Concentricol, a taxonomically significant triterpenoid from Daldinia concentrica

Area of Science:

• Mycology
• Natural Product Chemistry
• Chemotaxonomy

Background:

• Xylariaceous Ascomycetes, including Daldinia species, are known for producing diverse secondary metabolites.
• Chemotaxonomy utilizes chemical compounds to classify and understand fungal relationships.
• Previous studies have identified various metabolites in Daldinia, but a comprehensive chemotaxonomic analysis is ongoing.

Purpose of the Study:

• To identify and characterize major metabolites from the ascostromata of Daldinia concentrica.
• To investigate the distribution of these metabolites across various Daldinia species globally.
• To assess the chemotaxonomic significance of identified metabolites within the Daldinia genus.

Main Methods:

• Isolation and identification of a major metabolite from Daldinia concentrica ascostromata.
• Analytical High-Performance Liquid Chromatography with Ultraviolet/Visible detection (HPLC-UV/Vis) and diode array detection.
• Positive electrospray ionization High-Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS) of stromatal methanol extracts.

Main Results:

• A novel, highly oxidized squalene derivative, named concentricol, was isolated and identified.
• Concentricol was found to be omnipresent in the ascostromata of Daldinia concentrica and Daldinia eschscholzii.
• Other Daldinia species investigated lacked concentricol but contained distinct metabolites like binaphthalenes, benzophenones, and azaphilones.

Conclusions:

• Concentricol is a significant chemotaxonomic marker for distinguishing Daldinia concentrica and Daldinia eschscholzii.
• The presence or absence of concentricol, alongside other secondary metabolites, provides valuable insights into Daldinia species delineation.
• This study enhances the chemotaxonomic understanding of the Daldinia genus through metabolite profiling.