盐橘核化学成分及其抗氧化活性

Chemical constituents from salt⁃processed Citri Reticulatae Semen and their antioxidant activities

目的研究橘核CitriReticulataeSemen盐炙品化学成分及其抗氧化活性。方法盐炙橘核85%乙醇提取物采用硅胶、D101大孔吸附树脂、MCI、ODS、SephadexLH-20、半制备型HPLC进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构。采用DPPH、ABTS+自由基清除法对橘核及其盐炙品乙醇提取物、所得化合物进行抗氧化活性评价。结果从中分离得到16个化合物,分别鉴定为柠檬苦素(1)、黄柏酮(2)、诺米林(3)、去乙酰基诺米林(4)、山柰酚(5)、川陈皮素(6)、香叶木素(7)、异樱花素(8)、橙皮素(9)、表儿茶素(10)、trans-p-menthane-1α,2β,8-triol(11)、白当归素(12)、香草醛(13)、反式对羟基肉桂酸(14)、4-[(1-ethoxy-2-hydroxy)ethyl]phenol(15)、儿茶酚(16)。化合物10显示出较强的DPPH自由基清除活性,其IC50值为(0.015±0.001)μmol/mL,以及较强的ABTS+自由基清除活性,其IC_(50)值为(0.010±0.005)μmol/mL。结论化合物8、11、15~16为首次从柑橘属植物中分离得到,5、12、14为首次从橘核中分离得到。化合物10具有较强的抗氧化活性。橘核经盐炙后,其乙醇提取物抗氧化活性增强。

AIM To study the chemical constituents from salt-processed Citri Reticulatae Semen and their antioxidant activities.METHODS The 85%ethanol extract from salt-processed Citri Reticulatae Semen was isolated and purified by silica gel,D101 macroporous resins,MCI,ODS,Sephadex LH-20 and semi-prepative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.Their antioxidant activities in vitro of the ethanol extract of Citri Reticulatae Semen,salt-processed Citri Reticulatae Semen and all the obtained compounds were evaluated by DPPH and ABTS+assay.RESULTS Sixteen compounds were isolated and identified as limonin(1),obacunone(2),nomilin(3),deacetyl nomilin(4),kaempferol(5),nobiletin(6),diosmetin(7),isosakuranetin(8),hesperetin(9),epicatechin(10),trans-p-menthane-1α,2β,8-triol(11),byakangelicin(12),vanillin(13),p-coumaric acid(14),4-[(1-ethoxy-2-hydroxy)ethyl]phenol(15),catechol(16).Compound 10 showed strong DPPH free radical scavenging activity,with an IC50 value of(0.015±0.001)μmol/mL,and strong ABTS+radical scavenging activity,with an IC_(50) value of(0.010±0.005)μmol/mL.CONCLUSION Compounds 8,11,15-16 are isolated from genus Citrus for the first time,5,12,14 are obtained from Citri Reticulatae Semen for the first time.Compound 10 shows obvious antioxidant activities.After salt roasting,the antioxidant activity of the ethanol extract of Citri Reticulatae Semen is enhanced.