Fatty Acid Composition of Total Lipids in Membrane under Abiotic Stress

Effects of abiotic stress (osmotic and oxidative) on fatty acid composition of vacuolar membrane lipids of beet roots (Beta vulgaris L., variety Modana) was investigated. The results of the experiments showed that one of the major adaptive responses under hyperosmotic and oxidative stresses was associated with an increased content of saturated fatty acids (FAs). Most significant upward changes in the percentages of fatty acids in lipids under stress conditions were observed for lauric (C12:0), myristic (C14:0), and stearic (C18:0) acids and downward changes, for linoleic acid (C18:2). Hyperosmotic and oxidative stress caused an increase in the microviscosity of the vacuolar membrane, which was affirmed by a decrease in the double bond index down to values of 1.00 and 0.93, respectively, as compared to the control value (1.11). We conclude that the vacuolar membrane is involved in the mechanisms of the plant cell response and adaptation to stress factors.