Antioxidant Potential and Chemical Evaluation of Extracts from Endophytic Fungus Lasiodiplodia sp.

Antioxidants are compounds that can eliminate free radicals and are known to prevent cell damage and health disorders, in turn, improving the quality of life of human beings. This study aims to evaluate the presence of antioxidants in ethyl acetate (EtOAc) extracts from Lasiodiplodia endophyte, which was previously isolated and cultivated by our research group, given its ability to produce a variety of metabolites with different chemical and biological properties. The antioxidant activities were determined using ABTS+⋅, DPPH and FRAP. Total phenolic content (TPC) and total flavonoid content (TFC) were evaluated, as well as the NMR metabolomics of extracts. All extracts showed promising antioxidant activity, and optimal results were achieved between the sixth and eleventh days of fungus cultivation. Furthermore, one of the extracts showed no in vivo toxicity against Galleria mellonella for all tested concentrations. The 1H-NMR spectra showed that there are two distinct groups of molecules present in EtOAc extracts obtained from Lasiodiplodia cultivation, and the data corroborate the results concerning antioxidant activity for TPC and TFC. This suggests that it is possible to monitor the chemical profile of fungal extracts using NMR, and to correlate compounds within days of fungus cultivation, along with their antioxidant activities.