Study On The Exogenous Free Radical Inhibitor Active Components Of Two Kinds Of Saxifraga Plant

Saxifraga atrata and Saxifraga sinomontana are perennial herb of the Saxifraga genus(Saxifragaceae family),mainly distributed in Qinghai,Gansu,Tibet,Sichuan,Yunnan and other places,flowers are used as medicine in Traditional Chinese Medicine(TCM)and Traditional Tibetan Medicine(TTM).S.atrata exhibits the effect of relieving cough,lowering blood pressure,and nourishing.It could be used for the treatment of pneumonia,gonorrhea,lymphatic tuberculosis,uterine disease and so on.S.sinomontana is used to treat liver and gallbladder damp-heat,spleen and stomach damp-heat,acute purulent infection and skin ulcer,etc.It can also be used to treat headaches caused by hyperactivity of liver yang,and it can also be used for neuralgia.Based on the literature review,it is found that other Saxifraga species contain a large number of exogenous free radical(Ex FR)inhibitors,but there is a lack of systematic research reporting on the exogenous free radical inhibitors originated from S.atrata and S.sinomontana.Therefore,this paper mainly studies the exogenous free radical inhibitors from S.atrata and S.sinomontana.In this study,S.atrata and S.sinomontana were used as the research objects.An online HPLC-DPPH activity screening method was developed to screen and study the active ingredients that inhibit exogenous free radicals.Combined with the medium and high-pressure preparation liquid phase analysis and separation methods,a rapid separation analysis technology integrating high-throughput analysis,target identification and high-efficiency preparation has been established;this research has achieved the following main results:(1)An online HPLC-DPPH activity screening method was established,and exogenous free radical inhibitory active ingredients in S.atrata and S.sinomontana can be detected online in real time through the post-column derivatization system.(2)Through the medium and high-pressure preparation liquid phase chromatography combined with two-dimensional separation and purification method,i.e.hydrophilic/reversed phase separation mode and reversed phase/reversed phase separation mode,the active ingredients in S.atrata and S.sinomontana can be separated by targeted separation.The purity of the compounds is greater than 95%.(3)A total of 15 high-purity compounds were isolated and identified;11compounds were identified from S.atrata for the first time,of which 6 compounds are exogenous free radical inhibitory active ingredients: Ethyl gallate(1),11-OGalloylbergenin(2),Rutin(3),Isoquercitrin(4),(-)-4-O-(E)-Caffeoyl-L-threonic acid(5),Adenosine(6).The remaining 5 compounds are: 11-O-(4-O-methylgalloyl)-bergenin(7),Kaempferol-3-O-rutinoside(8),Kaempferol-3-O-β-D-glucoside(9),Uridine(10),Bergenin(11).Four exogenous free radical inhibitory active ingredients were identified from S.sinomontana,including two new diarylnonanoid compounds:4-hydroxy-2-methoxyphenol-1-O-β-D-(6’-O-galloyl)glucopyranoside(12),3,4,5-trime thoxyphenyl-(6’-O-galloyl)-O-β-D-glucopyranoside(13),(3E)-1,9-Bis(3,4-dihydroxy phenyl)-7-methoxy-3-nonene-5-one(14*),(3E,6E)-1,9-bis(3,4-dihydroxyphenyl)-3,6-nonadiene-5-one(15*).