NIS - libdoc.who.int - World Health Organization

Folium Plantaginis majoris
epidermis (polygonal cells with slightly sinuous cell walls). There are anomocytic
stomata on both epidermises, but mainly on the lower one. The
epidermal cells occasionally have a striated cuticle. There are rosettes of
epidermal cells with attached or detached trichomes of two types: simple
and glandular. The simple trichomes are multicellular, smooth, with an
enlarged base. The glandular trichomes have a monocellular stalk and a
bicellular elongated head, rarely a multicellular stalk and an oval or spherical
unicellular head. The length of trichomes varies between 30 and
200 µm (1, 27, 32). In transverse section, there are tannins in the mesophyll
cells (33).
Powdered plant material
Green or brownish-green. The powder has the same microscopic characteristics
as the whole leaf (see Microscopic characteristics). The trichomes
may be broken off at the “joints”.
General identity tests
Macroscopic and microscopic examinations. Phytochemical reactions for
detection of polysaccharides and galacturonic acid (1). Thin-layer chromatography
for detection of aucubin. Visualization reagents: phloroglucinol
and hydrochloric acid (32), dimethyl benzaldehyde (34), benzidine
or anisaldehyde or vanillin-sulfuric acid reagents (35). The specific iridoids
can be valuable taxonomic markers (36).
Purity tests
Microbiological
Tests for specific microorganisms and microbial contamination limits are
as described in the WHO guidelines on quality control methods for medicinal
plant materials (37).
Chemical
No information available.
Foreign organic matter
Not more than 1% of foreign organic matter. Not more than 5% of
brownish and blackish leaves. Not more than 1% of inflorescences. Not
more than 5% of fragments of drug having a diameter less than 1 mm.
For cut drug: not more than 10% of fragments having a diameter more
than 7 mm; not more than 7% of fragments having a diameter less than
0.5 mm (1).
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