Vitamin B １２（or cobalamin） , an essential nutrient for humans, is unique because it is only synthesized by certain bacteria １） . In nature, vitamin B １２ synthesized by bacteria is taken up by plankton, which serve as a crucial food source for fish, shellfish, and other large aquatic organisms ２） . Vitamin B １２ becomes concentrated in the bodies of higher predators in the food chain, and it is eventually ingested by humans ３） . It is the only vitamin that is absent in plant-derived foods because plants cannot synthesize vitamin B １２ ４） . People who do not consume animal-derived foods, such as vegetarians, are at a high risk of developing vitamin B １２ deficiency, which has the major symptoms of neuropathy and megaloblastic anemia ３） . Therefore, the identification of plant-derived foods containing high levels of vitamin B １２ is necessary to prevent vegetarians from developing vitamin B １２ deficiency. Pickled vegetables, such as sauerkraut, are usually produced by spontaneous fermentation involving lactic acid bacteria ５） . Globally, sauerkraut is the most common cabbage-containing product and is commonly used in vegetarian dishes ６） . The vitamin B １２-synthesizing lactic acid bacteria Lactobacillus coryniformis and L. plantarum have been isolated from Japanese pickled vegetables ７） . Sauerkraut products containing considerable levels of vitamin B １２ could be excellent sources of vitamin B １２ for vegetarians. In the present study, we analyzed the vitamin B １２ content of four sauerkraut products consumed by European vegetarians. In addition, １６ strains of § Corresponding author, Determination of Vitamin B １２ Content of Sauerkraut（Pickled Cabbage）Products and Plant-Derived Lactic Acid Bacteria BITO Tomohiro ＊１ , FUJII Kumiko ＊１ , SHIMIZU Tomoko ＊１ , KITAMURA Yuko ＊１ , TANIOKA Yuri ＊２ , TAKENAKA Shigeo ＊３ , YABUTA Yukinori ＊１ , FURUSHO Tadasu ＊２ , AIMI Tadanori ＊１ , SCHWARZ Joachim ＊４ and WATANABE Fumio ＊１§ ＊１ Faculty of Agriculture, School of Agricultural, Life and Environmental Sciences, Tottori University, 4-101 Minami, Koyama-cho, Tottori, Tottori 680-8553 ＊２ Faculty of Applied Biological Science, Department of Nutritional Science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya, Tokyo 156-8502 ＊３ Graduate School of Comprehensive Rehabilitation, Osaka Prefecture University, 3-7-30 Habikino, Habikino, Osaka 598-8531 ＊４ Medical Practice Dr Med. Joachim Schwarz, Waldstrasse 44, 57520 Dickendorf, Germany Vitamin B １２ content of four types of commercially available sauerkraut （pickled cabbage） products was determined and characterized. Although one product contained considerable vitamin B １２ content （approximately ０ . ５ ㎍/１００gwetweight） , the remaining three products contained only traces of vitamin B １２. Subsequent liquid chromatography / electrospray ionization-tandem mass spectrometry analyses revealed that most of the corrinoids found in the high-vitamin B １２ sample was pseudo-vitamin B １２, an inactive corrinoid compound, thereby suggesting that this sauerkraut product is not a suitable source of vitamin B １２. Vitamin B １２ content in １６ Lactobacillus strains isolated from vegetables and fruits and their products was determined. Although all lactic acid bacteria grew well in vitamin B １２-deficient medium, only eight L. plantarum strains grew well in cabbage-extract medium, with L. plantarum FSCM ２-１２producing the highest biomass and vitamin B １２ content. （Received Apr.１８ ,２０１８; Accepted Aug.３０ ,２０１８） Key words：corrinoids, Lactobacillus plantarum, pickled cabbage, sauerkraut starter, vitamin B １２ コリノイド, ラクトバチラス プランタラム, キャベツの漬物, ザワークラウト, ビタミンB １２ Food Preservation Science VOL．４４ NO．６２０１８〔ResearchNote〕 （ 11 ） 293