In vitro screening for human probiotic potentials of Lactobacillus tucceti CECT 5920 and Lactobacillus mindensis TMW isolated from Nigerian Fermented foods

• Published in: The bioscientist (Awka, Nigeria) Nigeria), 2019-09, Vol.6 (1)
• Main Author: C. N Obi
• Format: Article
• Language: English
• Subjects: Bacteriocin; fermented food; in vitro; LAB; probiotic
• ISSN: 2630-7103; 2630-7111

In vitro Probiotic potentials of Lactic acid bacteria (LAB) isolated from traditional fermented foods namely: ugba, ogi, fermenting cassava and kunu-zaki were studied. Twenty five (25) samples each of the four types of fermented foods were serially diluted in sterile peptone water 0.1ml aliquots of appropriate dilution was streaked on De Man Rogosa Sharpe (MRS) agar containing 50mg of nystatin for the isolation of LAB. 48 LAB isolates were recovered from the samples these were screened for bacteriocin production by the Agar Well Diffusion assay and two best bacteriocin producers characterized by molecular method as Lactobacillus tucceti CECT 5920 and Lactobacillus mindensis TMW were tested for their human probiotic potentials. Typed cultures of Staphylococcus aureus NCTC 8325 and Escherichia coli 0157:H7 were used as test pathogens. L. tucceti CECT 5920 and L. mindensis TMW had the same level of bacteriocin production and antimicrobial activity (P≤0.05). The LAB isolates resisted the pH range of 2-8 for 24 hrs while higher bile salt assimilation was shown by L. tucceti CECT 5920. Both LAB strains tolerated pepsin enzyme after 72 hrs. Cholesterol assimilation was better with L mindensis TMW. Both LAB strains did not show any haemolytic effect. L. tucceti CECT 5920 was sensitive to Cotrimoxazole while L mindensis was resistant to all the antibiotics tested.  L. tucceti CECT 5920 gave better results as a LAB isolate with better probiotic potentials than L mindensis TMW.