抄録
For the purpose of simplification and improvements, investigations were made on the static culture method for the microbiological determination of vitamin B_<12> with Ochromonas malhamensis specific for antipernicious anemia factor. It was confirmed that satisfactory vitamin B_<12> values could be obtained by means of the static culture procedure of Ochromonas malhamensis. An attempt made to enlarge assay range of the dose-response curve of Ochromonas malhamensis showed that surface active agents other than Tween 80 such as Tween 40,60 as well as Myri 52 were effective for improving the growth of the organism, but the effect was not so remarkable as to enable the attainment of the purpose.
