Abstract
Most organic fatty acids are fungicidal and have been used for centuries as antimicrobial agents, originally in the manufacture of soaps. In the last 50 years, however, they have found use both in vitro as yeast and mold inhibitors in food stuffs, and as topical and systemic antifungals. Undecylenic acid (10- undecenoic acid) is an eleven-carbon monounsaturated fatty acid, C11H20O2. A substance found naturally in the body (occurring in sweat), undecylenic acid is produced commercially by the vacuum distillation of castor bean oil, via the pyrolysis of ricinoleic acid. It is an economical antifungal agent and is the active ingredient in many topical over-the-counter antifungal preparations. 1 Undecylenic acid has been shown to be approximately six times more effective as an antifungal than caprylic acid, and is effective in maintaining a healthy balance of intestinal and vaginal flora.2