Pak. J. Pharm. Sci., Vol.28 No.6, November 2015, pp.1947-1951 1947 Coumarins and flavonoid from Murraya paniculata (L.) Jack: Antibacterial and anti-inflammation activity Pirasut Rodanant 1 *, Pichit Khetkam 2 , Apichart Suksamrarn 2 and Jintakorn Kuvatanasuchati 3 1 Department of Advanced General Dentistry, Faculty of Dentistry, Mahidol University, Bangkok, Thailand 2 Department of Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand 3 Department of Microbiology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand Abstract: The ethyl acetate extract of leaves of Murraya paniculata (L.) Jack was described in the previous in vitro study on the inhibition effect on the growth of periodontopathic bacteria and the reduction of cytokines from LPS- stimulated macrophages. In this study, four coumarins including murrangatin (1), murrangatin acetate (2), murranganonesenecionate (3), micropubescin (4) and one flavonoid, 3',4',5',7-tetramethoxyflavone (5) were isolated from the leaves of ethyl acetate extract of M. paniculata. MTT assay was used to test cytotoxicity on human gingival fibroblast and monocytes. The isolated compounds were evaluated for their antibacterial effect against Porphyromonas gingivalis (ATCC33277) and anti-inflammation on lipopolysaccharide-stimulated inflammation using monocyte cells. All isolated compounds exhibited antibacterial activity against P. gingivalis (ATCC 33277). Murranganonesenecionate (3) was highly potent anti-inflammation properties. The coumarin constituents from M. paniculata leaves might be potential lead molecules for the development of antimicrobial drugs for treating periodontal disease. Keywords: Murraya panicuata (L.) Jack, coumarins, flavonoid, antibacterial, anti-inflammation. INTRODUCTION Murraya paniculata (L.) Jack (Rutaceae), which is known in Thai as Kaew, is an 8-12 feet high medium-sized shrub. Its flowers are white and fragrance, which bloom all the year round. Its leaves are green and ovate in shape, with less than 2 inches of blade length, alternately arranged on the branch. Its leaves and roots have traditionally found wide medicinal uses in southeast Asia and China (Imai et al., 1989). Chemical constituents from this plant including flavonoids (Kinoshita and Firman, 1996), flavones (Yang and Du, 1984), indole alkaloids (Kong et al., 1985), coumarins (Kinoshita et al, 1996), monoterpenes (Li et al., 1988), sesquiterpenes (Chowdhury et al., 2008) and cinnamates (Rahman et al., 1997). Coumarins and cinnamates exhibited antioxidant, antimicrobial and anticancer activity (Rahman et al., 1997; Ng et al., 2012). To our knowledge, its ethyl acetate fraction of crude extract from its leaves exerted inhibitory effect on the growth of periodontopathic bacteria (Rodanant et al., 2010) and could reduce the release of cytokines, IL-1β and TNF-α, from LPS-stimulated macrophages (Rodanant et al., 2012). Previous chemical investigations of plant from Rutaceae family demonstrated the isolation of various phytochemical constituents including coumarins and flavonoids (Jiwajinda et al., 2000; Kinoshita and Firman, 1997). Natural coumarins and flavonoids from plants have been shown to exert antimicrobial and anti- inflammation activities (Creaven et al., 2006; Xu and Lee, 2001; Serafini et al., 2010; Hadjipavlou-Litina et al., 2007). The potency of these secondary metabolites might benefit the treatment of periodontal disease, a chronic inflammation initiated by bacterial contamination, which continues to breakdown periodontium through the activation of host defence cells (Page, 1991). Although there are extensive uses of antimicrobial and anti- inflammatory drugs, prolonged consumption might exert numerous side effects or developing drug resistance. The need for alternative strategies to lower the incidence of those unwanted phenomenon is warranted. The purpose of this in vitro study was to continue our research on evaluation of biologically active compounds of M. paniculata leaves for its potential antibacterial and anti- inflammation activities. These could be helpful in providing a rationale for the ethnomedicinal use of the plant. Cytotoxicity of the isolated compounds to human gingival fibroblasts (HGFs) and monocytes (U937) were also investigated. MATERIALS AND METHODS Plant materials M. paniculata leaves were collected in Hua Mark District, Bangkok. Voucher specimen was identified by Associate Professor Nopporn Dumrongsiri and archived in the herbarium of the Faculty of Science, Ramkhamhaeng University. Extraction and isolation The air-dried plant leaves (1.64kg) were pulverized and extracted thoroughly with n-hexane, ethyl acetate (EtOAc) and methanol (MeOH). The EtOAc extract (103.76g) was subjected to repeat silica column chromatography using dichloromethane/MeOH as eluent *Corresponding author: e-mail: pirasut.rod@mahidol.ac.th