pharmacognosy & phytochemistry

Pharmacognosy & Phytochemistry 1

Md. Asif Hasan NiloYPharmacy 3rd Semester (24 Batch)

EXTRACTION METHODS

Extraction:

Extraction, as the term is used pharmaceutically involves the separation medicinally

active portions of plants or animal tissues from the inactive or inert components by use

of selective solvents in standard extraction procedures. The products so obtained from

plants or relatively impure liquids, semi-solids or powders, intended only for oral or

external use.

Plant constituents are extracted from both dried and fresh plant materials. The dried

materials must be powdered before extraction. The fresh sample may be directly

extracted homogenized before extraction.

Extraction differs from solution in that the presence of insoluble matter is implied in the

former process.

The principle methods of extraction are:-

i. Maceration

ii. Percolation

iii. Digestion

iv. Infusion

v. Decoction.

i. Maceration: In this process the solid ingredients are placed in a stoppered container

with the whole of the solvent and allowed to stand for a period of at least three days

(until soluble matter is dissolved), with frequent agitation. The mixture is then strained,

the marc (the damp solid material) passed, and the combined liquids are clarified by

filtration by decontamination after standing.

ii. Percolation: This is the procedure most frequently used to extract the active

ingredients in the preparation of tinctures and fluid extracts. In the BPC general

percolator (a harrow cone shaped vessel open at both ends) is used. The solid ingredients

are moistened with an appropriate amount of specified men strum and allowed to stand



for approximately four hours in a well-closed container, after which the drug mass is

packed in the percolator. Sufficient men strum is added to saturate the mass and top of

the percolator is closed. When the liquid is about to drip from the neck (bottom) of the

percolator, the outlet is closed. Additional men strum is added to give a shallow layer

above the mass and the mixture is allowed to macerate in the closed percolator for 24

hours. The outlet of the percolator is then opened and the liquid contained there is in

allowed to drip slowly. Additional men strum being added as required, until the

percolate measures about three quarters of the required volume, and the mixed liquid

is clarified by filtration or by allowing it to stand and then decanting.

iii. Digestion: This is a form of maceration in which gentle heat is used during the process

of extraction. It is used when moderately elevated temperature is not objective able and

the solvent efficiency men strum increased thereby.

iv. Infusion: An infusion is a dilute solution of the readily soluble constituents of crude

drugs. Fresh infusions are prepared by macerating crude drugs for a short period of time

with cold or boiling water.

v. Decoction: This once popular process extracts water soluble and heat stable

constituents from crude drugs by boiling in water 15 minutes, cooling, staining, and

passing sufficient cold water through the drug to produce the required volume.

Extraction Process

The processes commonly used for the separation and purification of organic compound

are:-

i. Crystallization

ii. Sublimation

iii. Distillation

iv. Fractional Distillation

v. Distillation under reduced pressure



vi. Steam distillation

vii. Extraction with solvents

viii. Chromatography

i. Crystallization: This is the process, most commonly use for the purification of solid

organic compounds. This impure solid is dissolved in the minimum volume of a suitable

solvent. The soluble impurities pass into solution while the insoluble once are left behind.

The host solution is then filtered and allowed to cool undisturbed till crystallization is

complete. The crystals ar then separated from the mother liquor by filtration and dried.

The efficacy of the process of crystallization depends on the skill with which the

following steps are carried out:

a. Choice of solvents

b. Preparation of solution

c. Filtration of hot solution

d. Crystallization

e. Separation and drying of crystals.

a. Choice of solvents: For a judicious choice of the solvent, about 50 mg of the solid is

taken in a test tube and shaken with a few drops of the solvent. The solvent is

unsuitable if whole of the solid goes into solution at room temperature. If the solid

dissolves upon heating and throws out maximum crystals on cooling, the solvent is

suitable. This process is repeated with solvents such as: water, ether, ethyl alcohol,

acetone etc., till the most satisfactory one is sorted out.

b. Preparation of solution: A suitable quantity of the solid substance is taken in a conical

flask fitted with a reflux condenser. A small volume of the solvent selected in the step

(1) is also placed in the flask. The quantity of the solvent should be just enough to

dissolve the whole solid on boiling. The heating may be done on water both or wire

gauze according as the solvent is low boiling or high boiling.



c. Filtration of Hot solution: The hot solution obtained above is then filtered through a

fluted filter paper placed in an ordinary glass funnel if the quantity of the solution is

large, it takes longer and the crystals may form in the funnel during filtration. To

prevent this, a hot water funnel may be used.

d. Crystallization: The hot filtrated is then allowed to cool undisturbed in a beaker. The

pure solid substance separates as crystals. When a rich crop of crystals has been

obtained, crystallization is complete. Sometimes crystallization does not occur even

after cooling the filtrate for a sufficiently long time. In such a case the crystallization is

induced either by sketching the walls of the beaker with a glass rod or by adding a

few crystals of the pure compound to the solution.

e. Separation and drying of crystals: The crystals are separated from the mother liquor

by filtration. The filtration is generally effected under reduced pressure using a

Buchner (or Hirsch) funnel. When the whole of the mother liquor has been drained

into the filtration flask, the crystals are washed with small quantities of the pure cold

solvent to remove adhering impurities. The crystals are then dried by pressing

between parts of filter paper in a n oven, or in a vacuum desiccator.

ii. Sublimation: Some substances when heated pass. The vapor when cooled gives back

the solid substance. This process is known as sublimation. It is very helpful in separating

volatile from non-volatile solids. It is however of limited application as only a few

substances like naphthalene, camphor, and benzoic acid can be purified by this process.



The impure substance is placed in a large beaker. The beaker is covered with a watch

glass. Heat is applied gently to the beaker, and the resulting vapors condense as crystals

on the bottom surface of the watch glass can be removed after some time and the

crystals collected.

#### Organic substances such as benzoic acid, naphthalene etc., which have high vapor

pressure at temperature below their melting points, can be sublimed relatively quickly.

These can be conveniently purified by the method described above.

Substances which have very small vapor pressure or tend to decompose upon heating are

purified by sublimation under reduced pressure.

The glass apparatus used for sublimation under reduced pressure is shown in the figure.

The chief features of this apparatus are a large heating and a large cooling substance with

a small distance in between. This is necessary because the amount of the substance in the

vapor phase is much too small in case of a substance with low vapor pressure.

iii. Distillation: The operation of distillation is employed for the purification of liquids

from non-volatile impurities.



The impure is built in a flask and the vapors so formed are collected and condensed to

give back the pure liquid in another vessel. The non-volatile impurities are left behind in

the flask.

The apparatus consists of a distillation-flask flitted with a thermometer in its neck

and a condenser at the side-tube. The liquid to be purified is placed in the distillation

flask and the thermometer so adjusted that its bulb stands just below the opening of the

side-tube. This ensures the correct reading of the thermometer of the vapor passing over

to the condenser. A suitable vessel is attached to the lower end of the condenser to

receive the condensed liquid. On heating the distillation flask, the thermometer first

records a rise in temperature which soon becomes constant. At this point which is the

boiling temperature of the pure liquid, most of the liquid passes over. Towards the end

of the operation the temperature rises once again on account of the superheating of the

vapor. The distillation is stopped at this stage and the receiver disconnected.

In case of liquids having boiling points lower than 110, the water condenser is replacedby air condenser. To patient bumping, it is customary to put a few pieces of unglazed

porcelain in the distillation flask.

While distillation a very volatile and inflammable liquid such as ether, the

distillation flask is heated or a water-bath and not on a wire-gauze. In case of high

boiling liquids, the flask is heated directly with a naked flame.



iv. Fractional Distillation: A mixture of two or more volatile liquids can be separated by

fractional distillation. When their boiling point differs by more than 40, the operationcan be carried with the help of ordinary distillation apparatus. The more volatile liquid

passes over first and collected in a receiver.

When the temperature begins to rise for the second time, the first receiver is

disconnected. A new receiver is attached as soon as the temperature becomes constant

once again. Thus the distillate is collected in fraction and the process is termed fractional

distillation.

When the liquids present in the mixture have their boiling point close to each

other, the separation is best effected by fitting the distillation flask with a fractionating

column which is tern is connected to the condenser. On heating, the vapor of the more

volatile liquid A, along with a little of the vapor of the less volatile liquid B, rise up and

come in contact with the large cooling surface of the fractionating column. The vapors of

B condense first wing down the column meets the fresh hot ascending vapor. It snatcher

more of B from the vapor mixture and gives up any dissolved vapor of A. This process is

repeated at every bulb of the fractionating column so that the vapor escaping at its top

consists almost exclusively of A and the condensed liquid following back into the

distillation flask in rich in B. if necessary the process can be repeated with the distillate

and the liquid left in the distillation flask.

