Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2025
Erindi/veggspjald / Talk/poster V95
Höfundar / Authors: Maonian Xu (1), Elín Soffía Ólafsdóttir (1)
Starfsvettvangur / Affiliations: Faculty of Pharmaceutical Sciences, University of Iceland
Kynnir / Presenter: Maonian Xu
Chiral compounds of natural origins usually occur in one major enantiomeric form. Enantiomers may have drastically different bioactivity and toxicological profiles. Usnic acid (UA) enantiomers in lichens are potentially excellent candidates to study enantiomer biosynthesis: 1) both enantiomers are produced in multiple lichen-forming fungal families, 2) enantiomers have different antibiotic activities, and only the (+)-UA has been associated with therapeutical applications. This study aims to characterize the biosynthesis of usnic acid enantiomers in the lichen-forming fungal family Parmeliaceae. Determination of usnic acid enantiomers is performed by a chiral high performance liquid chromatography (HPLC) method. Fungal phylogenetic tree is constructed by concatenating three fungal loci, i.e. nrITS, MCM7 and RPB1. A chiral HPLC method has been developed and validated for quantitative analysis of usnic acid enantiomers. There is a strong phylogenetic pattern for enantiomeric biosynthesis: the cetrarioid clade is producing the (-)-usnic acid, while the parmelioid clade the (+)-usnic acid, indicating evolutionary divergence of the biosynthetic genes.