Kinetic modelling of the degradation of the alpha-tocopherol in biodiesel-rape methyl ester.

The aim of this work was to study the influence of three major factors (light, atmospheric oxygen, temperature) responsible for the degradation of tocopherols. The evolution of alpha-tocopherol contents was analysed by high-performance liquid chromatography. Taguchi's experimental design was applied to establish a mathematical model of alpha-tocopherols degradation in function of the studied parameters especially in a domain of temperature between 50 degrees C and 150 degrees C.

In vitro reaction of the carcinogenic derivative N-acetoxy-7-ethyl-N-2-acetylaminofluorene with DNA. A spectroscopic study.

In vitro reaction of DNA with N-acetoxy-7-ethyl-N-acetylaminofluorene (N-AcO-EtAAF is compared to that with N-acetoxy-N-acetyl-2-aminofluorene. Introduction of an ethyl group at the position 7 of the fluorene ring is found to induce an increase of reactivity of this (model) metabolite of carcinogen N-acetoxy-2-aminofluorene (2-AAF) toward DNA and its constituents. Spectroscopic methods (u.