三地羊肚菌菌丝体胞外多糖分离纯化及降血糖和抗氧化活性研究

Extraction and isolation of Morchella eohespera mycelium extracellular polysaccharides and its hypoglycemic and antioxidant activities

中文关键词:  三地羊肚菌菌丝体  胞外多糖  理化性质  降血糖活性  抗氧化活性

英文关键词:Morchella eohespera mycelium  extracellular polysaccharides  physicochemical properties  hypoglycemic activity  antioxidant activity

中文摘要:

      目的 以三地羊肚菌菌丝体胞外多糖(Morchella eohespera mycelium extracellular polysaccharides, MEP)为研究对象, 采用DEAE琼脂糖凝胶FF (DEAE Sepharose Fast Flow)柱层析纯化得到多糖MEP-H和MEP-N, 分别对其理化性质、体外降血糖活性和抗氧化活性进行分析。方法 通过碳水化合物含量测定、紫外扫描分析、傅里叶变换红外光谱分析和扫描电子显微镜对多糖MEP-H和MEP-N进行理化性质研究; 通过α-淀粉酶抑制率、α-葡萄糖苷酶抑制率、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl, DPPH)自由基清除能力、2,2’-联氮-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐[2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt, ABTS]阳离子自由基清除能力、还原力和超氧阴离子清除能力, 评价MEP-H和MEP-N的体外降血糖活性和抗氧化活性。结果 三地羊肚菌菌丝体胞外多糖MEP-H和MEP-N碳水化合物含量分别为(78.12±0.14)%和(77.37±0.03)%。降血糖研究表明, 当质量浓度0.75 mg/mL时, MEP-H和MEP-N对α-淀粉酶抑制率最高, 分别为(8.06±1.93%)和(11.08±1.05)%; 质量浓度0.50 mg/mL时, MEP-H和MEP-N对α-葡萄糖苷酶抑制率最高, 分别为(74.93±2.72)%和(69.48±2.97)%。抗氧化研究表明, MEP-H和MEP-N在质量浓度分别为4 mg/mL、2 mg/mL时达到最佳DPPH自由基清除活性, 清除率分别为(47.54±10.88)%和(47.16±6.91)%; 质量浓度为8 mg/mL时, MEP-H和MEP-N的最大ABTS阳离子自由基清除率分别为(8.67±0.53)%和(17.00±4.21)%, 最大还原力吸光值分别为0.13±0.004和0.17±0.008, 最大超氧阴离子清除率分别为(40.95±6.02)%和(29.87±3.18)%。结论 羊肚菌菌丝体胞外多糖MEP-H和MEP-N均具有降血糖活性和抗氧化活性, 本研究为液态发酵羊肚菌的深入研究提供了理论依据。

英文摘要:

      Objective To study the Morchella eohespera mycelium extracellular polysaccharides (MEP), purify MEP-H and MEP-N by DEAE Sepharose Fast Flow column chromatography, and analyze their physicochemical properties, hypoglycemic activities, and antioxidant activities in vitro. Methods The physicochemical properties of MEP-H and MEP-N were studied by carbohydrate content determination, analysis of ultraviolet scanning, Fourier transform infrared spectroscopy analysis, and scanning electron microscopy. The hypoglycemic activities and antioxidant activities of MEP-H and MEP-N were evaluated by α-amylase inhibition rate, α-glucosidase inhibition rate, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging ability, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt (ABTS) cationic free radical scavenging ability, reducing power and superoxide anion scavenging ability. Results The carbohydrate content of MEP-H and MEP-N was (78.12±0.14)% and (77.37±0.03)%, respectively. Hypoglycemic studies showed that at a mass concentration of 0.75 mg/mL, MEP-H and MEP-N had the highest α-amylase inhibition rates, which were (8.06±1.93)% and (11.08±1.05)%, respectively; at a mass concentration of 0.50 mg/mL, MEP-H and MEP-N had the highest α-glucosidase inhibition rates, which were (74.93±2.72)% and (69.48±2.97)%, respectively. Antioxidant studies showed that MEP-H and MEP-N achieved the best DPPH free radical scavenging activity at mass concentrations of 4 mg/mL and 2 mg/mL, with scavenging rates of (47.54±10.88)% and (47.16±6.91)%, respectively; at a mass concentration of 8 mg/mL, the maximum ABTS cationic free radical scavenging rates of MEP-H and MEP-N were (8.67±0.53)% and (17.00±4.21)%, respectively, the maximum reducing power absorbance values were 0.13±0.004 and 0.17±0.008 respectively, and the maximum superoxide anion scavenging rates were (40.95±6.02)% and (29.87±3.18)%, respectively. Conclusion Both MEP-H and MEP-N, the extracellular polysaccharides from the mycelium of Morchella eohespera, exhibit hypoglycemic and antioxidant activities. This study provides a theoretical basis for further research on liquid fermentation of Morchella eohespera.