In vitro studies were performed to investigate a possible mechanism by which lecithin suppresses intestinal cholesterol absorption. The hypothesis that lecithin acts by retarding the diffusion of micelles across the unstirred water layer (UWL) was tested by measuring cholesterol influxes (Ji) in segments of rat intestine under conditions with no maximal and minimal effective thickness of the UW...

Hanahan and Jayko (1952) isolated a pure individual unsaturated lecithin, L-ox-(dipalmitoleyI)lecithin, from fresh baker's yeast by adsorption on alumina. They showed that hydrogenation of this material produced the corresponding saturated lecithin which was identical with the synthetic L-oc-(dipalmitoyl)-lecithin of Baer and Maurukas (1952). The latter compound, when used in combination with c...

The interactions of proteins during the heat treatment of whey-protein-isolate (WPI)-based oil-in-water emulsions with and without added hydroxylated lecithin were studied by examining the changes in droplet size distribution and the quantity and type of adsorbed and unadsorbed proteins. Heat treatment at 90 degrees C of WPI emulsions resulted in an increase in total adsorbed protein; unadsorbe...

The present studies were undertaken to determine the extent to which the phospholipid composition of Neurosporn crama can be altered by mutations studied in conjunction with controlled supplementation. Previous work in this laboratory has shown that a mutation involving an enzyme concerned with lecithin synthesis can result in a lecithin-deficient strain (1, 2). The methylation of phosphatidyle...

Developments in nanotechnology and in the formulation of liposomal systems provide the opportunity for cosmetic dermatology to design novel delivery systems. Determination of their physico-chemical parameters has importance when developing a nano-delivery system. The present study highlights some technological aspects/characteristics of liposomes formulated from egg or soy lecithins for topical...

About the year 1846 Gobley succeeded in obtaining from egg yolk and other organs a substance of a fat-like nature containing nitrogen and phosphorus which he called lecithin [1846]. This substance was soluble in alcohol and in ether, formed an emulsion when rubbed up with water and yielded fatty acids and glycerophosphoric acid on hydrolysis. These observations of Gobley furnished a basis for t...

In the preceding paper it was shown that a phospholipase prepared,from Penicllium notatum will hydrolyse lecithin only after the, addition,, of a minimum proportion of anionic amphipathic molecules1 e.g. dicetylphosphoric acid, cardiolipin, sodium dodecyl sulphate (Bangham & Dawson, 1959), The onset of hydrolysis occurred, only when the emulsion particles carried a minimum net negative charge, ...

Chemiluminescence (CL) that appears during oxidation of lecithin and ascorbate has been studied. A simple system consisting only of purified lecithin, which has one double bond, and ascorbate as a physiological reductant with a low redox potential, was used. The CL spectrum of lecithin contain a strong band lying in the near infrared, and three bands at 20 900 cm-1, 17 700 cm-1 and 15 800 cm-1,...

A procedure for the enzymatic determination of lecithin and sphingomyelin in aqueous solution is described. The phospholipids are first dissolved in chloroform:methanol (2:1 by vol), the solvent is evaporated, and the residue is redissolved in an aqueous zwitterionic detergent solution. The enzymatic reaction sequences of both assays involve hydrolysis of the phospholipids to produce choline, w...

Lecithin and lecithin/cholesterol dispersions as well as lysolecithin micelles were used to provide basic information on the mechanism of the interaction of zwitterionic phospholipids with dextran sulfate. The addition of dextran sulfate to lecithin dispersions or lysolecithin micelles in the presence of Ca2+ produced insoluble complexes. At each Ca2+ concentration, the amount of insoluble comp...