Abstract
The night soil digestion plant in Tokyo is the largest one in Japan, where a thousand cubic meters of night soil is treated daily. The vitamin B_<12> content of centrifuged portion of the supernatant liquor from the plant was found to be much lower than that previously observed at the Kotoura plant, namely 9-17 μg/g on dry basis. Examinations were also made at the plants in Suwa and Kobe. The centrifuged portion of the supernatant liquor contained about 30 μg/g in the former and only about 10 μg/g in the latter.
