The activity of chaulmoogra acids against Mycobacterium leprae

The activity of the crude sodium salts of the fatty acids of chaulmoogra oil and of hydnocarpic and chaulmoogric acids against Mycobacterium leprae was studied in mouse footpad infection. Multiplication of the organisms was inhibited when the salts were administered intraperitoneally and subcutaneously 3 times per week, and when chaulmoogric acid was administered intraperitoneally 5 times per week in half the equivalent dose. Dihydrochaulmoogric acid was also active, whereas palmitic acid was not. Hydnocarpic acid administered intraperitoneally once per week in a dose equivalent to half that of the sodium salts of the chaulmoogra fatty acids was not effective. The demonstration that chaulmoogra fatty acids possess activity against M. leprae lends weight to our earlier suggestion that a study of compounds analogous to these acids may yield effective antimicrobial agents with a unique mechanism of action.