Effect of steryl glycosides on the phase transition of dipalmitoyl lecithin.

The phase transition of dipalmitoyl lecithin, measured by thermal analysis, was eliminated by the plant sterol, sitosterol, and by the derivatives steryl glucoside and acylated steryl glucoside, which were isolated from soybean lipids.When digitonin was added to dipalmitoyl lecithin-sterol mixtures, in amounts equimolar to sterol, the phase transition of the phospholipid was revealed presumably because of the formation of a sterol complex. When digitonin in molar excess of sterol was added, the endothermic peak disappeared again.