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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.

Adhesion tests are complex, time-consuming and expensive, while the most important criterion for a probiotic lactobacilli is the ability to adhere to the human intestine. Thirty lactobacilli isolates from human intestinal tissues were measured for cell surface glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity using a microtiter plate screening method. GAPDH activities were detected in 21 out of 30 samples from 12 h cultures and in all samples from 18 h cultures. This suggests GAPDH is universally expressed on the bacterial cell surfaces from many lactobacilli. A statistically significant positive correlation was shown between GAPDH activity and adhesion using the BIACORE adhesion assay (P < 0.01). The new screening method using GAPDH enzymatic activity without an adhesion test may be possible due to the significant positive correlation of GAPDH activity with adhesion of lactobacilli derived from the human intestine.

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.

Sept phases stationnaires sont utilisees: DEGS, SE-30, OV-17, SE-52, QF-1, PEG-20M et Apiezon M

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.