Studies on Euglena and vitamin B12.

Abstract

Hutner et al (1949) reported that Euglena gracilis var. bacillaris exhibits a quantitative growth response to crystalline antipernicious anemia factor (vitamin B12) This discovery makes it possible to use Euglena as a means of bioassay for this factor. The following presents some results on vitamin B12 as determined from the growth of Euglena gracilis. Materials. The culture of Euglena gracilis var. bacillaris employed was kindly supplied by Dr. S. H. Hutner. Three media were used. The composition of Medium I and Medium II we owe to the courtesy of Dr. Hutner and Dr. T. H. Jukes. Medium I (acid) and II (neutral) were used for the cultivation of Euglena. Medium III was devised for the detection of organisms which synthesize B12. Medium I, in addition to mineral salts, contained thiamine, glutamic acid and malic acid. Its pH was adjusted to 3.0. It was prepared by mixing suitable amounts of three stock solutions.