2-HYDROXYHEXADECANOIC AND 8,9,13-TRIHYDROXYDOCOSANOIC ACID ACCUMULATION BY YEASTS TREATED WITH FUMONISIN-B-1

Fumonisin B1 is a sphingolipid-like compound that enhances the accumul ation of yeast sphingolipids and 2-hydroxy fatty acids. These lipids o ccur both as freely extractable and cell bound components in yeast fer mentations. Both free and bound 2-hydroxy fatty acids produced by Pich ia sydowiorum NRRL Y-7130 were increased when fumonisin B1 (50 mg/L) w as added to the usual growth medium containing yeast extract/malt extr act/peptone/glucose. Fumonisin-treated cultures contained 38 mg/L more 2-hydroxyhexadecanoic and 15 mg/L more 2-hydroxyoctadecanoic acids th an did untreated cultures. By contrast, fumonisin inhibited the accumu lation of free 8,9,13-trihydroxydocosanoic acid in Rhodotorula sp. YB- 2501 cultures, leading to 240 mg/L lower trihydroxy acid production th an by untreated cultures.