Pharmacognosy 2: Lecture 3: Family Solanaceae and Scrophulariaceae

Type of herb with intermediate potency (examples: 1)

Solanaceae family herbs

Type of herb with low therapeutic index (examples: 1)

Cardiotonic herbs

Commonly known as potato family, it is an economically important family of flowering plants. It contains approximately 102 genera and between 2,500 to 2,700 species. While many members are food crops, others are known for their potent medicinal, psychotropic, or highly toxic alkaloids.

Family Solanaceae

Family Solanaceae: Food Crops: (examples: 4)

1- Potato (Solanum tuberosum)

2- Tomato (Solanum lycopersicum)

3- Eggplant

4- Peppers (Capsicum species, including bell and chili peppers).

Family Solanaceae: Industrial Crops: (examples: 1)

1- Tobacco (Nicotiana tabacum)

Family Solanaceae: Medicinal/Toxic Plants: (examples: 3)

1- Deadly Nightshade (Atropa belladonna)

2- Henbane (Hyoscyamus niger)

3- Ashwagandha (Withania somnifera)

Family Solanaceae: Common Active Constituents: (examples: 2)

Solanaceae Tropane alkaloids:

- Major: Hyocyamine (CNS stimulant followed by depression)

- Minor: Scopolamine (CNS depressant)

Family Solanaceae: Common Active Constituents Pharmacological Activity:

Tropane alkaloids have anti-cholinergic activity (parasympatholytic)

Family Solanaceae: Common Uses: (examples: 5)

1- Antispasmodic in G.I cramps (relaxes smooth muscles).

2- Pre-anaesthetic medication (to decrease saliva and respiratory secretions).

3- Mydriatic effect (eyedrops) (Atropine (levo isomer))

4- Sedative and hypnotic (Scopolamine)

5- Anti-emetic motion sickness (Scopolamine)

Family Solanaceae: Side Effects and Contraindicated: (examples: 3)

1- Blurred vision from mydriasis (atropine) countered by pilocarpine

2- Higher doses causes CNS depression and hallucinations

3- Contraindicated in Glaucoma

Belladonna leaves: Scientific Name:

Atropa belladonna

Belladonna leaves: Macroscopic Features: (examples: 12)

- Irregular grayish-green matted leaf with entire margin, glabrous surface, and pubescent vein on the lower surface.

- Hollow longitudinal stem

- Solitary flower with yellowish-purple corolla

- Tobacco-like odor

- Bitter taste

Belladonna leaves: Microscopic Features: (examples: 5)

1- Anisocytic stomata in lower epidermis

2- Solanaceae Glandular hair (unicellular stalk and multicellular head)

3- Glandular trichome with multicellular stalk and unicellular head

4- Epidermal cells with striated cuticle

5- Idioblasts with microcrystals of calcium oxalate

Stramonium leaves: Scientific Name:

Datura Stramonium

Stramonium leaves: Macroscopic Features: (examples: 11)

- Irregular matted petiolated lobed leaf with acuminate apex and asymmetric base and grayish green to olive green color

- Cylindrical longitudinal stem

- Funnel shaped corolla

- Narcotic odor

- Nauseous taste

Stramonium leaves: Microscopic Features: (examples: 5)

1- Anisocytic stomata on both upper and lower epidermis

2- Solanaceae Glandular hair (unicellular stalk and multicellular head)

3- Non glandular trichomes: multicellular, uniseriate

4- Densely warty cuticle

5- Clusters of Ca2+ oxalate (layer under the palisade)

Used as source of hyoscyamine-6-hydroxylase enzyme, the key enzyme in the conversion of hyoscyamine into scopolamine for biotechnological application.

Leaves of other Datura species (such as, D. metel, D.innoxia and D. which fastusa contain Solanaceae alkaloids with scopolamine (major) and hyoscyamine (minor))

Egyptian Henbane: Scientific Name:

Hyocyamus muticus

Egyptian Henbane: Macroscopic Features: (examples: 10)

- Green to yellow succulent lobed leaves with flattened petiole and midrib.

