Convectional/traditional extraction methods.

Methods	Process	Advantages	Disadvantages	References
Squeezing	The techniques involve the application of pressure on moistened plant samples via pestle, mortars, mullers, presses, etc., on the plant samples to get the extrudate	Simple	Possibility of contamination of bio-actives	59–61
		Little or no solvent required
		Requires no thermal degradation
		Low extraction efficiency
Maceration	Powdered plant samples are added to the solvent already in a stoppered container with frequent agitation. The aqueous extracting solvent is then drained off followed by pressing and centrifugation to remove the remaining miscella from the plant material	Can be used for a large amount of sample	Long extraction duration	39, 62 and 63
		A limited solvent is required
		Long extraction time	Only useful for soluble or thermolabile bio-actives
		Low extraction efficiency
Decoction	The plant matrix comes in contact with the aqueous solvent at boiling point for a maximum duration of 30 min. The liquid is then filtered at end of the extraction. Then the liquid is filtered, and the squeezed liquid of the extracted matrix impregnated with the aqueous solvent is added to it	Use predominantly for phenolics	Only useful for thermoresistant bioactive	64–66
		Requires moderate heat	Limited validity
		Long extraction time	Extracts have a short shelf life
		Low extraction efficiency
Infusion	Extraction in this regard involves soaking the solid plant powder in cold or boiling water for a short time	Long extraction time	Easily altered extract	4 and 67
		Low extraction efficiency	Limited validity
Percolation	The method makes use of narrow shaped percolator which holds the moistened plant samples. The plant material is then rinsed with the solvent several times until the active ingredient is extracted	Easy to operate	Good grinding required	68–70
		Very fast	Requires preliminary humidification
			Not exhaustive