A novel acidic homogeneous polysaccharide (AIPW50-1) with a molecular weight of 214. 5 kDa was isolated by hot water extraction and several column chromatographic purification methods from Arca inflata Reeve. The repeating structural units of AIPW50-1 were elucidated by the combined chemical and instrumental analyses. https://yeswellneses.shop/product-category/vitamin-b/