Trachyspermum ammi L. essential oil as plant based preservative in food system

The study reports efficacy of Trachyspermum ammi fruit essential oil (EO) as plant based preservative in food system. GC–MS analysis of EO identified cymene as chief component (76.27%) followed by thymol (13.30%), dl-limonene (3.23%), 1,8-cineole (2.58%) and γ-terpinene (1.68%). The minimum inhibitory (MIC) and minimum aflatoxin inhibitory concentrations (MAIC) of EO were 0.8 and 0.6 μL/mL, respectively, against Aspergillus flavus LHP(C)-D6. Among EO components, thymol showed the highest antifungal and antiaflatoxigenic activity suggesting synergistic mode of action of EO components. Microscopic observations at sub lethal and lethal concentrations of EO using SEM and TEM revealed its mode of action on fungal plasma membrane causing considerable reduction in ergosterol quantity and increased leakages of Ca+2, K+ and Mg+2 from EO treated A. flavus cells. The EO completely inhibited aflatoxin B1 production in wheat and chickpea as analyzed through HPLC and caused no toxicity in seed viability. The LD50 of EO was 6620.43 μL/kg for oral-toxicity on mice and IC50 was 0.467 μL/mL through DPPH analysis. The ajowan EO may thus be formulated as safe plant based preservative for enhancement of shelf life of food items.