Effect of Partially Purified Enterocins from Enterococcus faecalis Strains on the Growth of Some Phytopathogenic Fungi

Plant protection is an important area which needs attention since most of the hazardous inputs added into agricultural systems are in form of synthetic chemicals. The inhibitory activity of partially purified enterocins (PPEs) produced by Enterococcus faecalis strains on plant pathogenic fungi was investigated in this study. The PPEs were preliminarily screened against bacteria using agar-well diffusion method. The active extracts were partially purified using ion exchange chromatography. The in vitro anti-fungal properties of the PPEs were determined using agar dilution and broth dilution techniques. The PPEs tested in this study inhibited the growth of Botryodiplodia theobromae, Aspergillus niger, Pythium ultimum, Penicillium expansum and Fusarium oxysporum. At different concentrations PPEs had varying inhibitory effects on the dry mycelial weight of Pythium ultimum and F. oxysporum. At the 96th hour of the experiment, enterocin UNAD 012 had higher percentage inhibition ranging between 37.63 and 84.11% than enterocin UNAD 046 with percentage inhibition ranging between 28.77% and 67.27% on the test fungi. This inhibitory activity of enterocins produced by E. faecalis on fungi makes them as potential biocontrol agents due to their ability in suppressing their growth. Keywords. Bacteriocin, enterocins, Enterococcus faecalis, fungi, phytopathogens.