Page 102 - Medicinal Plants_PharmD general

Ergastic Cell Contents

The cell contents with which we are concerned in pharmacognosy
are those which can be identified in vegetable drugs by microscopical
examination or by chemical and physical tests. These cell contents are
referred as ergastic, being non –living (non-protoplasmic) materials. These
ergastic materials are found in cytoplasm and vacuole.
Ergastic cell inclusions are:
1. Primary metabolites or food reserves or food storage products:

are compounds that are directly involved in the growth and
development of a plant. They include carbohydrates, proteins and
lipids.
2. Secondary metabolites or by-products of metabolism: are
compounds produced in other metabolic pathways that, although
important, are not essential to the functioning of the plant. However,
secondary plant metabolites are useful in the long term, often
for defense mechanisms. The basic metabolic pathways constitute
the origins of secondary metabolism giving rise to compounds some
of which are responsible for the characteristic odour, pungencies and
colours of plants; other gives a particular plant its medicinal or
poisonous virtues. They include alkaloids, glycosides, volatile oils,
resins, tannins, calcium oxalates, silica ….etc.

Figure 33. Ergastic cell contents

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