INTRODUCTION TO PHARMACOGNOSY AND SCOPE OF PHARMACOGNOSY
1.
INTRODUCTION
The term comes from two Greek words: "pharmakon" meaning drug or medicine,
and "gnosis" meaning knowledge.
Pharmacognosy is "the study of the physical, chemical, biochemical and biological
properties of drugs, drug substances or potential drugs or drug substances of
natural origin as well as the search for new drugs from natural sources".
Pharmacognosy is the study of medicinal uses of various naturally occurring drugs
and its history, sources, distributions, method of cultivation, active constituents,
medicinal uses, identification test, preservation methods, substituents and
adulterants.
Plant preparations are said to be medicinal or herbal when they are used to promote
health beyond basic nutrition.
The study of drugs from plants includes the subjects of botany, chemistry and
pharmacology.
Botany includes the identification (taxonomy), genetics, and cultivation of plants.
Chemical characterization of includes the isolation, identification and
quantification of constituents in plant materials.
Pharmacology is the study of the biological effects that the chemicals in medicinal
plants have on cell cultures, animals and humans practical perspectives as follows
Quality control (identity, purity, consistency)
Efficacy (therapeutic indications, pharmacological investigations)
Safety (adverse reactions, drug interactions, contraindications, precautions)
2.
Crude Drugs: -
Crude drugs are the drugs, which are obtained from natural sources like
plant, Animals, minerals, marine, microorganisms and they are used as such
as they occur in nature without any processing except, drying & size
reduction.
Crude drugs is referred to the natural product that has not been in advanced
in value or improved in condition by any process or treatment beyond that
which is essential for its proper packaging and prevention from
deterioration.
History of Pharmacognosy:
Drug discovery from natural products have played and continue to play an
invaluable role as sources of drugs or lead compounds in the prophylaxis and
treatment of diseases.
Plants, especially those with pharmacological uses have been the primary sources
of medicines and have an advantage over other sources in drug discovery for
various reasons.
‘Pharmacognosy’—has been coined by the merger of two Greek words
Pharmakon means Drug and Gnosis means knowledge i.e., the knowledge of
drugs.
The nomenclature ‘Pharmacognosy’ was used first and foremost by C.A. Seydler,
In about 77 AD, Dioscorides, a Greek doctor, kept a record of about 600 kinds of
crude drugs in his compiled book De Materia Medica, a book that had played an
important role in pharmacology and botany.
3.
In 1815, C.A. Seydler, a German who used the word “pharmakognosie” in his
book named Analecta Pharmacognostica , was referred to as the father of
pharmacognosy.
Work of Galen: - (131 - 200)
Galen was Greek pharmacist; he worked on extraction of chemical constituent
from the plants. He developed various methods of extraction therefore the branch
of pharmacy which deals with extraction of chemical constituent from plants &
animals is called as Galenical Pharmacy.
Hippocrates (460 - 360. B.C.)
Before the birth of Jesus. He was Greek scientist; he worked on human anatomy &
Physiology Particularly on circulatory system & nervous system. He prepared
famous oath for physicians, which is still taken by the physicians. He is known as
father of medicine.
Indian History of Pharmacognosy: -
It is about 5500 years old, in the suktas of Rigveda & Atharwaveda medicinal
property of plant is given. There are several medicinal plants, which are given with
there use. The old Ayurveda Books, Charak samhita & Sushrutsamtita described
many medicinal plants.
4.
The Scope of Pharmacognosy:
Pharmacognosy gives a sound knowledge of the vegetable drugs under
botany and animal drugs under zoology.
It also includes plant taxonomy, plant breeding , plant pathology, plant
genetics and by this knowledge one can improve the cultivation methods for
both medicinal and aromatic plants.
Nowadays phytochemistry (plant chemistry) has undergone the significant
improvement.
This includes a variety of substances that are accumulated by plants and
synthesized by plants.
A vital contribution to the advancement of natural science:
This has done by the advanced technologies of cultivation, purification,
identification (characterization) of pharmaceuticals from nature.
Concepts of biochemistry and chemical engineering help in the
improvement of collection, processing and storage technologies of
pharmaceuticals.
It also gives knowledge of chemotaxonomy, biogenic pathways for the
formation of acute ingredients.
A vital link between pharmacology and medicinal chemistry:
5.
Newly detected plant drugs are converting into medicine as purified
phytochemicals.
Pharmacognosy is essential for the evolution of new medicines because
crude drugs are used for the preparation of galanicals or as a sources of
therapeutically active metabolites.
In short Pharmacognosy is an important link between pharmaceuticals and
basic science as well as ayurvedic and allopathic system of medicines.
Pharmacognosy is a science of active principles of crude drugs and which
can be help in dispensing, formulating, and manufacturing of dosage forms.
In other way the complete knowledge of Pharmacognosy will help in the
recent trend that is in industries,
As a research tools and in new drug delivery systems, and all the
departments of pharmaceuticals and one can improve the healthcare facilities
across the world.
6.
Newly detected plant drugs are converting into medicine as purified
phytochemicals.
Pharmacognosy is essential for the evolution of new medicines because
crude drugs are used for the preparation of galanicals or as a sources of
therapeutically active metabolites.
In short Pharmacognosy is an important link between pharmaceuticals and
basic science as well as ayurvedic and allopathic system of medicines.
Pharmacognosy is a science of active principles of crude drugs and which
can be help in dispensing, formulating, and manufacturing of dosage forms.
In other way the complete knowledge of Pharmacognosy will help in the
recent trend that is in industries,
As a research tools and in new drug delivery systems, and all the
departments of pharmaceuticals and one can improve the healthcare facilities
across the world.
Get link
Facebook
Twitter
Pinterest
Email
Other Apps
Comments
Popular posts from this blog
-
1. TABLETS General chapter 2. TABLETS • Tablets are solid dosage form each containing a unit dost of one or more medicament • Intended for oral administration • Some tablets are swallowed whole or after being chewed • some are dissolved or dispersed in water before administration • some are retained in the mouth where the active ingredient is liberated. 3. TABLETS • Because of their composition, method of manufacture or intended use, tablets present a variety of characteristics and consequently there are several categories of tablets. • Unless otherwise stated in the individual monograph, tablets are uncoated. 4. Different types of tablets • Uncoated tablets • Film Coated • Sugar Coated • Dispersible Tablets • Effervescent Tablets • Modified-release Tablets • Enteric-coated Tablets • Prolonged- release Tablets • Soluble Tablets • Tablets for Use in the Mouth
Tablet weight is mainly affected by factors such as tooling of the compression machine,head pressure,machine speed and flow properties of the powder.Inconsistent powder or granulate density and particle size distribution are common sources of weight variation during compression. Variation between tablet with respect to dose and weight must be reduced to a minimum.Uniformity of weight is an in process test parameter which ensures consistency of dosage units during compression. Test Procedure Weigh individually 20 units selected at random and calculate the average weight.Not more than two of the individual weights deviates from the average weight by more than the percentage given in the pharmacopea and none deviates by more than twice that percentage.IP/BP & USP limits for tablet weight variation is given below. IP/BP Limit USP 80 mg or less ± 10% 130mg
Comments
Post a Comment