Geographic variation in alkaloid content of Sanguinaria canadensis (Papaveraceae)
1990; New England Botanical Club; Volume: 92; Issue: 870 Linguagem: Inglês
ISSN
1938-3401
AutoresBradley C. Bennett, Chip R Bell, R. T. Boulware,
Tópico(s)Phytochemistry and biological activities of Ficus species
ResumoWe sampled Sanguinaria canadensis L. (bloodroot) rhizomes from 100 eastern U.S. populations to assess variation in the alkaloid sanguinarine. Sanguinarine content varied from 0.6% to 6.3% of rhizome dry weight (mean 2.7%). This variation correlates with latitude, longitude, slope, clay content, litter depth, rhi zome size, and fruit size. A regression with latitude, pH, and percent humic matter accounted for 58% of the alkaloid variation among populations. Alkaloid con centrations also vary seasonally. Highest alkaloid levels occurred during flowering and fruiting stages. Alkaloids occur in more than 300 plant families (Li and Wil laman, 1972) and are particularly abundant in Fabaceae, Papav eraceae, Ranunculaceae, and Solanaceae. The function of these secondary metabolites is uncertain. They may be metabolic wastes, nitrogen storage compounds, plant pigments, biochemical regu lators, plant growth substances, or defense compounds (Robinson, 1974, 1979; Seigler, 1977; Waller and Nowacki, 1978; Rhoades, 1979). Despite their uncertain biological role, alkaloid synthesis requires substantial metabolic investments. Nicotine production in tobacco may require 10% of the plant's metabolic output (Rob inson, 1974). Sanguinaria canadensis L., a monotypic, alkaloid-bearing member of Papaveraceae, grows throughout the eastern and mid western U.S. (Ernst, 1962). One of the earliest spring-flowering species, Sanguinaria is most abundant on cool, moist, well drained, wooded slopes. Rhizomes produce one or two leaves, each borne on an elongate petiole. Both the generic name, San guinaria, and the common name, bloodroot, describe the deep orange-red latex found in the rhizome. The color is due to the water-soluble, benzophenanthridine alkaloid sanguinarine.
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