The used of the fractionating column has found a remarkable application in

modern industry especially in the distillation of petroleum, coal-tar and crude alcohol.



v. Distillation under reduced pressure: In case of organic liquids which decompose before

their boiling point is reached, the distillation is carried under reduced pressure when the

liquid boils at a lower temperature.

1. Claisen Flask, having two necks. It is filled with long down jet dipping in the liquid to

be distilled. During the distillation, a steam of bubbles rises through the capillary of this

jet and presents bumping which is so pronounced here than in ordinary distillation.

2. Condenser, connected with the claisen flask on the one hand and a filtration flask,

serving as a receiver, on the other.

3. Manometer, The receiver flask is connected to an exhaust pump through (a) a mercury

manometer which tells the pressure under which the distillation is being carried, and (b)

a trap, to eliminate any condensed liquid.

The pressure in the apparatus is reduced with the help of a water pump. Whenever a

lower pressure is desired, the water pump is replaced by a mercury pump.

An important application of this process is the recovery of glycerol from spent-lye

in soap industry. Glycerol decomposes at its boiling point (298) by can be distilledunchanged at 12 mm pressure when it boiled at 180. Another application of vacuumdistillation is the concentration of sugar juice under reduced pressure.



vi. Steam Distillation: Many substances that are insoluble in water and volatile in steam

can be purified by distillation in a current of steam. The non-volatile impurities are left

behind in the distillation flask.

The impure mixture together with some water is placed in a round-bottom flask

which is then connected to a steam-generation on one side and a water condenser on the

ether. The flask is adjusted standing position so that no droplets of the mixture splash

into the condenser on brisk boiling and bubbling of steam. The mixture in the flask is

heated and then a current of stem passed into it. Heating of the flask is controlled so as

to avoid unnecessary condensation of steam in it. Steam ricks up the volatile substance

from the mixture and passes into the condenser. The distilled collected in the receiver

consists of a mixture of water and the organic substance. The distillation is stopped when

the droplets or the solid particles of the organic substance curse to appear in the

condenser.

The distillation is then treated to recover the organic substance by a suitable

method. In case it is a solid, the substance may be separated by simple filtration and if

it is a liquid, it can be removed by means of a separating fennel. The aqueous layer in

both cases may be extracted with a solvent.

Steam distillation is employed in industry for the recovery of various essential oils

from plants and flowers. It is also used in the manufacture of aniline and temperature oil.



PRINCIPLE OF STEAM DISTILLATION

A liquid boils when its vapor pressure is equal to the atmospheric pressure. In steam

distillation a mixture of water and an organic liquid is heated. The mixture boils when

the combined vapor pressure of water (P1) and that of the organic liquid (P2) is equal to

the atmospheric pressure (P). i.e.:

P = P1 + P2

THE CHROMATOGRAPHIC STUDY OF CRUDE DRUGS

INTRODUCTION TO CHROMATOGRAPHY

The study of chromatography has become prominent as a means of separating and

analyzing organic and inorganic materials. Large amounts as well as micro-quantities may

be employed and the analyses may be conducted either by qualitatively and

quantitatively. Chromatographic methods often prove more effective than other means

of separation and identification of solutions of drug principles. Such techniques are

finding wide applications in research in pharmacognosy involving the determination of

identity and purity of drugs and derivatives of natural origin as well as in pharmaceutical

research and manufacturing processes.

CHROMATOGRAPHY

May be defined as a method of analysis in which the flow of the solvent or gas promotes

the separation of substances by diffential migration from a narrow initial zone in a

porous sportive medium. The two major subdivisions arc solution chromatography and

gas chromatography.



IMPORTANCE OF CHROMATOGRAPHY

i. It is one of the most important analytical tools.

ii. It serves as a means for the resolution of the separated substances.

iii. It permits the separation and partial description of unsuspected and unknown

substances.

iv. It is an indispensible laboratory method in all sciences dealing with chemical

substances and their reactions.

v. It is among the most selective and most widely applicable separator- techniques yet

devised.

ORGINAL CONCEPT OF CHROMATOGRAPH

In its classical form, as first described by a Russian botanist, M. Ts wett in 1906,

chromatography is a method of separating substances by filtering their solutions through

a column of a finely powdered adsorbent, filled into a glass tube, then washing

(developing) the column with a solvent. This results in the separation of the various

components of the mixture due to their selective adsorption. The separated substances

from distinct zones in the column. They are then separated by cutting the column or are

washed down fractionally. Tis original concept of chromatography was suitable for only

colored substances, like pigments. Over the years, the chromatographic techniques have

undergone tremendous modification and improvement making separating not only

colored substances, but also closely related colorless substances of all description.

CLASSIFICATION AND NOMENCLATURE OF CHROMATOGRAPHIC PROCESS

Chromatography is a separation technique where separation is affected by a number of

ways and by the application of various may be summarized as follows:-

a. Separation by adsorption.

b. Separation by Partition

c. Separation by ion exchange

d. Separation by electric charge

e. Separation by particle size difference.



In all these methods in separation two different phases are involved:-

1. Stationary Phase: Which may be a solid or liquid series as the carrier or holder of

the mixture to be separated, is called the stationary phase.

2. Mobile Phase: Which may be a liquid or a gas, moves through the stationary

phase pushing or carrying the compounds of the mixture over it at different

speeds depending on the affinity of the individual components for the two phases.

This moving phase is called the mobile phase.

On the basis of separation principles chromatographic process may be broadly divided

into the following major groups:-

(i) Adsorption chromatography: In this technique, a pure solid in powdered from is used

as the stationary phase and a liquid or gas as the mobile phase.

(ii) Partition chromatography: In this case, a liquid coated on an inert solid support

serves as the stationary phase and a liquid or a gas as this mobile phase.

(iii) In-exchange chromatography: In this method, separation in carried out on some solid

ion-exchangers by the use of an aqueous solution as the mobile phase.

(iv) Elect chromatography or Electrophoresis: In electrophoresis, electric charge is used to

effects separation of the components of a mixture. This can be used either as partition

or as adsorption chromatography. In this technique, an electrolyte serves as the mobile

phase or the medium.

(v) Gel filtration: in this method of separation, porous solids with a defined narrow

distribution of pores are used as the stationary phase and a liquid as the mobile phase.

This is also called a molecular sieve process or exclusion chromatography as the

separation of the different components of a mixture depends on the size of their

molecules.

Most of these chromatographic processes may be carried out in a number of different

ways. They can be carried out by using columns of adsorbents or on this layer of

adsorbents spread on glass slabs, or on paper, or by the use of gases. Depending on

the specific technique employed chromatographic methods are also variously named--



i. Coiumn Chromatography (CC): when the adsorption or petition chromatographic

separations are carried out on a column of adsorbents packed in a glass or metallic tube.

ii. Thin-layer Chromatography (TLC): When the adsorption or partition chromatography

is performed on a thin layer of adsorbents spread on glass plates, metal or aluminum

sheets.

iii. Paper Chromatography (PC): when the partition chromatographic process is carried

on a filter paper.

iv. Gas Chromatography: when gas is used as the mobile phase to carry put the

adsorption (gas solid chromatography or GSC) or partition chromatography (gas liquid

chromatography or GLC).

v. High performance liquid (HPLC): It is a liquid column chromatographic technique,

which is highly mechanized, sophisticated, efficient and speedy in operation. It employs

relatively narrow columns and operates at ambient temperatures of up to about 200atm. This can be used both as an adsorption and partition chromatographic technique.

PAPER CHOMATOGRAPHY (P.C)

Paper chromatography is a simple method with which a large number of analyses can be

conducted simultaneously, paper chromatography is more popular. Two techniques may

be employed:- The descending and the ascending, depending upon whether the mobile

phase moves downward or upward on the chromatograph paper. The ratio of the

distance travelled on the paper sheets by the test substance to the distance by the front of

the mobile phase, from the point of application of the test substance, is termed the Rr

value.

The resulting spots or pattern of distribution on the paper is called the chromatogram.

PREPARATION OF PAPER CHOMATOGRAPHY

The solution of the mixture to be separated is applied as a spot near one end of a

prepared filter paper strip. The paper is then supported in a n air tight tank which has an

atmosphere saturated with the mobile phase and water vapors. Development of the



chromatogram in this case can be achieved by an ascending technique or by a descending

technique.

In the ascending technique the mobile phase is either poured in the tank directly or taken

in a trough placed at its bottom. The end of the paper holding the spot of the

component mixture is dipped into the mobile phase up to just below the spot.

