Active principles in homoeopathic medicinal plants- phyto-constituents

Dr Vinod Solanki

Abstract
Plants form the major source for many of the drugs. The chemical substances obtained from plants are called ‘phyto-constituents. The chemical constituent which is responsible for the therapeutic effect is called the active principle. The medicinal value of a plant depends upon the nature of the chemical constituents present. Phytochemistry is the chemistry of plants, plant products and natural substances.

Keywords: Phytoconstituents, Phytochemistry,Therapeutic effect.

Introduction:
The quality of drug is determined by the amount of medicinal principles present in the drug. A plant or vegetable substance consists of cellulose and lignin which form the basic frame material of the roots, stem, leaves and other parts of the plant. The constituents in plants depend upon the species of the plant, its height at which these grow, the soil on which these thrive and various season of the year. There is a variation in composition of these constituents in the different part of the plant. The pharmacopoeias recommend the use of different part of the different plants accordingly.

Drug constituents are classified into various groups:

CARBOHYDRATES-

• Carbohydrates are polyhydroxyaldehydes and polyhydroxyketones.
• They contain carbon, hydrogen and oxygen. The ratio of hydrogen and oxygen is generally 2:1.
• The general chemical formula is C_n(H₂O)
• On heating they lose their water and form carbon.
• Carbohydrates are abundantly found in the storage region of plants.

Classification:

• Sugars
• Non- sugars.

SUGARS
Sugars are soluble carbohydrate food materials, generally sweet to taste.

E.g. Beetroot, Carrot

1) Monosaccharides: These are the simplest forms of carbohydrates.

• They may be of the following types:
• Pentoses: sugars having 5 carbon atoms. These are not common in plants.

E.g. Arbinose, Ribose.

Hexoses: sugar containing 6 carbon atoms.

E.g. Glucose present in all green plants.

Fructose present in fruits.

2) Oligosaccharides: This includes:

1. Disaccharides-

• Sucrose- Its concentration is very high in storage organs. It is mainly extracted from sugarcane stems and beetroots.
• Maltose- Commonly found in germinating seeds.

1. Trisaccharides-

• Raffinose: It occurs in very small quantities.

Non- sugars:

1. Polysaccharides: This includes:

• Inulin: occurs in cell sap of vacuoles of plants like Dahalia.
• Starch grains: More abundant in the storage organs, cereals, fruits and seeds.
• Glycogen: It present in blue green algae, moulds, fungi and bacteria.

2. Compound Carbohydrates: These are complex carbohydrate molecules.

Eg. Gums and mucilages, tannins, glycosides.

ORGANIC ACIDS, FATTY ACIDS AND LIPIDS
Fatty acids are generally long chains and can be saturated. The organic acids are soluble in water and are colourless. There are three major classes of lipids- triglycerides, phospholipids, glycolipids.

ALKALOIDS

• It is nitrogen containing heterocycle.
• Majority of the alkaloids are present in form of soluble salts, but some occur as free bases.
• Alkalies are extremely bitter, but some, like piperine are tasteless.
• Mostly odouless but nicotine have strong odour.
• Generally colourless, but berberine is yellow in colour.

GLYCOSIDES

Glycerides are non- reducing compounds. On hydrolysis they yield two components:

• An aglycone, also known as ganin.
• Reducing sugar.

TANNINS
They are found in several plants, especially in the leaves and bark. Tannins are non-nitrogenous and are soluble in water and alcohol. They have bitter taste. Eg. Rhustox, Hamamelis virginica, Millefolium.

OIL

Oils are chemical compounds of C, H and O but the ratio of hydrogen and oxygen is not 2:1. They remain in liquid state at ordinary temperature. Their solid state is termed as fats. Two main categories are:

• Volatile or essential oils
• Fixed or fatty oils.

Volatile oils

• They are volatile in nature.
• Fixed oils do not leave a permanent grease spot on paper.
• They can be distilled.
• They do not form soaps with alkalis.
• These do not become rancid.
• Generally inflammable.

Fixed oils

• Fixed oils are non-volatile and so leave a permanent grease spot on paper.
• Decompose under the influence of heat and become rancid.
• Almost bland, non- irritating substances.
• Form soap with alkalis.

PLANT EXUDATES

• Resin: These are natural or included exudates from plants. Resin may be obtained in either the solid or the semi-solid form in nature. They are insoluble in water but are can be readily dissolved in alcohol, ether and volatile oil.
• Oleo-resin: They can be obtained by incising the trunk of a tree. g. Copaiva officinalis,  Turpentine, Rhus tox.
• Gums: They are exudations from the stems or branches, or both, of plants. g. Asafoetida
• Gum-resin: These are natural mixtures of gums and resins. g. Asafoetida.
• Balsams: It is a semi-fluid fragrant, Aromatic acids are present in a high proportion in balsams. e.g. Peru balsam.

VITAMINS

Generally they are artificially synthesised. A few vitamins are synthesised by plants, like:

1. Alfalfa and spinach contain vitamin K.
2. Oranges contain vitamin C.

• Wheat germ oil contains vitamin.

Many plants do not synthesised vitamins, but they contain their precursors such as:

1. Carotene in carrots is a precursor of vitamin A.
2. Plant sterol, ergo sterol in yeast, moulds and fungi is the precursor of vitamin D.

REFERENCES:

• D Banerjee’s Augmented Textbook of Homoeopathic Pharmacy, 3^rd Edition.
• Partha MP, Mandal B. A Text Book of Homoeopathic Pharmacy.

Dr. Vinod Solanki
MD Scholar (Homoeopathic Pharmacy)
Guide- Dr. B.D. Dwivedi
Government Homoeopathic Medical College & Hospital, Bhopal(M.P.)
Email: solankivinod513@gmail.com.