Characterization of vitamin B-12 compounds from edible shellfish, clam, oyster, and mussel

Vitamin B-12 content of various edible shellfish was determined by both Lac tobacillus leichmannii ATCC 7830 microbiological and intrinsic factor-chemi luminescence methods. The values determined by the microbiological method w ere 1.2-19.8 (M/C ratio) fold greater in the shellfish than the values dete rmined by the chemiluminescence method. Vitamin B-12 compounds were purifie d from most eaten shellfish, oyster (M/C, 1.5), mussel (M/C, 1.2), and shor t-necked clam (M/C, 2.7), and partially characterized. TLC and HPLC pattern s of each red-colored vitamin B-12 compound (M/C, 1.0-1.2) purified from th ese shellfish were identical to those of authentic vitamin B-12. Although t he higher values in the determination of vitamin B-12 by the microbiologica l method may be due to the occurrence of vitamin B-12-substitutive compound s, the edible shellfish would be excellent vitamin B-12 sources judging fro m the values (greater than or equal to 6 mug/100 g) determined by the chemi luminescence method.