The aims of this study were to test the efficacy of essential oil of Allium cepa against food spoilage and
food-borne pathogenic microorganisms and its antioxidant activity. The essential oil revealed an interesting
antimicrobial effect against the tested microorganisms with the MIC and MBC values in the ranges
of 0.18e1.80 mg/mL and 0.54e3.6 mg/mL, respectively. The antioxidant activities of the essential oil were
investigated and the oil showed moderate antioxidant activities in ABTS assay (0.67 mg/mL as IC50 value),
DPPH test (IC50 value ¼ 0.63 mg/mL) and metal chelating assay (IC50 value of 0.51 mg/mL). Furthermore,
the reducing power of the oil was dose dependent, and the reducing capacity of the oil was inferior to
butylated hydroxytoluene, which is known to be a strong reducing agent. It was suggested that the
essential oil from A. cepa may be a new potential source as natural antimicrobial and antioxidant agents
applied in food systems.
2012 Elsevier Ltd. All rights reserved