In this descending technique a trough containing the mobile phase is positioned near the

top of the tank and the paper is hanged from the trough by the end of the strip which

holds the spot, but the spot remaining outside the trough. The mobile phase runs

downward and along the paper and the chromatogram is developed. Naturally the

speed of development is higher in this case.

As the mobile phase runs up or down, as the case may be, the components also move

along the paper at varying rates, depending on the differences in their partition

coefficients between the stationary phase (water in the filter paper) and the mobile

phase. When the solvent front travels to the desired distance the paper is with down and

rapidly dried.

THIN-LAYER CHROMATOGRAPHY (TLC): Analysis of small amounts of the substance to

be situated.

Advantages

Ease of operation

Wide application to a great number of different samples.

High sensitivity

Higher speed of separation and

Relatively low cost.

THE TECHNIQUE

Basically TLC is an adsorption is an adsorption chromatographic technique in which the

adsorbent, acting as the stationary phase, is coated or a glass slab or plastic sheet or

aluminum acid in the form of a uniform thin layer. In order to prepare a stable layer of



the absorbent on the plate a suitable binding agent or binder is used along with the

adsorbent.

PREPARATION OF THESE PLATES

In preparing the plates the adsorbent, with or without a binder, is made into slurry with

a proportionate quantity of distilled water. The slurry is then quickly poured into a

spreader. This consists of a rectangular box open at the top and a hollow cylinder which

can be rotated through 180 the slurry empties and passes out through an adjustable slit

at the bottom of the spreader to give a layer of desired thickness. The plates to be coated

are faced edge to edge on a stable support. The spreader is held over the first plate and

when the slurry starts coming out on rotating the cylinder, the spreader is drawn across

the plates.

The coated plates are left far while on the support for setting and air drying of the

adsorbent. They are then carried on same suitable racks to an oven where they are

activated by healing at a temperature of 110 to 135 for half an hour to one hour. After

activation the plants are stored in a deflector. The usual thickness for a thin layer of

adsorbents used for analytical work is 250 micron.

PREPARATION, DEVELOPMENT OF THIN-LAYER CHROMATOGRAMS

Samples of mixtures are taken into solution usually in an organic solvent. They are

applied on the thin layer as spots at once end of the plate in a straight line about 3cm

above the edge and 1.5cm away from the margins. Capillary tubes are used for applying

the spots. Care must be taken not to disturb or break the layer of the adsorbent in the

process. When the spots are dry, the plates are placed inside a chromatographic tank

containing the motile phase taking care not to submerge the applied spots under the

mobile phase. In that case the compounds will be washed away by the mobile phase and

be lost. The mobile phase should be poured into the tank at least 30 minutes before

dipping the spotted plate, that is, the inner atmosphere of the tank must be allowed to

saturate with the vaporous of the mobile phase before starting the exercise. This is better



achieved by liming the inner side of the tank with a filter paper or cloth soaked with the

mobile phase. After dipping the plate the tank should be closed firmly and left

undisturbed until the operation is complete. The solvent or mobile phase runs along the

thin layer in an ascending manner due to capillary action. As the mobile phase moves up

it carries the components of the mixture along with it. They move at different speeds

depending on their affinities for the mobile and stationary phases and are thus resolved

into separate spots. When the solvent reaches or reasonable height the operation is

stopped, the solvent front marked and the plate is dried using suitable techniques.

Column Chromatography

The adsorption or partition chromatographic separations are carried out on a column of

adsorbents placed in a glass or metallic tube.

It has been defined as uniform percolation of a fluid through a column more or less finely

divided substance which selectively retards certain components of the fluid.

In the column method, many adsorbents have been used such as----- sucrose, talc, calcium

or sodium carbonate, activated alumina, silicic acid and fullers earth.

Solvents/(eluents): Petroleum ether, carbon-tetrachtoride, carbondissulfide, ether,

acetone, alcohol, water and mixtures of acids and bases in water, alcohol and pyridine.

The absorbent is packed uniformly into a suitable glass or quartz tube, and the solution

of the drug or substance in a small amount of eluent is passed through the column.

According to their adsorption coefficients, the various constituents in the drug or

substance are removed from the solution and are adsorbed in transverse bands at varying

distances from the top of the column. Each component progresses downward at a

characteristic rate.

Lhpon drying, the resulting column consists of a series of bands separated components

and is known as the chromatogram, this is removed from the tube as a single column and

then divided into the separated bonds for individual analysis.



A modification of the column method known as a flowing chromatogram depends upon

a larger quantity of the solution to be eluted being introduced into the tube.

The liquid is allowed to flow continuously through the column until the separated

substance appears in the discharged solution (eluate). It is then identified either as the

solution or as the evaporated material.

Another modification is known as partition chromatography; in this two immiscible

liquids are used. One representing an Immobile phase, the other a mobile phase.

LIST OF COLUMN CHROMATOGRAPHY

The Chromatographic methods have been extensively used in the resolution of mixtures

and isolation of all types of organic compounds.

It has been successfully utilized in the separation of a number of inorganic substances.

Repeated column chromatography is a popular method of initial purification of

many natural substances.

PHYTOCHEMISTRY OF PLANT DRUGS

Many plants possess therapeutic and pharmaceutical properties. The medicinal and

pharmaceutical properties of these plants are due to the type of the chemical substances

they produce and store.

The usual term used to refer to these various chemical substances present in plants is

constituents. The constituents which possess pharmacological properties are called

active constituents.

Phytochemistry is concerned with the chemical study of these plant constituents.



The Chremistry of Drugs:- The living organism may be considered a biosynthetic

laboratory, not only for chemical compounds (carbohydrates, proteins, fats) that are

utilized as food by man and animals, but also for a multitude of compounds (glycosides,

alkaloids, volatile oils) that exert a physiologic effects. These chemical compounds give

plant and animal drugs their therapeutic properties.

Active constituents are differentiated from inert constituents which also occur in plant

and animal drugs. In plant drugs cellulose, lignin, suberin and cutin are usually regarded

as inert matter; in addition, albumin, colouring matters and other substances may have

no definite pharmacological activity and also are considered inert constituents.

In animal drugs keratin, chitin, muscle fire and connective tissues are regarded as inert

often the presence of inert substances may modify or prevent the absorbability or

potency of the active constituents. To eliminate the undesirable effects of inert matter in

the crude drugs or its preparations, active principles are extracted, crystallized and

purified for substances.

Active constituents may be divided into two classes:-

i. Pharmaceutically active and

ii. Pharmacologically active.Pharmaceutically active:-

Constituents may cause precipitation or other chemical changes in a medicinal

preparation.

For instance, neither cinchona bark nor its extracts could be used in formulating

preparations containing iron salts because the cinch tannic acid would combine with

these salts and cause precipitation.

Cinch tannic acid, then is a pharmaceutically active constituent.

The use of Quinine Hydrochloride obviates this incompatibility since it is a purified

crystalline compound, without the slightest trace of cinchotannic acid.

In contrast, the rheotannic acid present in Rhubarb serves as an astringent to prevent

the griping action usually associated with anthraquinone drugs of that type.

In this case, rheotannic acid is one of the pharmacologically active constituents.



Depending on the particular activity of the constituent and on the other constituents

or ingredients with which it is associated, certain principles may be placed in one or the

other category.

Pharmacologically active constituents:-

These are those to which the therapeutic activity of the drug is attributed.

They may be either single chemical substances or mixtures of principles, the

separation of which is neither practical nor advantageous.

The single chemicals are exemplified by sugars, starches, plant acids, enzymes,

glycosides, alkaloids, proteins, hormones, and vitamins.

The mixtures include fixed oils, fats, waxes, volatile oils, resins, oleoresins, gum-resins

and balsams.

Active constituents and the drugs containing them are:

Carbohydrates and Related Compounds:-

Compounds composed of carbon, hydrogen, and oxygen as polyhydroxy aldehyde or

ketonene alcohols, sucrose, lactose, corn starch, traganath, agar, acacia, pectin.

Carbohydrates are classified according to their constitution.

Those having 6 carbon atoms (C6H12O6) are called Hexoses or Monosaccharaides.

Those having 12 carbon atoms (C12H22O11) are called Disaccharides.

Those having 18 carbon atoms (C18H32O16) are called Tri saccharides etc.

Such simple carbohydrates, because of their solubility and sweet test are commonly

referred as sugars.

The more complex, high molecular weight polysaccharides can usually be

hydrolyzed to a component hexose and are therefore called hexoses.

Starch which yields glucose is known as a glucosan. Insulin yielding Fructose is

known as a fructose.



