| Selenium (Se) as a kind of trace element selenium has an important role inbiological effect and preventive treatment of disease, selenium biological activityscope is narrow, so it’s easy to show its toxicity. However, nano-Se has an advantageof good security and efficient. The high concentration of sodium selenite resistantingstrains was selected out from lactic acid bacteria which were preservated in thelaboratory. Then reduction product by sodium selenite was tested by TransmissionElectron Microscopy (TEM), X-ray Photoelectron Spectrometer (XPS) and Scanning andtunneling electron microscopy (SEM-EDX). The results showed that sodium selenitereduction to nanometer selenium by the high concentrations of sodium seleniteresistanting strains. Finally, the effects of nanometer selenium on biological in mice(antioxidant, growth and reproduction ability) were studied. The main results were asfollows:(1) The strain which with46.79%reduction rate (the concentration of sodiumselenite was4mM) was selected out from five higher reduction rate lactic acidbacteria strains. The reduction product was tested by XPS, TEM and SEM-EDX.The results showed that sodium selenite reduction to nanometer selenium with50-200nm particle size by LA4strain. Compared with common lactic acid bacteriastrains, more nano-se was restored by sodium selenite with LA4strain. So thereduction rate of LA4strain was higher than other lactic acid bacteria strains.(2) Sodium selenite was reduced to nano-Se by LA4strain which had hightolerance with sodium selenite. The nano-Se were given to Kunming mice by beinglavaged0,0.2,0.5and1.0mg/kg·bw nano-Se respectively. The effect of LA4lacticacid bacterially synthesized nano-Se on growth and reproduction performance ofmice was researched. The growth and reproduction performance of mice acceleratedobvious when0.5mg/kg nano-Se was added in. In this situation, the daily gain ofmice increased24.88%(P <0.01). The feed conversion ratio (F/G) decreased23.34%(P<0.01). The average farrowing rate increased40.00%. Compared with the control group, farrowing rate increased40.00%, meanwhile, the average offarrowing rate increased11.44%. Combined with that nano-Se could improve theactivity of glutathione peroxidase (GSH-Px) in whole blood and testis of mice to19.27%(P<0.01) and90.68%(P<0.01) respectively, and GSH-Px had an importantinfluence on reproduction performance of animal. It could conclude that LA4lacticacid bacterially synthesized Se（0）nanoparticles could improve the growth andreproduction performance in mice. According to the results of text, nano-Se couldalso accelerate the growth of mice when1.0mg/kg was added in（3）sodium selenite was reduced to nano-Se by LA4strain which had hightolerance with sodium selenite. The nano-Se were given to Kunming mice by gavage0,0.2,0.5and1.0mg/kg·bw nano-Se respectively. The effect of LA4lactic acidbacterially synthesized nano-Se on oxidation resistance of mice was researched. LA4lactic acid bacterially synthesized nano-Se could improve the activity of glutathioneperoxidase (GSH-Px) of whole blood and testis in mice (P<0.01) obviously, and alsoimprove total antioxidative capacity (T-AOC) and peroxidase (POD) of importantorgans, such as brain, liver, spleen and so on, in mice (P<0.01) obviously. Moreover,LA4lactic acid bacterially synthesized nano-Se could enhance the activity of totalsuperoxide dismutase (T-SOD) of serum in mice (P<0.01), it also could reduce thecontent of malondialdehyde (MDA) and MAO of serum and important organs inmice. In a conclusion, LA4lactic acid bacterially synthesized nano-Se couldimprove the oxidation resistance of mice, and the oxidation resistance of miceenhanced with the content of LA4lactic acid bacterially synthesized nano-Seincreasing. But when the content of LA4lactic acid bacterially synthesized nano-Seincreased to1.0mg/kg·bw, the oxidation resistance of mice improve not obvious. |
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