Page 223 - PG 101-Course notes مذكرة النظري 24-25 with spec

Medicinal plants (PG 101) Level 1 Clinical Pharmacy-PharmD

Time of the day: It has been found that not only the season of the year, but also the

time of the day would affect the active constituents of drugs e.g. digitalis leaves (the

cardiac glycosides are maximum afternoon) and the solanaceous leaves (the

alkaloids are maximum afternoon), the volatile oil containing plants are collected

in the morning.

2- Stage of the development of the plant:

• The percentage of the active constituents of drugs depends on the stage of

maturity and age of the plant, e.g., solanaceous leaves and santonica flowers

are collected from mature plants. Poppy capsules are incised for opium

collection when they are fully grown but still unripe; contains the highest

concentration of morphine.

Collection of leaves: Generally, they are collected at the beginning of the

flowering stage when they are in the healthiest state and contain the optimum

percentage of their active constituents. It's bitter to collect leaves when the weather

is not wet. Collection should be made in dry weather, since wet weather may cause

deterioration and discoloration during the drying process. The methods of collection

vary from one drug to another. In case of senna leaves, the whole plant is cut, and

the leaves are picked off after drying in the sun. Digitalis and coca leaves are

gathered directly from the plants.

193