Assessment of Melissa officinalis L. essential oil as an eco-friendly approach against biodeterioration of wheat flour caused by Tribolium castaneum Herbst.

Abstract

The study reports efficacy of Melissa officinalis L. essential oil (MOEO) as a safe plant-based insecticide against Tribolium castaneum Herbst (TC) by induction of oxidative stress. MOEO nanoencapsulation in chitosan matrix was performed to enhance its bioefficacy. GC-MS analysis of MOEO depicted geranial (31.54%), neral (31.08%), and β-caryophyllene (12.42%) as the major components. MOEO showed excellent insecticidal potential in contact (100% mortality at 0.157μL/cm2) and fumigant bioassays (LC50 = 0.071μL/mL air) and 100% repellency at concentration ≤ 0.028μL/cm2. Increased reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), and decreased ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) at the LC50 dose suggested significant oxidative stress on TC in MOEO treatment sets. The encapsulated MOEO exhibited enhanced activity as fumigant (LC50 = 0.048μL/mL air) and showed significant antifeedant activity in situ (EC50 = 0.043μL/mL). High LD50 value (13,956.87μL/kg body weight of mice) confirmed favorable toxicological profile for non-target mammals. The findings depict potential of nanoencapsulated MOEO as an eco-friendly green pesticide against infestation of stored food by TC.