Monosaccharaides:-

Chemically a simple sugar is defined as a substance belonging to the carbohydrate group

which is a ketonic or aldehydic substitution 9product of a polyhydroxy alcohol). The

simplest of these would be a diose HO-CH2-CHO (hydroxyl acetaldehyde) which does

not occur free in nature. An aldehydic and a ketonic triose do exist (glyceraldehyde and

dihydroxy acetone) usually in the form of phosphate esterts.

Moreever, certain organisms are capable of oxidizing glycerin to dihydroxyacetone.

The tetroses also have not been found in the Free State.

Pentoses, however occur commonly in nature usually as products of hydrolysis of

hemicelluloses.

Disaccharides: -

Of the disaccharides, sucrose in the only member that occurs abundantly in the Free State

in plants, although maltose has been reported as occasionally present in the cell sap.

Sucrose occurs in fruit juices, sugarcane, sugar beet, the sap of certain maples and

in many other plants.

Upon hydrolysis it yields inert sugar which consists of equimolecular quantities of

glucose and fructose. Sucrose is a non-reducing sugar.



Hexoses: -

Are by far the most important monosaccharides found in plants.

There are 16 possible aldohexoses and 8 keto hexoses which, if we consider both the

and forms, permit 48 isomers. Of these, only 2 are found occurring in the Free State

bin plants. They are D-fructose & D-glucose (dextrose). Both are found in sweet fruits,

honey and invert sugar.

When starch is hydrolyzed it yields glucose, Inulin yields fructose upon hydrolysis.

Glucose is an aldohexose, that is a polyhydroxy alcohol having an aldehyde group while

fructose having a ketone ketone group in a ketohexose.

These groups explain the reducing properties of the monosaccharides and account for

commonly applied term Reducing Sugars.



Glycosides are compounds that yield, upon hydrolysis, one or more sugars among the

products of hydrolysis. The most frequently occurring sugar is Dglucose, cynarose

and other sugars are found as components of glycosides.

Chemically, the glycosides are acetyls in which the hydroxyl of sugar is considered with a

hydroxyl group of the non-sugar component, and the secondary hydroxyl group is

considered within the sugar molecule itself to form an oxide ring. More simply, they may

be considered as ethers. The non-sugar component is known as the glycine; the sugar

component is called the glycine.

Both alpha & beta glycosides are possible drugs containing glycosides, which liberate

physiologically active constituent only upon hydrolysis and do not constituent only upon

hydrolysis and do not contain it in the free state, are sometimes known as Reactionary

Drugs.

Using the chemical

nature of the aglycone

group as a basis of systematization, the classification of the glycoside containing drugs is: -

1) Cardioactive group

2) Anthraquinone Group

3) Saponin group

4) Cyanophore Group

5) Thiocyanate Group

6) Flavanol Group

7) Alcohol Group

8) Aldehyde Group

9) Lactone Group

10) Phenol Group

11) Others



1) Cardioactive Glycosides:

The members of this group are characterized by their highly specific action on cardiac

muscle, increasing tone, excitability and contractility steroidal glycosides, which occur in

Digitalis, strophanthus, squill etc.

2) Anthraquinone Glycosides:

A number of glycosides related to anthracene are present in such drugs as Cascara

Sagrada, Frangula, Aloe, Rhubarb, Indian Rhubarb, Senna, Chrysarbin and Cochineal.

With the exception of Chrysarobin and Cochineal, these drugs are employed as

cathartics.

The glycosides, on hydrolysis, yield aglycones which are di, tri, or tetrahydroxy

anthraquinones or modifications of these compounds.

Example: Frangulin Frangula emodin + RhamnoseFairbarin has shown that, without the sugar groups, free anthraquinones exhibit little

therapeutic activity. The sugar moiety is essential because it serves to transport the glycon

to the site of action in the large intestine.

Without sugar groups, the aglycone, would largly disappear during metabolism. The

compounds give a positive Borntrager reaction and are responsible for the laxative action

of these drugs.

Biosynthesis of Anthraquinone Glycosides: - Feedings of labeled acetate to penicillium

islandicum a species which produces several anthraquinone derivatives, have revealed

that the distribution of radioactivity in these compounds is consistent with formation via

a head-to-tail condensation of acetate units.



A poly--ketomethylene acid intermediate is probably first produced and then gives six

to the various oxigenarated aromatic compounds following intramolecular

condensations.

3) Saponin Glycosides:

This group of glycosides is widely distributed in the higher plants.

Saponins are characterized by forming colloidal solutions in water which foam upon

shaking\. They have a bitter, acrid taste and drugs containing them are usually

sternutatory and other wise irritating to the mucous membrane.

They destroy red blood corpuscles by hemolysis and they are toxic espically to cold

blooded animals, many having been used as fish poisions.

Upon hydrolysis they yield an aglycone known as a sapogenin. The sapogenins from

readily crystallizable compounds upon crystallization by which means they may be

purified and studied. The most poisonous saponins are often called sapotoxins.

Biosynthesis of Saponin Glycosides: - Saponin glycosides are divided into two different

types based upon the chemical structure of their aglycones (sapogenins).

Neutral salonins are derivatives of steroids with spisoketal side chains; the acid saponins

possess triterperiod structures.

A brance occurs after the formation of the triterpenoid hydrocarbon saequence, which

leads to steroids in one direction and to cyclic triterpenoids in the other.



Biosynthesis of Sapogenins: - Saponin Glycosides: - Sarsaparilla, Glycyrrhiza, Ginseng.

4) cyanophore Glycosides:

Several glycosides yielding hydrocyanic acid as one of the products of hydrolysis are

commonly found in sosaceous plants. They are sometimes designated as cyanogenetic

glycosides.

The common cyanophore glycosides are derivatives of mandelonitrile

(benzaldehyde cyanohydrin). The group is represented by amygdalin which is found in

large quantities in better amounts in the kernels of apricots, cherries, peaches, plums and

many other seeds of Rosaceae and also by prunasin which occurs in prunus padus, both

of which yield D-mandeclomitsile as the aglycone and sambunigrin from sambucus migra

liberates L-man-delonitrile as its aglycone.

When amygdalin is hydrolyzed it forms two molecules of glycose. While these are

usually written as linked in apparent di-saccharide form it is particularly noteworthy that

it has never been possible to break off a disaccharide sugar from the molecule by any

known means of hydrolysis.



Amygdalin is thereforer a true glucoside rather than a maltoside. The hydrolysis of

amygdalin takes place in three steps, which are briefly as follows: -

1) Most hydrolyzing agents break the molecule first so as to liberate one molecule of

glucose and one of mandelonitile glucose.

2) In the second step the next molecule of glucose is liberated with the formation of

benzaldehyde-cyanohydrin known as mandelonitrile.

3) The mandelonitril;e then breaks down with the formation of benzaldehyde and

hydrocyanic acid.

5) Thiocyanate Glycosides:

The seeds of several cruciferous plants contain glycosides, the aglycones of which are

thiocyanats. Principal among these glycosides are sinigrin from black nuestard, sinalbin

from white musters and gluconapin from rape seed.

When hydrolyzed by the enzyme myrosin, they yield the mustard oils.

Biosynthesis of Thiocyanate Glycosides: - Aglycones of thiocyanate glycosides may consist

of either aliphatic or aromatic derivative. Isotope feeding studies have shown that at least

one example of the former type is biosynthesized via the acetate pathway and one of the

iatter type via the shilamic acid route.



For example, carboxy-labeled acetate was incorporated in the allylmoiety of sinigrin in

Brassica juncea.

Studies with phenylanaline labeled in both the --carbons and the mitrogen atom of the

alahive moiety have shown that the side chain of the acid is decarboxylated and then

incorporated as unit into glucotropaeolin in tropaeolum majus.

6) Flavonol Glycosides:

The glycosides rutin, hesteridin and quercitrin are related to the flavones.

Chemically, rutin 3, 3, 4, 5, 7 pentahyhoxyflavae-3-rutinoside. Thus, it is associated

with the pigment glycosides.

Many, if not all, of the red, yellow, violet and blue pigments in plants either exist as

glycosides or are derived from them. The pigment glycosides are usually classified into

the three following types: -

a) The, Anthraqui, suchas alizarin from madder root

b) The flavoncs or xanthones most of the yellow pigments found in plants are

flavones, such as chrysin.

c) The anthrocyanins and Anthoxan thirs these include most of the red, blue and

violet pigments found in plants.



