McCook, Kayanne P; Chen, A.R.M.; Reynolds, W.F.; Reese, Paul B.
Author Affiliation, Ana.
The potential of Cyathus africanus for transformation of terpene substrates.
Date of Publication
61 - 66p.
The insecticidal sesquiterpenes cadina-4,10(15)-dien-3-one and aromadendr-1(10)-en-9-one were administered to the fungus Cyathus africanus ATCC 35853. Biotransformation of the former produced (4R)-9á-hydroxycadin-10(15)-en-3-one, while the latter gave 2â-hydroxyaromadendr-1(10)-en-9-one, 2á-hydroxyaromadendr-1(10)-en-9-one and 10á-hydroxy-1â,2â-epoxyaromadendran-9-one. The bioconversion of santonin led to the production of two analogues, 11,13-dihydroxysantonin and the hitherto unreported 8á,13-dihydroxysantonin, while cedrol yielded 3â,8â-dihydroxycedrane and 3á,8â-dihydroxycedrane. Stemod-12-ene, a diterpene, was transformed to 2-oxostemar-13-ene, a hitherto unknown analogue with a rearranged carbon framework. When methyl betulonate, a triterpenoid belonging to the lupane family, was supplied to the fungus 18á-ursane and 18á-oleanane derivatives, namely 19â-hydroxy-3-oxo-18á-oleanan-28-oic acid and 19á-hydroxy-3-oxo-18á-ursan-28-oic acids, were generated. There are no previous reports of fungal transformation of a triterpene in which a skeletal rearrangement occurred. All substrate administration experiments were done in the presence of the terpene cyclase inhibitor chlorocholine chloride (CCC), using the single phase - pulse feed method....