Investigation On The Interaction Of Vitamin A With The Peroxide

Vitamin A is involved in many physiological activities to maintain human health, playing an important role in human growth and development. However, vitamin A deficiency is a widespread public health problem in our residents. Vitamin A fortified products supplement is an effective way to prevent vitamin A deficiency. It is a general phenomenon that the peroxides cause destruction of Vitamin A by direct interaction in preparation. For a long time, the degradation products were not clearly known. In this paper, liquid chromatography (HPLC), infrared spectroscopy (IR) and gel permeation chromatography (GPC), etc. technologies were used to analyze the process of vitamin A degradation by peroxides. The results suggested polymerization is the main way of degradation. Since excessive dose may cause toxication, the concentration of vitamin A is often low in the final products. The kinetics of vitamin A degradation is of great importance to the storage period. We studied the apparent kinetics of degradation in low concentration by UV absorption spectra. It was confirmed that the degradation process obeys first order kinetics. Higher temperature accelerated the rate of degradation. The degradation rate constants were3.60x10-2h-1,7.52×10-2h-1and14.0×10-2h-1at60℃,70℃and80℃, respectively. The apparent activation energy was66.4kJ.mol"1. In addition, density functional theory (DFT) method was utilized to calculate the isomers characteristics and simulate electron transition spectra. The reactivity of different isomers with peroxides was discussed based on the molecular orbital theory.