Green synthesis of Silver nanoparticle by Acanthus ilicifolius mangrove plant against Armigeressubalbatus and Aedesaegypti mosquito larvae

To identify the larvicidal activities of silver nanoparticles synthesized with Acanthus ilicifolius (A. ilicifolius) leaf extract against the larvae of Armigeressubalbatus and Aedesaegypti. In vitro larvicidal activities such as LC۵۰ and LC۹۰ were assessed for the A. subalbatus  and Ae.aegypti larval species. Further, characterization using different techniques such as UV, SEM,EDAX, XRD and FTIR analysis were carried out for the synthesized silver nanoparticles. The LC۵۰ value of the synthesized silver nanoparticle was determined as۰.۵۳۲ and ۰.۷۵۴mg/L for A. subalbatus and Ae. aegypti respectively. Further, the LC۹۰ values are also determined as ۲.۱۳ and ۵.۹۸mg/L for A. subalbatus and Ae. aegypti respectively. The synthesized silver nanoparticles have maximum absorption at ۴۲۰ nm with the average diameter ˃۱۸۰ nm. The Energy Dispersive Analysis of X-rays (EDAX) spectrum revealed the presence of silver metal in synthesized nanomaterials. The XRD data showed ۲θ intense values with various degrees such as ۳۷.۱۰°, ۴۷.۶۶°, ۶۳.۹۷° and ۷۰.۰۱°. The FTIR data showed prominent band at ۳,۴۰۰ cm-۱ and is assigned to the O–H stretching of H-bonded alcohols and phenols. The band at ۲,۹۲۵ cm-۱ is attributed to O–H stretching of carboxylic acids. The band at ۱,۶۱۶ cm-۱, corresponds to the N–H bending of primary amines. The bands at ۱,۴۴۴ and ۱,۵۲۱ cm-۱ are related to the C–C stretching of aromatic ring structure and the characteristic peak at ۱,۳۶۰ cm-۱corresponds to the C–N stretching of aromatic amine group whereas in the region of ۱,۱۵۰–۱,۲۸۲ cm-۱ are corresponding to the C–C stretching alcohols, carboxylic acids, ethers and esters. The significance of above results clearly indicate that no toxicity developed biosynthesis of silver nanoparticles with leaf aqueous extract of A. ilicifolius  provides potential source for the larvicidal activity against mosquito borne diseases.

Keywords:

Acanthus ilicifolius , Biosynthesis , Dengue , LC۵۰ , LC۹۰ , Mangrove , Silver nanoparticles