Browsing by Author "Fashola, Muibat O."

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Antibacterial activity of lactic acid bacteria isolated from fresh pepper and tomatoes against common food pathogens
    (PSCI Publications, 2014-12-31) Bello, Olorunjuwon O.; Bello, Temitope K.; Fashola, Muibat O.
    This study aimed to investigate the antibacterial activity of lactic acid bacteria (LAB) isolated from fresh pepper and tomatoes against common food borne pathogens. Man Rogosa Sharpe (MRS) broth and agar were used for the isolation of LAB from the food products and whose antagonistic properties were tested against Bacillus cereus, Staphylococcus aureus, Streptococcus sp., E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa using well diffusion assay method. Four LAB species were isolated and these included Streptococcus pyogenes, Enterococcus faecalis, Lactococcus casei and Lactococcus fermentii. The percentage occurrence of LAB species ranged from 11.77% to 35.29%. E. faecalis exerted the strongest antibacterial activity against all selected pathogenic bacteria while L. casei showed the weakest activity. It was concluded that the isolated LAB showed remarkable inhibitory effect against tested pathogenic strains. It is therefore suggested that these potent isolates could be used as a natural bio-preservatives in different food products. However, further in vitro and in vivo studies are required, according to selection criteria, on their application in different food products.
  • Thumbnail Image
    Item
    Partial Purification, Characterization and Application of Bacteriocin from Bacteria Isolated Parkia biglobosa Seeds
    (Natural and Engineering Sciences, 2018-05-14) Bello, Olorunjuwon O.; Babalola, Olubukola O.; Adegboye, Mobolaji; Fashola, Muibat O.; Bello, Temitope K.
    Bacteriocins are proteinaceous toxins produced by bacteria to inhibit the growth of similar or closely related bacterial strains. Fermented Parkia biglobosa seeds (African locust bean) were screened for bacteriocin-producing lactic acid bacteria (LAB) with the characterization of putative bacteriocins. Bacteriocin-producing lactic acid bacteria (LAB) were identified by 16s rDNA sequencing. Molecular sizes of the bacteriocins were determined using the tricine-sodium dodecyl sulphate-polyacrylamide gel electrophoresis (tricine-SDS–PAGE) and effects of enzymes, pH, detergents and temperature on bacteriocin activity investigated, using standard procedures. Bacteriocins production and activities were measured by spectrophotometric analysis. Statistical analysis was carried out using student t-test and Analyses of Variance. Bacteriocigenic LAB isolated were Lactobacillus plantarum Z1116, Enterococcus faecium AU02 and Leuconostoc lactis PKT0003. They inhibited the growth of both Gram-positive and Gram-negative bacteria. The sizes of bacteriocins Z1116, AU02 and PKT0003 were 3.2 kDa, 10 kDa and 10 kDa, respectively. The synergistic effects of characterized bacteriocins and rifampicin tested on organisms showed significant differences (P < 0.05), as compared with the effects of only one of the two. The antimicrobial activity of the three bacteriocins was deactivated after treatment of the cell-free supernatants with proteinase K, papain, pepsin and trypsin. Parkia biglobosa seeds are, therefore, rich in LAB bacteriocins which could be explored. The biosynthetic mechanisms of LAB bacteriocins could be employed in food safety and security, preservation, peptide design, infection control and pharmacotherapy. This should help in the control of undesirable bacteria and in designing more potent and selective antimicrobial peptides.