Pharmacognosy 2 Lecture 2: Official Seeds

Academic Year and Course Information

• Academic Year: 2024/2025
• Course: Pharmacognosy 2 (PG 203)
• Lecture Number: 2
• Lecture Topic: Official seeds
• Date: 10 October 2024

Official Seeds Lecture - Linseed

• Botanical Name: Linum usitatissimum
• Family: Linaceae
• Plant Type: Annual herb
• Cultivation Locations: Argentina, Russia, Canada, Holland, and India
• Seed Type: Anatropous
• Embryo Type: Straight
• Seed Structure: Dicotyledons
• Seed Coat Characteristics: Shiny brown, colored with yellow raphe, minutely pitted, smooth, and shining
• Seed Shape: Elongated ovate, compressed to nearly flat, rounded at one end and obliquely pointed at the other
• Seed Odor: Very slight when whole, characteristic when crushed
• Seed Taste: Mucilaginous oily taste
• Fixed Oil Content: Not less than 30%
• Foreign Organic Matter Content: Not more than 2%

Microscopical Characters of Linseed

• Testa: Large isodiametric cells, followed by 2 or 3 layers of parenchyma. Overlying a single layer of yellowish-brown narrow, longitudinally elongated sclerenchymatous cells having pitted thick lignified walls. A narrow colorless layer of collapsed cells, and hyaline layers composed of partially or completely obliterated parenchymatous cells (their long axis perpendicular to the sclerenchymatous layer). The innermost pigmented layer is formed of a single layer of polygonal flattened cells with pitted walls and reddish-brown pigments.

Chemical Composition of Linseed

• Proteins: 25%
• Fixed Oil: 30-40% (36-50% linolenic acid, 23-24% linoleic acid)
• Mucilage: 4.5-9% (mostly in the testa of the seeds)
• Cyanophoric glycoside: Linamarin

Medicinal Uses of Linseed

• Constipation Treatment: Mucilage
• Arteriosclerosis Treatment: Fixed oil (unsaturated fatty acids inhibit cholesterol synthesis)
• Anti-cancer effect: Linseed oil on tumors
• Heart Disease Protection: Omega-3 fatty acids (lower protein homocysteine levels).
• Eczema and Rheumatoid Arthritis Treatment: Poultice of whole seeds (unsaturated fatty acids)

Non-Medicinal Uses of Linseed

• Paints: Due to oxidation of unsaturated fatty acids, resulting in hardness.
• Cattle Feed: Linseed cakes (after fixed oil extraction)

Chemical Test for Linamarin

• Reagent: Diluted sulfuric acid + filter paper soaked with sodium picrate
• Procedure: Heat on water bath
• Result: Red/orange color (Guignard's test)

Cardamom Seeds

• Botanical Origin: Elettaria cardamomum Maton, Zingiberaceae Family
• Official Status: Semen cardamomi in the E.P.
• Origin Locations: Sri Lanka, Southern India, and Guatemala
• Parts: Fruits = Capsules

Active Constituents of Cardamom

• Volatile Oil: 2.8-6.2% (high proportion of terpinyl acetate and cineole) - Lost if separated from pericarp.
• Fixed Oil: 1-10%
• Starch: 50%
• Uses: Flavoring agent, condiment

Macroscopic Characters of Cardamom

• Odor and Taste: Strong aromatic, pleasant aromatic, pungent taste
• Surface: Wrinkled
• Raphe: Runs from base to apex on flat surface
• Hilum and Micropyle: Shallow depression at the apex
• Testa: Covered by arillus (colorless membrane)
• Inside: Starchy perisperm + yellowish endosperm + central small embryo

Nutmeg

• Botanical Origin: Myristica fragrans, Myristicaceae Family
• Active Constituents:
• 5-15% Volatile oil (pinene, camphene, myristicin, sabinene, other terpenes, alcohol)
• 30-40% Fat
• Starch and amylodextrin
• Phytosterol, saponin, coloring matter
• Myristicin (4% in oil): toxic, crystalline, bitter substance causing convulsions
• Uses: Stimulant and hallucinogenic (high doses), carminative, flavoring agent (low doses), external use for rheumatism.

Mace

• Origin: Dried arillus of Myristica fragrans
• Color: Bright red initially, then yellowish or orange-brown
• Active Constituents: 15% volatile oil (similar to nutmeg), macillinic and macilolic acids.
• Uses: As nutmeg.

Colchicum Seeds

• Botanical Origin: Colchicum automnale Linné, Liliaceae Family
• Active Constituents: Alkaloid colchicine (all parts of plant; 0.2-0.8% in seeds). Tropolone alkaloid, colchic-resin, glucose (5%), fixed oil (1%)
• Test for Colchicine: Yellow color with mineral acids (66% sulfuric acid).
• Uses: Relief from gout pain and inflammation, anti-leukemia (cytotoxic and anti-cancer, but also highly toxic), induces polyploidy in plant cells

Psyllium Seeds

• Botanical origin: Plantago psyllium L., Plantaginaceae
• Origin and Geographical Source: Dried ripe seeds. Plant is an annual herb native to Mediterranean countries
• Macroscopical Characteristics: Odorless; mucilaginous, slightly bitter taste. Seed shape: boat-shaped or rounded oblong; 2-3 mm long, 0.6-1.5 mm wide
• Microscopical Characteristics: Mucilaginous epidermal cells and the brow pigment layer, endospere cells with thick cellulosic pitted walls, numerous oil globules and aleurone grains
• Active Constituents: Mucilage (10%), hydrolyzing to D-xylose, L-arabinose, D-galactose, D-galacturonic acid; proteins; fixed oil
• Uses: Bulk laxative by swelling of mucilaginous seed coat and increasing volume of feces, promoting peristalsis. Purified Psyllium husk combined with various chemicals used for treating chronic constipation.
• Psyllium Husk: Most important product. Obtained by swelling seeds in water, removing the husk, and drying. Used in laxative preparations.

Explore the characteristics of official seeds, focusing on Linseed (Linum usitatissimum). This quiz covers its botanical aspects, cultivation locations, seed structure, and microscopical features. Test your knowledge on the fixed oil content and other important properties of Linseed as part of the Pharmacognosy curriculum.