Tsuyoshi Tsuduki, Associate professor of Tohoku University, Received Mishima Kaiun Scientific Awards in 2014
The writer: Tsuyoshi TSUDUKI
Research field: Food and Biomolecular Science, Nutritional Biochemistry
The title of this prize is "Food and nutritional characteristics of fatty acids with conjugated double bonds". The content of this prize is outlined as follows.
In this study, the physiological effect of fatty acids with conjugated double bond was widely examined in vitro and in vivo. The determination method of conjugated fatty acids in food and biological samples was established first. That is, the sodium methoxide/methanol (NaOCH3/MeOH) method and the tetramethylguanidine/methanol (TMG/MeOH) method were most efficient in preventing the artificial isomerization of conjugated fatty acids and for avoiding the artificial generation of unknown byproducts. Next, it was clarified that the oxidative stability of conjugated fatty acids improves by the form of triacylglycerol and by adding the antioxidant (vitamin E). And, the influence on the lipid metabolism and the pharmacokinetics of conjugated fatty acids were clarified in vivo. That is, α-eleostearic acid (9cis, 11trans, 13trans - 18:3) is converted to conjugated linoleic acid (9cis, 11trans - 18:2) by a Δ13-saturation reaction carried out by an NADPH-dependent enzyme. In addition, the anti-tumor effect, the anti-angiogenesis effect, and the anti-obesity effect of conjugated fatty acids were newly found. That is, it was shown that; conjugated fatty acids had a strong suppressive effect on tumor growth through induction of apoptosis via lipid peroxidation; conjugated fatty acids are PPARγ ligands, activates PPARγ, induce apoptosis in vascular endothelial cells, and inhibits angiogenesis; intake of conjugated fatty acid appears to suppress the accumulation of fat in the liver and adipose tissue, and improves lipid and sugar metabolism. Therefore, the profitability of conjugated fatty acids was shown. These findings suggest that conjugated fatty acid has potential use as a dietary supplement and medicine for health maintenance.