Antioxidant and antibacterial activities of the leaf essential oils of Himalayan Lauraceae species Subhash C. Joshi a , Arti R. Verma b , Chandra S. Mathela a, * a Department of Chemistry, Kumaun University, Nainital 263002, India b Pharmacognosy and Ethnopharmacology Division, National Botanical Research Institute, Lucknow 226001, India article info Article history: Received 23 July 2009 Accepted 11 September 2009 Keywords: Antioxidant Antibacterial Lauraceae Essential oils MIC abstract The leaf essential oils from seven Himalayan Lauraceae species viz. Neolitsea pallens, Lindera pulcherrima, Dodecadenia grandiflora, Persea duthiei, Persea odoratissima, Persea gamblei and Phoebe lanceolata exhibited potent antioxidant and antibacterial activities. The in vitro antioxidant activity was assessed by using b- carotene bleaching assay, reducing power, DPPH radical scavenging and inhibition of lipid peroxidation methods. The oils of D. grandiflora and L. pulcherrima showed a potent free radical scavenging activity as evidenced by low IC 50 value for DPPH radical (0.032 mg/ml and 0.087 mg/ml, respectively) and inhibition of lipid peroxidation (in between IC 50 = 0.44 mg/ml and IC 50 = 0.74 mg/ml, respectively). The oils were tested against three Gram negative (Escherichia coli, Salmonella enterica enterica and Pasturella multocida) and one Gram positive (Staphylococcus aureus) bacteria at different concentrations using disc diffusion and tube dilution methods. The inhibition zones (IZ) and MIC values for bacterial strains were in the range of 8.7–22.0 mm and 3.90–31.25 ll/ml, respectively. Ó 2009 Elsevier Ltd. All rights reserved. 1. Introduction The Lauraceae species, generally known for spicy leaves, are comprised of about 55 genera and over 2000 species, mostly in warm, tropical, humid subtropical and mild temperate regions of northern and southern hemispheres (Kostermans, 1957). In Hima- layan region, 15 species belonging to six genera viz. Neolitsea, Lin- dera, Persea, Dodecadenia, Phoebe and Cinnamomum have been reported (Gupta, 1968; Polunin and Stainton, 1984; Naithani, 1985). The leaves and bark of some of these species are ingredients of spices and flavoring agents. The leaves mixed with other ingre- dients are also used in the preparation of the tonic. The Cinnamo- mum tamala leaves are commonly used as spices in Indian dishes and reported to possess antioxygenic, antibacterial and fungicidal activities (Gaur, 1999; Semwal et al., 1999). Chemosystematics of some Lauraceae species have been reported earlier (Gottlieb, 1972; Hayashi and Komae, 1980). The terpenoid compositions of the leaf essential oils of Himalayan Lauraceae revealed the dominant presence of furanosesquiterpenoids viz. furanogermenone, furanodienone, curzerenone and furanodiene besides mono and sesquiterpene hydrocarbons (Padalia et al., 2007; Joshi et al., 2007, 2009). Furanogermenone, a constituent of the essential oil of Neolitsea pallens has been established as an allergy inhibitor and antiulcer agent (Watanabe et al., 1986). Furanodienone and curzerenone, the major constituents of Lindera pulcherrima are known to possess insecticidal, anti-inflammatory, antimicrobial and analgesic activities (Dakebo et al., 2002). Previous studies on the leaf essential oils of Lauraceae species revealed antioxidant, antibacterial, fungicidal, cytotoxic, and cruzain inhibitory activities (Girgune et al., 1978; Baratta et al., 1998; Semwal et al., 1999; Schmidt et al., 2006; Moriarity et al., 2007; Setzer et al., 2007; Wright et al., 2007). Present com- munication deals with antioxidant and antibacterial activities of essential oils of seven Himalayan Lauraceae species from Uttarak- hand, India. To the best of our knowledge there is no previous re- port on the antioxidant and antibacterial activities of the leaf essential oils of N. pallens, L. pulcherrima, Dodecadenia grandiflora, Persea duthiei, Persea odoratissima, Persea gamblei and Phoebe lanceolata. 0278-6915/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.fct.2009.09.011 Abbreviations: AOA, antioxidant activity; ASE, ascorbic acid equivalent; CFU, colony forming units; DMSO, dimethyl sulphoxide; DPPH, 1,1 0 -diphenyl-2-pic- rylhydrazyl; FRSA, free radical scavenging activity; GC, gas chromatography; GC– MS, gas chromatography–mass spectrometry; HPLC, high performance liquid chromatography; I, percentage inhibition of DPPH; IC 50 , half maximal inhibitory concentration; IZ, zone of inhibition; LPO, lipid peroxidation; MIC, minimum inhibitory concentration; MTCC, microbial type culture collection; RP, reducing power; TBA, thiobarbituric acid; TBARS, thiobarbituric acid-reactive substances; TCA, trichloroacetic acid. * Corresponding author. Tel.: +91 05942 236943. E-mail address: mathelacs@gmail.com (C.S. Mathela). Food and Chemical Toxicology 48 (2010) 37–40 Contents lists available at ScienceDirect Food and Chemical Toxicology journal homepage: www.elsevier.com/locate/foodchemtox