Browsing by Author "Alabi A. A."

Now showing 1 - 1 of 1
  • Item
    ANTIMICROBIAL ACTIVITIES AND BACTERIOCINS OF LACTIC ACID BACTERIA ISOLATED FROM NIGERIA INDIGENOUS FERMENTED COWMILK “NUNU”
    (Ceylon Journal of Science, 2024) Saliuand B.K.; Abdulkadir H.; Dadzie V.O; Alabi A. A.; Salami R.I.; Ajewole A.E.
    Nunu is a nutritious fermented yoghurt-like milk beverage that can serve as a source of lactic acid bacteria (LAB) with antimicrobial and bacteriocin potentials. LAB were isolated from nunu samples using MRS agar and screened for antimicrobial activity against test organisms. Three LAB, namely Lactobacillus parafarraginis OCLP1, L. fermentum CSL58 and L. buchneri MZE12 out of a total of 14 isolates produced antimicrobial activity against Bacillus anthracis CHF-2011-32b, B. cereus DHM5-1, Providencia vermicola KSVDL-09-71600, P. rettgeri SIRT3, P. stuartii SILT11 and other test organisms. Antimicrobial factors were assayed in LAB cell-free extracts (CFE), neutralized CFE, and ammonium sulphate precipitants of the CFE, and Lactobacillus parafarraginis OCLP1 demonstrated the highest activity with zones of inhibition of 20.33±3.51 mm , 13.33±1.09 mm and 25.33±2.52 mm, respectively. The CFE of the LAB especially L. parafarraginis OCLP1 demonstrated wide activity spectra by inhibiting both the Gram-positive and Gram-negative bacteria tested. Result of plasmid curing of the LAB indicated that the bacteriocins of L. parafarraginis OCLP1 was plasmid-encoded while the others have their gene clusters on the chromosome. This study concluded that bacteriocin- producing LAB can be found in “nunu” and recommend the use of the isolated LAB as starters in fermented food production after ensuring their safety through toxicological studies.