As one of the main components in , polysaccharides was potentially to be developed for the special physiochemical properties and bioactivity. However, the low extraction efficiency of polysaccharides (IOP) significantly hindered the in-depth research and development. To achieve a higher extraction yield of IOP, subcritical water was selected and optimized by Box-Behnken Design (BBD) with a more reasonable yield investigation method in the present study. In addition, for the comparative analysis, the physiochemical properties and bioactivity of the subcritical water extracted polysaccharides (IOP-S), purified polysaccharides (IOP-P) and hot water extracted polysaccharides (IOP-W) were all investigated and analyzed. The results showed that the optimal extraction conditions were 200°C, 13.24 min and 30:1 (mL/g), which corresponded to a polysaccharide yield of 14.14±0.17 %. With simple purified process, the IOP-P with high purity (total sugar content of 87.55 %) was suitable for the further study. Compared to IOP-W, a wider molecular weight range (3.4–98 kDa) of polysaccharide was found in IOP-S, as well as higher sugar and polyphenol content, which might be the main reason for the well antioxidant and digestion enzyme inhibition activity. There were also various differences in the monosaccharide composition, micro-morphology and other physiochemical properties, which all suggested that the subcritical water could efficiently extract a special IOP for the fourthly study and development. In summary, the present study proved that subcritical water extraction could significantly improve the extraction efficiency of IOP, and the basic information in physiochemical properties and bioactivities of IOP would promote the development of IOP in the future.

中文翻译：

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采用亚临界水提取的桦褐孔菌多糖：提取优化、理化性质和生物活性分析


多糖作为主要成分之一，因其特殊的理化性质和生物活性而具有开发潜力。然而，多糖（IOP）的提取效率较低，严重阻碍了深入研究和开发。为了获得更高的IOP提取率，本研究通过Box-Behnken设计（BBD）选择并优化了亚临界水，并采用了更合理的收率调查方法。此外，为了进行比较分析，还对亚临界水提取多糖（IOP-S）、纯化多糖（IOP-P）和热水提取多糖（IOP-W）的理化性质和生物活性进行了研究和分析。结果表明，最佳提取条件为200℃、13.24min、30:1(mL/g)，多糖得率为14.14±0.17%。纯化工艺简单，所得IOP-P纯度较高（总糖含量87.55%），适合进一步研究。与IOP-W相比，IOP-S中的多糖分子量范围更宽（3.4-98 kDa），糖和多酚含量更高，这可能是其具有良好的抗氧化和消化酶抑制活性的主要原因。单糖组成、微观形态和其他理化性质也存在各种差异，这都表明亚临界水可以有效地提取特殊的IOP用于第四次研究和开发。综上所述，本研究证明亚临界水提取可以显着提高IOP的提取效率，并且IOP理化性质和生物活性的基础信息将促进IOP未来的发展。