Pterocaulon redolens (PROSEA)
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Introduction |
Pterocaulon redolens (Willd.) Fern.-Vill.
- Protologue: Nov. app.: 116 (1880).
- Family: Compositae
- Chromosome number: 2n= unknown
Synonyms
Conyza redolens Willd. (1803), Monenteles spicatus Labill. (1825), Pterocaulon cylindrostachyum C.B. Clarke (1878).
Vernacular names
- Philippines: sambong-gala (Tagalog), subusob (Ilokano)
- Vietnam: bông bống núoc, bọ xít nước.
Origin and geographic distribution
P. redolens occurs in eastern India, Burma (Myanmar), Indo-China, southern China, Thailand, the Philippines, New Guinea, Australia and New Caledonia.
Uses
In the Philippines a decoction of the leaves of P. redolens is used for stimulant baths.
P. sphacelatum (Labill.) Benth. & Hook.f. ex F. v. Mueller from central Java, the Lesser Sunda Islands, New Guinea, Australia and New Caledonia is used in Australian Aboriginal folk medicine for the treatment of colds.
Properties
In a general screening experiment for antiviral activity, the ethanol extract of aboveground parts of P. sphacelatum showed a potent inhibition of poliovirus type 1 at a concentration of 52 μg/ml. Further studies revealed the flavonol chrysosplenol C to be the active compound. This compound is a 4'-hydroxy-3-methoxyflavone, one of a group of compounds known to be potent and specific inhibitors of picorniviral replication. The poliovirus belongs to the picornivirusses, responsible for respiratory and central nervous system infections in humans.
Botany
A perennial, aromatic herb up to 100 cm tall; stems conspicuously winged, variably grey-hairy. Leaves alternate, simple, oblanceolate, (2-)3-5(-7) cm × 0.7-2 cm, base cuneate, apex acute or obtuse, denticulate to almost entire, densely woolly above, thinly so below; petiole with decurrent wings; stipules absent. Inflorescence composed of small heads c. 4 mm long, forming terminal spike-like clusters 2-5 cm × 0.8-1 cm; outer involucral bracts oblong, shortly apiculate, densely woolly, inner ones much longer, glabrous, falling off together with the flowers. Flowers all tubular; marginal flowers female, numerous, 2-3 mm long, with slender corolla, entire or very shallowly toothed; disk flower bisexual, solitary, corolla cylindrical, 5-lobed, lobes papilose outside; stamens 5, anthers fused; ovary inferior, 1-celled, style with 2 filiform arms, exserted in female flowers. Fruit an oblong achene c. 1 mm long, obscurely angular, glabrous to pubescent; pappus hairs thin, c. 2 mm long, dentate.
Pterocaulon comprises 18 species and has a disjunct distribution, 12 species occurring in the Americas and 6 in South-East Asia, Australia and New Caledonia.
Ecology
P. redolens occurs in open localities, e.g. wasteland, at low to medium altitudes.
Genetic resources
P. redolens is relatively widespread and commonly encountered in disturbed habitats, and thus is not threatened by genetic erosion.
Prospects
There is no information on the pharmacological properties of P. redolens . The observed antiviral activity of P. sphacelatum against poliovirus 1 supports further research on this species and P. redolens , and these species may be a possible template in the development of future phytomedicines.
Literature
124, 760, 834, 835.
Other selected sources
112, 264.
Main genus page
Authors
A.M. Aguinaldo
