THE CULTURE OF EUDIPLODINIUM NEGLECTUM, WITH EXPERIMENTS ON THE DIGESTION OF CELLULOSE

¹ Department of Zoology and Physiology, University of Texas, Austin

A successful method for culturing a cattle ciliate, Eudiplodinium neglectum, has been developed. A medium containing grass and celullose in addition to inorganic salts has supported continuous culture for a period of 22 months. The osmotic pressure of the medium must be suitable and oxygen must be excluded. The protozoa are obligate anaerobes.

The protozoa have been grown in sufficient numbers to permit preparation of an enzyme extract which is shown to be active in cellulose digestion. The optimum acidity for action of the cellulase is about pH 5.0, a reaction similar to that in the endoplasmic sack of the protozoa. Glucose occurs as an end product of cellulose digestion and cellobiose is probably an intermediate product since cellobiase is present. Because of its cellulose-digesting capacity, E. neglectum is helpful to the host and the relationship between the two is one of symbiosis.