Comparative Study of the Development and Characterization of Ecofriendly Oil and Water Nanoemulsions for Improving Antifungal Activity

Present work aimed to synthesize peppermint and eucalyptus oil-based nanoemulsions by a high-energy sonication process having potent antifungal activity. Tween 80 was used as the most suitable emulsifier by increasing interaction and stability of the system. A relative study was done among eucalyptus oil (ENE) and peppermint oil (PNE) nanoemulsions. PNE had a smaller droplet size (20–40 nm) than ENE (60–100 nm). Because of the smaller droplet size, higher surface area, lower surface tension, and presence of antimicrobial metabolites, PNE exhibited a higher antifungal efficacy as compared to ENE. 1% PNE showed complete inhibition of four fungal phytopathogens, while ENE showed partial inhibition. Stability of ENE was also a limiting factor along with increasing droplet size and resulted in decreased antimicrobial activity. Conclusively, peppermint oil-based nanoemulsion (PNE) proved to be a most promising antimicrobial agent against fungal pathogens; it can be used for sustainable disease management in crop plants.