Studies On Active Components From Radix Angelicae Pubescentis Against Fish Dactylogyrus

Dactylogyriasis is one of the serious parasitosis in aquaculture.It can occur in most of province of our nation,and its harm is becoming more and more strongly.At present, medication is the most effective way in fishery,but study and production of fish medicines mainly relay on chemotherapeutants applied in other fields such as human medicines,animal medicines and a part of pesticides.A lot of chemotherapeutants,chronically used,have caused environmental pollution,drug residue,drug fastness for our national aquatic productions. Therefore,it is necessary to find a new Botanical Insecticide which is non-pollution to environment and easy to degradation.It is a fast and economical way to optimize exploitage to plant resources to find out new drugs against aquatic bacteria and parasite from plants.In this experiment,screening of active plants,screening of active part of parasiticidally active plants,isolation and tracing of active compounds,analysis for spectroscopy,elucidation for chemical structure were conducted in this text.The results are obtained as follows:1.Screening of parasiticidally active plants:According to the pharmacodynamic test,the parasiticidal activity of extractions of 20 plants on D.intermedius was determined.From the results,the maximum killing rate of extractions of variety plants on D.intermedius in 48 hours was:Radix Angelicae Pubescentis attained100%;Pyrethrum cinerariifolium attained 90%;Radix Polygalae,Indian Stringbush Root and Celastrus angulatus attained 80%;Radix Archangeliae Decurrentis,Herba Lobeliae Chinensis,Cephaelis ipecacuanha and Herba Potentillae Chinensis attained 50%;Nandina domestica,Corydalis yanhus,Veratrumnigrum L, Gelsemium elegans,Herba Chelidonii and Eomecon chionantha Hance attained 20%-30%;the other tested samples had not shown obvious killing activities in experimental concentration of 1000mg.L^-1.The optimization killing concentration:Indian Stringbush Root was 30 mg.L^-1;Radix Angelicae Pubescentis was 120 mg.L^-1;Herba Chelidonii was 150 mg.L^-1;Radix Archangeliae Decurrentis was 200 mg.L^-1;Pyrethrum cinerariifolium was 240 mg.L^-1;Radix Polygalae was 350 mg.L^-1;Veratrumnigrum L was 400 mg.L^-1;Celastrus angulatus was 500 mg.L^-1;Corydalis yanhus was 600 mg.L^-1;Nandina domestica was 700 mg.L^-1;Eomecon chionantha Hance,Gelsemium elegans,Herba Lobeliae Chinensis and Cephaelis ipecacuanha were 800 mg.L^-1.In tested concentration,the palnts which can lead Carassius auratus to death were listed in table2-2.Among the total,Platycarya strobilacea,Fructrs Trichosanthis,Gelsemium elegans,Herba Lobeliae Chinensis,Cephaelis ipecacuanha,Herba Potentillae Chinensis can not lead Carassius auratus to death in experimental concentration of 1000mg.L^-1.2.Study of parasiticidally active part of Radix Angelicae Pubescentis:Radix Angelicae Pubescentis was respectively distilled by ethanol,acetone,petroleum ether and ethyl acetate, then activity of each extraction was measured.The results shew that when parasiticidal concentration of ethanol extraction was 100%,its optimal concentration of killing Dactylogyrus was 120 mg.L^-1(according to raw-herb count);optimal concentration of acetone was 70 mg.L^-1(according to raw-herb count),the killing rate was 72.0%;optimal concentration of petroleum ether was 300 mg.L^-1(according to raw-herb count),the killing rate was 64.8%;optimal concentration of ethyl acetate was 100mg.L^-1(according to raw-herb count),the killing rate was only 49.1%.3.Isolation,activity tracing and identification of active components from Radix Angelicae Pubescentis:through measurement of activity to different extractions,the extractions of ethanol was demonstrated to be the most effective part against Dactylogyrus. The ethanol extraction was separated into 16 parts(A-P) by silica gel column chromatography with gradually increasing polarity of petroleum ether:ethyl acetate(40:1,30:1,20:1, 10:1,5:1,2:1,1:1,0:1) and ethyl acetate:methanol(100:1,50:1,20:1,10:1,5:1,3:1,2:1,1:1,0:1 and water).According to activity test,the part F and K were demonstrated to be the most effective part and F was pure substance and simple point.The part K was isolated by silica gel column chromatography with gradually increasing polarity of chloroform:methanol(50:1,25:1, 10:1,9:1,8:1,7:1,5:1,3:1,2:1,1:1,methanol and water),11 parts were isolated from Part K. According to activity test,only part K₁ was effective part.The part K₁ was further isolated by silica gel column chromatography with gradually increasing polarityof petroleum ether:ethyl acetate(1:0,50:1,20:1,10:1,5:1,2:1,1:1,0:1,methanol),6 parts were isolated from Part K₁. According to activity test,the part K_1-1and K_1-2 was effective part,and part K_1-1 was oily ingredient.The part K_1-2 was further isolated by silica gel column chromatography with gradually increasing polarityof petroleum ether:chloroform(6:4,6:5,6:6,6:7,chloroform),4 parts were isolated from Part K_1-2.According to activity test,the part K_1-2-3 was effective part, and it was pure substance and simple point.From the results of the activity test of F and K_1-2-3, the maximum killing rate of extractions of variety plants on Dactylogyrus in 48 hours was:the concentration of F was 1.6 mg.L^-1;the killing rate of K_1-2-3 was 74.4%in the concentration of 5 mg.L^-1;the killing rate of K_1-1 was 51.9%in the concentration of 20 mg.L^-1. Based on the data of IR,EI-MS,¹H-NMR,¹³C-NMR,HPLC and GC-MS,F was identified as osthol,K_1-2-3was identified as scopletin isopimpinellin.,K_1-1 was identified as oily ingredient.