Research On The Molluscicidal Activity Of Extracts From Three Plants (such As Jatropha Carcas L.) And The Molluscicidal Mechanism Of Shells In J. Curcas

Jatropha carcas L.is one of bio-energy plant,and the whole plant is poisonous.A few of semi-wild and large number of cultivated species are distributed in southwest China.Shells（peels）of J.curcas,fruit（SJF）is the residue of processing J.curcas seed oil.Nandina domestica Thunb.is a widely implicated as an ornamental plant in cities along the Yangtze river in China.There are almost no diseases and insects in N.domestica.Juglans regia L.is a good economic tree species suitable for planting in most parts of China.Shells（peels）of J.curcas,fruit（SJF）,J.regia fruit peel,and N.domestica leaves are always discarded at will.A large number of N.domestica fruits are easily harvest.P.canaliculata is an invasive aquatic snail that seriously endangers farmland ecosystem.Angiostrongylus cantonensis is parasitic on P.canaliculata.Based on the utilization of plant resources and the reuse of forestry wastes,firstly,molluscicidal effects of the extracts from SJF,J.regia peel,N.domestica fruit,and N.domestica leaf were evaluated against P.canaliculata.the results of simulated test（pot experiment）were to further select suitable molluscicide plant materials.Thirdly,molluscicidal active components of J.curcas shells were isolated and identified.The aim of this study was to provide theoretical basis for the research and development of molluscicidal active components from J.curcas shells.1.SJF is a better molluscicidal plant than the fruit and leaf of N.domestica.J.regia fruit peel is no value for controlling P.canaliculata.200 mg L^-1dichloromethane extract（DE）from SJF could not only effectively prevent the P.canaliculata from eating rice seedlings,but also had no significant effect on the normal growth of rice seedlings.The suitable harvest time of N.domestica fruit is 3-5 month after flowering（MAF）as a potential plant molluscicidal material.Compared with the clear water control group（P.canaliculata lays eggs）,P.canaliculata did not lay eggs after being treated with extracts of SJF,N.domestica fruit and N.domestica leaf in mating season.Both DE of SJF and extract of ethanol soxhelt（SE）from N.domestica fruit had killing effect on Pseudoregma bambusicola.SE of N.domestica leaf had better inhibitory effect on Staphylococcus aureus and Escherichia coli than SE of N.domestica fruit.2.On the basis of the separation and identification of active constituents from the SJF by predecessors,molluscicidal compound purified from J.curcas shells（SJFM）was purrified from J.curcas shells.Meanwhile,the results showed that the SJFM contains three monomer compounds:octadecanoic acid,oleic acid,Hexadecanoic acid.The fourth group（Petroleum ether-acetone,7:1）contains Hexadecane andβ-sitosterol.3.The mean Lethal Concentration 50(LC₅₀)of was 111.619 mg L^-1.At 96 h,the contents of total protein（TP）,glycogen contents,cholinesterase（Ch E）,cytochrome P450（CYP450）in treatment 89.30 mg L^-1SJFM decreased significantly than that in treatment 0mg L^-1SJFM.The hepatopancreas cell structure of P.canaliculata treated with 89.30 mg L^-1SJFM was significantly damaged,such as disruption of nuclear membrane,swelling mitochondria,dilatation of nuclear reticulum,and vacuolization mitochondria.The results showed that SJFM was seriously damage the normal metabolism of P.canaliculata.4.The CYP450 enzyme content was respectively positively correlated with the relative expression of cytochrome P3A-like protein（CYP3A-like protein）（r=）and cytochrome P4P1（CYP4P1）in the hepatopancreas of P.canaliculata.The values of correlation coefficients were 0.437 and 0.455,respectively.The correlations were extremely significant（p<0.05）.It is presumed that the change of CYP450 enzyme content is obviously regulated by the expression of CYP4P1 and CYP3A-like protein in hepatopancreas of P.canaliculata.5.The concentration of SJFM was significantly correlated with the relative expression of CYP4P1 mRNA（r=-0.502）.The concentration of SJFM significantly inhibited the expression of CYP4P1.It is speculated that CYP4P1 mRNA may be a target gene of SJFM acting on the hepatopancreas of P.canaliculata.In conclusion,SJF is a better molluscicidal plant than the fruit and leaf of N.domestica.In the later period of molluscicidal experiments,SJFM was not only to decrease content of CYP450,but also significantly inhibited the expression of CYP4P1.This is maybe one way of SJFM for affecting CYP450 activity of hepatopancreas tissue in P.canaliculata.It inferred that CYP4P1 may be a target gene of SJFM acting on the hepatopancreas of P.canaliculata.