The levels of triglycerides also remarkably decrease (p<0.05) in mice given L. plantarum with intracellular Te NPs.