Degradation mechanism of lipids by the photo-oxidation and the development of application on anti-oxidation technology of lipids

采用鼓泡反应器研究了角鲨烯在不同条件下的氧化反应。对氧化过程中的氧化产物和分解产物进行了定性和定量分析。对于氧化，观察到两个阶段，即具有缓慢增加的过氧化氢的诱导期和具有快速增加的加速期。诱导期的氧化速率随光照强度的增加而增加，而加速期的氧化速率不受光照强度的影响。根据脂自由基的链式反应模型，导出了过氧化物的生成速率方程，并对实验结果进行了分析。过氧化物的形成速率与过氧化物浓度无关，并表示为诱导期内光强度的函数，并表示为加速期内过氧化物浓度的一阶。通过配备有化学发光和UV/维斯检测器的HPLC系统分析产生的过氧化物。角鲨烯氧化产物中检测到六种过氧化物。随着氧化的进行，过氧化物产物变成酮、醛、脂肪酸及其聚合物。

The oxidation reaction of squalene was investigated using a bubble column reactor under the various conditions either with or without UV irradiation. Oxidation products and decomposition products during the oxidation were also qualitatively and quantitatively analyzed. For the oxidation, two stages which are an induction period with a slow increase in hydroperoxide and an accelerated period with rapid increase are observed. The oxidation rate in the induction period increases with photo intensity, however, the rate in the accelerated period is unaffected by the UV irradiation. The formation rate equation of peroxide is derived from the chain reaction model of lipid radical and the experimental results are analyzed using the rate equation. The formation rate of the peroxide is independent on the peroxide concentration and expressed as a function of photo intensity in the induction period, and is expressed by the first order for the peroxide concentration in the accelerated period. The peroxide produced was analyzed by a HPLC system equipped with chemiluminescence and UV/VIS detectors. Six kinds of peroxide are detected as oxidation porducts from squalene. As the oxidation proceeds, the peroxide products are changed to ketones, aldehydes, fatty acids and their polymers.