Medicinal Plants and Their Uses

Active Ingredients in Plants

• Active ingredients are found in various parts of plants.
• Parts include leaves, flowers, seeds, herbs, bark, fruits, wood, and underground parts.
• These parts are extracted and separated to isolate active ingredients for medicinal and pharmaceutical use.

Senna

• Common name: Indian Senna or Alexandrian Senna
• Biological source: Dried leaflets of Cassia acutifolia (Alexandrian Senna or Eyptian senna) and Cassia angustifolia (Indian Senna).
• Family: Leguminosae
• History: Used in European medicine since the 9th or 10th century.
• Origin: Introduced to Egypt from Mecca, then cultivated in Egypt and India.
• Morphology: Perennial shrubs, about 1m-1.5m tall, yellow flowers, form legumes (pods).
• Color: Greyish green
• Odor/taste: Distinct bitter, mucilaginous
• Shape: Ovate, Lanceolate
• Chemical constituents: Sennosides A and B (anthraquinone glycosides)
• Uses: Strong laxative, used for acute or chronic constipation, or when required soft stool (in medical procedures like abdominal operations, anal-rectal operations, hemorrhoids, x-ray).

Digitalis Leaves

• Common name: Purple foxglove
• Biological source: Dried leaves of Digitalis purpurea and Digitalis lanata.
• Family: Scrophulariaceae
• History: Cardio-active or cardio tonic drug, used in the treatment of heart conditions since 1775.
• Origin: Southern and Central regions of Europe.
• Morphological characters: Biennial, rarely perennial; Ovate or Lanceolate shape; Dentate margin; Anastomosing venation; Alternate arrangement.
• Chemical constituents: Purpurea glycoside A, Purpurea glycoside B (which hydrolyze to digitoxin and gitoxin)
• Uses: Treatment of Congestive Heart Failure (CHF) and Arrhythmia.

Henna

• Common name: Eyptian privet, Lawsonia alba
• Biological Source: Dried leaves of Lawsonia inermis.
• Family: Lythraceae
• Origin: Africa, southern Asia, and northern Australia
• Chemical constituents: A red/orange dye molecule Lawsone (naphtaquinone); gallic acid, tannins, and sugars
• Uses: Natural hand and hair dyes, antifungal, tanning (astringent).

Coca Leaf

• Common name: Coca
• Biological source: Dried leaves of Erythroxylon coca.
• Family: Erythroxylacence.
• Origin: South American countries like Peru and Bolivia.
• Morphological characters: Glabrous shape; Entire margin; Prominent midrib at lower surface; Prism type calcium oxalate crystals in upper epidermis; trichomes absent.
• Chemical constituents: Cocaine and cinnamyl cocaine.
• Uses: Local anesthetic for eyes and ears.

Datura Stramonium

• Common name: Thorn Apple
• Occurrence: Dried leaves and flowering tops of various Datura species (Datura stramonium, Datura innoxia, Datura metel, Datura sanguinea)
• Origin: India, England, other tropical and subtropical regions
• Morphology: Light olive brown in color; Dentate margin; Acuminate apex
• Chemical constituents: Hyoscyamine (main), Hyoscine, Atropine (in lesser amount)
• Uses: Stimulant on CNS; Depresses nerve endings on secretory glands and smooth muscle; Used in ophthalmic practice for decrease of sweating and asthma.

Hyocyamus Niger

• Common name: Henbane, Poison tobacco
• Occurrence: Dried leaves and flowering tops.
• Allied drugs: Hyocymus muticus, H. reticulus, H. aureus
• Chemical constituents: Hyoscyamine (main - 75%), Hyoscine, Atropine (less)
• Morphological characters: Sessile leaves; Irregularly-dentate margin; Acute apex; Broad midrib and flat

Atropa Belladonna

• Common name: Deadly nightshade.
• Occurrence: Dried leaves and flowering tops of Atropa belladonna.
• Chemical constituents: Hyoscyamine (main), Hyoscine (less), Atropine (Main)
• Uses: Parasympathetic and anticholinergic properties; Used as antidote for opium and chloral hydrate poisoning

Eucalyptus Leaves

• Occurrence: Fresh leaves of Eucalyptus globulus; Young plants have sessile and cordate leaves; Mature plants have petiolated and ovate/lanceolate leaves.
• Chemical constituents: Cineol and Eucalyptol
• Uses: Nasopharyngeal infection treatment; Cough and decongestant.

Cinnamon Bark

• Common name: Dalchini, Cortec cinnamomi
• Biological source: Dried inner bark of Cinnamomum zeylinicum.
• Family: Lauraceae
• Origin: Sri Lanka and Malabar coast of India; Also cultivated in other regions.
• Collection: Bark collected from six-year-old trees.
• Morphological characters: Smooth, splinter-like, Pericyclic fibres, outer and inner surface characteristics.
• Chemical constituents: Cinnamaldehyde, eugenol
• Uses: Flavoring agents, carminative, various dental preparations, candy and perfumes.

