Chemical constituents from salt-processed Citri Reticulatae Semen and their antioxidant activities
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 IC50 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.
salt-processed Citri Reticulatae Semenchemical constituentsisolation and identificationantioxidant activities