GREEN SYNTHESIS AND CHARACTERIZATIONS OF SILVER NANOPARTICLES USING FRESH LEAF EXTRACT OF MORINDA CITRIFOLIA AND ITS ANTI-MICROBIAL ACTIVITY STUDIES Short Communication ASHA R PAI a* , KAVITHA S a , SHWETA RAJ S. a , PRIYANKA P a , VRINDA A a , VIVIN T. S. a , SILPA SASIDHARAN a a Received: 22 Oct 2014 Revised and Accepted: 15 Nov 2014 Amrita School of Biotechnology, Amrita Vishwa Vidyapeetham, Amritapuri, Kollam 690525 Email: asharp@am.amrita.edu ABSTRACT Objective: To develop a rapid method of synthesis of silver nanoparticles (Ag NPs) using the fresh aqueous leaf extract of Morinda Citrifolia from 0.1 M AgNO3 Methods: 25 ml of the aqueous extract was added to 25 ml of 0.1 M aqueous AgNO solution, to characterize the resulting Ag NPs and also compare their antimicrobial activity with those of standard drugs against human pathogenic bacteria. 3 Results: The formation of Silver nanoparticles was confirmed with the help of UV-Vis absorption spectra at ≈ 425 nm and particle size as approximately 100 nm using Particle size analysis (DLS method). The anti-microbial activity of the Ag NPs so synthesized was studied against human pathogens in wound infections such as S. aureus and P. aureginosa strains. The inhibitory activity for Ag NPs was compared with those of known drugs such as tetracycline, Ceftazidime and Amikacin at 30 mcg. The inhibitory activity of the Synthesized Ag NPs was found pronounced against P. aureginosa strains. at room temperature. The mixture was stirred continuously for 5-10 minutes. The reduction was completed with the appearance of brownish-black colored dispersion. The resulting nanoparticles were characterized using UV-Vis absorption spectra and Particle size analysis (DLS method). Further the Antimicrobial activity was compared with the drugs against S. aureus and P. aureginosa strains using the disk diffusion method. Conclusion: A rapid method of synthesizing Ag NPs has been developed by using the fresh leaf extract of Morinda Citrifolia and it was found that the extract is a potential reducing agent to produce stable Ag NPs. The research provides a new input to the development of anti-microbial agent. Keywords: Nanomaterial, Green synthesis, Silver nanoparticles, Morinda Citrifolia, Anti microbial activity. Nanomaterials are synthesized from the novel, eco-friendly and sustainable techniques of physical, chemical, biological and engineering processes. In this 21 st In biological method, the plant extracts has been used as reducing agent and capping agent for the synthesis of nanoparticles [3] due to their reducing properties [4]. Some properties such as size, distribution, and morphology of the particles are clearly obtained from the nanoparticles [5]. Silver nanoparticle acts as antimicrobial agent which finds applications in medical field such as Ag NPs coated blood collecting vessels, coated capsules, band aids etc., [3 - 6]. The silver is non toxic to animal cells and highly toxic to bacteria and other microorganisms such E coli, P. aeroginosa, S. aureus etc. Due to these phenomena it is considered to be a safe and effective bactericidal metal [7 - 9] and therefore can be incorporated with several materials such as cloths, ointments etc. The band aids so developed are highly sterile and therefore can be useful in the hospitals to prevent or to minimize the infections with pathogenic bacteria such as E coli, S. aureus etc,.[10]. century, the nanotechnology has emerged as an interdisciplinary field with the biosynthesis of metal nanoparticles. Nanotechnology is gaining importance in various fields such as health care, food and feed, cosmetics, environmental health, biomedical science, chemical industries, drug and gene delivery, energy science, electronics, mechanics and space industries. There are many ways to synthesis nanoparticles such as solid reaction, co-precipitation, chemical reaction and sol gel method etc, [1]. Bio-based approaches for the synthesis of nanoparticles are rapidly gaining importance due to their ease of synthesis, eco- friendliness and formation of stable and biocompatible nanoparticles. Bacteria, fungi, plants and seaweeds are the potential sources utilized for the synthesis of nanoparticles [2]. The green synthesis with plant extracts are simpler and advantageous over other biological processes as they are safe to handle. Synthesis of silver nanoparticles using plant extracts have been reported in Boswellia ovalifolilata, Shorea tumbuggaia Svensoina hyderobadensis, Thespesia populnea, Vinca rosea [11], Cassia auriculata [12]. Morinda citrifolia (Noni) has been extensively used in folk medicine for over 2,000 years. It has been reported to have broad therapeutic effects, including cancer activity, in both clinical practice and laboratory animal models [13]. Noni has traditionally been used for colds, flu, diabetes, anxiety, and high blood pressure, as well as for depression and anxiety. The green fruit, leaves, and root/rhizomes were traditionally used in Polynesian cultures to treat menstrual cramps, bowel irregularities, diabetes, liver diseases, and urinary tract infections [14]. The mechanism for these effects remains unknown [15 - 19]. Hence, in the present work, a very rapid green synthesis of silver nanoparticles using the leaf extract of Morinda citrifolia is investigated and their anti microbial activities are studied against human pathogenic bacteria such as S. aureus and P. aeroginosa are compared with the standard drugs in the market. 5 grams of fresh leaves of the plants were collected and washed with distilled water 3-4 times to remove the dust particles. Leaves were chopped into small pieces and mixed into 150 ml distilled water separately. Mixture was stirred at 800 rpm for 3 hrs in magnetic stirrer. The aqueous extract was separated by filtration with whatmann No. 1 filter paper. The filtrate was collected and stored at 4 o The extract stored was used for biosynthesis of silver nanoparticles from silver nitrate. 25 ml of the prepared extract was added to 25 ml of aqueous AgNO C. 3 Ag NO (0.1M in 100 ml) at room temperature. The mixture was stirred continuously for 5-10 minutes. 3 → Ag + +NO 3 Ag + + 2H 2 O→Ag 0 +4H + +O 2 − The reduction was completed with the appearance of brownish- black color which confirms the formation of silver nanoparticles. The contents were centrifuged at 8, 000 rpm for 10 minutes. The supernatant was used for the characterization of Silver nanoparticles. The bioreduction of Silver ions was studied the UV- VIS spectrophotometer. International Journal of Pharmacy and Pharmaceutical Sciences ISSN- 0975-1491 Vol 7, Issue 3, 2015 Innovare Academic Sciences