Database on medicinal plants used in ayurveda - AYUSH Research ...

PHARMACOGNOSY
Macroscopic
Root – Cylindrical, unbranched, available in cut pieces of varying length and
0.5-3 cm thick, externally yellow to buff colour with dark brown patches on
the cork; outer surface marked with prominent longitudinal ridges, furrows
and transverse cracks; bark easily separable from wood; fracture short and
granular in bark region and fibrous in wood; odour distinct but unpleasant;
taste slightly bitter (Anonymous, 1999; Prasad et al., 1961).
Microscopic
Transverse section of root shows a cork, composed of 15-25 layers of thinwalled,
tangentially elongated, rectangular cells, some filled with reddishbrown
content; secondary cortex composed of an outer region of broken ring
of stone cells of varying thickness followed by wide zone of oval to
polygonal parenchymatous cells; stone cells yellow in colour, of variable
shape and size mostly round, oval to polygonal or linear; secondary phloem
composed of mostly parenchyma with small patches of sieve elements and
small strands of stone cells, similar to those present in secondary cortex; resin
cells present irregularly in this region; phloem fibres absent; phloem rays 1-3
cells wide; secondary xylem segmented and shows a wedge-shaped structure;
consisting of small tangential concentric bands of unlignified masses of
parenchymatous tissue; separated by similar concentric band of lignified
tissue, composed of vessels, tracheids, fibres, fibretracheids and xylem
parenchyma; in isolated preparation xylem vessels cylindrical to oblique with
transverse articulations, vary in shape and size, with bordered pits; fibres
much elongated with mostly tapering ends and pitted walls; thick-walled and
lignified parenchyma possess simple and bordered pits and scalariform
thickening; tracheids are narrower with tapering ends and some of them are
elongated and irregular in shape with small projection from their margin,
xylem fibres are narrow, wavy and pitted. Xylem rays not distinctly marked
where adjoining parenchyma are delignified; rosette and a few prismatic
crystals of calcium oxalate and abundant starch grains present in
parenchymatous tissue; starch grains simple, elliptical to spherical with
central hilum, 5.5-22 ��diam, compound grains having 2-3 or rarely upto 6
components (Anonymous, 1999; Raghunathan and Mitra, 1982; Prasad et al.,
1961).
Powder microscopy
Root- powder light brown in colour; shows a number of stone cells, xylem
fibres, tracheids, fibre-tracheids, vessels with pitted walls, fragments of cork,
rosette and prismatic crystals of calcium oxalate, simple and compound
starch grains measuring. 5.5-22� in diameter (Anonymous, 1999).
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