Evaluating the probiotic potential of Yeasts isolated from Ethiopian traditionally fermented foods and dairy products

Abstract

Fermented foods were most prepared products for their benefits of health such as medicinal, therapeutic and probiotic effects. These effects were due to potential probiotic microorganisms such as lactic acid bacteria and yeasts. The purpose of this study was to evaluate the probiotic characteristics of yeasts isolated from Ethiopian traditionally fermented foods and dairy products. The isolates identified and subjected to analyses to determine their probiotic properties. From the selected isolates ten were found to be resistant and showed good growth at pH 2, 2.5and 3for 24h and were able to grow at both 25, 37 and 45°C but best growth was found at body temperature 370C. The three isolates namely Y66, Y82 andY36 showed maximum growth at pH 2.5 with corresponding mean OD value of 1.45, 1.40 and 1.09. From the finding insolate Y77 and Y82 performed well at pH 2.5 and 3 compared to other isolates. The three isolates GB48, Y77 and Y82 shown highest growth rate with mean OD630nm value of 2.25, 1.85 and 1.78 respectively at 370C. Isolates were also investigated for bile salt tolerance, cholesterol assimilation, co aggregation and antioxidant abilities. IsolateY76 and Y82 were found to be with highest bile salt tolerant and cholesterol assimilation of 46.56, 56.20% and 96.11, 92.11% of assimilation respectively. The two isolates Y77 and Y82 also showed good survival rate of 44.59 and 36.56% in gastrointestinal fluid and antioxidant scavenging ability of 44.59 and 36.00% respectively. Among these isolates Y82, Y76 and Y77 have been found to bear with promising desirable probiotic potentials properties.