Biosynthesis of Flavonol Glycosides: - The flavonol glycosides as well as other related

compounds generally termed flavonoids, related compounds generally termed

flavonoids, are examples of products derived from both of the major path ways leading

to the synthesis of aromatic compounds in biological systems.

One six-carbon fragment of these C6-C3-C6 compounds derives from acetate metabolism

and the rehaining nine-carbon portion from the shikimic acid (phenylpropanoid)

pathway. The following scheme indicates how the C8-C3 portion.

Probably in the oxidation state of a cinnamic acid, combines with these molecules of

acetate to form a C15 chalcone intermediate and then a flavanone.

Introduction or removal of hydroxyl groups from rings A & B results in the production of

a large number of quantities.

Flavanols are probably first formed by introduction of the hydroxyl group in position 3

and then dehydrogenation of positions 2 & 3 results in the production of flavonols.

7) Alcohol Glycosides:

Salicin is an alcoholic glycoside which hydrolyzes into saligenin (salicyl alcohol)

Another glycoside populin (benzylsalicin) is associated with solution in barks of the

salcaceac.

Coneferin: - A glycoside found in the cambial layer of many pines, yields coniferyl

alcohol on hydrolysis.



Coniferyl alcohol when oxidized with K2Cr2O7 yields vanillin.

Biosynthesis of Alcohol, aldehyde, lactone, and phenol Glycosides: - The aromatic nuclei

of some compounds (alcohol, aldehyde, lactone and phenol glycosides) derived from C6 -

C3 precursors formed via the shikimic acid pathway.

8) Aldehyde Glycosides:

Salinigrin occurring in Salix discolor consists of glucose contained with m-

hydroxybenzaldehydes thus representing a glycoside having an aldehyde glycine.

Salinigsin is an isomer of helium (o-hydroxybenzaldehyde plus glucose) and may also be



obtained by the mild oxidation of salicin. Amygdalin which yields Benzaldehyde on

hydrolysis may also be classified in this group.

Vanilla is an official drug having an aldehydic aglycone as its chief constituent.

9) Lactone Glycosides:

Coumarin is widely distributed in plants, glycosides containing coumarin as such are

raised several of its hydroxyl derivatives however are known. None are of particular

medicinal importance. The -pyrone structure of coumarin may be illustrated as follows.

10) Phenol Glycosides:

The aglycone groups of the many of the naturally occurring glycosides are phenolic

character. Thus, arbutin found in Uva Ursi, Chimaphila and other other ericaceous drugs,

yields hydroquinone and glucose upon hydrolysis:

Hesperidin which occurs in various citrus fruits and is included with the Flavone group,

may be classified as a phenol glycoside.

11) Other Glycosides:

Gentian or Gentian root:- is the dried rhizome and roots of Gentiana lutca Linne.

Family: Gentianaceae.

Genntian yields not less than 30% of water soluble extractive and contains not more

15% of moisture. The plant is a large perennial herb indigenous to central and southern

Europe and AsiaMinor.

Quassia, Pierotoxin, Khellin, Saffron.



VOLATILE OILS

VOLATILE OILS:-

Volatile oils are the odorous principles found in various plant parts. Because they

evaporate when exposed to the air at ordinary temperatures, they are called volatile oils,

ethereal oils or essential oils.

The last term is applied since volatile oils represent the essences or the active

constituents of the plants.

Volatile oils are colorless as a rule,

Particularly when they are freshly obtained, but on long standing they may oxidize and

resinify, thus darkening in color.

To prevent this, they should be stored in a cool, dry place in tightly stoppered,

preferably in full amber glass containers.

In the plant parts they occur in glandular hairs, modified parenchgmatous cells, oil

tubes called vital and in some special oil ducts.

Chemical constituents of volatile oils may be divided on the basis of their biosynthetic

origin into two broad classes: -

1) Terpene derivatives formed via the acetate mevalonic acid pathway.

2) Aromatic compounds formed via the shikimic acid phenylpropanoid route.

METHODS OF OBTAINING VOLATILE OILS:-

Volatile oils are usually obtained by distillation of the plant parts containing the oil, the

method depending on the condition of the plant material.

Three types of distillation are used: -

i. Water Distillation.

ii. Water and Steam Distillation and

iii. Direct steam Distillation.



WATER DISTILLATION

It is applied to plant material that is dried and not subject to injury by boiling.

Turpentine oil is obtained in this manner. The crude turpentine oleoresin is introduced

into the distillation chamber and subjected to heat until all volatile matter is condensed

in the condensing chamber.

Turpentine oil, is not affected by this amount of heat.

WATER AND STEAM DISTILLATION

It is employed for substances that may be injured by boiling. In the case of dried material

(cinnamon, clove), the drug is ground and then covered with a layer of water, and steam

is passed through the macerated steam is passed through the macerated mixture. Since

the oil might be impaired by direct boiling, the steam is generated elsewhere and is piped

into the container holding the drug. The oily layer of the condensed distillate is separated

from the aqueous layer, and the oil may be marketed with or without further processing.

DIRECT STEAM DISTILLATION

Applicable to fresh plant drugs (peppermint, bspearmint), the crop is cut and taken

directly to the distilling chamber. Steam is forced through the fresh carrying the oil

droplets to the condensing chamber.

During steam distillation certain components of a volatile oil tend to hydrolyze where

as other constituents are decomposed by the high temperatures.

Ideal distillation methods utilizing steam should provide for the diffusion rate of steam

and water through plant, membranes to be as possible and should thus keep the

hydrolysis and decomposition at a minimum.



MEDICAL AND COMMERCIAL USES: -

Many crude drugs are used medicinally because of their volatile oil content; in numerous

cases, the volatile oils separated from the drugs are used as drugs in themselves.

Various crude drugs are powdered and are employed as spices and condiments.

The most common use for the volatile oil drugs as well as for the separated oils is

flavoring purposes. They all possess a carminative action but a few possess additional

therapeutic properties. In addition to their pharmaceutical use, the volatile oils are

employed widely as flavors for foods and confections and in the spice, perfume and

cosmetic trades. Many volatile oils possess antiseptic properties.

CHEMISTRY OF VOLATILE OILS:-

Most volatile oils consists largely of trepnes which are isomeric hydrocarbons would

naturally account for the presence of alcohols, aldehydes, ketones, phenols, phenolic

ethers; esters and oxides. Since these oxygenated compounds are responsible for the

characteristic odors, testes and therapeutic properties of the volatile oils, if follows that a

chemical classification of the oils should be based on the principal chemical constituents.

The following are the divisions in which volatile oils-contains drugs are placed:

1) Hydrocarbons: Cubeb, Pepper, Turpentine oil.

2) Alcohols: Peppermint, Cardamom, Coriander, Rose oil, Orange flavor oil, Pine oil

3) Aldehydes: Cinnamon, Lemon peel, Citronella oil, Bitter almond oil.

4) Ketones: Camphor, Spearmint, Caraway, Buchu.

5) Phenols: Thyme, Clove, Marcia oil, Creosote, Juniper Tar.

6) Phenolic Ethers: Amine oil, Fennel oil; Myristica, Sassafras.

7) Oxides: Chenopodiam oil; Eucalyptus oil.

8) Esters: Levered oil; Rosemary oil, Bergamot oil; Mustard oil; Gaultheria oil.s

9) Others: Angelica herb.



ALKALOIDS

Alkaloids are organic nitrogenous compounds. All do occur in plants, but some are found

in animals, and practically all have been represented in the laboratory by chemical

synthesis.

Alkaloids may occur in various parts of the plant in seeds (Nux vomica areca) , in

fruits (black papper, conium), in leaves (belladonna leaf, hyoscyamus), in rhizomes and

roots (ipecae, hydrastis), and in barks (cinnhona, pon-cgranate)

The names of the alkaloids are obtained in various ways: -

1. From the genetic name of the plant yielding them.

2. From the common name of the drug yielding them.

3. From the specific name of the plant yielding them.

4. From the physiological activity.

5. Occasionally from the discoverer.

Alkaloids usually contain one nitrogen atom although some like ergotamine may contain

up to five. The nitrogen may exist as a primary amine (RNH3), as a secondary amine

(R2NH) or a tertiary amine (R3N).

Such compounds are basic, but the degree of basicity varies greatly depending

upon the structure of the molecule and the presence and location of other functional

groups.

For the most parts the alkaloids are insoluble or sparingly soluble in water but reacts with

acids to form salts which are usually freely soluble.

The free alkaloids are usually soluble in ether or chloroform or other relatively

non-polar, immiscible solvents in which, however, the alkaloidal salts are insoluble.

Most of the alkaloidal salts are crystalline solids, although a few are amorphous, and an

additional few which lack oxygen in their molecules are liquids.

