Chitra Govindaraj, Balasubramani Govindasamy, Ramkumar Rajendiran, Sowmiya Rajamani, Perumal Pachiappan
Department of Biotechnology, Periyar University, Salem, Tamil Nadu, 636 011, India.
Parasitol Res. 2015 Apr;114(4):1407-15. doi: 10.1007/s00436-015-4320-7. Epub 2015 Jan 21.
Mosquitoes and mosquito-borne diseases are prone to raise health and economic impacts. Synthetic insecticide-based interventions are indeed in situations of epidemic outbreak and sudden increases of adult mosquitoes. Nanoparticles are being used in many commercial applications and were found that aqueous silver ions can be reduced by an aqueous extract of plant parts to generate extremely stable silver nanoparticles in water. Based on this, silver nanoparticles (SNPs) were synthesized using leaf aqueous extract (LAE) of Mukia maderaspatana. Further, the synthesized SNPs were characterized by UV-visible spectrum, which indicated a strong plasmon resonance at 427 nm. X-ray diffraction (XRD) analysis revealed the average crystalline size of the synthesized SNPs was approximately 64 nm by Debye-Scherrer formulae. Fourier transform infrared (FTIR) spectroscopy analysis revealed the presence of different functional groups like amines, halides, alkanes, alkynes, amides, and esters with respective stretches, which are responsible for the bio-reduction of silver ions. Field emission scanning electron microscopy (FESEM) depicted the spherical morphology of SNPs with size range of 13-34 nm. The larvicidal activity of LAE and SNPs exhibited an effective mortality to Aedes aegypti and Culex quinquefasciatus. The lethal concentration (LC50; LC90) of LAE and SNPs were found to be 0.506; 1.082, 0.392; 0.870 ppm and 0.211; 0.703, 0.094; 0.482 ppm, respectively on A. aegypti and C. quinquefasciatus. Thus, the synthesized SNPs have shown preponderant larvicidal activity, but further studies are needed to formulate the potential larvicidal agents.
蚊子和蚊媒疾病容易带来健康和经济影响。基于合成杀虫剂的干预措施确实适用于疫情爆发和成年蚊子数量突然增加的情况。纳米颗粒正被用于许多商业应用中,并且发现植物部分的水提取物可以还原水相银离子,从而在水中生成极其稳定的银纳米颗粒。基于此,利用马㼎儿的叶片水提取物(LAE)合成了银纳米颗粒(SNP)。此外,通过紫外可见光谱对合成的SNP进行了表征,结果表明在427nm处有强烈的等离子体共振。X射线衍射(XRD)分析表明,根据德拜-谢乐公式,合成的SNP的平均晶体尺寸约为64nm。傅里叶变换红外(FTIR)光谱分析揭示了存在不同的官能团,如胺、卤化物、烷烃、炔烃、酰胺和酯及其各自的伸缩振动,这些官能团负责银离子的生物还原。场发射扫描电子显微镜(FESEM)描绘了尺寸范围为13 - 34nm的SNP的球形形态。LAE和SNP的杀幼虫活性对埃及伊蚊和致倦库蚊表现出有效的死亡率。LAE和SNP对埃及伊蚊的致死浓度(LC50;LC90)分别为0.506;1.082ppm和0.392;0.870ppm,对致倦库蚊的致死浓度分别为0.211;0.703ppm和0.094;0.482ppm。因此,合成的SNP显示出显著的杀幼虫活性,但需要进一步研究来配制潜在的杀幼虫剂。