为探究龙眼核中的主要多酚种类及其抗氧化性能,依次采用超声波辅助提取、有机溶剂萃取、AB-8型大孔树脂和Sephadex LH-20型葡聚糖凝胶树脂分离纯化龙眼核多酚,经液质联用仪鉴定结构,并通过ABTS自由基清除率和FRAP值的测定判断其抗氧化性能。结果表明在最优条件下,超声波辅助提取法的多酚提取量为53.68 mg/g;适宜的萃取溶剂为乙酸乙酯,萃取多酚含量最高,为663.50 mg/g;经2种树脂分离纯化后得到主要多酚组分4,通过结构鉴定为柯里拉京,含量631.18 mg/g;组分4在质量浓度为100μg/mL时,对ABTS自由的清除率和FRAP值分别为(73.90±0.60)%和1766.07±94.39。因此,龙眼核中主要的多酚物质为柯里拉京,且具有优异的抗氧化性能。
In order to explore the main polyphenols in longan seeds and their antioxidative activities, the polyphenols were extracted by ultrasonic-assisted organic solvent extraction. They were separated and purified by AB-8 macroporous resin and Sephadex LH-20 glucan gel resin. The structure was identified by LC/MS. Their antioxidative properties were determined by their ABTS radical scavenging rate and FRAP value. The results showed that the highest amount of polyphenols (663.50 mg/g) were extracted by ultrasonic-assisted extraction followed by using ethyl acetate as an extraction solvent. The main polyphenol component 4 was isolated and purified, which was identified as corilagin with an amount of 631.18 mg/g. Furthermore, 100 μg/mL corilagin were found to be able to scavenge (73.90±0.60)% ABTS, and the FRAP value was (1 766.07±94.39). Therefore, the main polyphenolic substance in longan seeds is corilagin, and it has excellent antioxidative properties.
[1] RANGKADILOK N,WORASUTTAYANGKURN L,BENNETT R N,et al.Identification and quantification of polyphenolic compounds in Longan (Euphoria longana Lam.) fruit[J].Journal of Agricultural and Food Chemistry,2005,53(5):1 387-1 392.
[2] RANGKADILOK N,SITTHIMONCHAI S,WORASUTTAYANGKURN L,et al.Evaluation of free radical scavenging and antityrosinase activities of standardized longan fruit extract[J].Food and Chemical Toxicology,2007,45(2):328.
[3] ZHENG Guoming,XU Liangxiong,WU Ping,et al.Polyphenols from longan seeds and their radical-scavenging activity[J].Food Chemistry,2009,116 (2):433-436.
[4] 全国中草药汇编编写组.全国中草药汇编(下册)[M].北京:人民卫生出版社,1978:445.
[5] 黄晓冬.4种龙眼核提取物的总黄酮含量、体外抗菌活性与抗氧化活性[J].食品科学,2011,32(11):43-47.
[6] 文良娟,李英军,毛慧君,等.龙眼核的营养成分及其活性物质的抗氧化性能研究[J].食品科学,2010,31(1):243-246.
[7] 周凯,胡卓炎,周沫霖,等.龙眼核提取物的体外抗氧化及抑菌活性研究[J].食品与机械,2015(4):167-171.
[8] LI Xiangnan,HUANG Jiale,WANG Zidan,et al.Alkaline extraction and acid precipitation of phenolic compounds from longan (Dimocarpus longan L.) seeds[J].Separation & Purification Technology,2014,124(6):201-206.
[9] LIU Yangbin,WANG Pengpu,CHEN Fang, et al. Role of plant polyphenols in acrylamide formation and elimination[J].Food Chemistry,2015,186:46-53.
[10] KEBE M,RENARD C M C G,MAATAOUI M E,et al.Leaching of polyphenols from apple parenchyma tissue as influenced by thermal treatments[J].Journal of Food Engineering,2015,166:237-246.
[11] 唐福才,姚敦琛,关天旺,等.龙眼核中多酚提取及抗氧化活性的研究[J].食品研究与开发,2015(12):5-9.
[12] 陈金玉,曾健,李春美.龙眼核多酚提取工艺的正交试验优化及其分离纯化与结构表征[J].食品科学,2015,36(16):31-37.
[13] SINGLETON V L,ROSSI J A.Colorimetry of total phenolics with phosphomolybdic-phosphotungstic acid reagents[J]. American Journal Enology and Viticulture,1965,16:144-158.
[14] OZGEN M,REESE R N,TULIO A Z,et al.Modified 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (abts) method to measure antioxidant capacity of Selected small fruits and comparison to ferric reducing antioxidant power (FRAP) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) methods[J]. Journal of Agricultural and Food Chemistry,2006,54(4):1 151-1 157.
[15] ZHANG Shuting,CUI Yan,LI Lingxi,et al.Preparative HSCCC isolation of phloroglucinolysis products from grape seed polymeric proanthocyanidins as new powerful antioxidants [J].Food Chemistry,2015,188:422-429.
[16] PFUNDSTEIN B,EI DESOUKY S K,HULL W E,et al.Polyphenolic compounds in the fruits of Egyptian medicinal plants (Terminalia bellerica, Terminalia chebula and Terminalia horrida):characterization, quantitation and determination of antioxidant capacities[J]. Phytochemistry,2010,71(10):1 132-1 148.
[17] CHEN J Y, XU Y J, GE Z Z, et al. Structural elucidation and antioxidant activity evaluation of key phenolic compounds isolated from longan (Dimocarpus longan, Lour.) seeds[J]. Journal of Functional Foods, 2015, 17(4):872-880.
[18] BENZIE I F F,STRAIN J J.The ferric reducing ability of plasma (FRAP) as a measure of “antioxidant power”:The FRAP assay[J]. Analytical Biochemistry,1996,239(1):70-76.
