Pharmacognostic Importance of Epidermis - All Global Updates

Pharmacognostic Importance of Epidermis

·         Leaves offer diagnostic characteristics which serve in quality control of leaf drugs

§  Shape, size and wall structure of the epidermal cells

§  Straight –walled epidermal cells are found in medicinal plants such as coca and Senna leaves

§  Wavy-walled epidermal cells are in found in Datura stramonium, Hyoscyamus niger and Atropa belladonna.

§  Form, distribution and relation to epidermal cells of the stomata

§  Stomata are classified on the basis of subsidiary cells into;

·         Anomocytic Stomata

o   When cells surrounding the stomata resemble other epidermal cells

·         Anisocytic stomata

o   Stoma is surrounded by three or four subsidiary cells one of which is markedly smaller than others

·         Paracytic stomata

o   Two subsidiary cells with their long axes parallel to the pore

·         Diacytic stomata

o   Two subsidiary cells with their long axis at right angle to the pore of the stomata

o   Variations among anisocytic, paracytic and diacytic types of stomata:

·         Actinocytic type

o   Subsidiary cells are arranged along the radii of a circle

§  Form, distribution and abundance of epidermal trichomes

§   Trichomes offer physical and chemical protection from microbes, aphids and insects.

§  Types of trichomes are characteristic of a plant family or genus

§  Clothing trichomes –cover surface of the leaf

§  Glandular trichomes –may be unicellular or multicellular (they store ergastic/drug substances)

·         Multicellular trichomes may be;

o   Uniseriate, biseriate, multiseriate or complicated branched structures

Green Leaves

Expert in Digital Marketing, Content Creator, and Website Developer.