Identification of vitamin B12 and pseudovitamin B12 from various edible shellfish using liquid chromatography–electrospray ionization/tandem mass spectrometry

Abstract

In this study, the vitamin B12 contents were analyzed in the edible portions of various shellfish (bivalves and snails). High vitamin B12 contents (30.5–53.3 μg/100 g wet weight) were detected in mussels, surf clams, bloody clams, and freshwater clams. However, scallops and abalone had extremely low vitamin B12 contents (0.1–1.1 μg/100 g wet weight) which was attributed to only the muscle portions being edible. These results suggest that high levels of vitamin B12 are accumulated in the viscera of shellfish. Vitamin B12 levels were also significantly higher in bivalves than in snails. The corrinoid compounds purified from all bivalves were identified as “true” vitamin B12 using liquid chromatography–electrospray ionization/tandem mass spectrometry. In edible snails, abalone, and pond snails, however, both vitamin B12 and pseudovitamin B12 (an inactive corrinoid) were observed to be the major and minor corrinoid compounds, respectively. Based on these results, we conclude that the whole bodies of these edible bivalves are excellent sources of vitamin B12 for humans.