Application of Partial Hydrogenation for the Generation of Minor Tocochromanol Homologs and Functional Evaluation of Hydrogenated Tocotrienol-rich Vitamin E Oil in Diabetic Obese Mice

Recent research has identified minor homologs of vitamin E with one or two double bonds in the side-chain, namely tocomonoenol (Ti) and tocodienol (T2), in natural products. We first explored the effectiveness of partial hydrogenation for generating minor tocochromanols from tocotrienol (T3). During hydrogenation with pure alpha-T3 as a substrate, the side-chain was partially saturated in a time-dependent manner, and a large amount of alpha-T1 and alpha-T2 was obtained. To investigate the beneficial effects of the hydrogenated product, we fed diabetic obese KK-A(y) mice with a hydrogenated T3 mixture (HT3). Feeding HT3 revealed tissue-specific accumulation of tocochromanols, ameliorated hyperglycemia and improved ratio of high-density lipoprotein cholesterol to total cholesterol in serum, with invariant bode weight and fat mass. Hence, we propose that hydrogenation is a useful method for generating T1 and T2 homologs, which can be applied to explore the structure-related function of tocochromanols.