Stimulating Materials obtained from Injured and Killed Cells

Abstract

PREVIOUS work of ourselves¹ and others² has shown that ultra-violet radiation appears at times to stimulate cell division in micro-organisms, but that there is little consistency in obtaining the effect. To establish whether or not stimulation of metabolic processes occurs when cells are subjected to lethal ultra-violet irradiation, the respiration of yeast suspensions irradiated with full ultra-violet under various conditions was compared with that of controls. Again inconsistent results were obtained, but definite stimulation occurred in a number of cases. There then followed an investigation of various factors, such as pH, age of organisms, quality and quantity of radiation, etc., which might have accounted for the inconsistencies.