Chemical and Biological Investigation of the Endophytic Aspergillus terreus (SU5) Inhabiting Date Fruits (Phoenix dactylifera)

Abstract

Endophytic fungi associated with date fruits (Phoenix dactylifera) are mostly under-explored, despite their potential as reservoirs of natural compounds. The aims of this study were to characterize the endophytic fungus Aspergillus terreus (SU5) isolated from date fruits, and to investigate its biological activities and chemical profile for the first time. Morphological and molecular methods were utilized to identify Aspergillus terreus. A liquid chromatography–mass spectrometry analysis (LC/MS/MS) was conducted to determine the chemical profile of the crude extract. Biological properties were investigated through acetylcholine esterase and butyrylcholine esterase inhibition, cytotoxicity assays against MCF-7 and MCF-7/Adr, and antioxidant assays. LC/MS/MS of the fungal extract resulted in the detection of 39 of established secondary metabolites, primarily comprising polyketides, quinones, and phenolic derivatives. The crude extract demonstrated significant antioxidant activity, especially in the ABTS assay (IC50 = 50.18 μg/mL), considerable cytotoxicity against MCF-7 breast cancer cells, diminished efficacy against the drug-resistant MCF-7/Adr cell line, and preferential inhibition of butyrylcholinesterase compared to acetylcholinesterase. While none of the identified compounds are novel, numerous metabolites are documented here for the first time from an endophytic A. terreus associated with date fruits. The findings underscore date fruits as a prospective ecological niche for a chemically varied endophytic fungus with potential pharmaceutical significance.