- Solid succulent stem

- Funnel shaped corolla and calyx in tube

- Characteristic odor

- Bitter taste

Egyptian Henbane: Microscopic Features: (examples: 4)

1- Anisocytic stomata on both upper and lower epidermis

2- Solanaceae Glandular hair (unicellular stalk and multicellular head)

3- Branched and non-branched glandular trichomes (multicellular uniseriate branched stalk and unicellular head)

4- Prisms and twin prisms of Ca2+ oxalate

European Henbane: Scientific Name:

Hyoscymus niger

European Henbane: Macroscopic Features: (examples: 7)

- Green to grayish ovate lanceolate leaves

- Hollow cylindrical and longitudnal stem

- Tubular calyx

- Characteristic odor

- Bitter taste

European Henbane: Microscopic Features: (examples: 4)

1- Anisocytic stomata on both upper and lower epidermis

2- Solanaceae Glandular hair (unicellular stalk and multicellular head)

3- Glandular trichomes with multicellular uniseriate stalk and multicellular head

4- Prisms and twin prisms of Ca2+ oxalate

Scrophulariaceae Family: Common Uses: (examples: 1)

1- Congestive heart failure

Scrophulariaceae Leaves: Common Notes: (examples: 1)

1- Very narrow therapeutic index-should be prescribed with individualized dose

Common Foxglove: Scientific Name:

Digitalis purpurea

Common Foxglove Leaves: Macroscopic Features: (examples: 6)

1- Crumpled broken fragments

2- shape from ovate-lanceolate

3- obtuse or rounded apex

4- winged petiole

5- Characteristic odor especially when moistened

6- Very bitter taste

Common Foxglove Leaves: Microscopic Features: (examples: 5)

1- Upper Epidermal cells: nearly straight walls with no stomata

2- Lower Epidermal cells: sinuate walls with anomocytic stomata

3- Digitalis glandular hair (unicellular stalk & bicellular head)

4- Glandular trichomes with multicellular uniseriate stalk and monocellular head

5- Non glandular trichomes: multicellular, uniseriate with lightly warty cuticle

Common Foxglove Leaves: Active Constituents: (examples: 7)

- Cardiac Glycosides: Purpurea glycoside A (Digitoxin/Digitoxigenin), Purpurea glycoside B (Gitoxin/Gitoxigenin)

(Digilanidase Enzyme breaks purpurea glycosides into glycone and aglycone)

- Saponins (steroidal): digitonin

Common Foxglove Leaves: Active Constituents Pharmacological Activity:

Cardiac glycosides act as Na+/ K+ ATP-ase inhibitors:

- An increase in Na+ and decrease of K+ in the cell

stimulates secondary Na+ Ca++ exchange

mechanism that functions to remove intracellular

Na+ with subsequent increase intracellular Ca++.

- Ca++ interacts with troponin, allowing for the

formation the contractile protein actomyosin.

Hence, this increase myocardial contractility (positive ionotropic) and decrease pulse cardiac rate (negative chronotropic).

Woolly Foxglove: Scientific Name:

Digitalis Lanata

Woolly Foxglove Leaves: Macroscopic Features: (examples: 5)

1- Elongated leaves

2- Entire margin

3- Parallel venation

4- Characteristic odor especially when moistened

5- Very bitter taste'.

Woolly Foxglove Leaves: Macroscopic Features: (examples: 2)

1- Epidermal cells have more anomocytic stomata on the lower surface than the upper surface

2- Digitalis glandular hair (unicellular stalk & bicellular head).

Common Foxglove Leaves: Active Constituents: (examples: 6)

- Cardiac glycosides: Lanatoside A (aglycone digitoxigenin), Lanatoside B (aglycone gitoxigenin), Lanatoside C (aglycone digoxigenin)

(Lanatosidase Enzyme breaks lanata glycosides into glycone and aglycone)

Common Foxglove: Macroscopic Features: