龙眼核提取物的体外抗氧化及抑菌活性研究  

In vitro antioxidant and antimicrobial activities from longan(Dimocarpus longan Lour.)seed extracts

作　　者：周凯[1] 胡卓炎[1] 周沫霖[1] 赵雷[1] 

机构地区：[1]华南农业大学食品学院,广东广州510642

出　　处：《食品与机械》2015年第4期167-171,共5页Food and Machinery

基　　金：国家荔枝龙眼产业技术体系项目(编号:CARS-33-15);广东省科技计划项目(编号:2013B02050212)

摘　　要：探讨龙眼核中不同极性部位的体外抗氧化和抑菌活性,并筛选其有效部位。以Folin-Ciocalteu比色法测定龙眼核95%乙醇提取物中4种不同极性萃取物的总酚含量,并利用ABTS法、DPPH法、邻苯三酚自氧化法、邻二氮菲—Fe2+氧化法测定评价各萃取物的抗氧化活性,同时采用牛津杯法测定比较4种萃取物的抑菌活性。结果表明:乙酸乙酯萃取物的总酚含量最高,达到(693.51±9.52)mg/g;在不同的自由基体系中,4种萃取物均对·O-2的清除作用最弱,但对清除ABTS·+、DPPH·、·OH均表现出较强的效果,龙眼核各萃取物抗氧化能力的结果为乙酸乙酯萃取物>氯仿萃取物>正丁醇萃取物>水层剩余物;除水层对沙门氏菌和大肠杆菌均无明显抑制作用外,4种萃取物对沙门氏菌、大肠杆菌、金黄色葡萄球菌均具有不同强度的抑制作用,其中乙酸乙酯层的抑菌活性最为突出。由结果可推断乙酸乙酯萃取物含有丰富的多酚类物质,可作为一种天然的抗氧化剂和抑菌剂,具有很大的药用价值和应用前景。Discussed the antioxidant and antimicrobial activities in vitro of different polarity parts in longan seeds, and effective parts were selected. The total polyphenol contents and the antioxidant ac- tivities of different polarity parts in 95 % ethanol extract from longan seeds were determined by Folin-Ciocalteu method and ABTS assay, DPPH assay, pyrogallol autoxidation assay and phenanthroline-Fe2＋ reaction system, respectively. Meanwhile, their antibacterial activi- ties were evaluated by oxford-cup method. The results showed thatthe ethyl acetate extract had the highest content of total polyphenols, which was （693.51±9.52） mg/g among the four extracts. The four extracts had a relatively weak scavenging effect on superoxide anion radicals but could strongly scavenge ABTS and DPPH and hydroxyl free radicals, The antioxidation activities in the order of ethyl acetate extract 〉 chloroform extract 〉 n-butanol extract ~ water residue. The four extracts had inhibitory effects of different intensity to Sal- monella, Escherichia coli, Staphylococcus aureus, and the ethyl ace- tate extract was especially outstanding, except for the water residue on the inhibition of Salmonella and Escherichia Coli had no obvious effect. According to the above results, the ethyl acetate extract of longan seeds could be regarded as a kind of good natural antioxidant and bacteriostatic because of it is rich in polyphenol compounds, and with a great pharmaceutical value and profound prospect.

关 键 词：龙眼核 萃取物 总酚 抑菌活性 抗氧化活性 

分 类 号：TS255.3[轻工技术与工程—农产品加工及贮藏工程] TS201.4[轻工技术与工程—食品科学与工程]