雪灵芝醇提物不同极性萃取部分的体外抗氧化活性

目的:通过体外抗氧化和还原活性评价实验,研究藏药雪灵芝乙醇提取物不同极性溶剂萃取部分的抗氧化作用。方法:用体积分数95%的乙醇回流提取雪灵芝粉末,浓缩的乙醇浸膏依次用石油醚、二氯甲烷、乙酸乙酯、正丁醇进行萃取,各部分分别配制成适当浓度的溶液,采用1,1-二苯基-2-苦基肼(DPPH)自由基法,2,2-连氮-双-(3-乙基苯并噻唑啉磺酸-6)二铵盐(ABTS)自由基法和铁离子还原/抗氧化能力(FRAP)法分别测定各部分的自由基清除能力和铁离子还原力。结果:雪灵芝醇提物的4个萃取部分均具有一定的体外抗氧化作用,其中乙酸乙酯与正丁醇部分清除DPPH·,ABTS+·及还原Fe3+的能力均比二氯甲烷与石油醚部分强。结论:雪灵芝提取物清除能力与提取物样品浓度在一定范围内具有良好的量效关系,其中极性较大的乙酸乙酯部分和正丁醇部分的抗氧化活性及还原能力相对较强。

Antioxidant Activity of Arenaria kansuensis Extracts in vitro

Objective: To investigate the antioxidant activity of Arenaria kansuensis extracts in vitro. Method: The air-dried and powderded herb of A. kansuensis was extracted over 2 hours with 10 times of 95% alcohol refluxing for 2 times and the combined alcohol extracts were concentrated under vacuum drying. The resultant residue was partitioned in petroleum ether, dichloromethane, ethyl acetate and n-butanol orderly. The four extracts were configured to the appropriate solution. The antioxidant activity of four extracts were analyzed by 1,1-diphenyl-2-pieryl-2-picrylhydrazyl (DPPH) radical scavenging, 2,2-amino-di(3-ethyl-benzothiazoline sulphonic acid-6) ammonium salt (ABTS) radical scavenging, and ferric reducing antioxidant power (FRAP) assay. Result: The ethyl acetate and n-butanol extract of A. kansuensis showed stronger scavenging activity against DPPH ·, ABTS⁺ · and reducing antioxidant power of 2,4,6-tris (2-pyridyl) -s-triazine(TPTZ) than other extracts, but showed lower capacity than positive control of vitamin C. Conclusion: The scavenging effects showed a dose-response relationship at the selected concentration with the extracts of A. kansuensis. The ethyl acetate and n-butanol extract have the strongest free radical scavenging activity.