著者
Fumio WATANABE Shigeo TAKENAKA Hiromi KITTAKA-KATSURA Shuhei EBARA Emi MIYAMOTO
出版者
Center for Academic Publications Japan
雑誌
Journal of Nutritional Science and Vitaminology (ISSN:03014800)
巻号頁・発行日
vol.48, no.5, pp.325-331, 2002 (Released:2009-04-28)
参考文献数
35
被引用文献数
43 90 76

Substantial amounts of vitamin B12 were found in some edible algae (green and purple layers) and algal health food (chlorella and spirulina tablets) using the Lactobacillus delbrueckii subsp. lactis ATCC7830 microbiological assay method. Corrinoidcompounds were purified and characterized from these algae to clarify the chemical properties and bioavailability of the algal vitamin B12. True vitamin B12 is the predominate cobamide of green and purple layers and chlorella tablets. Feeding the purple layer to vitamin B12-deficient rats significantly improved the vitamin B12 status. The results suggest that algal vitamin B12 is a bioavailable source for mammals. Pseudovitamin B12 (an inactive corrinoid) predominated in the spirulina tablets, which are not suitable for use as a vitamin B12 source, especially for vegetarians.
著者
Fumio WATANABE Shigeo TAKENAKA Hiromi KATSURA Emi MIYAMOTO Katsuo ABE Yoshiyuki TAMURA Toshiyuki NAKATSUKA Yoshihisa NAKANO
出版者
(社)日本農芸化学会
雑誌
Bioscience, Biotechnology, and Biochemistry (ISSN:09168451)
巻号頁・発行日
vol.64, no.12, pp.2712-2715, 2000 (Released:2005-01-28)
参考文献数
12
被引用文献数
34

The edible purple laver, Porphyra yezoensis, contained 51.49±1.51 μg of vitamin B12 compounds per 100 g dry weight of the laver (mean±SEM, n=4). A vitamin B12 compound was purified from the lyophilized purple laver and partially characterized. The silica gel 60 TLC and reversed-phase HPLC patterns of the purified pink-colored compound were identical to those of authentic vitamin B12, but not to those of vitamin B12 analogues inactive for humans.
著者
Fumio WATANABE Joachi SCHWARZ Shigeo TAKENAKA Emi MIYAMOTO Noriharu OHISHI Esther NELLE Rahel HOCHSTRASSER Yukinori YABUTA
出版者
Center for Academic Publications Japan
雑誌
Journal of Nutritional Science and Vitaminology (ISSN:03014800)
巻号頁・発行日
vol.58, no.6, pp.438-441, 2012 (Released:2013-02-19)
参考文献数
9
被引用文献数
9 28

This study determined the vitamin B12 content of six wild edible mushrooms which are consumed by European vegetarians. Zero or trace levels (0.01-0.09 μg/100 g dry weight) of vitamin B12 were determined in porcini mushrooms (Boletus spp.), parasol mushrooms (Macrolepiota procera), oyster mushrooms (Pleurotus ostreatus), and black morels (Morchella conica). By contrast, black trumpet (Craterellus cornucopioides) and golden chanterelle (Cantharellus cibarius) mushrooms contained considerable levels (1.09-2.65 μg/100 g dry weight) of vitamin B12. To determine whether C. cornucopioides or C. cibarius contained vitamin B12 or other corrinoid compounds that are inactive in humans, we purified a corrinoid compound using an immunoaffinity column and identified it as vitamin B12 based on LC/ESI-MS/MS chromatograms.
著者
Fumio WATANABE Yuri TANIOKA Emi MIYAMOTO Tomoyuki FUJITA Hiroyuki TAKENAKA Yoshihisa NAKANO
出版者
Center for Academic Publications Japan
雑誌
Journal of Nutritional Science and Vitaminology (ISSN:03014800)
巻号頁・発行日
vol.53, no.2, pp.183-186, 2007 (Released:2008-01-10)
参考文献数
19
被引用文献数
15 19

Vitamin B12 content (98.8±5.6 μg/100 g dry weight) of an edible cyanobacterium, Nostoc commune (Ishikurage) was determined by the Lactobacillus delbrueckii ATCC 7830 microbiological method. Bioautography with vitamin B12-dependent Escherichia coli 215 indicated that N. commune contained two (main and minor) corrinoid-compounds. These corrinoid-compounds were purified to homogeneity from the dried algal cells and characterized. The main and minor purified corrinoid-compounds were identified as pseudovitamin B12 and vitamin B12, respectively, on the basis of silica gel 60 TLC, C18 reversed-phase HPLC, 1H NMR spectroscopy, and UV-visible spectroscopy. These results suggest that the bacterial cells are not suitable for use as a vitamin B12 source, especially in vegetarians.
著者
Hiromi KITTAKA-KATSURA Fumio WATANABE Yoshihisa NAKANO
出版者
Center for Academic Publications Japan
雑誌
Journal of Nutritional Science and Vitaminology (ISSN:03014800)
巻号頁・発行日
vol.50, no.6, pp.438-440, 2004 (Released:2009-04-28)
参考文献数
7
被引用文献数
8 11

Vitamin B12 contents of green (0046-0263 and 0, 125-0535μg/ 100g dry weight), blue (0.068-0.081 and 0.525-0.528μg/100g dry weight), red (0.061 and 0.663μg/100g dry weight), and black (0.104-0.859 and 0.305-1.20μg/100g dry weight) tea leaves were obtained by intrinsic factor-chemiluminescence and microbiological methods, respectively. Although vitamin Bit was found in all tea leaves tested by both assay methods, the higher values by the microbiological method were not due to occurrence of both deoxyribosides and deoxynucleotides (known as an alkali-resistant factor), but may have been due to that of inactive corrinoid compounds for mammals in the tea leaves.