Precursors of Papaya (Carica papaya, L.) Fruit Volatiles

Oxygenated terpenoids derived from linalool, a major constituent among papaya (C. papaya, L.) fruit volatiles, were studied by capillary gas chromatography (HRGC) and combined capillary gas chromatography-mass spectrometry (HRGC-MS). Using a sample preparation technique suitable for the separation and enrichment of polar compounds, the two diastereoisomers of 6,7-epoxy-linalool, 2,6-dimethyl-1,7-octadiene-3,6-diol, 2,6-dimethyl-3,7-octadiene-2,6-diol, (E)- and (Z)-2,6-dimethyl-2,7-octadiene-l,6-diol, and 2,6-dimethyl-7-octene-2,3,6-triol were identified for the first time. Each of four diastereoisomeric epoxy-linalool oxides in their furanoid and pyranoid forms were also detected for the first time as natural plant constituents. Biogenetic pathways of formation and metabolization of the oxygenated linalool derivatives are discussed.