Distribution of Vitamin B12, Thiamine, and Biotin in Marine Sediments

Vitamin B12, thiamine and biotin in the sediments collected from different 41 stations at the Eastern China Sea, the Pacific Ocean and the bays and inlet along the Pacific coast of Japan have been determined by microbiological assay methods using Lactobacillus leichmannii, Lactobacillus fermenti and Saccharomyces cerevisiae respectively. Vitamin B12 contents in the surface sediments were rather higher at such a shallow area as the Aburatsubo Inlet (1.14- 7.14m/!g/g) than those at other areas, the Japan Trench, the Mid-Pacific Ocean, the Eastern China Sea, the Suruga Bay and the Sagami Bay (0-2.10 m^g/g). Thiamine contents were similar levels in the sediments at all areas investigated (average of 0.31 /