The concentration of sugar was determined with a KNAUER
high performance liquid chromatograph HPLC Pump K-100 under
the following conditions: KNAUER NH2 column (250 4.6 mm)
at a temperature of 30 C, KNAUER RI detector K-2301, mobile
phase of acetonitrile/ultrapure water at a flow rate of 1 ml/min
and sample size of 20 lL.