IN VITRO MASS-SCREENING OF LACTIC ACID BACTERIA AS POTENTIAL BIOSORBENTS OF CESIUM AND STRONTIUM IONS

摘要

Many radionuclides were scattered by the explosion at the Fukushima Daiichi Nuclear Power Station. We examined whether lactic acid bacteria (LAB) can sorb cesium ions (Cs+) and strontium ions (Sr2+) for radioprotection. Many strains showed biosorption to Cs+ and Sr2+ using an in vitro mass-screening although each strain showed different sorption. We selected MYU 111, MYU 758, and MYU 759 strains that showed especially high biosorption to Cs+ and/or Sr2+. MYU 111 was identified as Lactobacillus plantarum, and MYU 758 and 759 were Pediococcus pentosaceus. The selected strains tended to show higher biosorption when using the buffer method compared to the culture method. Further, they showed high biosorption at a low concentration of 1 ppb Cs+ and Sr2+ (max 28.8% and 97.7% sorption, respectively). This is the first study where lactic acid bacteria are shown to have biosorption of Cs+ and Sr2+.