[Effect of the quality of fat substrate on the dynamics of fatty acid utilization during biosynthesis of cephalosporin C]. / Izuchenie vliianiia kachestva zhirovogo substrata na dinamiku potrebleniia zhirnykh kislot v protsesse biosinteza tsefalosporina C.

Influence of the quality of the fats used on their utilization in the process of cephalosporin C fermentation and accumulation was studied. A decrease in the level of all the fractions of the fatty acids was observed during the fermentation process. The antibiotic yield with the use of oxidized fats was lower. Treatment of the fats with gaseous nitrogen prevented their oxidation. It was supposed that the decreased yields of the antibiotic were associated with the influence of the oxidized fats on the biosynthetic processes.

[Levels of free fatty acids and calcium absorption in giant squid axons at rest and upon stimulation]. / Soderzhanie svobodnykh zhirnykh kislot i pogloshchenie Ca v gigantskom aksone kal'mara v pokoe i pri vozbuzhdenii.

Nine free fatty acids (FFA) were discovered in the squid axons at rest: 12:0, 14:0, 15:0, 16:0, 16:1, 18:0, 18:1, 20:3, 20:4. The relative amount of FFA equaled 14.1 micrograms per mg of lipids. Stimulation of nervous conductors decreased the amount of acids--14:0, 15:0, 16:1, 20:3. Simultaneously a considerable increase of the content of 20:4 was observed and three new fatty acids 20:0, 20:1, 22:2 appeared. The content of FFA increased to 27.2 micrograms/mg of lipids. Calcium absorption in the squid axons was equal to 23 nmol/g, but under stimulation this parameter increased to 37 nmol/g. Exogenous fatty acids brought about also an increase of calcium absorption. The accumulation of FFA under excitation was suggested to be the result of the increase of phosphoinositides content and related to the regulation of Ca transport.