CHARACTERISTICS OF THREE YEAST STRAINS FOR WASTEWATER TREATMENT

Abstract

The selection of desirable strains with certain activities that have quick adaptivity and effectively remove contaminants from water is of great importance for the technologies for biological wastewater treatment.Three yeast strains are investigated. One of them was isolated from soil, and others are provided by a yeast strains’ collection and denoted as C1 and C2. The identification of the yeast strains is done using the test kit API 20 C Aux (Biomerieux, France) for rapid identification of yeasts. Determination of the enzyme profile is obtained by applying the test kit API ZYM (Biomerieux, France). The three yeast strains accumulate high concentrations of viable cells. They are similar in their ability to oxidize S – containing compounds (elemental S, Na₂S₂O₃) under alkaline conditions lowering the рH of the medium and to exhibit catalase activity. Yeast strain Y exceeds the rest in the expression of lipolytic activity. That is confirmed in the subsequent analysis of its enzyme profile through identification system API ZYM.  Through it are found and alpha –, beta – glucosidase and aminopeptidase activities.