Pusztahelyi Tünde, Kovács Szilvia, Pócsi István, Prokisch József
Central Laboratory, Faculty of Agricultural and Food Sciences and Environmental Management, University of Debrecen, Böszörményi út 138, Debrecen H-4032, Hungary.
Central Laboratory, Faculty of Agricultural and Food Sciences and Environmental Management, University of Debrecen, Böszörményi út 138, Debrecen H-4032, Hungary.
J Trace Elem Med Biol. 2015 Apr;30:96-101. doi: 10.1016/j.jtemb.2014.11.003. Epub 2014 Nov 27.
Selenium deficiency is a major health problem worldwide for about 1 billion people. Bacterial cells usually possess low tolerance to selenite stress and also low ability to reduce high concentrations of toxic selenite. Here, high tolerance to selenite and selenium bioaccumulation capability were developed in mutated clones of probiotic and starter bacteria including Enterococcus faecium, Bifidobacterium animalis ssp. lactis, Lactobacillus casei and Lactococcus lactis ssp. lactis by food-level strain development process and clone selection. All mutant clones possessed increased glutathione concentration and glutathione reductase activity. The selenite treatment increased further these values in L. casei mutant strain pointing at a different selenite reduction pathway and/or stress response in this organism. Considerable conversion of selenite to cell bound selenium forms with a concomitant high biomass production was detected in E. faecium and B. animalis ssp. lactis cultures. Possible application of these strains as food and feed supplements is under investigation.
全球约有10亿人面临硒缺乏这一重大健康问题。细菌细胞通常对亚硒酸盐胁迫的耐受性较低，且还原高浓度有毒亚硒酸盐的能力也较弱。在此，通过食品级菌株开发过程和克隆筛选，在包括粪肠球菌、动物双歧杆菌乳亚种、干酪乳杆菌和乳酸乳球菌乳亚种在内的益生菌和发酵剂细菌的突变克隆中培育出了对亚硒酸盐的高耐受性和硒生物积累能力。所有突变克隆的谷胱甘肽浓度和谷胱甘肽还原酶活性均有所增加。亚硒酸盐处理进一步提高了干酪乳杆菌突变株中的这些值，表明该生物体中存在不同的亚硒酸盐还原途径和/或应激反应。在粪肠球菌和动物双歧杆菌乳亚种培养物中检测到亚硒酸盐大量转化为细胞结合硒形式，并伴随着高生物量产生。目前正在研究这些菌株作为食品和饲料补充剂的潜在应用。
