Cobamide Fingerprinting Reveals Nutritional Diversity of Vitamin B12 in Edible Shellfish

In edible shellfish, vitamin B12 content has traditionally been evaluated based on total content; however, recent studies reveal substantial diversity in corrinoid composition among species. This review integrates molecular and ecological perspectives to reassess vitamin B12 levels in shellfish using cobamide fingerprinting. Filter-feeding bivalves generally exhibit vitamin B12-dominant profiles, whereas herbivorous gastropods often contain higher proportions of pseudovitamin B12, and carnivorous species display intermediate or vitamin B12-dominant patterns reflecting trophic transfer. In addition, physicochemical form and food processing influence vitamin B12 bioavailability. These findings collectively demonstrate that a precise nutritional assessment requires a comprehensive evaluation of both the total content and the molecular makeup of corrinoids.