Metabolomic profiling and antioxidant potential of three fungal endophytes derived from Artemisia annua and Medicago sativa

Abstract

In this work, three fungal endophytes identified as Aspergillus terreus (AFL, AFSt and AFR), were studied for their antioxidant potential. LC-MS-based metabolomics, followed by multivariate statistical analysis were then applied to comprehensively profile their extracts. The three fungal endophytes revealed interesting antioxidant potential, in particular, the strain isolated from the Artemisia annua leaves (AFL), which was rich in different types of phenolic metabolites. Additionally, all fungal-derived ethyl acetate extracts showed potent inhibition against the prooxidant xanthine oxidase. Multivariate analysis (PCA and PLS-DA) demonstrated a unique chemical fingerprint for each strain, where phenolics, coumarins, and polyketides were the discriminative metabolites of the three fungal strains. The present findings highlighted the power of metabolomics in the chemotaxonomical classification of closely related strains. It also asserted the role of fungal endophytes in the management of oxidative stress, particularly when they are utilized in the production of fermented food products.

Graphical Abstract

Keywords:

• Medicago sativa
• Artemisia annua
• fungal endophytes
• Aspergillus terreus
• antioxidant
• LC-MS
• metabolomics
• PCA
• PLS-DA
• oxidative stress
• xanthine oxidase inhibitors

Acknowledgements

We thank M. Müller and M. Krischke (University of Würzburg) for LC-MS measurement.

Disclosure statement

The authors declare there is no conflict of interest.