Page 111 - Pharmacognosy 2 PG303 (1)

Pharmacognosy-2 (PG303) Level 2 Clinical Pharmacy-Pharm D

Powder
Powdered lobelia is green in color with a slight irritant odor and slight then burning and
acrid taste, it is characterized microscopically by the presence of the following diagnostic
elements.
1- Non- glandular trichomes, conical, unicellular with lignified walls and warty or streaked
cuticle.
2- Fragments of leaf showing beaded papillosed epidermal cells, anomocytic stomata and
non- glandular conical trichomes.
3- Fragments of lamina in T.S. showing the dorsiventral structure.
4- Vein islets without any calcium oxalate crystals.
5- Brown testa showing the characteristic thick- walled, lignified epidermal cells.
6- Pollen grains are nearly spherical with 3 pores and smooth or faint, warty exine.
7- Fibrous layer of anther.
8- Lignified pitted pith parenchyma.
9- Irregular lignified sclerides of mesocarp.

Constituents
- alkaloids (up to 0.6%) of piperidine type, lobeline (major alkaloid0, lobelanine,
lobelanidine, isolobelanine and lobelidine.
- Other constituents are inflatin, lobelic acid, wax and resin.

Uses
1- In bronchial asthma as it relaxes the bronchial muscles.
2- Respiratory stimulant, used in dyspnea of chronic bronchitis.
3- As an expectorant and diaphoretic.
4- Used as smoking-detergent in the form of lozenges as it has nicotine like action, first excites
the nerve cells and then paralyses them.

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