the wild or cultivated plants are the major sources of crude drugs. The collection of a crude is more suitable when they contain maximum concentration of active constiuents. For this, suitable season, stage of development or age and the existing environmental conditons are taken into consideration while collecting the crude drugs. Some examples are given below.
- Roots and Rhizomes: Annual roots and rhizomes of medicinal plants are collected after their full growth. Biennial roots and rhizomes are collected in the spring of second year while perennials in the second or third year before they develop woody fibres. The collected roots and rhizomes are sliced transversely or longitudinally or in both directions to facilitate the drying.
- Leaves:
The leaves are collected befor or during the early part of flowering eg:: Senna, Digitalis, Vinca etc
- Stems and wood::
The stems are usually collected after the development of leaves. Pharmaceutically, the stem and woods are different. The wood consist almost entirely of the xylem tissues which are collected before the exhaustion of juice.
- Barks::
Barks are usually collected during spring or early summer when the cambium is active. Different methods have been used for the collection of barks:
.jpg)
Post a Comment