Cinchona Bark

• Common name: Peruvian bark, Jesuit's bark.
• Biological source: Dried stem and root bark of Cinchona species (calisaya, officinale, succirubra, ledgeriana).
• Family: Rubiaceae
• Chemical constituents: Quinine, Quinidine, Cinchonin, Cinchonidin.
• Origin: Indigenous to South America, cultivated in other regions.
• Uses: Treatment of malaria and cardiac arrhythmias.

Frangula Bark

• Common name: Frangula alnus
• Biological source: Dried bark of Rhamnus frangula.
• Family: Rhamnaceae
• Origin: Native to Europe, northernmost Africa, western Asia, Ireland, and Great Britain.
• Morphological characters: Curved or channeled; Outer surface rough with silvery patches of lichen; Inner surface yellow to reddish brown; Striations; Slightly bitter taste.
• Chemical constituents: Anthraquinone glycoside: Frangulin
• Uses: Purgative and laxative

Cascara Bark

• Common name: Sagrada, Sacred Bark
• Biological source: Dried stem bark of Rhamnus purshiana.
• Family: Rhamnaceae
• Origin: Cultivated in North California, Washington, Oregon, and Kenya.
• Morphological characters: Quills / channeled; Outer surface smooth; Silvery patches of lichen; Inner surface yellow/reddish brown; Striations; Bitter taste.
• Microscopical characters: Cork consists of numerous layers; Cortex consists of flattened collenchyma and cellulosic/parenchyma.
• Chemical constituents: Anthraquinone glycosides and Cascarosides
• Uses: As a laxative; bitter tonic (small doses)

Quillaja Bark

• Common name: Soap bark, Panama wood.
• Biological source: Dried inner bark of Quillaja saponaria.
• Origin: Indigenous to South America (especially Chile and Peru).
• Morphological characters: Flat pieces; Outer surface is pale-brown or yellowish-white; Longitudinally striated; Inner surface is white/yellowish-white; Smooth, very hard; Odorless; Acrid taste.
• Chemical constituents: Saponin (Quiillaic acid)
• Uses: Emulsifying agent in external preparations with tars and volatile oils.

Quassia Wood

• Biological source: Dried stem wood of Picrasma excelsa.
• Family: Simaroubaceae
• Origin: Jamaica.
• Macroscopical characterizations: Rasping or chips up to 30 cm in diameter; Initially whitish, but turns yellow on exposure, showing black markings due to fungus.
• Odor/Taste: Odorless; Very bitter.
• Chemical constituents: Quassin, neoquassin, isoquassin.
• Uses: Bitter tonic and insecticide.

Sandalwood

• Biological source: Heartwood of Santalum album.
• Family: Santalaceae
• Origin: India and Malaysia.
• Microscopical characters: Pale yellow; Characteristic odor; Unpleasant taste.
• Chemical constituents: a-Santalol, β-Santalol
• Uses: Symptomatic treatment of dysuria; Perfumes, cosmetics, incense sticks.

The Wood

• Sapwood (outer): Lighter in color, living, retains food, functions as conductive and supporting tissues.
• Heartwood (inner): Darker, dead, no water transport now, filled with resins, tannins and colored matters.

The Flower

• Definition: Morphologically a compressed determinate fertile shoot crowded with modified leaves specialized for reproduction.

Clove

• Synonyme(s): Laung, Clove bud, Caryophylli
• Biological source: Dried ripe fruit bud of Eugenia caryophyllus.
• Family: Myrtaceae
• Morphology: Perennial tree; Buds collected when they change color to crimson red; 15-20mm long, 2-3mm diam; Dome-shaped corolla, thick-walled spreading sepals; Sub-cylindrical hypanthium, tapering end; Aromatic odor, pungent taste
• Chemical constituents: Eugenol, Caryophyllene, d-Acetyl eugenol
• Uses: Condiment; Carminative; Antiseptic; Dental filling material/anesthetic

German Chamomile

• Biological source: Dried expanded flower heads of Matricaria chamomilla.
• Family: Asteraceae
• Origin: Widely introduced, found all over Europe and western Asia; now present in North America and Australia.
• Morphology: Dried, terminal flower head (10-20mm diam); Prominent yellow disk flowers and silver-white ray flowers; Flowers in June and July.

Pyrethrum

• Common name: Persian insect flower
• Biological source: Dried expanded flower heads of Chrysanthenum cinerariifolium.
• Family: Asteraceae
• Active constituents: Pyrethrin, Cinerin, Jasmolin, Chysanthemic acid
• Uses: Insecticidal; For scabies; Causes abortion, caution.

Test your knowledge on various medicinal plants, their active ingredients, and common uses. This quiz covers important plants like Senna, Digitalis, and Henna, along with their historical background and chemical constituents. Enhance your understanding of herbal medicine and its applications.