Branch: Al-Arish
Research Project Title
Physical preparation of herbal product
Research Project Code: PHG E 11
Research Group No.: (B)
Submitted by:
201817458
201816308
201816603
201816145
201815994
‫عليه سليمان محمد‬
‫امنيه محمد عبد الحميد‬
‫اماني السيسي السيسي‬
‫خلود عبد الهادي المحمدي‬
‫ساره سعيد حسن‬
Supervised by:
Dr .MAYADA EL. AYOUTY.
Abstract:
In crude plant evaluation,
physical methods are often
used to determine the
solubility, specific gravity,
optical rotation, viscosity,
refractive index, melting point,
water content, degree of fiber
elasticity, and other physical
characteristics of
the herb material.
INTRODUCTION
In the last few decades there has been an exponential growth in the field of
herbal medicine. It is getting popularized in developing as well as in developed
countries owing to its natural origin and lesser side effects.
In olden times, Vaidyas used to treat patients on individual basis, and prepare
drug according to the
requirement of the patient.
But the scenario has changed
now; medicines are being
manufactured on the large
scale in pharmaceutical units,
where manufacturers come
across many problems such
as availability of good quality
raw material, authentication
of raw material, availability
of standards, proper
standardization methodology
of single drugs and formulation & quality control parameters.
Quality control for the efficacy and safety of herbal products is of paramount
importance. Quality can be defined as the status of a drug that is determined by
identity, purity, content, and other chemical, physical, or biological properties, or
by the manufacturing processes. Quality control is a term that refers to
processes involved in maintaining the quality and validity of a manufactured
product.
In general, all medicines, whether they are of synthetic or of plant origin, should
fulfill the basic requirements of being efficacious and safe, Standardization of
herbal drug refers to “confirmation of its identity and determination of its quality,
purity and detection of nature of adulterant by various parameters like
morphological, microscopical, physical, chemical and biological observations.”
Physical parameters:
color, odor, appearance, clarity, viscosity, moisture content, pH, disintegration
time, friability, hardness, flowability, flocculation, sedimentation, settling
rate and ash values.
physical method of evaluation of drugs?
Physical contents such as elasticity in fibers, viscosity of drugs containing gums,
swelling factor for mucilage containing materials, congealing point of volatile and
fixed oils, melting and boiling points and water contents are some important
parameters used in the evaluation of drugs.
Physical Methods of Drug Evaluation
(a) Foreign matter:
I.
II.
III.
IV.
Parts of medicinal plant material or material other than those named with
the limits specified for the plant material concerned.
Any organism, part or product of an organism, other than that named in
the specification and description of the plant material concerned.
Mineral admixtures not adhering to the medicinal plant materials such as
soil, stones, sand, and dust.
Molds, insect, or other animal contamination Method.
Weigh accurately 100 gm to 500 gm of original sample and spread it out in a
thin layer. Inspect the sample with the unaided eye or with the use of a 6X lens
and separate the foreign organic matter manually as completely as possible.
Weigh and determine the percentage of foreign organic matter from the
weight of the drug taken. Use the maximum quantity of sample for
coarse or bulky drugs.
(b) Optical Rotation.
The optical rotation is indicated by α, being the angle through which the plane of
polarization is rotated when polarized light passes through a layer of liquid. The
rotation can be clockwise or towards the right (Dextrorotation) or anti-clockwise
or towards the left (levorotation) and designated, respectively as +ve and
negative. The rotation is studied usually at the wavelength of sodium D line at a
temperature of 19.5 to 20.50 C, on a layer I dm thick.
(c) Melting point:
Dry finely powdered material under reduced pressure transfer to a dry capillary
tube by tapping to a height of about 4-6 mm. Heat slowly a suitable liquid as
mentioned above stirring constantly. Place the bulb of the thermometer
immersed in the liquid so that the graduation shows very clearly. Attach the tube
containing the material to this thermometer and watch closely maintaining eyes
at proper level with the thermometer. Observe the temperature at which
liquefaction of the sample takes place.
(d) Ash values:
Ash values are helpful in determining the quality and purity of crude drugs,
especially in powder form. The objective of ashing vegetable drugs is to remove
all traces of organic matter, which may otherwise interfere in an analytical
determination. On incineration, crude drugs normally leave an ash usually
consisting of carbonates, phosphates and silicates of sodium, potassium,
calcium, and magnesium.
Determination of Ash values:
I.
Total ash:
Take about 2 or 3 g, accurately weighed, of the ground drug in a tarred
platinum or silica dish previously ignited and weighed. Scatter the ground drug
in a fine even layer on the bottom of the dish. Incarnated by gradually
increasing the heat- not exceeding dull red heat-until free from carbon, cool
and weight.
If carbon free ash cannot be obtained in this way, exhaust the charred mass
with hot water, collect the residue on an ash less filter paper, increase the
residue and filter paper, add the filtrate, evaporate to dryness and ignite at
low temperature.
