Abstract: | Freezing of Act. noursei cell suspensions at a rate of 0.5 degrees per minute in the presence of various substances showed that 5 per cent concentrations of glycerol, ethylen-, diethylen-, propylenglycol and polyethylenglycols had a cryoprotective effect. Polyethylenglycols with a molecular weight of 1500-20 000 had the highest protective effect on the actinomycetous cells from the damaging action of repeated freezing and thawing. The method of repeated freezing and thawing is recommended for studying the cryoprotective effect of various compounds. |