布渣叶多糖的提取工艺优化及生物活性分析

刘秋叶; 刘辉; 陈鑫; 左亚杰

doi:10.13386/j.issn1002-0306.2023090110

布渣叶多糖的提取工艺优化及生物活性分析

Optimization of Extraction Process of Polysaccharides from Microcos paniculata and Its Biological Activity Analysis

摘要

摘要: 目的：优化布渣叶多糖的提取工艺，并对布渣叶多糖体外抗氧化、胰脂肪酶抑制、抗菌活性进行评价。方法：采用超声辅助热水法提取布渣叶多糖，在单因素实验基础上结合正交试验对提取工艺参数进行优化；通过测定DPPH、ABTS⁺和OH自由基清除能力来评价布渣叶多糖的抗氧化能力；通过抑制胰脂肪酶作用测定布渣叶多糖的降脂活性；采用微量肉汤稀释法测定布渣叶多糖对大肠杆菌、金黄色葡萄球菌、铜绿假单胞菌、鲍曼不动杆菌和肺炎克雷伯菌的抑菌作用。结果：布渣叶多糖最佳提取工艺条件为：超声功率225 W，超声温度65 ℃，料液比1:20（g/mL），超声时间35 min，在此条件下多糖平均得率为3.76%±0.25%；布渣叶多糖对DPPH、ABTS⁺、OH自由基清除率的IC₅₀值分别为0.1430、0.01553和0.1451 mg/mL；在布渣叶多糖质量浓度为5 mg/mL时，布渣叶多糖胰脂肪酶抑制率为36.22%±1.76%；此外，布渣叶多糖对铜绿假单胞菌、大肠杆菌、肺炎克雷伯菌、鲍曼不动杆菌均有抑制效果，其MIC分别为50、100、100、200 mg/mL。结论：单因素结合正交试验优化所得提取工艺可有效提取布渣叶多糖，布渣叶多糖具有良好的体外抗氧化、抗菌活性以及有潜在的胰脂肪酶抑制能力，有深入开发研究的价值。

Abstract: Objective: To optimize the extraction process of polysaccharides from Microcos paniculata, and evaluate the antioxidant, antibacterial and pancreatic lipase inhibitory activities of Microcos polysaccharide. Methods: Ultrasonic-assisted extraction method was employed to extract polysaccharides from Microcos paniculata. The single-factor experiments were combined with orthogonal experiment to optimize the parameters of the extraction process. Antioxidant activity of Microcos polysaccharide was evaluated by DPPH, ABTS⁺, and OH free radical scavenging assays. The pancreatic lipase test was used to study the lipid lowering activity of Microcos polysaccharide. In addition, the antibacterial activity of Microcos polysaccharide against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae were measured by the micro broth dilution method. Results: The optimum conditions of Microcos polysaccharide were as follows: Ultrasonic power was 225 W, extraction temperature was 65 ℃, solid-liquid ratio was 1:20 (g/mL), extraction time was 35 min. Under these conditions, the yield of Microcos polysaccharide was 3.76%±0.25%. Microcos polysaccharide exhibited potent scavenging activity on DPPH, ABTS⁺ and OH free radicals, with the half-inhibitory concentrations were 0.1430, 0.01553 and 0.1451 mg/mL, respectively. The inhibition rate of pancreatic lipase was 36.22%±1.76%, when the concentration of Microcos polysaccharide was 5 mg/mL. The minimum inhibitory concentrations of Microcos polysaccharide against P. aeruginosa was 50 mg/mL, against E. coli and K. pneumoniae were all 100 mg/mL, against A. baumannii was 200 mg/mL. Conclusion: The extraction process optimized by single factor experiments combined with orthogonal experiment could effectively extract Microcos polysaccharides. The Microcos polysaccharide revealed good antioxidant and antibacterial as well as potential pancreatic lipase inhibitory activities, which would be valuable for in-depth developmental research.