*4.1. Preparation of Sulfated Polysaccharides*

*Saccharina japonica* (Laminariaceae), cultured along the coast of Dandong, China, was collected in August 2015, authenticated by Prof. Lanping Ding and stored as a voucher specimen (No. 83) in the Institute of Oceanology, CAS. The fresh algae were promptly washed, sun dried and kept in plastic bags at room temperature until use. FPS and UF were prepared according to our previous methods with minor modifications (Figure 8) [12,26]. Briefly, FPS was extracted in water solution at 120 ◦CC using autoclave from *Saccharina japonica*. DF was prepared using ascorbate and hydrogen peroxide (30 mmol/L, 1:1) degradation method. UF were obtained using DEAE-Sepharose FF exchange chromatography previously described.

**Figure 8.** Flowchart of the extraction for UF.
