Available online at www.scholarsresearchlibrary.com Scholars Research Library J. Nat. Prod. Plant Resour., 2014, 4 (6):1-8 (http://scholarsresearchlibrary.com/archive.html) ISSN : 2231 – 3184 CODEN (USA): JNPPB7 1 Scholars Research Library Biosynthesis of silver nanoparticles by Momordica charantia leaf extract: Characterization and their antimicrobial activities Samuel Alwin David * , Kanagasabai Muruganandam Ponvel, Mohamed Anis Fathima, Solaiappan Anita, Jeyapaul Ashli and Alaguvel Athilakshmi Department of Chemistry, V.O. Chidambaram College, Thoothukudi, Tamil Nadu, India _____________________________________________________________________________________________ ABSTRACT The use of environmentally benign materials such as plant extract for the synthesis of silver nanoparticles (AgNPs) offers numerous benefits of eco-friendliness and compatibility for pharmaceutical and other biomedical applications. In this study, we have used Momordica charantia leaf extract as a reducing agent for the synthesis of AgNPs. Characterization of the AgNPs was done by UV-Visible Spectroscopy, Transmission Electron Microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). An intense surface plasmon resonance band at 418 nm in the UV–visible spectrum clearly revealed the formation of AgNPs. SAED and XRD patterns confirmed the presence of highly crystalline and face-centered cubic structure AgNPs and they were generally found to be spherical in shape with variable size ranging from 10 to 50 nm, as evident by TEM. Phenolic compounds present in Momordica charantia leaf extract were mainly responsible for the reduction and the stabilization of AgNPs. The biosynthesized AgNPs exhibited a strong antibacterial activity against Kelbsilla pneumonia bacteria. Keywords: Green synthesis, silver nanoparticles, Momordica charantia leaf extract, characterization, Antimicrobial Activity. _____________________________________________________________________________________________ INTRODUCTION Synthesis of silver nanoparticles (AgNPs) is a growing area for research due to its potentiality in the application and development of advanced technologies. AgNPs are known to have electrical conducting, magnetic, catalytic, sensing and optical properties [1-3], used in coating or embedding for medical purposes [4] and found to be effective as antibacterial, antiviral, anti- infammatory, anti-angiogenesis, anti-platelet activity etc.[5,6]. In addition to their medical uses, AgNPs are also used in clothing, catalysis, biosensing, bio-labeling, food industry, paints, optics, electronics, imaging, water treatment, selective coatings for solar energy absorption, sunscreens and cosmetics [7- 15]. Momordica charantia is a tropical and subtropical vine of the family Cucurbitaceae, widely grown in Asia, Africa, and the Caribbean for its edible fruit, which is extremely bitter. The Latin name Momordica means "to bite," referring to the jagged edges of the leaves, which appear as if they have been bitten. It has shown antibacterial, anticancerous, antileukemic, antiprotozoal, antitumorous, antiviral, antiparasitic, antifungal , anti-obesity, anti-ulcer, hypoglycemi and, immune stimulant activities [16-20]. It has been used by natural health practitioners for diabetes, cancer, high cholesterol, viral infections and bacterial infections [21, 22]. The main constituents of Momordica charantia responsible for the medicinal properties are triterpenes, proteins, steroids, alkaloids and other phenolic compounds [23, 24].