DIVERSITY AND ANTIBACTERIAL POTENTIAL OF CULTURABLE COASTAL MARINE BACTERIA

The diversity and antibacterial activities of culturable bacteria from the coastal area of the Niger Delta in Bonny Island were investigated. The bacteria were isolated from water, sediment, submerged wood, boat swab, periwinkle (Tympanotonus fuscatus) surface, periwinkle (Tympanotonus fuscatus) intestine, prawn (Penaeus notialis) surface, prawn (Penaeus notialis) fluid, crab (Sesarma huzardi) surface, crab (Sesarma huzardi) fluid, fish (Sarotherodon melanotheron) surface, fish (Sarotherodon melanotheron) intestine and alga (Cladophora sp.) by spread plate procedure. The isolates were screened for antibacterial activity via agar well diffusion technique. Isolates with high antagonistic potential were identified by molecular method. The highest bacterial load was obtained from sediment. A sum of 124 bacterial isolates belonging to the genera of Bacillus, Staphylococcus, Flavobacterium, Pseudomonas, Citrobacter, Enterobacter, Escherichia, Salmonella, Aeromonas, Vibrio, Achromobacter, Erwinia, Acinetobacter, Actinobacillus, Alteromonas, Enterococcus, Serratia, Yersinia, Pleisomonas, Myriodes, Providencia, Shigella, Azotobacter, Proteus, Streptococcus and Shewanella were isolated at dissimilar frequencies with Bacillus predominating. The bacteria isolated from the samples were mostly gram negative. The highest generic diversity was encountered in sediment. About 43% of the isolates showed antagonistic activity. Antagonistic bacteria were more in sediment than in any other sample. Molecular identification of the isolates with high antagonistic potential revealed that they are closely related to Pseudomonas sp. H7, Providencia vermicola strain 6G, Proteus mirabilis strain NM 42-8, Shewanella sp-C16-M, Vibrio parahaemolyticus, Proteus mirabilis RUC 51, Shewanella upenei strain 9.2, Shewanella sp. L-10, Providencia vermicola strain 6G, Shewanella algae strain SW19, Myroides odoratimimus strain SK 505 GRD, Providencia rettgeri strain DSR5, Myroides odoratimimus strain DB13253, Shewanella sp. JNU-SGY002, Myroides odoratimimus DB13253 and Myroides odoratimimus strain Ick58. The results revealed that coastal marine location habours varied bacteria of antibacterial significance against fish and human pathogens.