WHO monographs on selected medicinal plants - travolekar.ru

Cortex Viburni Prunifolii
pore canals and rounded to irregular lumen, which frequently contain reddish
to brownish content. Bast fibres absent. The medullary rays are mostly
1–2 cells wide, and contain either starch, tannin, orange-brownish
amorphous masses or calcium oxalate crystals. Rosette aggregates of calcium
oxalate found in the cells of the cortex, medullary rays and phloem
are up to 54 μm in diameter. Monoclinic crystals also occur in these regions,
but are fewer in number and only up to 25 μm in length. Starch
grains present in these regions are simple and spheroidal to 2–3-compound,
the individual grains being up to 23 μm in diameter (6).
Powdered plant material
Stem bark: light brown to moderate yellowish-brown. Cork layer in surface
view. Stone cells numerous, rounded or elongated, in groups or isolated,
with thick, porous, lignified walls and with reddish to brownish
lumen and up to 260 μm in length; numerous fragments of lignified cork
with brownish walls and polygonal in shape; calcium oxalate in rosette
aggregates and monoclinic prisms up to 57 μm in diameter or length; fragments
composed of parenchyma cells containing starch grains or calcium
oxalate in rosette aggregates or monoclinic prisms, oil globules or orange
to olive brown-coloured amorphous masses; starch grains simple or 2- to
3-compound, the individual grains spheroidal, ovate, elliptical, pyriform
or plano-convex, up to 23 μm in diameter or length; a few fragments having
wood fibres with lignified walls, some with lumen of irregular width
and with bordered pores (3, 6).
Root bark: to be established in accordance with national requirements.
General identity tests
Macroscopic and microscopic examinations (3, 6) and thin-layer chromatography
(1, 3).
Purity tests
Microbiological
Tests for specific microorganisms and microbial contamination limits are
as described in the <strong>WHO</strong> guidelines for assessing quality of herbal medicines
with reference to contaminants and residues (7).
Foreign organic matter
Not more than 3% (1).
Total ash
Not more than 12% (1).
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