The fruit peel of Punica granatum was collected, extracted and evaluated for its anti-bactericidal activity on Agrobacterium tumafaciens, Erwinia amylovora and Pseudomonas solanscearum and its fungicidal effects on R. solani, P. infestans, A. alternate and F. oxysporum. Its combination with a standard bactericide (streptomycin sulfate) and a standard fungicide was also studied. GC-Mass spectroscopy (GC-MS) identification of the bioactive constituents was also carried out. The obtained P. granatum extract was less effective against the three tested bacteria than the standard bactericide although their combination completely prevented A. tumefaciens, E. amylovora and P. saloranacearum growth. Generally, the fungicidal effects differed as a function of the treated fungus owing to different sensitivity of the fungus to the extract bioactive components. P. infestans was the most sensitive, followed by F. oxysporum to this combination. A. alternata occupied the last place in sensitivity to this combination.

P. granatum crude extract weakly stimulated the PPO activity of P. infestans and P. infestans. Twenty compounds were identified in the extract of P. granatum peel sample. including 1,2,3-Trihydroxy benzene (6.20%), Epicatechin-gallate (1.02%), Catechin (1.00%), Methyl-dodecanoate (2.90%), Methyl-tetradecanoate (2.70%), Methyl-hexadecanoate (35.4%), n-Hexadecanoic acid (6.8%), 9-Octadecenoic acid methyl ester (18.40%), Methyl-octadecanoate (5.90%), 6-Tridecyl-tetrahydro-2H-pyran-2-one (3.70%), Methyl-linoleiate (1.68%), Octadecanoic acid (1.9%), Eicosane (1.87%), Heptacosane (0.98%), Unknown (1.25%), Unknown (1.28%), 1,3,5-Trimethyl-2-octadecyl- cyclohexane (0.58%), 9-Octadecenamide (0.76%), Unknown (0.7%) and A glucoside derivative (2.50%).