ON PHARMACOGNOSY AND PHYTOCHEMISTRY
Pharmacognosy is one of the essential pharmaceutical disciplines the purpose of which is to study natural medicinal and aromatic raw materials or drugs. The name pharmacognosy originates from Greek words: pharmakon – poison, drug or medication and gnosis – knowledge, cognition. On the basis of that, it can be established that pharmacognosy is science on drugs.
In pharmacognostic dictionary the word drug means dry part or dry organ of a certain medicinal or aromatic plant such as: flower, leaf, fruit, seed, crust, rhizome, tubers and others that have strong or mild pharmacologic effect and are used in pharmacy and medicine.
Pharmacognosy today primarily studies herbal raw materials, their morphology, anatomy, chemical composition and pharmacological effect. The use of raw materials is based on their composition, i.e. active ingredients that are bearers of medicinal properties of drugs such as: alkaloids, heterosides, saponosides, tannins, essential oils, etc. In certain countries, pharmacognosy is called material medica, and its old name means knowledge of drugs. The name pharmacognosy was first used by Sadler in 1845 and it has been accepted nowadays in almost all countries. The quality of medicinal and aromatic plants used as raw materials for obtaining drugs that can further be used in pharmacy should comply with standards required by domestic and foreign pharmacopeias. In order to obtain drugs that would be in compliance with prescribed pharmacopeia requirements, medicinal and aromatic plants need expert and conscious collecting and drying and responsible storage. Prior to collecting medicinal and aromatic plants, we should know which organ i.e. part of the plant should be collected and when, as various parts should not be collected at any given time. Leaves, petals, crust and root or other parts should not be collected from every plant but only from the ones prescribed by domestic and foreign pharmacopeias. Medicinal plants and their parts are collected when ripe, i.e. when they contain maximum active ingredients. Collected vegetative material should further on be properly dried and for that purpose it is necessary to know its anatomic and chemical composition. It is also important for plant organs to preserve chemical composition and natural appearance after the drying.
The chemistry of drugs called phytochemistry becomes more important in pharmacognosy and includes fast and practical methods of analyzing and extracting active substances from drugs or raw medicinal plants. The activity of large number of pharmacognosists and pharmacologists throughout the world is based on finding new active materials in drugs that would contribute to fighting against numerous diseases. Knowledge that medication obtained from plant is biological and that human organism can bear it better incites scientists to constant research in that field and results obviously follow.