Enzyme-assisted extraction, characterization, and antioxidant activity of polysaccharides from .

INTRODUCTION

Potentilla anserina (.), also known as ginseng fruit, is a plant that can be used as both medicine and food. . has high medical value in Chinese medicine, such as strengthening the spleen and stomach, replenishing qi and blood, and astringing hemostasis.

METHODS

In this study, polysaccharides of . were extracted from the root using an enzyme-assisted extraction method. According to the principle of Box-Behnken design, response surface methodology was designed to optimize the extraction conditions. Fourier transform infrared spectroscopy and scanning electron microscopy were used to investigate the structure and appearance of . polysaccharides. The monosaccharide composition of . polysaccharides was determined using high-performance liquid chromatography. The antioxidant activities were also studied.

RESULTS

Under the optimal extraction conditions (the ratio of solid to liquid, 1:15; ratio of cellulase to pectinase, 1:2; extraction pH, 8.0; enzyme reaction temperature, 60°C), the extraction yield of . polysaccharides was 19.80 ± 0.01%, equal to the model prediction value 19.84%. The data of Fourier transform infrared spectrum, scanning electron microscopy, and high-performance liquid chromatography showed that the . polysaccharide was a kind of α-pyran polysaccharide, mainly consisting of galactose, glucose, rhamnose, and arabinose. The antioxidant results showed that . polysaccharides had a strong hydroxyl radical scavenging ability (IC = 0.367 mg/mL), superoxide anion scavenging ability (IC = 45.017 mg/mL), and a certain degree of total reducing ability.

DISCUSSION

Enzyme-assisted extraction is an efficient method to extract . polysaccharides. The . polysaccharides could have potential use in functional foods as a natural antioxidant.