PRODUCTION OF LIMONOATE DEHYDROGENASE BY Pseudomonas

The growth conditions of Pseudomonas sp. 321–18 were studied to maximize yields of limonoate dehydrogenase, which prevents the development of limonin bitterness in citrus juices. The organism grew well on 0.5% or less limonoate media, but it did not grow on media containing 1.0% or more limonoate. Galactose and fructose were excellent substrates for its growth, but sucrose and glucose were found to be poor. The organism grew best at 25°C and pH 7–7.5. Cells grown on substrates other than those containing limonoids did not produce limonoate dehydrogenase, but the enzyme was induced with low concentrations of limonoids. Enzyme activity was increased five to sixfold by use of the induction method on galactose grown cells.