以尖膀胱螺作为试验动物,研究毒死蜱对尖膀胱螺抗氧化系统、乙酰胆碱酯酶和一氧化氮合酶的影响。通过预试验获得尖膀胱螺72 h LC50为243μg/L,推算的安全浓度为16μg/L,正式试验以16和121.5μg/L浓度组分别暴露尖膀胱螺96 h。在第24、48...以尖膀胱螺作为试验动物,研究毒死蜱对尖膀胱螺抗氧化系统、乙酰胆碱酯酶和一氧化氮合酶的影响。通过预试验获得尖膀胱螺72 h LC50为243μg/L,推算的安全浓度为16μg/L,正式试验以16和121.5μg/L浓度组分别暴露尖膀胱螺96 h。在第24、48和96 h分别取材,测定尖膀胱螺体内超氧化物歧化酶(SOD)、乙酰胆碱酯酶(AChE)、一氧化氮合酶(NOS)的活性和丙二醛(MDA)含量变化情况。结果显示,在推算的安全浓度(16μg/L)暴露后,尖膀胱螺体内MDA含量和NOS活性在各时间段变化均不明显,而SOD和AChE活性在96 h被抑制;在高浓度组(121.5μg/L),尖膀胱螺SOD呈现先上升后下降后又有所回升的趋势,MDA水平持续上升,NOS水平被显著性诱导,AChE活性则被显著性抑制,且在48 h时抑制作用最强。试验结果表明毒死蜱对尖膀胱螺抗氧化系统和神经中枢均产生一定的影响,提示尖膀胱螺可作为毒死蜱毒理学试验模型动物,同时MDA和AChE可作为毒死蜱毒性的生物标记物。展开更多
Objective:To evaluate the efficacy of Alstonia congensis green-synthesized nanoparticles as a molluscicide against snail hosts of trematodes.Methods:The ethanolic leaf extract of Alstonia congensis was used to synthes...Objective:To evaluate the efficacy of Alstonia congensis green-synthesized nanoparticles as a molluscicide against snail hosts of trematodes.Methods:The ethanolic leaf extract of Alstonia congensis was used to synthesize silver nanoparticles.The formulation was characterized by Fourier transform infrared spectroscopy,X-ray powder diffraction,and scanning electron microscope/energy-dispersed X-ray.The ovicidal and molluscicidal activities of the Alstonia congensis extract and its nanoparticles were tested against Physa acuta and Bulinus forskalii at different concentrations.Results:The green-synthesized nanoparticles inhibited embryonic development within the egg masses of the two snails in all the tested concentrations.Alstonia congensis extract did not show molluscicidal properties against adult Physa acuta but showed a very weak activity against Bulinus forskalii.Moreover,the synthesized nanoparticles showed significantly high molluscicidal activity against adult snails within 5-40 min of exposure in a concentration-dependent manner(P<0.05).Conclusions:The Alstonia congensis-based nanoparticles show molluscicidal activities against adults and embryos of Physa acuta and Bulinus forskalii,and can be further explored as a potent molluscicide for the control of intermediate host of trematode parasites.展开更多
进行了百草枯(paraquat)对尖膀胱螺(Physa acuta)成体及其胚胎各发育期(囊胚期、担轮幼虫期、面盘幼虫期和仔螺孵化期)的急性毒性实验。结果表明,百草枯对尖膀胱螺成体72 h和96 h LC50分别为2.53 mg/L和1.41 mg/L;对其胚胎各个时期72 h ...进行了百草枯(paraquat)对尖膀胱螺(Physa acuta)成体及其胚胎各发育期(囊胚期、担轮幼虫期、面盘幼虫期和仔螺孵化期)的急性毒性实验。结果表明,百草枯对尖膀胱螺成体72 h和96 h LC50分别为2.53 mg/L和1.41 mg/L;对其胚胎各个时期72 h LC50分别为2.63、2.45、2.07、1.53 mg/L;96 h LC50分别为1.63、1.41、1.25、0.60 mg/L。百草枯对尖膀胱螺成体及其胚胎各发育期均有一定的毒性效应,胚胎比成体敏感,对胚胎各发育期的毒性也不同;随着染毒时间的延长,胚胎敏感性逐渐增强。研究表明,当百草枯进入水生态系统时,有可能对尖膀胱螺及其种群稳定造成影响。展开更多
文摘Objective:To evaluate the efficacy of Alstonia congensis green-synthesized nanoparticles as a molluscicide against snail hosts of trematodes.Methods:The ethanolic leaf extract of Alstonia congensis was used to synthesize silver nanoparticles.The formulation was characterized by Fourier transform infrared spectroscopy,X-ray powder diffraction,and scanning electron microscope/energy-dispersed X-ray.The ovicidal and molluscicidal activities of the Alstonia congensis extract and its nanoparticles were tested against Physa acuta and Bulinus forskalii at different concentrations.Results:The green-synthesized nanoparticles inhibited embryonic development within the egg masses of the two snails in all the tested concentrations.Alstonia congensis extract did not show molluscicidal properties against adult Physa acuta but showed a very weak activity against Bulinus forskalii.Moreover,the synthesized nanoparticles showed significantly high molluscicidal activity against adult snails within 5-40 min of exposure in a concentration-dependent manner(P<0.05).Conclusions:The Alstonia congensis-based nanoparticles show molluscicidal activities against adults and embryos of Physa acuta and Bulinus forskalii,and can be further explored as a potent molluscicide for the control of intermediate host of trematode parasites.
文摘进行了百草枯(paraquat)对尖膀胱螺(Physa acuta)成体及其胚胎各发育期(囊胚期、担轮幼虫期、面盘幼虫期和仔螺孵化期)的急性毒性实验。结果表明,百草枯对尖膀胱螺成体72 h和96 h LC50分别为2.53 mg/L和1.41 mg/L;对其胚胎各个时期72 h LC50分别为2.63、2.45、2.07、1.53 mg/L;96 h LC50分别为1.63、1.41、1.25、0.60 mg/L。百草枯对尖膀胱螺成体及其胚胎各发育期均有一定的毒性效应,胚胎比成体敏感,对胚胎各发育期的毒性也不同;随着染毒时间的延长,胚胎敏感性逐渐增强。研究表明,当百草枯进入水生态系统时,有可能对尖膀胱螺及其种群稳定造成影响。