Antioxidant Activity Relationships of Pachymaran Derivatives

Abstract

In this study, carboxymethyl, sulfated and carboxymethyl-sulfated derivatives of pachymaran were prepared. According to the results of chemical analysis and Fourier Transform Infrared spectrums, the modification was successful. The scanning electron microscopy suggested that the structure of native pachymaran was damaged when the samples were treated with different chemical reagents. The antioxidant activities of all the samples were investigated including ferric-reducing power assay, superoxide scavenging assay, hydroxyl scavenging assay and lipid peroxidation inhibition assay. The result indicated that different derivatives exhibited different antioxidant activity on free radicals. The carboxymethylpachymaran showed stronger antioxidant activity on hydroxyl radical (EC50 = 2.3 mg/mL) than sulfated pachymaran but lower ability on superoxide anion (EC50 = 2.5 mg/mL). While, compared with carboxymethylpachymaran and sulfated pachymaran, carboxymethyl-sulfated pachymaran showed the highest antioxidant abilities on ferric-reducing power, hydroxyl radicals scavenging (79.4%), superoxide radicals scavenging (84.2%) and lipid peroxidation inhibition (63.2%) of the three derivatives. Practical Application Poria cocos, namely Fuling, has been widely accepted as a traditional health-maintaining food in the Orient, e.g., in China, Japan and Korea, and has many culinary and medical uses such as anti-inflammatory, antitumor, complement activating and immune stimulating activities. Fungi polysaccharides are now being considered to be a rich source of antioxidants, and the modified pachymaran can be widely used in the medicinal, functional food and other industries.