Biological Activity of Hydroxo-vitamin B12 Degradation Product Formed during Microwave Heating

• Published in: Journal of agricultural and food chemistry 1998-12, Vol.46 (12), p.5177-5180
• Main Authors: Watanabe, Fumio, Abe, Katsuo, Katsura, Hiromi, Takenaka, Shigeo, Mazumder, S. A. M. Zakir Hussain, Yamaji, Ryoichi, Ebara, Syuhei, Fujita, Tomoyuki, Tanimori, Shinji, Kirihata, Mitsunori, Nakano, Yoshihisa
• Format: Article
• Language: English
• Subjects: activity; Biological and medical sciences; characterization; degradation; Food industries; Fundamental and applied biological sciences. Psychology; General aspects; hydroxocobalamin; microwave cooking; Miscellaneous; purification; toxicity
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf980727v

When hydroxo-vitamin B12, which predominates in foods, is treated by microwave heating, two degradation products with R f of 0.16 and 0.27 are found and characterized (Watanabe et al. J. Agric. Food Chem. 1998, 46, 206−210). A novel hydroxo-vitamin B12 degradation product with a R f of 0.12 was also found by the use of silica gel 60 column chromatography and was the major compound among the degradation products. The degradation product with a R f of 0.12 was purified to homogeneity and partially characterized. The purified degradation product had about 13% and 23% biological activity of authentic vitamin B12 in hog intrinsic factor (a mammalian vitamin B12-binding protein) and Lactobacillus leichmannii ATCC 7830, respectively. Administration of the purified degradation product (0.5 μg/week) to rats indicates that the compound does not have significant activity in mammals. Keywords: Vitamin B12; degradation; microwave heating; intrinsic factor; Lactobacillus leichmannii; mammalian cells; rat