ISSN 1684–5315 © 2006 Academic Journals

and P. stutzeri (3) were isolated from Nigerian patients with burns, wound and skin infections, UTI, diarrhoea and eye infections. 81.5, 55.6, 76.9 and 33.3 % of these species produced pyocins at a range of 410 – 670 g/ml. High yields of pyocins at 35 – 37oC, which declined sharply at temperatures above 37oC were obtained from all the producing strains. The strains also displayed significant pyocin expression (P < 0.05) under UV irradiation. Pyocins from a total of 25 producing strains; P. aeruginosa (14/27), P. putida (4/9), P. fluorescens (7/13) were inhibitory to the growth of P. putida indicator strain with four strains: PA02, PA20, PP03 and PF01 producing inhibition zone diameter>3 mm. These pyocins also displayed growth inhibitory activity against some Nigerian isolates of Gram-positive and Gram-negative bacteria when undiluted and at 1:2- 1:16 dilutions. The susceptible organisms include Bacillus cereus, Listeria monocytogenes, Klebsiella spp., Staphylococcus aureus, S. epidermidis, Proteus spp. and Vibrio parahaemolyticus. The results of this study have provided evidence for broad-spectrum antibacterial activity of pyocins elicited by Pseudomonas species from Nigeria