VITAMIN B₁₂ IN MARINE AND FRESHWATER ALGAE

Abstract

Asakusanori, the air-dried Porphyra tenera, used as a foodstuff in Japan, was found to be relatively rich in vitamin B₁₂ and to possess a growth-promoting activity on the young chicks fed an all plant protein ration. Over thirty species of other seaweeds were tested and the vitamin contents were found to vary from 0.1 to 4.0γ/100g on a fresh basis. Several zoo-and phytoplanktons and bottom muds of pond were also analysed and proved to be very rich in this vitamin. The author's view on the significance of the vitamin in algae is proposed, especially on the utility of marine and freshwater algae as APF sources.