1 Document heading In-vitro antibacterial activity on human pathogens and total phenolic, flavonoid contents of Murraya paniculata Linn. leaves Manish K Gautam 1 , Mayank Gangwar 1,2 , Gopal Nath 2 , Chandana V Rao 3 , Raj K Goel 1* 1 Department of Pharmacology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India 2 Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India 3 Pharmacognosy and Ethnopharmacology Division, National Botanical Research Institute (CSIR), Lucknow 226001, India Asian Pacific Journal of Tropical Biomedicine (2012)1-4 Asian Pacific Journal of Tropical Biomedicine journal homepage:www.elsevier.com/locate/apjtb *Corresponding author: Prof. Raj Kumar Goel, Department of Pharmacology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India Tel: +91-0542-2307522 Fax: +91-0542-2367568 E-mail: manishpharmacology@gmail.com 1. Introduction Bacteria are extremely pathogenic causing serious human infection and widespread use of commercially available antibiotics led to developed resistance or ability to produce substances which block the action of antibiotics or change their target and produce undesirable side effects. Tuberculosis, malaria and gonorrhea infection are just a few disease that have become harder to treat with antibiotics [1] . Plants remain the most common source of antimicrobial agents. Their usage as traditional health remedies is the most popular for 80% of world population in Asia, Latin America and Africa and is reported to have minimal side effects. The screening of plant extracts for antimicrobial activity has shown that plants signify a potential source of new antibacterial agent [2] . Phenolic compounds are one of the main secondary metabolites, present in the plants and these are an integral part of the human diet. Phenolic compounds are commonly known for their antioxidant, anti- inflammatory and antimicrobial activities [3] . Flavonoids, the most common group of polyphenolic compounds that are found ubiquitously in plants kingdom. More than 5 000 flavonoids have been identified in nature. Flavonoids are most commonly known for their antioxidant activity and reduce lipid peroxidation not only by preventing or slowing the onset of cell necrosis but also by improving vascularity [2] . Murraya paniculata (M. paniculata) Linn., commonly known as orange jasmine or honey bush (Kamini in Hindi) belongs to the family Rutaceae. It is distributed throughout India, Bangladesh, tropical Srilanka to Myanmar, southern China and Taiwan, Thailand and eastwords throughout the Malesian region to northeastern Australia and Caledonia. The leaves are stimulant and astringent; they are reportedly used in the form of an infusion to treat diarrhoea and dysentery in the Philipines. The powder leaves are applies to cuts to promote healing; there decoction is taken ARTICLE INFO ABSTRACT Article history: Received 15 April 2011 Received in revised form 27 April 2011 Accepted 28 June 2011 Available online 28 June 2011 Keywords: Murraya paniculata Linn Antibacterial MIC MBC Folin-Ciocalteu Quercetin Objective: To deals with in-vitro antibacterial analysis of Murraya paniculata Linn. (Rutaceae) leaves extract on human pathogens in different solvent and determination of total phenolic and flavonoid contents in petroleum ether, methanol, ethanol and hydro-alcoholic extract of the plant. Methods: These extracts were tested against various human pathogens for antimicrobial activity which was evaluated by disc diffusion method and minimum inhibitory concentration (MIC) and minimum bactericidal concentration was calculated by micro dilution method. Phenolic content was estimated by using folin ciocalteau reagent and flavonoids by using aluminium chloride reagent against quercetin equivalent. Results: The methanolic extract of leaf showed marked antibacterial activities against gram-positive and gram-negative bacteria. Methanolic extract of Murraya paniculata leaf contain higher phenolic content (24.80依0.64) followed by ethanolic fraction (15.40依0.38), pet. Ether (13.50依0.96) and hydro-alcoholic (9.06依1.13). Flavonoid content was found to be maximum in pet. ether extracts (3.38依1.89). Conclusions: Murraya paniculata leaves posses antibacterial properties against human pathogens with high content of phenolic and flavonoids, which have supportive action of antibacterial activity. Studying plant based antimicrobial properties provides additional information in developing nature antibiotics and discovering the alternative of antimicrobial drugs for the treatment of infectious disease. Contents lists available at ScienceDirect