Rhodotorula mucilaginosa,
a producer of the auxiliary enzyme gluconolactonase (GL; EC 3.1.1.17) needed
for the enzyme activity assay, was grown in 1 L flasks in a shaker at 30 ◦C, 300 rpm
in a medium containing 150 g L−1 glucose, 30 g L−1 malt extract and 3 g L−1 soya
peptone for 48 h. Approximately 16 g and 32 g (wet cell mass) of Z. mobilis and R.
mucilaginosa, respectively, were obtained per Liter under the cultivation conditions
specified above.