FMPS3, the main fraction of FMPS, was isolated by DEAESepharose CL-6B column chromatography. According to size-exclusion chromatography, multi-anglelaser light-scattering and refractive index (SEC-MALLS-RI), the molecular weight (Mw), polydispersityindex (Mw/Mn) and root-mean-square turning radius (Rg) of FMPS3 were 4.58 × 105(±2.02%) Da, 1.08(±1.23%), 28.13 (±1.73%) nm, respectively.