Figure 2. The weight-average molecular weight assay of WSC1-5 with HPLC.

The retention time and weight-average molecular weight of (A) WSC1, (B) WSC2, (C) WSC3, (D) WSC4 and (E) WSC5 were measured by an Agilent 1,260 gel permeation chromatography equipped with a refractive index detector. Chromatography was performed on TSK G3000-PWXL columns, using 0.2 M CH₃COOH∕0.1MCH₃COONa aqueous solution as the mobile phase at a flow rate of 0.8 mL/min with a column temperature of 30°C. The sample concentration was 0.3% (w/v). The standards used to calibrate the column were dextrans with Mw of 1,000, 5,000, 12,000, 25,000 and 50,000 Da.