Chirality of the gamma-lactones formed by Fusarium poae INRA 45.
A filamentous fungus, Fusarium poae INRA 45, was grown in two liquid Czapek-type media (a Czapek medium, and a yeast extract plus casaminoacids-enriched Czapek medium). Eight gamma-lactones, i.e., gamma-penta-, gamma-octa-, gamma-nona-, gamma-deca-, and gamma-dodecalactone, (6Z)-gamma- and (6E)-gamma-dodecenolactones, and a di-unsaturated gamma-dodecalactone, were tentatively, or conclusively, identified by capillary gas chromatography (GC) and coupled GC-MS, in the volatile fractions of the cultures. Kinetics of the formation of gamma-dodecalactone, (6Z)-gamma- and (6E)-gamma-dodecenolactones, (three major lactones), and gamma-dodecalactone (a minor lactone) were quantitatively studied by computerized GC integration. Variations of the (R/S) ratios of the lactone enantiomers were quantitatively studied by computerized multidimensional gas chromatography (MDGC) integration. The levels of the lactones were superior in the enriched Czapek-type medium to those of the Czapek medium, but the compositions of these media did not influence significantly the (R/S) ratios of these lactones. Formation of the enantiomers is discussed in terms of metabolism of potential precursors.
National Institute for Agronomical Research (INRA), Flavor Research Laboratory, Dijon, France.
A
A
Latrasse
E
E
Guichard
C
C
Piffaut
N
N
Fournier
L
L
Dufosse
D002849:Chromatography, Gas; D003470:Culture Media; D005670:Fusarium / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D007700:Kinetics; D007783:Lactones / Q000737:chemistry* / Q000378:metabolism; D008968:Molecular Conformation; D013237:Stereoisomerism
D003470:Culture Media; D007783:Lactones