Influence of plant terpenoids on the permeability of mitochondria and lipid bilayers

Five sesquiterpene alcohol esters of the carotane series, from plants of th e genus Ferula were investigated with regard to their capacity to modify th e ion permeability of both planar lipid bilayers and mitochondria. These co mpounds are subdivided into two structural groups that differ in their effe cts on membrane permeability. Complex esters of sesquiterpene alcohols Mirt h aliphatic acids. which constituted the first,group (lapidin and lapiferin ). do not possess ionophoric properties. The second group comprised complex esters of sesquiterpene alcohols with aromatic acids (ferutinin. tenuferid in and ferutidin). all of which increase cation permeability of lipid bilay ers and mitochondria in a dose-dependent manner. A pronounced selectivity o f the terpenoid-modified membranes for divalent cations versus monovalent c ations was found. Evidence of a earner mechanism for terpenoid-induced ion transport is demonstrated. A tentative complex composed of a divalent catio n with two molecules of membrane-active terpenoid is proposed. (C) 2001 Els evier Science B.V. All rights reserved.