Alkaloids are usually classified according to the nature of the basic chemical structures

from which they derive.



Important ring structures present in alkaloidal and other drugs. Various schemes for the

classification of alkaloids have been suggested. The following plan is based on the ring

structure or nucleus of the chief alkaloid in the plant drug

1) Pyridine piperidine combined group.

2) Tropane Group.

3) Quinoline Group

4) Isoquinoline Group

5) Indole Group

6) Imidazole Group

7) Steroidal Group

8) Lupinane Group

9) Alkaloidal amine Group

10) Purine Group.



(1) Pyridine Piperidine Alkaloids: Upon reduction the tertiary base pyridine is converted

into the secondary base piperdine is converted into the secondary base piperdine. These

two nuclei from the basis of this group.

This group is sometimes divided into 4 sub-groups.

(i) Derivatives of piperdine including piperine from black pepper and methysticin

from kava.

(ii) Derivatives of ptopylpiperidine including coniine from conium.

(iii) Derivatives of micotinic acid including arecoline from areca.

(iv) Derivatives of both pyridine and pyrolidine including micotine from tobacco.

The important alkaloidal drugs drugs and their alkaloids which are classified in this group

are: Areca, Areccoline Hydrobromide, Lobelia, Lobelin, Pomegranate, pelletierine

Tanate, Comium, Coniine, Piperine, Nicotine, Trigonelline.



(2) Tropane Alkaloids: Tropane is a dicyclic compound formed by the condensation of

pyrroledine and paperidine, as follows: -

Pyrrolidine occurs free in small quantities in tobacco and opium and is tetrahydropyrrole.

To this group belong such alkaloids arehygrine from Erythroxylon coca and stachydrine

from stachus luberifera.

Belladonna, Hyoscyamus, Stramonium, Cocaine.



(3) Quinoline Alkaloids: Alkaloids congaing quinoline as the principal nucleus include

those obtained from Cinchona:- quinine, quinidine, cinchomine and cinchomidine; and

viridicatin from penicillium viridicatum.

Cinchona.

(4) Isoquinoline Alkaloids: The isoquinoline structure occurs in a considerable number of

alkaloids in widely separated plant families.

Although the more important opium alkaloids exhibit a phenanthrene nucleus, the

majority of its alkaloids have the isoquinoline ring structure.

Phenanthrene alkaloids are derived biosynthetically from benzylisoquinoline

intermediates. For these reasons Opsium is included in thus group.

The structure of paparerine is typical of the benzylisoquinolines: -



The important drugs and their alkaloids of these group are: - Ipecae, Emetine, Hyclrastis,

Hydrostine, Sanguinaria, Curare, Tubocurarine, Berberis, berberine, opium and its

alkaloids.

(5) Indole Alkaloids: A number of important alkaloids possess an indole ring as part of

their structure.

Strychnine and brucine (dimethoxystrychnine) from Nux Vomica and physostigmine

from physostigma belong to this group.

Strychmine and brucine contain in addition a quinoline mucleus so it may be

classified in the quinoline group also

Raiwolfia Serpentina, Catharathes, Nux vomica, pheysostigmine, Ergot.

(6) Imidazole Alkaloids: The imidazole ring is the principal nucleus in pilocarpine from

pilocarpus.

Pilocarpine is a mono acidic tertiary base containing a lactone group as well as the

imidazole nucleus.



(7) Steroidal Alkaloids: The steroidal alkaloids are characterized by the

ctclopentenophenanthrene nucleus.

They are apparently either formed from cholesterol, or they and cholesterol have a

common peecursor.

The important drugs and their alkaloids of this group are veratrum vimide,

veratrum album, rotoveratxine, aconite, aconitine and larruper.

(8) Lupinane Alkaloids: Sparteine, a liquid alkaloid, is the only medical representative of

this group. It is derived from Scoparius. Acrystalline alkaloid, lupinine, is obtained.

(9) Alkaloidal Amines: The alkaloids in this group do not contain heterocyclic nitrogen

atoms.

Many are simple derivatives of phenylethylamine and as such are derived from the

common amino acids phenylalamine or tyrosine, Ephedmine, Colchicine.



(10) Purine Bases: The purines are derivatives of a heterocyclic nucleus consisting of the

six membered pyrimidine ring fused to the five membered imidazole ring.

Purine itself does not occur in nature. But numerous derivatives are biologically

significant.

The pharmaceutically important bases of this group are all methylated derivatives of

2,6 dioxypurine (xanthine).

Coffein in 1, 3, 7 trimethylxanthine, theophylline in 1,3- dimethylxanthine.

Coffeine containing drugs, Theophylline, Theobromine.



FIBERS AND SURGICAL DRESSINGS

Fibers and the surgical dressings made from them are of immense value in medical and

pharmaceutical practices.

Dressings are compulsorily needed for proper management and subsequent healing of

wounds caused by injuries, burns, microbial infections and surgical operations. They are

used to provide ample protection to the exposed tissues against microbial infections and

other natural hazards. The surgical dressings not only aid the healing process but also

help stop further tissue damage.

The sources of wound management largely depends on the type and quality of the

dressings used, to be able to choose the right kind of the surgical dressings one must be

aware of the types of available dressings, their qualities and usefulnesss.

The quantity of a surgical dressing depends on the type of the fiber used to prepare the

dressing.

FIBERSFibers are used for dressing purposes both in their normal forms and in woven or fabric

forms. Fibers that are useful in wound management and healing include both natural and

artificial or synthetic fibers. Natural fibers may be of plant or animal origin.

Plant fibers include epidermal trachoma, such as cotton, and other fibrous tissues of

plants, such as cotton, and other fibrous tissues of plants, such as phloem fibers (e.g.,

jute) and pericyclic fibers (e.g., Flax and Hemp).

Fibers of animal origin are derived from some animal products such as wool and silk.

Artificial fibers, prepared by processing or regenerating some tissue elements of plant

animals such as wool cellulose (e.g., Rayons, Cellulose, Wadding and Alginate fibers) are

also frequently used in wound management and surgical dressings. Some synthetically



prepared fibers, such as nylon and terylene, have also been used for dressing wounds and

burns.

The various groups of fibers used for surgical dressings may be conveniently summarized

in the following way: -

Some Important Fibers of Surgical dressings:

COTTONSynonyms: Raw cotton, Cotton wool, Absorbent cotton.

Biological Source: Cotton consists of the epidermal trichomes of the seeds of Gossypium

herbaceum Linn.

Family: malvaccae.

Preparation of Raw cotton and Absorbent cotton Wool: Bolls of cotton are collected

from the ripe and dehisced fruits of gossypium.



The trichomes are separated from the seeds by a ginning process using a machine

called a gin in which the trichomes are drawn through a narrow space. The masses of

these separated trichomes constitute raw cotton. Raw cotton thus prepared contains

impuriries, chiefly coloiring matter. And about 0.6% of wax and oil, which form a thin

film around the filters and render them the non-absorbent. Raw cotton is then variously

treated, combed and spinned to convert it to yarn or thread, which are woven to make

fabrics and cloths.

Absorbent cotton on wool: Is prepared from various cotton wastes obtained during the

processing of raw cotton for waking gains; The wastes are loosened and then boiled for

10 15 hours under a pressure of about 30lbs in a dilute solution of caustic soda and ash.

This treatment removes the fatty cuticle and renders the trichomes absorbent. The boiled

material is then washed thoroughly with water, bleached with dilute sodium

hypochlorite solution and treated with very dilute hydrochloric acid.

The balanced mass of fibers is then dried, loosened, scotched and carded by using

appropriate machines.

The resultant product is a thin continuous film of absorbent cotton wool. Several such

films are superimposed on one another and rolled.

Constituents: Raw contains about 90% of cellulose and small amounts of wax, fat,

remains of protoplasm, ash. Absorbent cotton is almost pure cellulose.

Uses: Cotton is used as the chief material for many surgical dre3ssings. It is also used as a

filtering medium and an insulating material.

JUTESynonyms: Gunny.

Preparation of Jute Fiber: Jute plants are normally straight and unbranched. They are cut

from the base when the plants are in flower, tied into small bundles, stacked and soaked

in stagnant water for about three weeks for retting. The stacks are covered with straw or

water hyacinths to keep them wet and to protect from direct sunlight. When the stem



bark is well-macerated by the retting process, the stands of the phloem fibers are

separated manually from the wood and washed free from the surrounding softer tissues

and other dirts thoroughly in clean water. The fibers are then dried in direct sunlight and

made into small bundles. Jute fiber is exported in bales made by hydraulic pressure.

