The influence of naphthenic acids and their fractions on cell membrane permeability

Abstract

© 2015, Serbian Chemical Society. All rights reserved. The influence of naphthenic acids (NAs) mixture and their narrow fractions (called NA pH 4, pH 8 and pH 10) on the permeability of beetroot cell membrane was examined. The results showed that the effect depends on the treatment duration, concentration and the structures of the NAs. Longer treatment of plant cell membranes with sodium naphthenate (Na-naph) resulted in an increase in the membrane permeability (e.g., a 4-hour treatment with Na-naph (c = 100 μmol L^-1) increased the membrane permeability by about 3 times, while prolongation of treatment to 24 h resulted in an 18-fold increase in the effect). NAs in the concentration range from 0.1 to 10 μmol L^-1 did not change membrane permeability, while the membrane permeability increased linearly with increasing concentration from 10-100 μmol L^-1. The fraction pH 8, where bi- and tricyclic carboxylic acids are the most abundant, expressed the strongest effect. These structures were predominant in the total NAs mixture as well. This could explain the similar, but slightly weaker effect of the mixture, compared to the effect of the NAs present in fraction pH 8. The effect of NAs on beetroot cell membrane was between the effects of the tested anionic (SDS and LS) and non-ionic surfactants (Triton X-100).