Secondary metabolites from Penicillium corylophilum isolated from damp buildings

Abstract

Indoor exposure to the spores and mycelial fragments of fungi that grow on damp building materials can result in increased non-atopic asthma and upper respiratory disease. The mechanism appears to involve exposure to low doses of fungal metabolites. Penicillium corylophilum is surprisingly common in damp buildings in USA, Canada and western Europe. We examined isolates of P. corylophilum geographically distributed across Canada in the first comprehensive study of secondary metabolites of this fungus. The sesquiterpene phomenone, the meroterpenoids citreohybridonol and andrastin A, koninginin A, E and G, three new alpha pyrones and four new isochromans were identified from extracts of culture filtrates. This is the first report of koninginins, meroterpenoids and alpha pyrones from P. corylophilum. These secondary metabolite data support the removal of P. corylophilum from Penicillium section Citrina and suggest that further taxonomic studies are required on this species.

• alpha pyrone
• indoor environment
• isochroman
• koninginin
• meroterpenoid

Acknowledgments

This research was financially supported by an NSERC IRC to JDM and an Ontario Graduate Scholarship (OGS) to DRM. We thank Don Belisle (Paracel Inc., Ottawa) for isolates, Dr Tharcisse Barasubiye (AAFC, Ottawa) and Dr Keith Seifert (AAFC, Ottawa) for confirming the identifications and Dr Dan Sørensen for NMR data acquisition. Blake Green provided valuable assistance in the laboratory.