Pharmacognostic Features of Coriander (Coriandrum sativum) and Caraway (Carum carvi)



1. Botanical Source:

  • Coriander (Coriandrum sativum): A herb from the Apiaceae family, primarily grown for its leaves and seeds.
  • Caraway (Carum carvi): Also from the Apiaceae family, cultivated for its seeds used as a spice and medicinally.

2. Morphological Characteristics:

  • Coriander:
    • Leaves: Bipinnately or tripinnately compound, bright green, smooth, and aromatic.
    • Flowers: Small, white or pinkish, in compound umbels.
    • Fruit: Globular schizocarp (commonly referred to as seeds), aromatic, with a slightly ridged surface.
    • Seeds: Small, brownish-yellow, with two mericarps, having a mild citrusy, earthy aroma.
  • Caraway:
    • Leaves: Finely divided, feathery, alternate, dark green, resembling ferns.
    • Flowers: Small, white, in compound umbels, with a five-petaled structure.
    • Fruit: Crescent-shaped schizocarp (commonly called seeds), with five pale ridges.
    • Seeds: Brown, curved, elongated, with a strong, anise-like aroma.

3. Microscopical Characteristics:

  • Coriander:
    • Cells of the seed coat show characteristic ridged patterns.
    • Presence of volatile oil sacs in the epidermal layer.
    • Testa cells are polygonal.
  • Caraway:
    • Oil ducts (vitamin ducts) are prominently visible.
    • Epidermal cells have beaded thickenings and polygonal outlines.
    • Presence of crystal sheath surrounding the vascular bundle.

4. Organoleptic Properties:

  • Coriander:
    • Odor: Mild, sweet, and citrus-like.
    • Taste: Mildly spicy and slightly sweet.
    • Color: Brownish-yellow.
    • Texture: Hard and slightly ridged.
  • Caraway:
    • Odor: Pungent, spicy, with an anise-like aroma.
    • Taste: Sharp, spicy, with a warm flavor.
    • Color: Brown with a pale ridge.
    • Texture: Crescent-shaped and ridged.

5. Phytochemical Constituents:

  • Coriander:
    • Essential oils: Linalool, pinene, and geraniol.
    • Flavonoids: Quercetin and kaempferol.
    • Fatty acids: Oleic and linoleic acids.
    • Coumarins and phenolic compounds.
  • Caraway:
    • Essential oils: Carvone (dominant), limonene.
    • Flavonoids and tannins.
    • Fatty oils: Oleic, linoleic, and petroselinic acids.
    • Volatile compounds: Terpenoids.

6. Powder Characteristics:

  • Coriander Powder: Pale brownish powder with a slightly bitter taste. Presence of polygonal seed coat cells and volatile oil sacs.
  • Caraway Powder: Dark brown powder with a strong spicy smell, visible oil ducts, and characteristic crescent-shaped fragments.

7. Chemical Tests:

  • Coriander:
    • Test for essential oils: Distillation method to identify linalool.
    • Flavonoid test: Shinoda test for the presence of quercetin.
  • Caraway:
    • Test for carvone: Sodium hydroxide test produces a pink to red coloration.
    • Distillation method for essential oil analysis.

8. Therapeutic Uses:

  • Coriander:
    • Digestive aid, anti-inflammatory, and used to alleviate gastrointestinal complaints.
    • Exhibits antimicrobial and antioxidant properties.
  • Caraway:
    • Carminative, aids in digestion, and relieves bloating.
    • Antispasmodic, antimicrobial, and antioxidant.

9. Adulteration Detection:

  • Coriander: May be adulterated with similar-looking seeds like dill; checked by taste and chemical composition.
  • Caraway: Commonly adulterated with cumin seeds; distinguished through shape, aroma, and chemical tests (e.g., carvone test).

10. Storage:

  • Coriander: Stored in a cool, dry place away from light to preserve volatile oils.
  • Caraway: Needs airtight containers to prevent volatile oil loss and degradation.

Both plants are widely used for their culinary and medicinal properties, and their pharmacognostic evaluation ensures proper identification and quality control.