The scientific community is search in for new methods for the synthesis of metallic nanoparticles. Green synthesis has now become a vast developing area of new research groups. Here we report a green method to the synthesis of silver nanoparticles (AgNPs) using the different parts of Vishanika or Indian screw tree, an ayurvedic medicinal tree. This is nontoxic, eco-friendly and low cost method. The reduction and stabilization capability of the plant extracts of different parts are described. The size and structure of the silver can be characterized by varying the plant parts of the vishanika. The biosynthesized nanoparticles are characterized by using UV-VIS spectroscopy, TEM, XRD, DLS and FTIR. The size and extract dependent catalytic activity of the biosynthesized nanoparticles is established in the degradation of organic dyes.plant products represent excellent platforms for this purpose [6][7][8]13]. The compounds present in plants that have different potential biological activities; phytochemicals are important natural resource for the synthesis of metal nanoparticles. They play important roles in both stabilization and reduction of nanoparticles. The focus of the present work is to apply the accurate principles of green chemistry for the synthesis of silver nanoparticles by using stem bark, root and leaf of Helicteres isora extracts as stand-alone reducing and capping agent. H. isora plant extracts possess anticancer properties [14]. Usually, the bark and root juice were used against diabetes and emphysema. In traditional medicine, the bark and root juice is claimed to be useful in snake bite, diabetes, blood disorder, cough, colic, diarrhoea, astringent, etc., [15], expectorant and astringent [16], hypolipidemic [17], antihyperglycemic activity and glibenclamide [18]. In the present study, we have investigated the extracts and size dependent catalytic degradation of organic dyes-methyl violet, safranin, eosin methylene blue and methyl orange by in the presence of silver colloids. Materials and MethodsSilver nitrate (99.99%), methyl violet, safranin, eosin methylene blue and methyl orange, were purchased from sigma Aldrich. All glassware's were cleaned with sterile distilled water and rinsed with deionized water. Preparation of extractDifferent parts of (stem bark, root and leaf) H. isora were collected from Western Ghats of Tamil Nadu, washed with sterile distilled water and dried, then make it powder. 1 g of each explants powder was mixed with 100 mL of water and kept on orbital shaker at 120 rpm for 12 h. After that, the extracts were filtered with filter paper and stored at 4 0 C in refrigerator until further use. Journal of Bior emediation & Biodegradation Synthesis of silver nanoparticlesSilver nanoparticles (stem bark (S), root (R) and leaf (L)) have been synthesized by Bhakya et al. [19] method with slight modification. The formation of AgNPs is indicated by the appearance of dark brown color within 5 min. CharacterizationUV-visible spectra analysis was performed for all samples and the abs...