ISOLATION AND ANTIBIOGRAM OF PROBIOTIC LACTIC ACID BACTERIA FROM TIGERNUT MILK IN AWKA, NIGERIA

Abstract

Since viable probiotic bacteria as dietary supplements have attracted a great deal of research interest, Different sources of food especially fresh agricultural produce such as nuts and vegetables have become excellent reliable sources of probiotics from Lactic acid bacteria (LAB). In this research,  Tigernut milk samples, produced from an agricultural root crop were used  for the isolation of probiotic Lactic acid bacteria. Among the samples, four isolates were identified as: Lactobacillus sp, Streptococcus sp, Lactococcus sp and Pediococcus sp  based on their morphological and biochemical characteristics. The Isolates were resistant to NaCl (2.0% to 4.4%), exhibited luxuriant growth at low pH (in the acidic condition), while maximum growth was observed at pH around pH 4.4 The isolates were examined for their antibacterial activity against six different test pathogens , which resulted to the effective inhibition of all test pathogens, with maximum inhibitory activity against Staphylococcus aureus (26.1 mm) and minimum was against Pseudomonas aeruginosa (8 mm) . The results of the present research strongly suggest that, Tigernut milk obtained from Awka metropolis is a great source of probiotic Lactic acid bacteria. Extensive research on the isolation and optimization of Lactic acid bacteria from Tigernut milk is required for development of probiotic enriched food supplements for our great benefit.