Growth inhibition of the stored fish (Ethmalosa fimbriata) fungus Aspergillus flavus, exposed to extracted essential oils from Callistemon citrinus and Ocimum canum

The aim of this study was to evaluate the antifungal effects of essential oils from Callistemon citrinus and Ocimum canum against Aspergillus flavus. Major components in the oil of C. citrinus were 1,8-cineole (60.6%), α-pinene (18.5%), limonene (5.0%) and α-terpineol (5.0%). The oil of O. canum was mainly composed of 1.8-cineole (20.8%), linalol (14.3%), eugenol (11.9%), terpinen-4-ol (7.4%) and germacrene D (4.9%). Inhibition of the mycelia growth of A flavus increased significantly (p < 0.05) with the essential oils concentrations. Positives correlations were observed between inhibition percentages and the concentration of C. citrinus (p < 0.001; r = 0.873) and O. canum oils (p< 0.001; r = 0.768). O. canum oil was fungicide at 325 ppm while C. citrinus was fungistatic at all the tested concentrations with the highest inhibition percentage means of 89.74 %. Antifungal activity of the essential oil of O. canum was significantly (p < 0.001) higher than that of C. citrinus. Antioxidant activity of O. canum (49.3 mol/l) was significantly (p < 0.001) higher than that from C. citrinus (5.0 mol/l). These observations suggest the possible exploitation of the oils from O.canum and C.citrinus as potential approach for smoked Ethmalosa fimbriata preservation against A. flavus.   Key words: Antifungal effects, Aspergillus favus, Ethmalosa fimbriata, essential oils.