The effects of unsaturated fatty acids on Helicobacter pylori in vitro

Division of Biochemical Medicine, Department of Cellular and Molecular Sciences, St George's Hospital Medical School, Cranmer Terrace, London SW17 ORE * Correspondence should be sent to Professor T. C. Northfield. Received July 19, 1994 Accepted September 29, 1994 Surmmary: The effects of three unsaturated free fatty acids on Helicobacter pylori growth in vitro was determined. Growth of H. pylori in Brucella broth was inhibited in a dose-dependent manner by arachidonic, linoleic and oleic acids. The degree of inhibition at any one concentration was related to the degree of fatty acid unsaturation. Triolein, a triacylglycerol ester of oleic acid did not inhibit growth. Inhibition of H. pylori growth was associated with disruption of cell membranes. Incubation with 14 C linoleic acid and 14 C oleic acid showed incorporation of these fatty acids into H. pylori cell mass and phospholipids leading to alteration of the phospholipid composition of the organism. Incorporation was greater with linoleic than oleic acid and this was associated with a greater inhibition of growth. These findings indicate that H. pylori is sensitive to unsaturated free fatty acids through their incorporation into phospholipids and membrane destruction. This may have therapeutic implications.