Extraction, Purification And Biological Activities Of Polysaccharides From Amomum Villosum Lour.

Objective:Fructus Amomi, the dried and ripe fruit of Amomum villosum Lour from Zingiberaceae. It is often used to eliminate damp and improve appetite, to warm the spleen and check diarrhea. But there was little research on the ASP currently. Fructus Amomi as a traditional Chinese herbal medicine treatment for gastrointestinal disorders, which polysaccharide has strong biological activity, therefore biological activity of ASP was worth studying. In this study, systematically optimize extraction of ASP was research, then separation and purification of ASP. At last, ASP and its purified fractions were preliminary pharmacological test research. Provide a theoretical basis for the development of ideal ASP drugs and corresponding products.Method:In the present study, the ultrasonic-assisted method was performed for the extraction of ASP. On the basis of single-factor experiments, the relationship between main extraction conditions including extraction time, the ratio of water to raw material and temperature was modeled using a3-factor,3-level Box-Behnken experimental design and studied the yield of polysaccharides. And then, the established model was analyzed by response surface methodology to obtain the optimum extraction conditions. Furthermore, the crude ASP was purified by DEAE-cellulose-52ion exchange column chromatography and further purified through a Sephadex G-100column to afford the purified polysaccharide. Then, the antioxidant and anticancer activities in vitro of crude ASP and its purified fractions were evaluated; the scavenging activities of superoxide anion, hydrogen peroxide and DPPH radical of the crude ASP and its purified fractions were investigated. Finally, low immunity induced by cyclophosphamide in mice to investigate ASP of immunocompromised mice immune organ weight, macrophage phagocytosis, spleen hemolysin effects, to evaluate the immunomodulatory activity of ASP.Result:1. The optimum extraction conditions were obtained as follows:extraction time was71min, the ratio of water to raw material was39:1(v:m, mL·g-1) and temperature was78℃. Under these conditions, the observed values of maximal yield of polysaccharides was13.04±0.36%(n=3). Consistent with the theoretical value and actual value2. The crude ASP was sequentially purified by chromatography of DEAE-52and Sephadex G-100, resulting in three purified fractions of ASP-1, ASP-2and ASP-3. Crude ASP and its purified fractions (ASP-1, ASP-2and ASP-3) showed scavenging activities on superoxide radical, hydroxyl radical and DPPH radical. And ASP-3possessed strong scavenging activities on superoxide radical, hydroxyl radical and DPPH radical. ASP and its purified fractions scavenging activity were significantly superior to vitamin C on the superoxide anion.3. ASP was able to improve clearance ability and phagocytic speed of mice peritoneal macrophage. Increase the content of serum hemolysin, thymus and spleen index, and improve the immune capacity in mice.Conclusion:The study showed that, ultrasonic assisted extraction process parameters of ASP by RSM were stable and reliable; ASP and its purified fractions have excellent antioxidant effect; ASP has immunomodulatory effects, and was able to improve the body immunity activity. ASP has good biological activity, could be used for further research and development corresponding pharmaceutical and function health products, for the development of Fructus Amomi to a new level...