The maceration process (or Process M) is used for producing tinctures, extracts, and concentrated infusions.
It is the simplest method of crude drug extraction, which was official in I.P., 1966.
Classification
1) Simple Maceration: It is a method for preparing tinctures from organised drugs, e.g., roots, stems, leaves, etc.
2) Modified Maceration: It is a method for preparing tinctures from unorganised drugs, e.g., oleo-resins and gum resins.
3) Multiple Maceration: It is a method for preparing concentrated extracts. This method includes:
i) Double maceration, and
ii) Triple maceration.
Simple Maceration
Simple macerati on involves extraction of organised drugs having specific cell structures, e.g., roots, stems, leaves, flowers, etc.
It is a very simple method, which does not require trained operators.
Tincture of myrrh and compound tincture of benzoin are examples of products prepared by simple maceration.
Principle
In simple maceration, solid ingredients and the solvent are taken in a stoppered container, and left undisturbed for at least 3-7 days with frequent agitation.
When the soluble matter dissolves in the solvent, the resultant mixture is passed through sieves or nets.
The marc retained in the sieves is pressed, the liquids are combined, and filtered or decanted after standing.
Multiple Maceration
Multiple maceration process achieves maximum extraction by utilising the menstruum in portions for successive maceration.
However, allowance is made for the volume of menstruum retained by the marc at the end of the process. The ratio of drug to menstruum is low .