2002 Fiscal Year Final Research Report Summary
Perfect prevention of oxidation of material with biological activity using regeneration reaction of lipid soluble antioxidant with catechin
Project/Area Number |
13450323
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
反応・分離工学
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Research Institution | Tohoku University |
Principal Investigator |
YONEMOTO Toshikuni Tohoku University, Graduate School of Engineering, Professor, 大学院・工学研究科, 教授 (40125688)
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Co-Investigator(Kenkyū-buntansha) |
KUBO Masaki Tohoku University, Graduate School of Engineering, Research Associate, 大学院・工学研究科, 助手 (50323069)
KITAKAWA Naomi Tohoku University, Graduate School of Engineering, Associate Professor, 大学院・工学研究科, 助教授 (00261503)
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Project Period (FY) |
2001 – 2002
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Keywords | biological activated material / antioxidant / prevention of oxidation / β-carotene / vitamin E / catechin |
Research Abstract |
The purpose of this research is to evaluate the antioxidant activity of catechin and to construct a novel method for preventing the oxidation of desired materials with biological activity in the actual food system using a regeneration reaction of lipid soluble antioxidant with catechin. In 2002, the oxidation experiments of β-carotene, an active oxygen quencher, were performed in an inert n-decane solvent with addition of epigallocatechin gallate (EGCG) or epicatechin gallate (ECG). In both cases, the induction period, in which the β-carotene concentration decreased slightly, was observed and the oxidation was suppressed. The induction period became longer with increasing the ECG concentration, whereas the period had a maximum at a certain EGCG concentration. EGCG containing pirogallol group is known to oxidize itself to produce activated oxygen. Therefore, EGCG was considered to have a progressive activity of the oxidation as well as the antioxidant activity. β-Carotene is commonly dis
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solved in the oil in water emulsion when used as a food additive. Catechin haying amphiphilic property is more easily dissolved in the water phase. The reaction of β-Carotene and lipid-soluble antioxidant, α-tocopherol, with catechin occurs on the oil-water interface. In 2003, the oxidation experiments in the presence of α-tocopherol were performed in the biphasic oil-water system having a definite interfacial area. In the biphasic system, the time for which α-tocopherol remained was longer than that in the single phase of n-decane. Since the β-carotene oxidation was suppressed during a-tocopherol remained in the oil phase, the existence of water phase was effective for the suppression of β-carotene oxidation. α-Tochopherol was consumed by its oxidation as well as the antioxidative protection of β-carotene. The peroxyl radical of α-tocopherol concerned with the chain oxidation was easy to dissolve in the water. This phenomenon seemed to contribute the restrain of α-tocopherol consumption, resulting in the suppression of β-carotene oxidation. A kinetic model was constructed by considering the transfer of the α-tocopherol peroxyl radical into the water phase in addition to the oxidation and antioxidation mechanisms of β-carotene. The model quantitatively described the oxidation behavior of β-carotene in the biphasic system over a wide range of the initial α-tocopherol concentrations. Less
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Research Products
(10 results)