Antifungal and antioxidant activity of plant based essential oils on Aspergillus flavus Link (Trichocomaceae) isolated from stored maize grains of Meghalaya

Abstract

Essential oils from five medicinal aromatic plants viz. Gaultheria fragrantissima Wall, Artemisia nilagirica Clarke, Curcuma longa Linn, Zingiber officinale Roscoe and Litsea cubeba (Lour.) Pers. were evaluated for their efficacy as antifungal agents against the growth of toxigenic Aspergillus flavus Link isolated from stored maize of Meghalaya. Antifungal activity of essential oils was evaluated by determining the Minimal inhibition concentration (MIC) and Minimal fungicidal concentration (MFC). Among the five essential oils tested, Litsea cubeba essential oil showed high antifungal activity with complete mycelia growth inhibition at 0.8 µl/ml. Scanning Electron Microscopy of A. flavus exposed to oils showed hyphae and conidiophore damages. The essential oil exhibited antioxidant activity through DPPH (2,2-diphenyl-1-picrylhydrazyl) assay as IC50 value ranged between 0.59 and 14.44 µl/ml and are non-phytotoxic during seed germination experiments with maize seeds. Based on the antifungal, antioxidant and non-phytotoxic potential, the tested essential oils may be recommended as eco-friendly seed protectants.