Available online www.jocpr.com Journal of Chemical and Pharmaceutical Research, 2015, 7(2):727-731 Research Article ISSN : 0975-7384 CODEN(USA) : JCPRC5 727 Comparative antibiogram analysis of AgNPs synthesized from two Alternaria Spp. with amoxicillin antibiotics # B. K. Nayak, @ N. Chitra and @ Anima Nanda Department of Botany, K. M. Centre for P.G. Studies (Autonomous), Lawspet, Pondicherry, India @ Department of Biomedical Engineering, Sathyabama University, Rajiv Gandhi Salai, Chennai, India _____________________________________________________________________________________________ ABSTRACT From long time ago, the use of silver nanoparticles to control the growth and prevalence of disease causing bacteria is well known. In recent times, bacteria make themselves resistant to varied antibiotics based on their genes present in the plasmids. During the present study, an effective approach was performed to synthesize potent silver nanoparticles (AgNPs) from two mould fungi; Alternaria sp. and Alternaria alternata. The appearance of yellowish brown color in the conical flask suggested the formation of AgNPs. The extract of the fungus culture changed the solution into brownish color during the reaction. The characterization of silver nanoparticles was confirmed by Uv- Vis spectroscopy, Field emission scanning electron microscopy (FESEM). Size of the nanoparticles measured between 20nm to 30nm by FESEM. The synthesized silver nanoparticles were subjected to their characterization by X-ray diffraction (XRD) technique to determine the metallic nature of nanoparticles. The XRD analysis confirmed that silver nanoparticles have been formed resulting in the diffraction peaks at 38, 45, 64 and 77 respectively showing the metallic nature of nanoparticles and peak were specific for the silver nanoparticles. Silver nanoparticles synthesized from both the fungi showed good antimicrobial activity against the selected bacterial pathogens like, Staphylococcus aureus, Bacillus cereus, Proteus vulgaris, E. coli and Vibrio cholerae and the nanoparticles were found more effective against the test pathogens in combined with the available drugs viz., Amoxicillin (30mcg). The efficacy of the drugs was increased at high level of potency. Key words: AgNPs, Alternaria spp., Antibiogram, Amoxicillin, Uv-Vis Spectrophotometer _____________________________________________________________________________________________ INTRODUCTION Combined form of silver nanoparticles with various antibiotics show antibacterial activity [1]. Silver nanoparticle was used in medicine for its antimicrobial properties from the early of this century and more recently has been used in wound dressings and catheters. It is less reactive in comparison to silver ions, which makes it more suited to medical applications. It has also been shown to induce programmed cell death. Although the antimicrobial properties of silver have been known for long time, but we have recently understand the mechanisms by which silver inhibits the bacterial growth. The current challenge is to measure its activity, to understand the molecular level and then to determine the effective concentrations for therapeutic use. As per current report, bacteria are becoming more resistant to antibiotics, mostly superbugs like methicillin resistant Staphylococcus aureus in hospital communities. Alternate approach for therapies are being researched for antibacterial properties of AgNPs. Nanoparticles have put a great attention in recent days by their promising interdisciplinary fields of science which offers valuable nanomaterials of wide application in the range of areas, including catalysis, optics, mechanics and biomedical sciences [1]. In comparison to physical and chemical process, biological process has an interest because of its cost