Essential oil from Teucrium luteum subsp. flavovirens: optimization of yield extraction using response surface methodology, molecular docking and biocontrol against apple gray mold caused by Botrytis cinerea

The extraction of essential oil from Teucrium luteum subsp. flavovirens (TLEO) was carried out using hydrodistillation and three extracting parameters were optimized by a response surface methodology using a central composite design. The optimal conditions for the highest produced yield (0.92%) were found to be a drying period of 7 days, an extraction time of 120 min and a water/plant ratio of 10 ml/g. The antifungal activity was further tested in vitro against Botrytis cinerea-caused apple post-harvest gray mold utilizing poisoned food (PF) and volatile activity (VA) methodologies. The minimum inhibitory concentration was 2 mu L/mL in the VA test, while >2 mu L/mL in the PF method. Additionally, a molecular docking analysis was performed to predict the inhibitory activities of major constituents of TLEO against the 14 alpha-sterol demethylase enzymes (PDB ID: 1EA1) target. This studied oil can provide good alternatives to synthetic fungicides, to control gray rot and preserve apple quality.