[PCOG-LAB-FIN-03-PT2] EXTRACTION AND PHYTHOCHEMICAL ANALYSIS OF MEDICINAL PLANTS

THIS FLASHCARDS IS ABOUT [PCOG] 8 GENERAL TECHNIQUES OF MEDICINAL PLANT EXTRACTION.

Plant Tissue Homogenization

Mechanical disruption of plant cells (e.g., grinding/blending) in a solvent to release intracellular phytochemicals rapidly.

1. Fine particles

2. 5-10 minutes

3. 24 hours

4. Filtrate

5. Reduced pressure

6. Centrifuged

Plant Tissue Homogenization:

• Dried or wet, fresh plant parts are grinded in a blender to (1)___ particles along with certain quantity of solvent

• Shake vigorously for (2)____ minutes or left for (3)___ hours after which the extract is filtered

• The (4)____ is dried under (5) reduced ____ and redissolved in the solvent or (6)_____ for clarification of the extract.

Maceration

Soaking coarse or powdered plant material in a solvent at room temperature for an extended period with occasional agitation to dissolve constituents.

1. Whole/coarsely powdered crude drug

2. Room temperature

3. 3 days

4. Marc

5. Filtration or decantation

Maceration:

• (1)________ powdered crude drug is placed in a stoppered container with the solvent

• Allow to stand at (2)_____ temperature for a period of at least (3)__ days with frequent agitation until the soluble matter gets dissolved

• The mixture then is strained, the (4)____ (the damp solid material) is pressed

• The combined liquids are clarified by (5)____ or _____ after standing

Infusion

Extraction by steeping plant material (usually soft tissues like leaves/flowers) in hot or cold water for a short time (similar to making tea).

1. Fresh infusion

2. Macerating the crude drug

3. Cold or boiling water

4. Dilute solutions

Infusion:

• (1)____ infusions are prepared by (2)_____ the crude drug for a short period of time with (3)____ or _____ water

• These are (4)_____ solutions of the readily soluble constituents of crude drugs

Digestion

A form of maceration performed at elevated temperatures to increase solubility and extraction rate of compounds.

1. Maceration

2. Gentle heat

3. Menstruum

Digestion:

• A form of (1)_____ in which (2)____ heat is used during the process of extraction

• Used when moderately elevated temperature is not objectionable

• The solvent efficiency of the (3)_____ is thereby increased

Decoction

Boiling hard plant materials (e.g., roots, bark) in water for a prolonged time to extract heat-stable constituents.

1. 1:4

2. 1/4th the original

3. Water-soluble and heat-soluble constituents

4. Ayurvedic extracts

Decoction:

• The crude drug is boiled in a specified volume of water, (1)___ for a defined time

• Volume is reduced to (2)___ the original

• Cooled and strained/filtered

• Suitable for extracting (3)____ and ____ constituents

• Typically used in the preparation of (4)____ extracts

Percolation

Continuous downward flow of solvent through a packed column of plant material, allowing efficient and exhaustive extraction.

1. Fluid extracts

2. Solid ingredients

3. Specified menstruum

4. 4 hours

5. Percolator

6. Macerate

7. 24 hours

8. Percolate

9. Three-quarters

10. Marc

11. Mixed liquid

12. Filtration

13. Decanting

Percolation:

• Used most frequently to extract active ingredients in the preparation of (1)____ extracts

• The (2)____ ingredients are moistened with an appropriate amount of the (3) specified _____

• Allowed to stand for approximately (4)__ hours in a well-closed container. After stand time, the mass is packed and the top of the (5)_____ is closed

• The mixture is allowed to (6)_____ in the closed percolator for (7)__ hours

• Additional menstruum is added as required, until the (8)_____ measures about (9)______ of the required volume of the finished product

• The (10)____ is then pressed and the expressed liquid is added to the percolate

• Sufficient menstruum is added to produce the required volume

• The (11)____ liquid is clarified by (12)____ or by standing followed by (13)_____.

Maceration

What is the heart of extraction processes of medicinal plants?

Soxhlet Extraction (Hot Continuous Extraction)

Automated cyclic extraction where solvent is repeatedly vaporized, condensed, and passed through the sample, ensuring thorough extraction.

1. Thimble

2. Soxhlet apparatus

3. Extracting solvent

4. Condensed extractant

5. Siphon tube

6. Residue

Soxhlet Extraction (Hot Continuous Extraction):

• The finely ground crude drug is placed in a porous bag or “(1)____” (made of strong filter paper), which is placed in the (2)_____ apparatus

• The (3)_____ solvent in flask is heated, and the vapors condense in condenser

• The (4)_____ extractant drips into the thimble containing the crude drug

• When the level of liquid in chamber rises to the top of (5)_____ tube, the liquid contents of chamber siphon into flask

• This process is continuous and is carried out until a drop of solvent from the siphon tube does not leave (6)_____ when evaporated.

Thimble

This is made of strong filter paper.

Info

The effect of extracted plant phytochemicals depends on:

1. The nature and origin of the plant material

2. Degree of processing

3. Moisture content

4. Particle size

Info

Variation in Extraction Methods:

1. Length of the extraction period

2. Solvent used

3. pH of the solvent

4. Temperature

5. Particle size of the plant tissues

6. Solvent-to-sample ration