Shrubs or trees with mostly pinnate leaves; the stems and often the leafstalks are prickly. X. americanum is an indigenous
shrub, 10 or 12 ft in height, with alternate branches, which are armed with strong, conical, brown prickles and broad base,
scattered irregularly, though most frequently in pairs at the insertion of the young branches. The leaves are alternate and pinnate; the
leaflets about five pairs, with an odd one, nearly sessile, ovate, acute, with slight vesicular serratures and somewhat downy underneath;
the common petiole is round, usually prickly on the back. The flowers are borne in small, dense, sessile umbels near the origin
of the young branches; they are small, greenish, dioecious or polygamous, and appear before the leaves. The aromatic, pungent bark is
used in the southern United States as a rustic remedy for toothaches. The parts used are bark and berries. Prickly ash has a bittertonic,
aromatic taste; when taken into the mouth, it actually causes the tongue to twinge.
天然物の起源
Reported found in beer and coffee.
Composition
Both species of Xanthoxylum contain small amounts of volatile oil, fat, sugar, gum, acrid resin, a bitter alkaloid
(believed to be berberine) and a colorless, tasteless, inert, crystalline body, Xanthoxylin, which is slightly different in the two barks.
Both species yield a large amount of ash: 12% or more. The name xanthoxylin is also applied to a resinous extractive prepared by
pouring a tincture of the drug into water. The fruits are also reported to have similar constituents to that of the bark.
