Gpc 20a

A UV–visible spectrophotometer (SP-756P, Shanghai Spectrum Instruments Co., Ltd, Shanghai, China) was used to check the presence of proteins and nucleic acids of WCP. High-performance gel-permeation chromatography (HPGPC) (Shimadzu-GPC-20A, Kyoto, Japan) was used to determine the average molecular weight of WCP (1 mg/mL) with a chromatographic column (TSK-gel GMPWXL column, TOSOH, Tokyo, Japan). The experimental conditions were as follows: temperature of column, 35 °C; temperature of detector, 35 °C; injection volume, 20 μL; mobile phase, 0.1 N NaNO₃ and 0.06% NaN₃ water solution; flow rate, 0.6 mL/min. The standard of Pullulan (Narrow MWD) was used to establish the standard curve, and the standard curve was used to calculate the average molecular weight of WCP [52 (link)].

Phenol-sulfuric acid method was used to analyze the content of total polysaccharides in TMP. A UV spectrophotometer (200–600 nm, Mipta UV-3100PC, China) was used to detect the protein content. The molecular weight and homogeneity of TMP were determined by a high-performance gel permeation chromatography (HPGPC) (Shimadzu, GPC-20 A, Japan) coupled with a differential refractive index detector-20 (RID-20 A) and a gel chromatography column (Waters No. WAT011525). 20µL of TMP solution (2.5 mg/mL) was injected to analyze. The flow rate was set at 1 mL/min, the column temperature at 35 °C and the detector temperature at 40 ℃. Glucose (T26300, T12600, T5800, T4290, T1400, T1030, T633, T342, T180, T150) was used as the standard.