Examination of pH Tolerance Test of Two Alkalitolerant Yeasts

Abstract:

The purpose of this paper is to examine the pH adaptability range of two yeasts from our laboratory, and applied turbidimetry and Bradford methods to examine growth of Trichosporon asahii XJU-1 and Rhodotorula mucilaginosa XJU-1.It is shown that Trichosporon asahii XJU-1 grown between pH2.0 and pH13.0 and optimum pH is 8.0, whereas Rhodotorula mucilaginosa XJU-1 grown between pH3.0 and 12.0，optimum pH is 8.5. When turbidimetry was applied, it produced consensus results between pH4.0 and 10.0 with Bradford method. At the same time, produced senior distorted at pH<4.0 and pH≥10.0.Bradford method indirect determined total soluble protein of Trichosporon asahii XJU-1 is 290μg/mL at optimum pH8.0, Rhodotorula mucilaginosa XJU-1 is 164μg/mL at optimum pH8.5, respectively. Compared with turbidimetry, Bradford method embodied its accuracy in whole pH ranges. It is concluded that both two tested yeasts have wider pH tolerant ranges and can be two new members of alkali-tolerant yeast family.