Constituents: Jute fibers are composed of 53% cellulose and 22% hemicellulose and

contain 11% of lignin, 1% of fats and waxes and 1% of ash.

Uses: In pharmacy jute is used for the manufacture of medicated tows, for padding

splints, as a filtering or straining medium and for soaking fluids. Other industrial uses of

jute include the manufacture of ropes, Gunny bags, carpet backings and yarns for some

fabrics.

FLASKPreparation of Flax: The plants are uprooted by hand just about the fruits, tied in sheaves

and left to dry in the field. The dried plants then undergo a ripping process to remove

the capsules. After which the stems are tied in bundles and subjected to a retting

process.

When retting is complete, the stalks are dried in the sun, broken into pieces in a mill

and pieces of the xylem tissues removed by the teeth of a sketcher. The residual bark

from the stem is then mechanically combed to make the fibers parallel.

Constituents: Flax is made up to pecto cellulose.

Uses: Flax is used as a filtering medium for some preparations. It is rarely used in the

manufacture of lint.

WOOLSynonyms: Animal wool, Sheeps wool.

Preparation of Wool: The hairs are cut from the sheep at appropriate intervals and dirt

removed by beating on a sieve screen. The dirt-free hairs are then thoroughly cleaned by

washing with soap and sodium carbonate.



The wool is taken bleached with sulphurdioxide or hydrogen peroxide, thoroughly

washed and dried by hot air on wire netting.

Constituents: wool fibers are composed almost entirely of the protein keratin which

contains C, H, O, N, S.

Uses: Wool is used in the manufacture of dressings like flannel, domette and crepe

bandages.

SILKPreparation of Silk: The cocoons, a covering of filaments produced by the larvae of the

silk warm around themselves before passing to their pupal stage. They are then taken or

steamed to kill the pupal.

The cocoons are then placed in hot water to soften and removed partly the natural

gum of the silk filaments. The ends of the filaments from two to six cocoons are then

caught up. A number of these are twisted together to form a single thread of raw silk.

This raw silk is made up into hanks for processing into fibers.

Constituents: The mass of the silk fiber is made up of the protein fibroin, coated

externally by another protein serein or silk gum, which cements the fiber together. The

proteins of silk do not contain sulphur.

Uses: The pharmaceutical use of silk includes manufacture of ligatures, oiled silk and

some sieves.

CELLULOSE WADDINGSynonyms: Wool cellulose, Chemical wool pulp.

Source: Cellulose wadding is prepared from bleached sulphite wood pulp obtained from

the wood of various conifers.

Constituents: Cellulose wadding consists almost entirely of pure cellulose.

Uses: Cellulose wadding is used as the chief material for many surgical dressings.



RAYONSynonyms: Regenerated cellulose, artificial cellulose

Constituents: It consists of 0.3% of sulphur and yields about 0.2-0.3% of ash.

Uses: Lint, gauze, net and other surgical dressings are made from viscose rayon.

ALGINATESynonyms: Calcium Alginate fibers.

Uses: Calcium alginate fibers are used to prepare gauzes for absorbable haemostatic

dressings and bacteriological swabs.

NYLONSources: Nylon is a synthetic fiber, chemically synthetized polymerization from long

chain adipic acid and hexamethylenediamine. The polycondesation product in molter

condition is pumped through a spinning machine and the resultant filaments are cold-

drawn to increase their length.

Description: Nylon fibers are smooth, solid and cylindrical.

SURGICAL DRESSINGS (2nd)

Surgical dressings are a general term applied to various fibrous materials used for scientific

and hygienic management of wounds and for providing sufficient protection to the

exposed tissues. They include both loose masses of fibers and fabrics, gauzes, lints,

plasters etc. made from them. For convenience of description, surgical dressings may be

divided into various smaller groups according to their state of occurrence, composition,

method of preparation and uses.



The groups of various types of surgical dressings may be summarized as follows: -

GAUZESGauzes are usually absorbent dressings principally made from cotton fabrics.

They can be either medicated or unmediated. Medicated gauzes and also other

medicated dressings are prepared by immersing the fabric in a solution of the

medicament and drying off the solvent. Gauzes used for surgical dressings may be

conveniently grouped as follows: -

UNMEDICATED GAUZES

1) Absorbent Gauze: This gauze consists of a plain-wove cotton fabric, 36 inches wide,

with not less than 19 threads per inch in the warm and 15 in the weft ( ). One

square yard of the gauze weighs not less than 11.5g.



2) Absorbent Ribbon Gauze: This is finer than not less than 30 threads/inch in the warm

and 25 in the weft. A 2 in by 6 yard piece of the gauze weighs not less than 12.3g.

3) Absorbent Gauze Tissue: This is a sleeve-like which encloses a thick layer of absorbent

cotton wool. The fabric used in this gauze has 12 threads/inch of weft. One round of this

gauze must have a superficial area of not less than 1800 square inch.

4) Cellulose Tissue: This is also tubular absorbent gauze like the gauze tissue. But it

encloses a thick layer of cellulose wadding instead of absorbent cotton wool.

Medicated GAUZES

1) Boric Acid Gauze: It contains 3 to 7% of Boric acid, is tinted pink with a suitable lie.

2) Euflavine Gauze: This gauze is medicated with 0.1% of Euflavine.

3) Double Cyanide Gauze: This contains a mixture of Mercury cyanide (0.5 to 1.5%) and

zinc cyanide (1.5 to 3.0%) and is tinted purple with a suitable dye.

4) Iodoform Gauze: This medicated gauze contains 4 to 6% of Iodoform.

5) Trinitrophenol Gauze: It contains 1.5 to 2.5% of trinitrophenol.

6) Capsium: This is tubular absorbent gauze which encloses capsicum.

BANDAGESBandages are continuous length of fabrics and contain no joins. Their edges are evenly

cut, parallel with the warm threads. They are reasonably free from loose threads.

Bandages are chiefly made from plain or treated cotton cloths, but some of them are also

made from wool. In addition to these, there are some bandages which are made from

fabrics containing a mixture of both cotton and wool. Bandages may therefore be

grouped into four categories according to the type of fabrics they are made from as

follows: -



BANDAGES

Plain cotton Cloth Bandages

1. Open-wove Bandage2. Bleached Calico Bandage

3. Unbleached Bandage4. Muslin Bandage

Treated Cotton Cloth Bandage

1. Battiste2. Jaconet3. Oiled Cambric4. Zinc paste Bandage

Wool-containing Bandage

1. Flannel Bandage

2. Domette Bandag

3. Crepe Bandage

Silk Bandage Oiled Silked Bandage

Plain Cotton Cloth Bandages

1) Open-wove Bandage: This is a white bandage which contains not less than 43

threads/inch in the warp and 27 in the weft. A 2 4 yard open-wove bandage weighs notless than 12.96gm.

2) Bleached Calico Bandage: This is a very closely woven white bandage containing 67

threads/inch in the warp and 58 inch is the weft. A 2 4 yard bleached calico bandageweighs not less than 13.6gm.

3) Unbleached calico Bandage: This bandage contains 65 threads/inch in the warp and 60

in the weft. A piece of A 2 4 yard size of this bandage weighs not less than 16.2gm.4)Muslin Bandage: This is a bleached bandage of fine threats band may be regarded as

very closely woven absorbent gauze. It contains 48 threads/inch in the warp and 30 in

the weft. One aquare ft of this bandage weighs not less than 3.25gm.



Treated Cotton Cloth Bandages

The bandages are made of cotton fabrics which are variously treated to render them

waterproof on one or both sides. They may be medicated or unmedicated.

1) Battiste: It is a bleached fabric, rendered impervious to water by proofing its both

sides with rubber.

2) Jaconet: This is also a bleached fabric like Battiste, but it is waterproofed only on one

side with rubber.

3) Oiled Cambric: This is yellow-colored cambric rendered waterproof by treatment with

drying oils or oil modified synthetic resins.

4) Zinc Paste Bandage: It is a bleached open-wove bandage, impregnated with a zinc

oxide paste.

Wool Containing Bandages

These bandages are made from fabrics which consist either entirely of wool or of a

mixture of wool and cotton threads.

1) Flannel Bandage: This consists of wollen fabric, the threads of which have been raised

to form a nap. It contains 26 threads/inch in the warm and 28 in the weft. A 2 6 ydflannel bandage weighs not less than 58.3gm.

2) Domette Bandage: It is made up of a mixed fabric, which contains cotton threads in

the warp (not less than 40/inch) and wool thread in the weft (not less than 22/inch), 2 6yd of this bandage weighs not less than 28.5gm.

