泽泻原三萜、降三萜和倍半萜的分离及其抗炎活性研究

Isolation of Protostane Triterpenoids,Nor-triterpenoids and Sesquiterpenes from Rhizoma Alismatis and their Anti-inflammatory Activities Research

目的对泽泻中原三萜、降三萜和倍半萜化学成分分离和鉴定及其抗炎活性进行研究;方法采用硅胶柱色谱、凝胶柱色谱、高速逆流色谱、中压制备色谱和半制备色谱法对泽泻中各类化合物进行分离,利用1H和13C NMR对分离化合物进行结构鉴定;通过测定各单体对LPS(1μg·mL^(-1))诱导Caco-2细胞中NO生成的抑制作用评价其抗炎活性。结果从泽泻中分离得到19个化合物,包括8个原三萜类成分:alisol A 23 acetate(1),alisol G(2),16-oxo-11-anhydroalisol A(3),16-oxo-11-anhydroalisol A 24 acetate(4),alisoma A(5),alisoma B(6),alismanol J(7),alismanol B(8);1个降三萜类成分:17-nor-protostane(9);9个倍半萜类成分:orientalol L(10),orientalol M(11),orientalol N(12),orientalol O(13),orientalol P(14),alismanoid A(15),heyneanones D(16),leptocladol B(17),chabrolidione B(18);1个木脂素类成分:pnoresinol(19)。原三萜类成分均具有显著的抑制活性,化合物1-8的IC50分别为2.1、0.9、7.3、10.0、11.0、16.0、13.5和10.5μmol·mL^(-1),降三萜及倍半萜活性较弱,化合物10、11、13、15、16和17的IC50分别为24.0、26.2、30.6、15.7、17.2和15.2μmol·mL^(-1)。结论化合物16、17、18和19为该植物首次分离得到。首次报道了倍半萜类成分对LPS诱导Caco-2细胞中NO生成的抑制作用,其中alisol A 23 acetate和alisol G的抑制活性最强。

Objective To isolate protostane triterpenoids,nor-triterpenoids and sesquiterpenes from Rhizoma Alismatis and evaluate their anti-inflammatory activities.Methods The silica gel chromatography,sephadex chromatography,high-speed countercurrent chromatography,medium pressure column chromatography,and semi-preparative HPLC were employed to isolate compounds,whose chemical structures were identified by1H and13C NMR.All isolates were evaluated for their inhibitory effects on LPS(1μg·mL^(-1))induced NO production in Caco-2 cells.Results A total of 19compounds were isolated and identified including eight protostane triterpenoids:alisol A 23 acetate(1),alisol G(2),16-oxo-11-anhydroalisol A(3),16-oxo-11-anhydroalisol A 24 acetate(4),alisoma A(5),alisoma B(6),alismanol J(7),alismanol B(8);one nor-triterpenoid:17-nor-protostane(9);nine sesquiterpenes:orientalol L(10),orientalol M(11),orientalol N(12),orientalol O(13),orientalol P(14),alismanoid A(15),heyneanones D(16),leptocladol B(17),chabrolidione B(18)and one lignin:pnoresinol(19).All the protostane triterpenoids(1-8)showed remarkable activities with IC50values of 2.1,0.9,7.3,10.0,11.0,16.0,13.5 and 10.5μmol·mL^(-1),respectively,and the nor-triterpenoid and sesquiterpenes compounds,on the contrary,had lower activities with IC50of 24.0,26.2,30.6,15.7,17.2 and 15.2μmol·mL^(-1)for compound 10,11,13,15,16 and 17,respectively.Conclusion Compounds 16,17,18 and 19 are isolated from Alismatis Rhizoma for the first time.The sesquiterpenes are evaluated for their inhibitory effects on LPS-induced NO production in Caco-2 cells for the first time,among which alisol A 23 acetate and alisol G exhibited the strongest inhibitory activities.