Study On The Active Constituents Of Macroalgae Chondrus Ocellatus Holmes

In this thesis,the Chondrus ocellatus Holmes was used as raw material to study its chemical composition and biological activity such as free radical scavenging activity,anti-angiotensin I converting enzyme activity and proline endopeptidase inhibitory activity.Its alcohol extracts was extracted from Chondrus ocellatus Holmes and successively extracted with petroleum ether,ethyl acetate and n-butane to obtain three different extracts.12 compounds were isolated by a variety of chromatographic separation and purification methods.Five of them were identified by physical and chemical constant measurement and spectral data analysis.They were cholesterol,ocellatus glycolipid A,ocellatus glycolipid B,ocellatus glycolipid C and 3'-(1-butylphosphoryl)adenosine.Among them,ocellatus glycolipid A,ocellatus glycolipid B,ocellatus glycolipid C and 3'-(1-butylphosphoryl)adenosine were isolated from Chondrus ocellatus for the first time.The extraction process of polysaccharide from Chondrus ocellatus Holmes was optimized.The four factors of ratio of raw material solution(A),flash extraction time(B),hot reflux extraction time(C)and extraction temperature(D)were investigated.The suitable conditions for preparing the polysaccharide from Chondrus ocellatus Holmes were as follows: extraction time 2.5 h,extraction temperature 95?,flash extraction tim 4 min,and the ratio of material to liquid was 1:25.The crude polysaccharides were fractionated by 30%,50%,and 80% ethanol,and the three different kinds of polysaccharides were purified by a gel column,and the sulfate group content was measured as 45.87%,26.78% and 31.94%?The free radical scavenging activity,angiotensin I converting enzyme(ACE)inhibitory activity,proline endopeptidase(PEP)inhibitory activity and anti-tumor activity were determined on the alcohol extract,petroleum ether extract,ethyl acetate extract and n-butane extract in vitro.It showed a certain scavenging activity on DPPH free radicals at concentrations of 0.01,0.1,and 1 mg/m L,respectively and the activity is dose-dependent with concentration.Yet the scavenging activity of ·OH radicals and ·O2 ? free radicals was not obvious.The extracts showed no significant inhibitory activity on ACE.The water extract showed a certain inhibition on PEP and the IC50 value of water extract inhibition was 25.24 ?g/m L.There showed no significant inhibition of He La,MCF-7 and Hep-G2.on the extracts from Chondrus ocellatusIn addition,the alcohol extracts and water extracts from various large seaweeds was studied on ACE and PEP inhibitory activity in vitro.The experimental results showed that the alcohol extracts of four species of seaweeds,such as the Gymnogongrus flabelliformis Harv,the Grateloupia livida(Harv).Yamada,the Coralline algae,and the Ulva pertusa had higher ACE inhibitory activity,and the IC50 values were 20.90,40.56,74.93,and 124.18 mg/m L,respectively.In the water extracts,the ACE inhibitory activity was higher on the extracts of Gymnogongrus flabelliformis Harv,Entermorpha intestinalis(L.)Link,D.dichotoma(Huds.)Lamx,and S.siliquastrum(Turn.)Ag.,and the IC50 values were 64.94,58.58,23.26,and 67.88 mg/m L,respectively.Five kinds of alcohol extracts from seaweeds,such as Dictyoteris divaricata,S.siliquastrum(Turn.)Ag.,Rhodomela Confervoides,Grateloupia livida(Harv).Yamada and Sphaerotrichia firma,had significant inhibitory activity on PEP.The results showed that the extracts of the activity was dose dependent,with IC50 values of 147.64,36.09,123.88,135.36,and 77.38 ug/m L,respectively.The IC50 values of the water layer of Dictyoteris divaricata,Sphaerotrichia firma,Sargassum miyabei,S.siliquastrum(Turn.)Ag.,Rhodomela Confervoides and Hizikia fusifarme were 6.53,11.27,17.34,19.40,19.00,32.71 ?g/m L,respectively.The extracts of Gymnogongrus flabelliformis Harv,Grateloupia livida(Harv).Yamada,Coralline algae and Sargassum thunbergii had some inhibitory activity on PEP,and the IC50 values were 132.37,103.36,147.52,and 135.70 ?g/m L,respectively.This thsis provides a theoretical basis for the development and utilization of Chondrus ocellatus Holmes and large seaweed resources.