Pharmacognosy 2: Lecture 2: Family Malvaceae

When to take herbal medicine? (examples: 4)

1- At bedtime: Laxatives and sleep aids

2- At meal time: GIT disorders

3- 30 mins before mealtime: Stomachic and Liver and gall bladder remedies

4- In the morning with plenty of water: Diuretics

What are the different plant extraction methods? (examples: 3)

1- Percolation extraction

2- Digestion

3- Soxhlet extraction (aka. Continuous hot extraction method)

What is Percolation extraction?

An efficient, exhaustive pharmaceutical and phytochemical

process used to extract soluble constituents from plant

material. It involves passing a solvent (menstruum) slowly through a

column of packed, moistened raw material, allowing for

continuous extraction with unsaturated solvent, which is

often more efficient than maceration.

What is Digestion extraction?

It is also considered as maceration but, at a relatively elevated temperature. This method is suitable for hard barks or woods which are difficult for water to penetrate.

What is Soxhlet extraction?

This is the most common method used for the extraction of organic

constituents from dried plant tissue. It can be used both on laboratory and industrial scales. In the lab, the powdered material is continuously extracted in a Soxhlet apparatus with a range of solvents of increasing polarity? By boiling, condensing, and repeatedly passing fresh solvent through a sample, it maximizes extraction efficiency for analytes with limited solubility in the solvent.

What does the composition of herbal medicines depend on? (examples: 5)

1- Age and origin,

2- Harvesting period

3- The specific parts of the plant to be processed

4- The extraction methods employed

5- The drying and storage, etc. (Correct drying is the most important

phase in the whole process of production)

What is standardization?

The process of establishing quality, safety, and efficacy through

strict, consistent manufacturing, analytical, and chemical controls. It ensures consistent, documented levels of active or marker compounds. It involves establishment of reproducible pharmaceutical quality by comparing a product with established reference substances and by defining minimum amounts of one or several compounds or groups of compounds.

What are the factors of "Quality" under standardization? (examples: 3)

1- Identity : by binomial name ( not common name only ) and organ ( part used ).

2- Purity : Freedom of impurities or contaminants ( which are not allowed ).

3- Potency: % or content of the active principle.

What is the standard of "Safety" under standardization?

Proven non-toxic, through acute or chronic toxicity studies.

What is the standard of "Efficacy" under standardization?

Proven to work either through clinical studies as per FDA regulations ( U.S.A. ) or by collective evidence as per German Commission E

How is standardization of phytomedicines done? (examples: 1)

1. Ensuring that different batches contain the same specified concentration of the active principles of the marker compounds in case the exact active principles has not been determined.

Why is standardization important? (examples: 2)

1. To ensure that the therapeutic dose range is maintained

2. To avoid sub-therapeutic/toxic formulations

What is authentication and what are its requirements? (examples: 3)

The process of correct plant identification which

requires:

1- Botanical knowledge to identify the plant and the used parts.

2- Anatomical and histological knowledge (identifying characteristic

tissues or cells such as hairs, glands,...etc.)

3- Phytochemical knowledge (identifying the main active

constituents or marker compounds in the herb)

A large and diverse family of flowering plants within the order Malvales. It contains approximately 244 genera and over 4,200 species, ranging from small

herbs to massive trees. The family is most abundant in tropical and subtropical

regions.

Family Malvaceae

Family Malvaceae: Common name:

Mallow Family

Family Malvaceae: Significance: (examples: 3)

The family is highly significant in the agriculture industry:

1- Cotton (Gossypium) is the world's most important natural fiber.

2- Okra is used as food.

3- Popular garden plants like Hibiscus can be used for ornamental purposes.

Mallow leaves: Scientific Name:

Malva sylvestris

Mallow leaves: Macroscopic Features: (examples 4)

1- Alternate leaves

2- Long petioles

3- Kidney-shaped

4- Yellowish green color

Mallow leaves: Microscopic Features: (examples 2)

1- Long unicellular trichome

2- Stellate hair

Mallow leaves: Active Constituents: (examples 5)

1- (5-12%) Acidic mucilage: (mainly from glucuronic and galacturonic acids with monosaccarides rhamnose and galactose)

2- (7%) Anthocyanins (flowers)

Mallow leaves: Uses: (examples 3)

1- Demulcent Anti-tussive (non-productive cough)

2- Anti-inflammatory for alimentary canal, urinary and respiratory organs

FOLK:

3- Chest pain relief (by boiling leaves with milk)

Marshmallow leaves: Scientific Name:

Althea officinalis

Marshmallow leaves: Macroscopic Features: (examples: 3)

1- Greenish-yellow color

2- Palmate leaves

3- Mucilaginous taste

Marshmallow leaves: Microscopic Features: (examples: 3)

1- Long unicellular trichome

2- Stellate hair

3- Calcium oxalate clusters

Marshmallow leaves: Active Constituents: (examples: 2)

1- (6-10%) Acidic mucilage

2- (1.5-2.5%) Flavonoids

Marshmallow leaves: Uses: (examples: 4)

1- Demulcent anti-tussive (non-productive cough)

2- Anti-inflammatory for mouth, throat and stomach.

3- Decrease irritation

FOLK:

4- Topically applied for insect bites (bruised leaves)

Roselle/Hibiscus Flowers: Scientific Name:

Hibiscus sabdariffa

Roselle/Hibiscus Flowers: Macroscopic Features: (examples: 5)

1- Calyx: sepals have a lower prominent midrib with the

lower part fused and upper part divided into 5 long

pointed apices.

2- Epicalyx: composed of 8-12 narrow leaflets with broad

base fused with the lower part of the calyx.

Roselle/Hibiscus Flowers: Active Constituents: (examples: 7)

- (15-30%) Organic acids: Hibiscus acid, Citric acid, Malic acid, and Oxalic acid.

- (1.5%) Anthocyanins: Delphinidin and Cyanin.

- Acidic mucilage

Roselle/Hibiscus Flowers: Uses: (examples: 6)

1- Non-caffeinated refreshing drink

2- Anti-hypertensive (Adjunct therapy)

3- Mild laxative

FOLK:

4- Cholagogue

5- Diuretic

6- Antispasmodic