Anti-fungal action of bioconverted eicosapentaenoic acid (bEPA) against plant pathogens

Bioconverted eicosapentaenoic acid (bEPA), obtained from Pseudomonas aeruginosa PR3, was assessed for its in vitro and in vivo anti-fungal potential. Mycelial growth inhibition of the tested plant pathogens (Rhizoctonia solani, Botrytis cinerea, Fusarium oxysporum, Fusarium solani, Phyptophthora capsici, Sclerotinia sclerotiorum and Colletotrichum capsici) was measured in vitro. bEPA at the concentration of 5 mu l/ml inhibited 52-60% fungal mycelial growth for all of the plant pathogens in vitro except S. sclerotiorum. Minimum inhibitory concentrations (MICs) of bEPA were found in the range of 250-500 mu g/ml. Also, bEPA had a detrimental effect on spore germination for all the tested plant pathogens. Three plant pathogenic fungi (F. oxysporum, P. capsici and C. capsici) were subjected to an in vivo anti-fungal screening. bEPA at the initial concentration of 3000 mu g/ml had a 100% anti-fungal effect against all of the tested plant pathogens. Concentrations of bEPA corresponding to 1500, 500 and 300 mu g/ml were applied to the plants and revealed promising anti-fungal effects, supporting bEPA as a potential anti-fungal agent. (c) 2007 Elsevier B.V. All rights reserved.