Assessment of Thymus vulgaris L. essential oil as a safe botanical preservative against post harvest fungal infestation of food commodities

A total of 14 odoriferous angiospermic essential oils were tested against the toxigenic strain of Aspergillus flavus. The essential oil of Thymus vulgaris L. showed highest antifungal efficacy. The thyme oil absolutely inhibited the mycelial growth of A. flavus at 0.7 mu l ml(-1) and exhibited a broad fungitoxic spectrum against eight different food contaminating fungi viz. Fusarium oxysporum, Cladosporium herbarum, Curvularia lunata, Aspergillus terreus, Aspergillus niger, Aspergillus fumigatus, Alternaria alternata and Botryodiploidia theobromae. The oil also showed significant antiaflatoxigenic efficacy as it completely arrested the aflatoxin B-1 production at 0.6 mu l ml(-1). Thyme oil as fungitoxicant was also found superior over most of the prevalent synthetic fungicides. The LC50 of thyme oil against mice was recorded as 7142.85 mu l kg(-1) body weight indicating its non-mammalian toxicity and strengthening its safe exploitation as preservative for stored food commodities. The findings recommend the thyme oil as potential botanical preservative in eco-friendly control of biodeterioration of food commodities during storage. (c) 2008 Elsevier Ltd. All rights reserved.