Enzymatic degradation products from a marine polysaccharide YCP with different immunological activity and binding affinity to macrophages, hydrolyzed by alpha-amylases from different origins.

YCP is a marine polysaccharide with anti-tumor and immune-modulating effects. This study evaluated the effect of enzymatic degradation of YCP by alpha-amylases from different origins on its immunological activity and binding ability to the macrophages. YCP was hydrolyzed by alpha-amylases isolated from Aspergillus oryzae, Bacillus licheniformis, Barley malt, and Porcine pancreas respectively, then four fragments with unique molecular weight (termed: YCP-Ao, YCP-Bl, YCP-Bm, and YCP-Pp, respectively) were obtained. The four fragments showed different immunological activity and the ability to bind to macrophages. Among them, YCP-Ao possessed almost equivalent immunological activity compared to the original YCP, while such properties were not retained in YCP-Bl. Our further study showed that YCP-Ao prevented YCP from binding to macrophages. In conclusion, YCP-Ao and YCP might have similar active regions.