Fast Screening Method for Detecting Lysine-producing Yeasts

Abstract

Aim: To screen for active Lysine -producing yeasts. Study Design: Examination of different kinds of fruits. Place and Duration of Study: Department of Applied Microbiology and Brewing, Nnamdi Azikiwe University, Awka, from January, 2014 and July, 2015. Methodology: Yeast isolates (100) recovered from different fruits were screened for lysine producers on solid agar medium. Halo growth of the lysine auxotroph, Escherichia coli, seeded in the agar medium indicate lysine production by the yeast isolate. Lysine accumulation in submerged medium by the isolate was examined. Results: Five of the yeast isolates observed to be active lysine producers accumulated lysine yields of 0.20 µg/ml to 0.90 µg/ml in submerged medium. The lysine level accumulated in the broth culture of the yeast was observed to be proportional to the halo growth of the Escherichia coli on solid agar medium. Conclusion: Yeasts capable of producing lysine were isolated from fruits and a fast screening method for their detection on solid agar medium have been identified.