Silver Nanoparticle Biosynthesis and Antibacterial Activity of Aqueous Leaf Extract of Lagerstroemia speciosa Vijayaraghavalu Sai Saraswathi* 1 , Dhakshanamurthy Thirumalai 1 , Himaja Malipeddi 1 , Indhra Viswambaran Asharani 1 , Kokati Venkata Bhaskar Rao 2 and Satyanarayana Ravi Sathish Kumar 2 1 Chemistry Department, School of Advanced Science, VIT University, Vellore, INDIA. 2 Biotechnology Department, School of Bio Sciences and Technology, VIT University, Vellore, INDIA Received on 20 – 04 - 2013 Revised on 27 – 05- 2013 Accepted on 23– 06 – 2013 ABSTRACT Plant based biosynthesis of nanoparticle has proved to be an effective and alternate method for the novel production of nanoparticles. The plant sources, especially leaves are valuable for the generation of silver nanoparticles (Ag NPs).The present investigation deals about the green method biosynthesis of AgNPs, from the aqueous decoction extract of dried leaves of lagerstroemia speciosa with 0.0101mg of AgNo 3 stirred at 75°C under dark condition. The silver nanoparticles formation was identified visually and characterized by UV-Visible spectrophotometry, TEM (Transmission Electron Microscope) analysis. The particle shape was found to be spherical in nature. The silver nanoparticle (100μl) showed a good results (P<0.5) against S. aureus, K. pneumoniae, P. aeruginosa and E. coli Keywords: Silver nanoparticle, Lagerstroemia speciosa, Anti-bacterial activity. 1. INTRODUCTION Nanoparticles are greatly considered to be a discovery of modern science; they actually have a very long history. Over the decades, silver nanoparticles have been found an application in medicine, catalysis, optics, electronics, water treatment, textile engineering and other areas [1] . In view of biotechnology and bioengineering, its demand has increased to global level. Thus, production of nanomaterials from varying size of 1 to 100 nanometers (nm) is an emerging field of research and which have turned a wide scope in biological systems [2] . * Address for Correspondence Mrs. V. Sai Saraswathi, Asst. Prof. Pharmaceutical Chemistry Division, School of Advanced Sciences, VIT University, Vellore – 632 014. INDIA Email: saisaraswathi@gmail.com Mobile: +91 95668 14287 Among the various inorganic metal nanoparticles, silver nanoparticles have received substantial attention for various reasons –since silver is an effective antimicrobial agent, exhibits low toxicity and has diverse invitro and invivo applications [3-5] . Recently, researchers have made their efforts to incorporate silver nanoparticles into a wide range of medical devices, bone cement, surgical instrument, masks, wound dressings etc. A variety of techniques have been utilized for the enrichment of silver Nanoparticle including extraction using organic solvents or aqueous two phase polymeric systems or the chemical reduction of silver ions in aqueous solution with or without stabilizing agents, thermal decomposition in inorganic solvents and photo reduction. Thus, there is a need for ‘green chemistry’ that includes a nontoxic, clean and environment- friendly method of Nanoparticle synthesis [6] . Similarly, another approach in synthesizing the nanoparticles is achieved using micro-organisms and plants. Further, these biologically synthesized nanoparticles were found to be highly toxic against different bacterial species [7] . India has great potential Research Paper ISSN: 2230 – 7583 V.Sai Saraswathi et al. / International Journal of Advances in Pharmaceutical Research IJAPR Available Online through www.ijapronline.org IJAPR /July 2013/ Vol. 4 /Issue.7 / 1995 – 1999 1995