Robert M. Horowitz; Government Chemist

Robert M. Horowitz, director of the U.S. Department of Agriculture’s Fruit and Vegetable Chemistry Laboratory in Pasadena, has died at the age of 71.

Horowitz, who suffered a heart attack a year ago, died Friday of heart failure at St. John’s Hospital in Santa Monica, his wife, Sylvia, said Tuesday.

Raymond Bennett, his successor and colleague for 20 years, described Horowitz as a world-class scientist recognized internationally for his study of natural product chemistry.

Horowitz had concentrated particularly on flavonoids, chemicals in such foods as the bitter-tasting compounds in grapefruit peel. The flavonoid research led indirectly to a study of the artificial sweetener neohesperidin dihydrochalcone, or neo DHC.

Horowitz, who earned bachelor’s, master’s and doctoral degrees in chemistry at UCLA, was co-author of more than 100 articles and several books stemming from his research.

In 1965 he was awarded the Superior Service Medal by the U.S. Department of Agriculture, and in 1981 he received the Service Through Chemistry Award of the Orange County chapter of the American Chemical Society.

A native of Pittsburgh, Pa., Horowitz joined the federal laboratory in Pasadena as a research chemist in 1955. He became director in 1989 and served until his death.

Earlier in his career, he had worked as a chemist for Shell Development Co. and an instructor of pharmacology at the University of Michigan.

In addition to his wife, Sylvia, of Pasadena, Horowitz is survived by three sons, Jonathan of Pasadena; Daniel, a student at Cambridge University in England, and David of Coldsprings Harbor, N.Y.

The family has asked that any contributions be made in memory of Horowitz to the Huntington Botanical Gardens, 1151 Oxford Road, San Marino 91108, or to the Assn. of Chemists and Biochemists, UCLA Department of Chemistry, Los Angeles 90024.