Assessment of some essential oils as food preservatives based on antifungal, antiaflatoxin, antioxidant activities and in vivo efficacy in food system

The present study strengthens the food preservative potential of plant essential oils (EOs) viz. Origanum majorana L. Coriandrum sativum L. Hedychium spicatum Ham. ex Smith, Commiphora myrrha (Nees) Engl., and Cananga odorata Hook.f. & Thomson based on their antifungal, antiaflatoxin. and antioxidant efficacy. The essential oils were found more efficacious than some prevalent organic preservatives viz salicylic acid, BHT, ascorbic acid and gallic acid as they inhibited the growth and aflatoxin secretion of the aflatoxigenic strain Aspergillus flavus (LHP-6) at lower concentrations. The minimum inhibitory concentration of EOs against the toxigenic strain of A. flavus ranged between 2.0 mu l/ml and 3.0 mu l/ml. In addition, the EOs exhibited broad fungitoxic spectrum against nine food borne molds and strong antioxidant activity. The IC50 value of the oils ranged between 1.3 and 21.67 mu l/ml while their total phenolic content ranged between 2.90 and 33.33 mu g/mg. All the EOs except C odorata showed non-phytotoxic nature on germination of chickpea seeds. During in vivo investigations in food system all the five essential oils showed above 50% protection of chickpea seed from A. flavus infestation showing their potential as plant based preservatives for enhancement of shelf life of food items. (C) 2012 Elsevier Ltd. All rights reserved.