This section is from the book "A Text Book Of Materia Medica, Being An Account Of The More Important Crude Drugs Of Vegetable And Animal Origin", by Henry G. Greenish. Also available from Amazon: A Text Book of Materia Medica : Being an Account of the More Important Crude Drugs of Vegetable and Animal Origin.
The official myrobalans, which are properly termed black chebulic myrobalans, are the dried immature fruits of Terminalia Chebula, Retzius (N.O. Gombretaceoe), a large tree abundant in northern India. The fruits are collected at varying stages of development. If collected when about the size of a raisin and dried they constitute the official drug; if allowed to grow to the size of a walnut they form the valuable tanning material known commercially as chebulic myrobalans or simply myrobalans.
Black chebulic myrobalans are dark brown or nearly black in colour, ovoid or fusiform in shape and from 10 to 30 mm. or more in length and 5 to 15 mm. in width; they are much shrivelled longitudinally, hard and brittle; the fracture is dark and shiny and in the centre there is often a small cavity; they have no odour but a very astringent taste.
The fruits contain from 20 to 30 per cent, of a mixture of gallic acid and tannic acid, apparently derived from an organic acid, chebulinic acid; they contain also a greenish oleo-resin which has been termed myrobalanin.
Notwithstanding the large proportion of tannin they contain black chebulic myrobalans, taken internally, act as an efficient purgative. They are also used externally as an astringent in the place of galls.
Commercial myrobalans are the fruits collected when about the size of a walnut and dried; they are oval, pointed at each end, brownish or greenish yellow in colour and ribbed. They contain about 40 per cent, of tannin and are imported in large quantities for use in tanneries.