Next Article in Journal
Spun Biotextiles in Tissue Engineering and Biomolecules Delivery Systems
Next Article in Special Issue
Polyphasic Validation of a Nisin-Biogel to Control Canine Periodontal Disease
Previous Article in Journal
Induction of Melanogenesis by Fosfomycin in B16F10 Cells Through the Upregulation of P-JNK and P-p38 Signaling Pathways
Previous Article in Special Issue
Deep Functional Profiling Facilitates the Evaluation of the Antibacterial Potential of the Antibiotic Amicoumacin
Article

New Labdanes with Antimicrobial and Acaricidal Activity: Terpenes of Callitris and Widdringtonia (Cupressaceae)

1
School of Science and Technology, University of New England, Armidale, NSW 2351, Australia
2
Department of Botany and Plant Biotechnology, University of Johannesburg, Johannesburg 2006, South Africa
3
Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK
4
Department of Entomology, Faculty of Agriculture, Assam Agricultural University, Jorhat, Assam 785013, India
5
Department of Applied Entomology & Zoology, Faculty of Agriculture, Alexandria University, Alexandria 21545, Egypt
*
Author to whom correspondence should be addressed.
Received: 29 March 2020 / Revised: 9 April 2020 / Accepted: 10 April 2020 / Published: 11 April 2020
In spite of the evidence for antimicrobial and acaricidal effects in ethnobotanical reports of Callitris and Widdringtonia, the diterpene acids from Widdringtonia have never been described and no comparison to the Australian clade sister genus Callitris has been made. The critically endangered South African Clanwilliam cedar, Widdringtonia wallichii (syn. W. cedarbergensis), of the Cederberg Mountains was once prized for its enduring fragrant timbers and an essential oil that gives an aroma comparable to better known Mediterranean cedars, predominantly comprised by widdrol, cedrol, and thujopsene. In South Africa, two other ‘cedars’ are known, which are called W. nodiflora and W. schwarzii, but, until now, their chemical similarity to W. wallichii has not been investigated. Much like Widdringtonia, Callitris was once prized for its termite resistant timbers and an ‘earthy’ essential oil, but predominantly guaiol. The current study demonstrates that the essential oils were similar across all three species of Widdringtonia and two known non-volatile diterpene acids were identified in leaves: the pimaradiene sandaracopimaric acid (1) and the labdane Z-communic acid (2) with a lower yield of the E-isomer (3). Additionally, in the leaves of the three species, the structures of five new antimicrobial labdanes were assigned: 12-hydroxy-8R,17-epoxy-isocommunic acid (4), 8S-formyl-isocommunic acid (5), 8R,17-epoxy-isocommunic acid (6), 8R-17R-epoxy-E-communic acid (7), and 8R-17-epoxy-E-communic acid (8). Australian Callitris columellaris (syn. C. glaucophylla) also produced 1 and its isomer isopimaric acid, pisiferal (9), and pisiferic acid (10) from its leaves. Callitris endlicheri (Parl.) F.M.Bailey yielded isoozic acid (11) as the only major diterpene. Diterpenes 46, pisiferic acid (10), spathulenol, and guaiol (12) demonstrated antimicrobial and acaricidal activity. View Full-Text
Keywords: Widdringtonia; Callitris; diterpene; cedar; essential oil; antimicrobial; NMR Widdringtonia; Callitris; diterpene; cedar; essential oil; antimicrobial; NMR
Show Figures

Graphical abstract

MDPI and ACS Style

Sadgrove, N.J.; Senbill, H.; Van Wyk, B.-E.; Greatrex, B.W. New Labdanes with Antimicrobial and Acaricidal Activity: Terpenes of Callitris and Widdringtonia (Cupressaceae). Antibiotics 2020, 9, 173. https://0-doi-org.brum.beds.ac.uk/10.3390/antibiotics9040173

AMA Style

Sadgrove NJ, Senbill H, Van Wyk B-E, Greatrex BW. New Labdanes with Antimicrobial and Acaricidal Activity: Terpenes of Callitris and Widdringtonia (Cupressaceae). Antibiotics. 2020; 9(4):173. https://0-doi-org.brum.beds.ac.uk/10.3390/antibiotics9040173

Chicago/Turabian Style

Sadgrove, Nicholas J., Haytham Senbill, Ben-Erik Van Wyk, and Ben W. Greatrex 2020. "New Labdanes with Antimicrobial and Acaricidal Activity: Terpenes of Callitris and Widdringtonia (Cupressaceae)" Antibiotics 9, no. 4: 173. https://0-doi-org.brum.beds.ac.uk/10.3390/antibiotics9040173

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop