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Abstract: The distributions of aliphatic and aromatic terpenoids in Cretaceous and Paleogene angiosperm fossils from Japan were investigated. Aliphatic A ring-degraded oleanane, ursane and lupane were found in all samples. In addition, aliphatic gymnosperm-derived diterpenoids were detected in significant quantities. Aromatic oleanane-type triterpenoids were the major components, with ursane- and lupane-type triterpenoids being minor compounds in all angiosperm fossils. In a Cretaceous gymnosperm fossil, major components included aliphatic labdane-, isopimarane- and abietane-type diterpenoids, aromatic abietane-type diterpenoids, and chrysene- and picene-type polyaromatic hydrocarbons (PAHs). Trace amounts of oleanane-, ursane- and lupane-type triterpenoids were also identified. It is likely that the aromatic triterpenoids were introduced to the gymnosperm fossil from the angiosperm-derived material in the sediments. We defined an angiosperm/gymnosperm index (al-AGI′) as an alternative to the aliphatic triterpenoid/diterpenoid ratio proposed in the literature. The al-AGI′ index may underestimate the angiosperm contribution, because the aliphatic angiosperm-derived triterpenoids are more readily converted to aromatic counterparts than the diterpenoids during diagenesis. An aromatic angiosperm/gymnosperm index (ar-AGI) can be calculated using aromatic diterpenoids and triterpenoids. We suggest that ar-AGI is best calculated using only the oleanane-, ursane- and lupane-type aromatic triterpenoids, and that the chrysene- and picene-type PAHs be excluded. [Copyright &y& Elsevier]

Abstract: The essential oils from a bogwood trunk of sugi (Cryptomeria japonica D. Don) from Sanbe-cho, Shimane, Japan, preserved for c. 3500–3800 years in volcanic ash (S-bogwood), were analyzed using gas chromatography-mass spectrometry (GC/MS). Eight sesquiterpenes and four diterpenes were identified. The main components were simonellite (19.2%), cis-calamenene (11.6%), and α-phyllocladane (8.8%). These results were compared with previous results for oils from a fresh stump of C. japonica, from Muikaichi-cho, Shimane, Japan (fresh wood) and for oils from a stump of another sugi bogwood preserved for c. 3000 years in sediment of a muddy field in Abu-cho, Yamaguchi, Japan (Y-bogwood). Simonellite, α-phyllocladane, selinane (4.3%), and eudalene (2.7%) were identified for the first time in bogwood trunk oil. Ash generated by oxidation of each of the two bogwood samples and fresh wood sample at 700°C was analyzed using scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDXA). The major elements were S and Ca in S-bogwood ash, Fe and Ca in Y-bogwood ash, and K and Ca in the fresh wood ash, respectively. Sulfur in the S-bogwood ash is thought to have come from volcanic ash. The results suggest that S-bogwood was influenced directly by volcanic ash and the degree of terpenoid alteration was more drastic than that of Y-bogwood. [Copyright &y& Elsevier]