title: Comparison of the formation of peppery and woody sesquiterpenes derived from α-guaiene and α-bulnesene under aerial oxidative conditions.
abstract: Deuterium-labeled guaiane derivatives and their precursors, namely, d5-2R-rotundol (11a), d5-2S-rotundol (11b), d5-bulnesone (14), d5-2R-bulnesol (16), d7-α-guaiene (10), and d7-α-bulnesene (15), were synthesized in good yields as GC-MS internal standards for comparing the behavior of α-guaiene (1) and α-bulnesene (5) under autoxidative conditions. It was found that approximately 99% of α-guaiene coated onto filter paper and exposed to air at ambient temperature was autoxidized after 48 h and up to 7% of rotundone (3) and 0.6% of rotundols (2a/b) were formed during this period. Autoxidation of α-bulnesene (5) was considerably slower, with approximately 80% remaining after 2 days and yielding less than 1.5% of α-bulnesone (7) and 0.3% and 0.9% of bulnesols 6a and 6b, respectively, after 5 days. The results indicate the feasibility of rapid changes of aroma profiles of herbs and other plant materials over time when exposed to air.
authors: Department of Wine Science, School of Agriculture, Food and Wine, The University of Adelaide , Waite Campus, PMB 1, Glen Osmond, South Australia 5064, Australia.
authors: An-Cheng
authors: AC
authors: Huang
authors: Mark A
authors: MA
authors: Sefton
authors: Dennis K
authors: DK
authors: Taylor
mesh_terms: D052176:Azulenes / Q000737:chemistry*; D005421:Flavoring Agents / Q000737:chemistry*; D009812:Odorants / Q000032:analysis; D010084:Oxidation-Reduction; D012717:Sesquiterpenes / Q000737:chemistry*; D045789:Sesquiterpenes, Guaiane / Q000737:chemistry*
chemical_list: D052176:Azulenes; D005421:Flavoring Agents; D012717:Sesquiterpenes; D045789:Sesquiterpenes, Guaiane; C512113:alpha-bulnesene; C019408:guaiene
keywords: autoxidation; bulnesene; bulnesone; guaiene; rotundone