Chemical Studies on Egg-White Medium for the Cultivation of Endamoeba histolytica

Abstract

Egg-white medium in Florence flasks of 250 ml. capacity was stored up to 20 days and the overlay analyzed for reducing substances, nitrogenous compounds, and fats. Diffusion of reducing substances neared completion after 2 and 8 days at 10[degree] and 37[degree] respectively; diffusion of nitrogenous compounds was most rapid during the first 8 days but had not reached com-pletion at 20 days. Reducing substances were calculated as glucose, arid nitrogenous material as ovomucoid. Fatty substances were found indiffusible. Curves were plotted for standardizing medium used in the cultivation of Endamoeba histolytica, insofar as the glucose content and the ovomucoid content of the overlay were concerned. Consumption of O''2 by the egg-white base was measured from air confined above this base. Reduction of O''2 content occurred amounting to 1 ml. per 125 ml. of air. These data are in agreement with a theory that components of egg white affecting the growth of E. histolytica may be inactivated by oxygenation during storage of the sterile medium. CO''2 was given off by the base but the figures for this gas showed no consistent trends.