Antibacterials and modulators of bacterial resistance from the immature cones of Chamaecyparis lawsoniana

Smith, Eileen C. J., Williamson, Elizabeth M., Wareham, Neale, Kaatz, Glenn W. and Gibbons, Simon (2007) Antibacterials and modulators of bacterial resistance from the immature cones of Chamaecyparis lawsoniana. Phytochemistry, 68 (2). pp. 210-217. ISSN 0031-9422

Full text not available from this repository. (Request a copy)

Abstract

As part of an on-going project to characterize compounds from immature conifer cones with antibacterial or modulatory activity against multidrug-resistant (MDR) strains of Staphylococcus aureus, eight compounds were isolated from the cones of Chamaecyparis lawsoniana. The active compounds were mainly diterpenes, with minimum inhibitory concentrations ranging from 4 to 128 μg/ml against MDR effluxing S. aureus strains and two epidemic methicillin-resistant (EMRSA) clinical isolates. The compounds extracted were the diterpenes ferruginol, pisiferol and its epimer 5-epipisiferol, formosanoxide, trans-communic acid and torulosal, the sesquiterpene oplopanonyl acetate and the germacrane 4β-hydroxygermacra-1(10)-5-diene. Some of these compounds also exhibited modulatory activity in potentiating antibiotic activity against effluxing strains and ferruginol, used at a sub-inhibitory concentration, resulted in an 80-fold potentiation of oxacillin activity against strain EMRSA-15. An efflux inhibition assay using an S. aureus strain possessing the MDR NorA efflux pump resulted in 40% inhibition of ethidium bromide efflux at 10 μM ferruginol (2.86 μg/ml). We report the 1H and 13C NMR data for the cis A/B ring junction epimer of pisiferol which we have named 5-epipisiferol. We also unambiguously assign all 1H and 13C NMR resonances for trans-communic acid.

Item Type: Article
Faculty \ School: Faculty of Science > School of Pharmacy
Related URLs:
Depositing User: LivePure Connector
Date Deposited: 27 Jun 2020 00:02
Last Modified: 27 Jun 2020 00:02
URI: https://ueaeprints.uea.ac.uk/id/eprint/75793
DOI: 10.1016/j.phytochem.2006.10.001

Actions (login required)

View Item View Item