Value of a Simple Observational Technique for Determining the Fat Content of Algal Cells

Abstract

DURING the period 1953–55 an investigation was made of the survival of freshwater algæ during dry periods¹. Some attention was paid to the accumulation of fat in the cells of diatoms and other algæ though details of this work have not yet been published. The method used to investigate fat accumulation was a simple one in which cells were measured in length and in width in girdle view. For some cells the width in valve view was also measured. Fat globules, stained with sudan black, were measured and a note made of the number of fat globules within each particular size range, present in each cell. On the basis of these results, determinations could be made, for comparative purposes, of the mean relative amount of fat per cell in sample populations. The results suggested that fat accumulation was invariably associated with drying in those species investigated which included Pinnularia viridis, P. appendiculata, Nitzschia palea, N. frustulum in addition to Microspora stagnorum.