Abstract
While it has been known for some time that certain species of plants contain photosensitizers, it is only recently that the raison d’être of light activated toxins has been demonstrated. All of these photosensitizers fall into a diverse group of secondary compounds with no known function in primary metabolism such as photosynthesis, nitrogen assimilation etc., but have been shown to act as defenses against phytophagous insects and fungal pests. Evolution of the biosynthetic pathways leading to these compounds has probably occurred through a co-evolutionary process where pressure by herbivores or other pests has led to the selection of chance mutations which have produced novel, increasingly complex and toxic secondary substances. For example, work by Berenbaum (1983) has shown that while the widely distributed phytochemical umbelliferone is relatively non-toxic to armyworms, its derivative, xanthotoxin of the Apiaceae, formed biosynthetically by prenylation and cycli-zation, is phototoxic to this insect when ingested. Expression of toxicity was clearly shown to be dependent on irradiation by photosensitizing wavelengths. Other studies have shown that ingested plant photooxidants such as alpha terthienyl or phenylheptatriyne (Champagne et al.,1986; Downum et al., 1984) can cause black necrotic lesions and pupal deformities to develop in phytophagous larvae at acute doses, or at lower doses lengthen their development time and reduce final weights.
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Alkofahi, Α., J.K. Rupprecht, J.E. Anderson, J.L. McLaughlin, K.L. Mikolajczak and B.A. Scott (1989) Search for new pesticides from higher plants. Amer. Chem. Soc. Symp. Ser. 387, 25–43.
Arnason, J.T., P. Morand, J. Salvador, I.Reyes and G.H.N.Towers (1983) Phototoxic substances from Flaveria trinervis and Simira Salvadorensis. Phytochem. 22, 594.
Arnason, J.T., Β. J.R. Philogène, P. Morand, K. Imrie, Β Hasspieler and A.E.R. Downe (1989) Naturally occurring and synthetic thiophenes as insecticides. Amer. Chem. Soc. Symp. Ser. 387, 164–172.
Aucoin, R., J.T. Arnason (1990) The protective effect of antioxidants to a phototoxin sensitive insect herbivore J.Chem.Ecol., 16, 2913–2924.
Berenbaum, M. (1983) Coumarins and caterpillars: a case for co-evolution. Evolution 37, 163–179.
Bohlmann, F.,T. Burkhardt, and C. Zdero (1973) Naturally Occurring Acetylenes. Academic Press.
Camm E.L., G.H.N. Towers and J.C. Mitchell (1975) UV mediated antibiotic activity of some Compositae species. Phytochem. 14, 2007–2011.
Champagne, D.E., J.T. Arnason, B.J.R. Philogène, P. Morand and J. Lam. (1986) Light mediated allelochemi-cal effects of naturally occurring polyacetylenes and thiophenes from theAsteraceae on herbivorous insects. J. Chem. Ecol. 12, 835–858.
Downum, K.R., G.A. Rosenthal and G.H.N. Towers (1984) Phototoxicity of the allelochemical, alpha-terthienyl to larvae of Manduca sexta Pest. Biochem. Physiol. 22, 14–109.
Fields, P., J.T. Arnason and B.J.R. Philogène (1989) The behavioral and physical adaptation of 3 insects that feed on the phototoxic plant Hypericum perforatum. Can. J. Zool. 68, 339–346.
Fields, P.G., J.T. Arnason and R.G. Fulcher (1990) The spectral properties of Hypericum perforatum leaves: The implications for its photoactivated defenses. Can. J. Bot. 68, 1166–1170.
Gommers, F. and J. Bakker (1988) Mode of action of alpha-terthienyl and related compounds may explain the supression effects of Tagetes species on populations of free living endoparasitic nematodes. Bioactive Molecules 7, 61–70.
Hudson, J.B. (1989) Antiviral properties of photosensitizers used in dermatology: Recent advances and alternative interpretations. Photodermatol. 6, 155–165.
Kourany, E., J.T. Arnason and E. Schneider (1988) Accumulation of phototoxic thiophenes in Tagetes erecta elicited by infection with Fusarium oxysporum. Physiol. Molec. Plant Pathol. 33, 287–298.
Knox, J.P. and A.D. Dodge (1985) Singlet oxygen and plants. Phytochem. 24, 889–896.
Sandberg, S. and Berenbaum, M. (1989) Leaf-tying by tortricid larvae as an adaptation for feeding on phototoxic Hypericum perforatum. J. Chem. Ecol. 15, 875–885.
Towers, G.H.N. (1984) Interaction of light with phytochemicals. Can. J. Bot. 62, 29.
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© 1991 Springer Science+Business Media New York
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Arnason, J.T., Marles, R.J., Aucoin, R.R. (1991). Isolation and Biological Activity of Plant Derived Phototoxins. In: Valenzeno, D.P., Pottier, R.H., Mathis, P., Douglas, R.H. (eds) Photobiological Techniques. NATO ASI Series, vol 216. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-3840-0_13
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DOI: https://doi.org/10.1007/978-1-4615-3840-0_13
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