3) Crepe Cambric: This bandage also consists of a mixed fabric, which contains both

wool and cotton threads in the warm and only cotton threads in the weft. However, it

contains not less than 33.3% of wool, which is responsible for its crepe nature.

When fully extended, the bandage must measure not less than twice the length of

its unstretched condition. It must return to not more than 2 3 of the fully extendedlength after being held fully stretched for one minute.



Silk Bandage

Silk fabrics are used to prepare some special type of surgical dressings.

Oiled Silk Bandage:

This bandage consists of a pure silk fabric having 120 threads/inch in the warp and 85 in

the weft. The bandage is rendered completely waterproof by treating the fabric with a

suitable drying oil or an oil-modified synthetic resin. It may be colored green with a

suitable dye.

LINTSLints are medicated or unmedicated absorbent surgical dressings. They are made of plain-

wove absorbent cotton fabrics. The threads in the warm of the lint-fabrics are raised to

form a nap. They contain not less than 39 threads/inch in the warp and 24 in the weft.

230 to 250 square inch superficial area of the lints should weigh about 28.35gm.

The following medicated lints are available: -

1) Boric Acid Lint: This contains 3 to 7% of boric acid, and is tinted with a suitable dye.

2) Euflavine Lint: This type of link contains about 0.1% of euflavine.

PLASTERSPlasters are a kind of adhesive bandage made from bleached cotton fabrics. An adhesive

compound is spread on one side of the bandage to make it stick to the skin. Plasters may

be either medicated or unmediated. Some common plasters include: -

1) Rubber Adhesive Plaster: This is a bleached cotton fabric of prescribed standard,

prepared with an adhesive compound spread on one side and waterproofed with rubber

on the other side.

2) Zinc Oxide Plaster: This is similar to rubber adhesive plaster, but medicated with 20 to

30% of zinc oxide added to the adhesive compound.



3) Elastic Adhesive Plaster: This consists of medicated elastic cotton fabrics spread with an

adhesive compound which contains 20 to 30% of zinc oxide.

4) Plaster of Paris Bandage: This is also a medicated cotton fabric plaster, rendered

adherent to the skin by a suitable adhesive. This bandage is impregnated with at least

80% of exsiccated calcium sulphate.

SERGICAL DRESSINGSThis group of surgical dressings includes some standardized compound dressings

described in the British Pharmaceutical Codex and other official publications. These

dressings are prepared ready for use and consists of a pad of medicated cotton wool,

gauze or lint stitched to an open-wove bandage at certain distance from one end. The

longer end of the bandage is rolled and placed inside the pad and the other end is

wound round the rolled pad. The complete dressing is wrapped in impermeable paper

and sterilized.

However, in case of standard elastic adhesive dressings, the pad is fixed to a base of

elastic adhesive cotton fabric, and no bandage is required. This type of standard dressings

is not sterilized.

The standard dressings of B.P.C are numbered 1 to 15 and variously named as follows: -

Standard Dressing No. 1

This dressing is also known as Double Cyanide Dressing and consists of separate pieces of

double cyanide gauze, Absorbent cotton wool and opens-wove bandage, all wrapped

together and sterilized.

Standard Dressing No. 2

This standard dressing, which is also known as Fomentation Dressing, consists of separate

pieces of Boric Acid lint, Absorbent Cotton wool and an open-wove bandage, all

wrapped together and sterilized.



Standard Dressing No. 3, 4. 5 & 6

They are collectively known as Elastic Adhesive wound dressings and differ from each

other only in size. All of them consists of a pad fixed centrally to a flesh-colored elastic

cotton fabric with an adhesive margin all round. The pad is made up of a strip of lint

enclosed in one-ply Muslin bandage; both medicated with about 5% of boric acid and

tinted pink with a dye.

Standard Dressing No. 7, 8 & 9

These dressings are also called medicated wound dressings. They consists of a Boric acid

lint, superimposed on Absorbent cotton wool and attached to an open-wove bandage.

They differ from ezch other in size.


They are popularly known as burn dressings. These dressings are similar to the medicated

wound dressings, but their pads are made of Euflavine lint instead of Boric acid lint. They

also differ from each other in size only.


These dressings are commonly referred to as Plain Wound Dressings and are prepared in

three different sizes; small (13), medium (14) and large (15). They consists of a pad of

Absorbent cotton wool, enclosed in Absorbent gauze and attached to an open-wove

bandage.



VITAMINS & VITAMIN CONTAINING DRUGS

VITAMINS:

Vitamins are organic compounds necessary to the normal growth and maintenance of life

in animals, including man.

They do not furnish energy and are not utilized as building units for the structure of

the organism, but they are essential for the regulation of the metabolic processes.

They act in the capacity of enzymes during the metabolism of energy yielding food

constituents.

When the natural supply of vitamin is lacking, a number of deficiency diseases occur.

Thus, vitamins are therapeutic agents of value in the prophylaxis and treatment of these

diseases.

Vitamins are derived from a variety of sources, both plant and animal. They are

usually isolated, concentrated and purified for use as drugs; many of them are now

synthetized.

VITAMIN AVitamin A, the anti-infective, antixerophthalmic vitamin and its naturally occurring

isomer, now vitamin A are both found in Cod liver oil and other fish liver oils.

The following biological functions of vitamin A may be listed;

1) It is specific in the prevention and cure of xerophthalmia and nyctalopia.

2) It prevents hyperkeratosis of the skin which may occur in several cases of vitamin

A deficiency.

3) It is useful in overcoming retardation of growth and development when this is

due to vitamin A deficiency.

4) It is of value for increasing resistance of the body to infection only when there has

been an inadequate injection of vitamin A.



VITAMIN B COMPLEXThe vitamin B complex includes a number of dietary essentials which are found in

significant quantities in liver and yeast.

Thiamine/Vitamin B1: Occurs as small, crystalline powder, decomposing at 248; ina dry form, it is relatively stable to heat and light, in aqueous solution the pH is about 3.1

and such solution may be sterilized by heating for 20 minutes at 120 or for 1 hour at100, without applicable loss of potency.Daily requirement: adults 1.2 to 2mg, infants 0.4 to 0.8mg, children 1 to 1.8mg.

Sources: Enriched cereals, whole grain crenels, milk, legumes, and meats. Special sources

include yeast, liver concentrates and synthetic thiamine.

Riboflavin/Vitamin B2: was first identified in milk, and because of its yellow color is

known as lactochrome and later as lactoflavin.

It occurs naturally in the free form or in various chemical complexes with protein,

phosphoric acid, adenine or nucleic acid. Riboflavin is slightly soluble in water and in

alcohol; and is insoluble in lipoidal solvents.

Daily requirement: adults 1.6 to 3mg, infants 0.6 to 1.8mg, children 1.8 to 2mg. The

therapeutic dose is 3 to 5mg.

Sources: Milk, egg yolk, liver, meats, green leafy vegetables and bread.

NIACIN/NICOTINIC ACID and

NIACINAMIDE/NICOTINAMIDEThe names niacin and niacinamide have been recommended by the food and nutrition

board of the National recharge council because these names do not have the phonetic

similarity to nicotine as do the other names.



They have the following structural formulas: -

Daily requirement: adults 12 to 20mg, infants 6 to 12mg, children 4mg. The maximum

therapeutic dose is 500mg/day.

Sources: Meats, liver, eggs, milk and nuts. In addition, it has been found that four cups of

strong coffee provides an adequate daily intake.

PANTOTHENIC ACIDIt is the designation for the factor in the vitamin B complex necessary for the proper

growth of animals. It is also known as the chick antidermatitis factor.

It is dextrorotatory and is usually marketed as the calcium salt, dextro calcium

pantothenate.

Daily requirement: The therapeutic dose is 1 to 10mg.

Sources: Liver, kidney, yeast, milk cereals, legumes and nuts.

PYRIDOXINE / VITAMIN B6Pyridoxine consists of a group in which pyridoxine is one of three members.



Pyridoxine hydrochloride melts at 204 to 208 is soluble in water, alcohol andacetone and slightly soluble in other organic solvents.

It is stable toward heat, concentrated acid and alkali, but is destroyed by light.

Daily requirement: Therapeutic dose is 25 to 200mg orally or parentally.

Sources: Meats, seafood, cereals, legumes and yeast.

CYAROCOBALAMIN / VITAMIN B12It is a crystalline compound isolated originally from liver extract.

It occurs as dark red crystals or as a crystalline or amorphous powder; when

Anhydrous it is very hydroscopic and may absorb 12% of water if exposed to the air.

Uses and dose: Cyanocobalamin is a hematop

pharmacognosy & phytochemistry

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