Biochemical Systematics and Ecology 28 (2000) 183}184
An insecticidal quassinoid from the new Australian species Quassia sp. a!. bidwillii Zahid Latif!, Lyn Craven", T.G. Hartley", Brian R. Kemp#, Janet Potter#, Martin J. Rice#, Roger D. Waigh!, Peter G. Waterman!,* !Phytochemistry Research Laboratories, Department of Pharmaceutical Sciences, University of Strathclyde, Glasgow G1 1XW, UK "Australian National Herbarium, Canberra, ACT 2601, Australia #Zeneca Agrochemicals, Jealott's Hill Research Station, Bracknell, Berkshire RG12 42EY, UK Received 17 December 1998; accepted 1 March 1999
Keywords: Quassia sp. a!. bidwillii; Simaroubaceae; Quassinoid; Insecticidal activity; Chemotaxonomy; Chapparinone
1. Subject and source Quassia sp. a!. bidwillii is a newly discovered taxon known only from north-eastern New South Wales, Australia (Hartley, personal communication). Aerial parts were collected on the upper slopes of Mount Nardi, in rainforest, about 10.25 km from Nimbin and studied for phytochemical content and insecticidal activity. A voucher specimen (Craven and Walken 9339) has been deposited at the Australian National Herbarium, Canberra.
2. Previous work No previous work has been reported on this species.
* Corresponding author. Current address. Centre for Phytochemistry and Phytopharmacology, Southern Cross University, PO Box 157, Lismore, NSW 2480, Australia. Tel.:#61-2-6620-3544; fax.:#61-26622-3180. E-mail address:
[email protected] (P.G. Waterman) 0305-1978/00/$ - see front matter ( 2000 Elsevier Science Ltd. All rights reserved. PII: S 0 3 0 5 - 1 9 7 8 ( 9 9 ) 0 0 0 4 2 - 3
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Z. Latif et al. / Biochemical Systematics and Ecology 28 (2000) 183}184
3. Present study The methanol extract of the dried, ground aerial parts of Q. sp. a!. bidwillii (500 g) was tested for insecticidal activity as described previously (Latif et al., 1998). Lethal activity was found against the two-spotted spider mite (Tetranychus urticae), peach/potato aphid (Myzus persicae) and the root knot nematode (Meloidogyne incognita) at 10,000 ppm. The extract was subjected to gel "ltration chromatography (Sephadex LH-20 eluting with water with increasing amounts of MeOH) with the earliest fractions showing activity. Subsequent fractionation was carried out using CC on C reverse phase silica eluting again with H O/MeOH. Finally the active fraction 18 2 was puri"ed using C reverse phase HPLC eluting with 40% MeOH in H O to give 18 2 5 mg of an active pure compound. This was identi"ed as the quassinoid chapparinone using 1D and 2D 1H and 13C NMR and a comparison with literature values where available (Polonsky and Bourguignon-Zylber, 1965; Polonsky et al., 1975; Hamburger and Cordell, 1987; Latif, 1997). In further tests chapparinone showed the following activity (LC "Lethal Concentration for 50% death): spider mite LC "47.0 ppm, 50 50 peach/potato aphid LC "14.9 ppm. 50 4. Chemotaxonomic and ecological signi5cance Quassinoids are, as a class of compounds, found exclusively in the Simaroubaceae (Polonsky, 1983) and so the occurrence of chapparinone was unsurprising. Chapparinone has previously been reported to show activity against the tobacco budworm (Heliothis virescens LC "30 ppm) and feeding inhibition against the fall armyworm 50 (Spodoptera frugiperda) (Klocke et al., 1985) and the Mexican bean beetle (Epilachna varivestis) (Leskinen et al., 1984). Acknowledgements Z. Latif wishes to thank the BBSRC and Zeneca Agrochemicals for the award of a scholarship. NMR studies were performed at the University of Strathclyde NMR laboratory. References Hamburger, M.O., Cordell, G.A., 1987. Planta Med 54, 352. Klocke, J.A., Arisawa, M., Handa, S.S., Kinghorn, A.D., Cordell, G.A., Farnsworth, N.R., 1985. Experientia 41, 379. Latif, Z., 1997. Ph.D. Thesis, University of Strathclyde, Glasgow. Latif, Z., Hartley, T.G., Rice, M.J., Waigh, R.D., Waterman, P.G., 1998. J. Nat. Prod. 61, 614. Leskinen, V., Polonsky, J., Bhatnagar, S., 1984. J. Chem. Ecol. 10, 1497. Polonsky, J., 1983. In: Waterman, P.G., Grundon, M.F. (Eds.), Chemistry and Chemical Taxonomy of the Rutales. Academic Press, London, p. 247. Polonsky, J., Baskevitch, Z., Gottlieb, H.E., Hagaman, E.W., Wenkert, E., 1975. J. Org. Chem. 40, 2499. Polonsky, J., Bourguignon-Zylber, N., 1965. Bull. Soc. Chim. Fr. 2793.
