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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+.

Heavy metals cause various health hazards. Using lactic acid bacteria (LAB), we tested the biosorption of heavy metals e.g. cadmium (Cd) (II), lead (Pb) (II), arsenic (As) (III), and mercury (Hg) (II). Cd (II) sorption was tested in 103 strains using atomic absorption spectrophotometery (AAS). Weissella viridescens MYU 205 (1 × 10(8) cells/ml) decreased Cd (II) levels in citrate buffer (pH 6.0) from one ppm to 0.459 ± 0.016 ppm, corresponding to 10.46 μg of Cd (II). After screening, 11 LAB strains were tested using various pH (pH 4.0, 5.0, 6.0, 7.0) showing the sorption was acid sensitive; and was cell concentration dependent, where the Cd (II) concentration decreased from one ppm to 0.042 (max)/0.255 (min) ppm at 1 × 10(10) cells/ml. Additionally, the biosorption of Pb (II), As (III), and Hg (II) were tested using an inductively coupled plasma mass spectrometer (ICP-MS). The Hg (II) concentration was reduced the most followed by Pb (II) and As (III). Many of the bacterial cell surface proteins of W. viridescens MYU 205 showed binding to Hg (II) using the Hg (II) column assay. Having a CXXC motif, a ∼14 kDa protein may be one of the Hg (II) binding proteins. LAB biosorption may aid the detoxification of people exposed to heavy metals.

飼料の制限が豚肉脂質および脂肪組織に及ぼす影響について検討した。ランドレース×大ヨークシャー×デュロック (LWD) 6頭を1区として, 飼料給与量別に不断給餌 (100%) 区, 不断給餌の80%制限および60%制限区の3区に分け, と殺24時間後に第12, 13胸椎に位置する胸最長筋 (ロース) を採取した。ロース, 皮下脂肪, 筋間脂肪の脂肪酸組成およびコレステロールの含量を測定した。ロース脂肪含量は3区ともほぼ同様の値を示し, 飼料給与量の違いによる影響は認められなかった。ロース全脂質脂肪酸では, 100%区から60%区にかけてパルミトオレイン酸とリノール酸は低下したが, 他の脂肪酸には差がなかった。ロース中性脂質脂肪酸組成では, 3区の脂肪酸はほぼ同様の値を示し影響はみられなかったが, ロース極性脂質では, ミリスチン酸, パルミチン酸, パルミトオレイン酸, リノール酸, 不飽和度に有意差 (P

The effects of several cooking methods (freeze-drying, roasting, boiling and frying) upon the persistence of diethylhexyl phthalate (DEHP) were investigated in eggs, liver and breast meat from laying hens which were given feed containing 1% phthalate for 4 weeks. The reduction rates of DEHP by cooking were 21.1-41.3% (freeze-drying), 26.1-52.5% (roasting), 11.6-33.1% (boiling) and 10.6-43.5% (frying). The rates of DEHP remaining in eggs, liver and meat were 56.5-82.1% 64.9-94.1% and 47.5-78.9%, respectively. The residual levels of DEHP in liver were the highest among the three samples after heating. After both freeze-drying and roasting ground meat for about 7 hours, the DEHP level reached equilibrium at about 1.5ppm.

The distribution of diethylhexyl phthalate (DEHP) administered to laying hens has been investigated. DEHP administered orally was detected in almost all organs and tissues of the laying hens. An especially high level of concentration was present in the adipose tissues and feathers. The shift of DEHP from skin to feather was suggested.