Naringin from Coffee Inhibits Foodborne <i>Aspergillus fumigatus</i> via the NDK Pathway: Evidence from an In Silico Study

Abstract

In the tropics, coffee has been one of the most extensively cultivated economic crops, especially Arabica coffee (Coffea arabica L.). The coffee pulp, which includes phytochemicals with a proven antifungal action, is one of the most insufficiently utilized and neglected byproducts of coffee refining. In the current experiment, we carried out in silico screening of the isolated Arabica coffee phytochemicals for antifungal activity against Aspergillus fumigatus: a foodborne fungus of great public health importance. As determined by the molecular docking interactions of the library compounds indicated, the best interactions were found to occur between the nucleoside-diphosphate kinase protein 6XP7 and the test molecules Naringin (−6.771 kcal/mol), followed by Epigallocatechin gallate (−5.687 kcal/mol). Therefore, Naringin was opted for further validation with molecular dynamic simulations. The ligand–protein complex RMSD indicated a fairly stable Naringin-NDK ligand–protein complex throughout the simulation period (2–16 Å). In ADME and gastrointestinal absorbability testing, Naringin was observed to be orally bioavailable, with very low intestinal absorption and a bioavailability score of 0.17. This was further supported by the boiled egg analysis data, which clearly indicated that the GI absorption of the Naringin molecule was obscure. We found that naringin could be harmful only when swallowed at a median lethal dose between 2000 and 5000 mg/kg. In accordance with these findings, the toxicity prediction reports suggested that Naringin, found especially in citrus fruits and tomatoes, is safe for human consumption after further investigation. Overall, Naringin may be an ideal candidate for developing anti-A. fumigatus treatments and food packaging materials. Thus, this study addresses the simultaneous problems of discarded coffee waste management and antifungal resistance to available medications.

Keywords

• coffee
• <i>Aspergillus fumigatus</i>
• nucleoside diphosphate kinase
• in silico
• antifungal