Study On The Molluscicide Activity Of The Extract Of Schima Superba Against Pomacea Canaliculata And The Identification Of Active Substance

In this research, we take Schima superba (Theaceae) as the research object, and study toxic activity of Schima superba (Schima superba) against Pomacea canaliculata and active substance. The main research results are as follows:1. We analyzed the efficacy of methanol, ethyl acetate and petroleum ether solvents on the molluscicide activity of the extracts from stem bark and leaf of Schima superba,. The results revealed that stem bark extracts with methanol, ethyl acetate and petroleum ether solvents showed significant molluscicidal activity against Pomacea canaliculata. The best effect was the methanol extracts of Schima superba stem bark, the corrected mortality of which was 95.00% at 48 h under the concentration 20.00?g/ml.2. We further measured the molluscicide activity of the methanol extracts of Schima superba stem bark against Pomacea canaliculata with different size of screw body under varied temperature. The value of LC50 on Pomacea canaliculata with 25�2mm in diameter was 31.45 ?g/ml,19.07 ug/ml and 18.79 ?g/ml under 15 ?,20 ? and 25 ? temperature conditions at 24h, respectively. With treated 48 h, the value of LC50 was 14.70 ?g/ml,14.37 ?g/ml and 8.83?g/ml under three temperature conditions. With treated 72 h, the value of LC50 was 12.25 ?g/ml,11.31 ?g/ml,8.33 ?g/ml, respectively. These results indicated that the molluscicide activity of methanol extract from stem bark on became more obvious as the temperature rose. The results showed that under 15�2mm,25�2mm,35�2mm size conditions while the room temperature was 25 ?, the value of LC50 on apple snails was 16.60?g/ml,18.56?g/ml, 19.41?g/ml at 24h, respectively. With treaded 48h, the value of LC50 was 9.57?g/ml, 9.90?g/ml.11.18?g/ml under different size of screw body. With treaded 72h, the value of LC50 was 9.43?g/ml,9.48?g/ml,10.06?g/ml, respectively. It indicated that there was no connection between the efficacy of methanol extract stem bark on apple snails and body size.3. We analyzed the molluscicide activity of 10% schima superba bark extract micro emulsion by spraying and immersing. It was significant different that the control efficiency under 200?g/ml of 10% schima superba bark extract micro emulsion was 23.33%,31.67%,33.33% and 41.67% at Id,3d,5d and 7d, respectively, compared with niclosamide under 2?g/ml by spraying.It was not significant different that the control efficiency under 8?g/ml of 10% schima superba bark extract micro emulsion was 61.11%,86.67%,92.22% and 93.33% at Id,3d,5d and 7d, respectively, compared with niclosamide under 2?g/ml by immersing. It indicated that the effect of immersing of 10% schima superba bark extract micro emulsion was better than the effect of spraying.4. We adopted macroporous resin, C18 gel column chromatography and high performance liquid chromatography preparation combined with active tracking to separate, purify and identify the active ingredient of the methanol extract of Superba bark.Eventually, we won four compounds, they were Sasanquasaponins?, MaetenosideB, ProcyanidinB2, (-)-Epicatechin.Sasanquasaponins ?, Maetenoside B two compounds showed obvious poison activity on apple snails among them.