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A total of 96 lactic acid bacteria (LAB) were isolated from African indigenous fermented products and cow's intestines to study their inhibitory capability against multi-drug-resistant uropathogens. Escherichia coli accounted for approximately 45% of isolated uropathogens, followed by Staphylococcus spp. (20%). The Gram negative uropathogens were highly resistant to quinolones, co-trimoxazole, teicoplanin and some beta-lactams, while the Staphylococcus spp. showed high resistance to aminoglycosides, beta-lactams and macrolides. Twenty-four LAB isolates were selected based on their antimicrobial activity against two uropathogenic Staphylococcus aureus strains and bacteriocin production. LAB strains showing antimicrobial activity were grouped into smaller groups through amplified ribosomal DNA restriction analysis (ARDRA). Representative strains were identified as Weissella spp., Enterococcus faecium, Lactococcus lactis and Lactobacillus brevis through sequencing of 16S rDNA. The Weissella spp. and L. brevis strains demonstrated remarkable inhibitory activity against seven strains of Gram negative uropathogens. Two strains of L. lactis produced a bacteriocin-like inhibitory substance active against Lactobacillus sakei. In this study, an unusual high rate of co-trimoxazole, quinolones and macrolides resistance among uropathogens from south west Nigeria was discovered. Based on their sensitivity to Weissella spp., there is a potential for using these LAB as a natural approach for the protection against the uropathogens assayed.

Sensory, chemical and bacteriological changes were studied in vacuum-packed squid mantles (Todaropsis eblanae) that were pressurised at 150, 200, 300 and 400 megapascal (MPa) for 15 min at ambient temperature and stored at 4 degrees C. Sensory analysis showed that the higher the pressurisation the longer the shelf-life. Thus, the lot pressurised at 400 MPa was rejected after 28 days' storage compared with 7 days for the untreated lot. The chemical results generally corresponded with the sensory ones. Furthermore, ammonia (NH3) and trimethylamine (TMA) were produced in the pressurised lots after a pressure dependent delay. Urea decreased to low levels in all lots with the exception of the 400 MPa lot. Onset of production of agmatine, the dominant amine in this species, and other biogenic amines was delayed by increasing pressure, but still, high concentrations of these amines were detected in pressurised lots of acceptable sensory quality. Microbial counts conducted after 1 day of storage showed that the bacterial load was reduced by all pressures, reaching levels below the detection limit in the lots treated with 200-400 MPa. However, growth was resumed in all lots after a pressure dependent delay. Luminous bacteria predominated initially in the lots pressurised at 300 and 400 MPa, but were outnumbered by Enterobacteriaceae and lactic acid bacteria at the time of sensory rejection of these lots. All colonies isolated prior to pressurisation were identified as Photobacterium phosphoreum. This bacterium also resumed growth faster than other members of the endogenous microflora after pressurisation. All luminous colonies were identified as P. phosphoreum. Lactic acid bacteria isolated at the final sampling point of the lot pressurised at 400 MPa were identified as Carnobacterium piscicola and Carnobacterium divergens, while Serratia liquefaciens and Proteus vulgaris make up Enterobacteriaceae.