2-Bromooctanoic acid is an effective substitute for the expensive (2,000 times) and cell-growth-inhibiting polyhydroxyalkanoic acid synthesis inhibitor, cerulenin. It blocks the formation of polyhydroxyalkanoic acid in Pseudomonas fluorescens BM07 without any influence on the cell growth when grown on fructose. It inhibits β-oxidation of fatty acids in perfused rat liver and in mitochondria isolated from rat liver.