Inactivation mechanisms of vitamin B12 by food additives and physiological effects of the inactivated vitamin

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K07736
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Food science
• Research Institution: Tottori University
• Principal Investigator: WATANABE Fumio 鳥取大学, 農学部, 教授 (30210941)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: ビタミンB12 / 食品添加物 / 次亜塩素酸 / ピロ亜硫酸ナトリウム / 亜硫酸ナトリウム

Outline of Final Research Achievements

Vitamin B12 (cyanocobalamin, CN-B12) was significantly changed by the treatment of hypochlorous acid water, sodium pyrosulfite and sodium sulfite. When CN-B12 was treated with these food additives in a test tube, hypochlorous acid water rapidly reacted with CN-B12, whose maximum absorptions at 361 nm and 550 nm were disappeared. On the other hand, no significant changes in absorption spectra of CN-B12 were observed for sodium pyrosulfite and sodium sulfite, but certain reaction product was detected and identified as sulfito-cobalmain by HPLC analysis. When effects of these food additives on B12 content of red shrimp were determined, no significant differences in B12 content was found by the treatment of these food additives. These results suggested that these food additives could not react food B12 because most of B12 in red shrimp meats existed as protein-bound form of B12, but not free form of B12.

Free Research Field

ビタミン学

Academic Significance and Societal Importance of the Research Achievements

我が国の指定食品添加物リストに記載されている449種からビタミンB12（B12）と反応性を高い添加物（次亜塩素酸水，ピロ亜硫酸ナトリウム，亜硫酸ナトリウム）を特定した．これら安全性の高い食品添加物であってもB12の構造を容易に変化させることが判明したことは学術的意義が大きい．しかし，実際の食品に含まれているB12はタンパク質に結合して存在するため，これら食品添加物の作用を受け難い結果となり，食品添加物が食品に含まれるB12の栄養価を低下させる可能性が低いことが示唆され，食品添加物の安全性を担保できたことは社会的意義が大きい．