In this study, the process conditions, physicochemical properties, structural composition and activity of polysaccharides isolated from leechee peel (LPP) by ultrasound-assisted extraction (UAE) with enzyme and alkali solution extraction (ASE) were compared. The results showed that the total sugar content of LPP extracted by UAE accounted for 75.65 %, which was significantly higher than that extracted by alkali solution. The optimum conditions were as follows: extraction temperature of 68.78 ℃, ultrasonic enzymolysis time of 39.68 min, pectinase dosage of 4.03 %, solid–liquid ratio of 1:30 g/mL, and ultrasonic power of 360 W. The antioxidant activities and structure of leechee peel polysaccharide (LPP) prepared under different conditions were compared. It was found that UAE-LPP was an α-type polysaccharide containing 15.83 % uronic acid. Moreover, LPP extracted by UAE showed strong activity in anti-lipid peroxidation and reducing ability. Ultrasound-assisted enzymatic method is an effective means to improve the content and activity of natural plant polysaccharides, and this method has the advantages of short time-consuming, simple process and easy operation, which can greatly improve the utilization rate of polysaccharides and lay a theoretical and scientific basis for the development and utilization of LPP.

中文翻译：

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荔枝皮多糖的超声/酶法提取、特性及比较


本研究比较了超声辅助提取（UAE）与酶提取和碱溶液提取（ASE）从荔枝皮（LPP）中分离多糖的工艺条件、理化性质、结构组成和活性。结果表明，UAE提取的LPP总糖含量占75.65%，明显高于碱液提取的LPP。最佳条件为：提取温度68.78℃、超声酶解时间39.68min、果胶酶用量4.03%、料液比1:30g/mL、超声功率360W。比较了不同条件下制备的荔枝皮多糖（LPP）的含量。结果发现UAE-LPP是一种α型多糖，含糖醛酸15.83%。此外，UAE提取的LPP表现出很强的抗脂质过氧化活性和还原能力。超声辅助酶法是提高天然植物多糖含量和活性的有效手段，该方法具有耗时短、工艺简单、操作方便等优点，可大大提高多糖的利用率，为天然植物多糖的研究奠定了基础。为LPP的开发利用提供理论和科学依据。