Medicinal Plants (PPC101) Lecture Notes PDF

Medicinal Plants (PPC101) Reda F. A. Abdelhameed, PhD gu.edu.eg Lec2 The Pharmacopoeia: It is a governmental publication that contains A listing of all the official drugs with their description and requirements that make them sui...

Medicinal Plants (PPC101) Reda F. A. Abdelhameed, PhD gu.edu.eg Lec2 The Pharmacopoeia: It is a governmental publication that contains A listing of all the official drugs with their description and requirements that make them suitable for use by humans. A drug which is not listed in the pharmacopoeia is said to be unofficial. Examples: British Pharmacopoeia (B.P) United States Pharmacopoeia (U.S.P) Egyptian Pharmacopoeia (E.P.) The 1st E.P. (in English) in 1953 and (in Arabic) in 1961. Disadvantages of collection of wild plants for medicinal use: 1- Wild plants are distributed over unlimited areas 2- Difficulty in transportation (plants growing in deserts or forests) 3- Continuous collection lead to extinction of the plant 4- Can lead to adulteration due to ignorance of collectors 5- The collected amount to may be insufficient for the market demand.  Collection Proper time Proper stage of development  Proper time Time of year: The nature and the amount of active constituents varies throughout the year, e.g. Rhubarb contains no anthraquinones in winter, but instead it contains anthranols, which are converted to anthraquinone compounds in summer.  Proper time Time of Day: Amount of cardiac glycosides in Digitalis When collected When collected In the afternoon In the morning Proper stage of development Solanaceous leaves contain the maximum amount of alkaloids at the flowering stage. Santonica flowers are rich in the bitter principle santonin when they are non- expanded and show a decrease in the amount of this substance upon expansion. Collection of leaves Flowering stage the optimum percentage most healthy state of their active constituents Dry weather is a must  Collection of flowers Collection must be carried out in fine, dry weather in order to fix the colour of the product. Generally, they are gathered just at the time of pollination, before the formation of fruits. Cloves are collected in buds, while Chammomile flowers are collected just after full expansion.  Collection of barks This is usually carried out in the spring or in the early summer, when the cambium is active and can thus be stripped off easily from the trunk and branches. For the removal of bark, longitudinal incisions are made at intervals, round incisions are made and the barks are stripped off in long pieces.  Collection of fruits This is carried out near the ripening season, when they are fully mature but not completely ripened. They must be gathered in dry weather. colocynth  Collection of seeds The fruits are collected at the ripening stage and the mature seeds are separated from the pericarp. fenugreek Collection of unorganized drugs Unorganized drugs, e.g. resins, gums, latex, etc. should be collected in dry weather, excluding the vegetable debris during collection. They are obtained by making certain incisions in the plant and the resulting drug usually acquires the shape of the incision. acacia gum  Treatment of Drugs Before Drying: Some drugs, as underground organs, need cleaning and garbling prior to the drying process. The cleaning process includes the removal of soil particles from drugs by shaking, brushing, or washing under a stream of water. Some drugs, such as Ginger and Cinnammon, are decorticated to acquire a good appearance or to remove tissues containing undesirable substances. Garbling is the process of removal of foreign matter such as sand, dirt or other parts of the plants from the drug. This can be achieved either by hand or by a special machine. Metallic particles can be removed by passing the drug over a big magnet. The complete removal of foreign material is not practical, and for this reason the pharmacopoeias state certain limits of them.