Efficacy of chemically characterized Piper betle L. essential oil against fungal and aflatoxin contamination of some edible commodities and its antioxidant activity

The study investigates fungal contamination in some dry fruits, spices and areca nut and evaluation of the essential oil (EO) of Piper betle var. magahi for its antifungal, antiaflatoxigenic and antioxidant properties. A total of 1651 fungal isolates belonging to 14 species were isolated from the samples and Aspergillus was recorded as the dominant genus with 6 species. Eleven aflatoxin B-1 (AFB(1)) producing strains of A. flavus were recorded from the samples. Eugenol (63.39%) and acetyleugenol (14.05%) were the major components of 32 constituents identified from the Piper betle EO through GC and GC-MS analysis. The minimum inhibitory concentration (MIC) of P. betle EO was found 0.7 mu l/ml against A. flavus. The EO reduced AFB(1) production in a dose dependent manner and completely inhibited at 0.6 mu l/ml. This is the first report on efficacy of P. betle EO as aflatoxin suppressor. EO also exhibited strong antioxidant potential as its IC50 value (3.6 mu g/ml) was close to that of ascorbic acid (3.2 mu g/ml) and lower than that of the synthetic antioxidants such as butylated hydroxytouene (BHT) (7.4 mu g/ml) and butylated hydroxyanisole (BHA) (4.5 mu g/ml). P. betle EO thus exhibited special merits possessing antifungal, aflatoxin suppressive and antioxidant characters which are desirable for an ideal preservative. Hence, its application as a plant based food additive in protection and enhancement of shelf life of edible commodities during storage and processing is strongly recommended in view of the toxicological implications by synthetic preservatives. (C) 2010 Elsevier B.V. All rights reserved.