Extraction Methods and Principles

A comprehensive set of vocabulary flashcards covering the definitions, methods, and technical terms associated with the extraction of medicinal components from plant or animal tissues.

Extraction

The method of removing active constituents from insoluble residues (solid or liquid) by treatment with a liquid solvent to separate medicinally active portions from inactive components.

Menstruum

The selective solvent used during the extraction process to dissolve wanted components.

Marc

The undissolved part or solid residue that remains after the extraction process is complete.

Extract

Preparations of crude drugs which contain all the constituents that are soluble in the solvent used.

Dry extract

A type of extract preparation used specifically for tablets and capsules.

Soft extract

A type of extract preparation used for ointments and suppositories.

Liquid extract

A type of extract preparation such as a tincture.

Liquid-Liquid Extraction

Also known as solvent extraction, it involves the separation of components from a liquid mixture based on their unequal distribution between two immiscible liquids.

Solid-liquid Extraction

Also known as leaching, it is the removal of constituents from a mixture of solids by bringing the solid material into contact with a liquid solvent.

Maceration

An extraction procedure where coarsely powdered plant material is placed in a closed container with menstruum for at least $3$ days with periodic stirring or shaking.

Micelle

The extract solution separated from the marc after filtration in the maceration process.

Thermolabile compounds

Compounds that are sensitive to heat; maceration is a suitable extraction method for these substances because it does not require high temperatures.

Soxhlet apparatus

A piece of laboratory equipment used for continuous extraction, consisting of a distillation flask, Soxhlet extractor, and a reflux condenser.

Thimble

A component of the Soxhlet apparatus, typically made of cellulose, where the source material intended for extraction is placed.

Supercritical fluid (SCF)

A material used in a state above its critical temperature and critical pressure where gas and liquid phases coexist, possessing liquid-like density and gas-like transport properties.

Critical point

The specific temperature and pressure at which the density of the gas and liquid phases is the same and there is no distinction between the phases.

Carbon dioxide ($CO_2$) as SCF

The most used supercritical fluid, characterized by a critical temperature of $304.1\,K$ and a critical pressure of $73.8\,bar$.

Ultrasound-assisted extraction

An effective and fast extraction method using ultrasonic waves with a frequency of more than $20,000\,Hz$ that does not generate heat.

Cavitation bubbles

Bubbles generated by ultrasound in a solvent that disrupt plant cell walls upon collapsing, thereby increasing solvent penetration and accelerating the release of compounds.