酵母菌源纳米硒的制备、安全性评价及纳米硒奶片研发

Preparation,Safety Evaluation of Yeast-derived Nano-selenium and Its Milk Tablets Development

为降低无机砷毒性并提高硒的生物利用率,本文利用利用酵母菌将无机硒转化为纳米硒,通过对七株益生酵母菌的筛选,最终确定酿酒酵母ATCC 18824为最佳的硒转化菌株,并建立了其最佳纳米硒转化条件。利用场发射扫描电子显微镜(FE-SEM)、透射电子显微镜(TEM)及X射线光电子能谱(XPS)等技术对合成的纳米硒进行结构和形态的观察及特性表征,并通过小鼠30 d喂养实验验证了纳米硒的安全性。结果表明,ATCC18824合成的纳米硒表现出良好的分散性,呈现大小均一、饱满的圆球形的Se~0纳米硒单质,Na_(2)SeO_(3)添加量控制在0.5~1.5 mg/mL,30℃,60~72 h培养时为最优。研究还发现,纳米硒在胞内合成,随时间延长逐渐释放胞外,可在72 h完全排出胞外。30 d喂养实验表明纳米硒对小鼠体重变化、脏器指数、血液常规和生化分析、主要脏器组织等均无显著性影响,验证了其体内安全性。基于此,本研究成功研发了感官评价良好、营养成分丰富的酵母菌源纳米硒奶片,硒含量为12.67μg/g、16.67μg/g和33.33μg/g,营养价值高于部分市售奶片,展示了其在食品加工业中作为新型安全食品添加剂的潜在应用价值。

In order to reduce the toxicity of inorganic arsenic and improve the bioavailability of selenium,this study used yeast to convert inorganic selenium into synthesize selenium nanoparticles(SeNPs).Through the screening of seven probiotic yeast strains,Saccharomyces cerevisiae ATCC 18824 was finally screened as the best nano-selenium synthesized strain and its optimal nano-selenium synthesized conditions were established.The synthesized nano-selenium was observed and characterized in terms of structure and morphology using field emission scanning electron microscopy(FE-SEM),transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS).In addition,the safety of nano-selenium was verified by feeding experiments in mice for 30 days.ATCC 18824 synthesized nano-selenium exhibited good dispersion,presenting Se0 nano selenium monoliths of uniform size and full spherical shape,and the Na_(2)SeO_(3) addition was controlled to be optimal at 0.5~1.5 mg/mL,30℃,and 60~72 h incubation.It was also found that nano-selenium was synthesized intracellularly and gradually released over time,ultimately excreted within 72 hours.The 30 days feeding experiment showed that nano-selenium had no significant effect on body weight change,organ index,blood routine and biochemical analysis,and major organ tissues in mice,verifying the safety of nano-selenium.Based on the results of the study,the present study successfully developed yeast-derived nano-selenium milk tablets with good sensory evaluation and rich nutritional content of 12.67μg/g,16.67μg/g,and 33.33μg/g of selenium,its nutritional value was higher than part of the commercially available milk tablets,showing its potential as a novel and safe food additive in the food processing industry application value in the food processing industry.