Calculate the percentage of ash with reference to the air-dried drug. Example:
Curcuma longa not more than 90%; Glycyrrhiza globra not more than 10.0%
II.
Acid- insoluble ash:
Boil the total ash with for five minutes with 25 ml of dilute hydrochloric acid,
collect the insoluble matter in a Gooch crucible or on an ash less filter paper,
wash with hot water, ignite, and weigh. Calculate the percentage of acidinsoluble ash with reference to the air dried drug. Example Senna leaf Not less
than 2.0%; Achyranthes aspera not more than 1.5%.; Curcuma longa not more
than 10%; Glycyrrhiza globra Not more than 2.5%.
III.
Water- soluble ash:
Boil the total ash for 5 minutes with 25 ml of water; collect the insoluble
matter in a Gooch crucible or on an ash less filter paper, wash with hot water,
and ignite to constant weight at a low temperature. Subtract the weight of
insoluble matter from the weight of the ash; the difference in weight
represents the water- soluble ash. Calculate the percentage of water- soluble
ash with reference to the air dried drug.
IV.
Sulphated ash:
A silica crucible was heated to redness for 10 minutes, allowed to cool in
desiccators and weighed. 1 g of substance was accurately weighed and
transferred to the crucible. It was ignited gently at first, until the substance
was thoroughly charred.
Then the residue was cooled and moistened with 1 ml concentrated sulfuric
acid, heated gently until white fumes are no longer evolved and ignited at 800°
± 25°C until all black particles have disappeared. The ignition was conducted in
a place protected from air currents.
The crucible was allowed to cool, and a few drops of concentrated sulfuric acid
were added and heated. Ignited as before, allowed to cool, and weighed. The
operation was repeated until two successive weighing does not differ by more
than 0.5 mg. calculate the percentage of Sulphated ash with reference to
the air-dried drug.
(E) Moisture content:
The moisture content is determined by following methods.
I.
Loss of drying:
Weigh a glass-stopper, shallow weighing bottle that has been dried under same
condition to be employed in the determination. Transfer to the bottle the
quantity of the sample, cover it and accurately weigh the bottle and the contents.
Distribute the sample as evenly as practicable by gentle side wise shaking to a
depth not exceeding 10 mm. Place the loaded bottle in the drying chamber (oven
or desiccators), remove the stopper and leave it also in the chamber. Dry the
sample to constant weight or for the specified time and at the temperature. After
drying is completed, open the drying chamber, close the bottle promptly and
allow it to cool to room temperature in desiccators before weighing. Weigh the
bottle and the contents.
II.
Karl Fischer apparatus:
This is a chemical method for determination of water content.
III.
Distillation:
The sample to be analyzed is placed in a flask together with suitable watersaturated immiscible solvent (Toulene, xylene, carbon tetrachloride) and pieces of
porous pot and is distilled. The water in sample has a considerable partial
pressure and co-dists with the solvent, condensing in the distillate as
immiscible layer.
IV.
Gas chromatographic method
(F) Refractive Index:
The refractive index is defined as the ratio of the velocity of light in vacuum to
velocity in the substance and is the ratio of the sine of the angle of incidence to
the site of the angle of refraction. It is measured by means of a Refractometer.
The refractive index changes if particular oil is mixed with another oil. The
measurements of the refractive index are particularly valuable for the purity
assessment of volatile oil and fixed oil.
Example:
Refractive index of cassia oil 1.61 and cinnamon oil 1.573- 1.600, etc.
(G) Volatile oil content:
The distillation method (Clevenger apparatus) is used to determine volatile oil
content. The weighed drug is placed in a distillation flask with water or a mixture
of water and glycerin and connected to receiver, which fitted with water and
connected to the condenser. On distillation, the oil and water condense and the
volatile oil which collects in the graduated receiver as a layer on top of the
water is measured.
I.
Swelling Index:
Weigh accurately 1 gm of plant material into a 25 ml glass stoppered measuring
cylinder. The internal diameter of the cylinder should be about 16 mm, the length
of the graduated portion about 125 mm, marked in 0.2 ml divisions from 0 to 25
ml in an upwards direction.
Ad 25 ml of water and shake the mixture thoroughly every 10 minutes for 1 hr.
allow to stand for 3 hrs at room temperature. Measure the volume in ml occupied
by the plant material, including any sticky mucilage. Calculate the mean value of
the individual determination.
Viscosity:
Viscosity is the quantity that describes a fluid's resistance to flow. Fluids resist the
relative motion of immersed objects through them as well as the motion of layers
with differing velocities within them.
Saponification Value:
Saponification value is the number of mg of potassium hydroxide required to
neutralize the fatty acids, resulting from the complete hydrolysis of 1g of the oil
or fat. It is a measure of the average molecular weight of all the
fatty acids present.
(e) Extractive values:
Extractive values of crude drugs are useful for their evaluation, especially when
the constituents of a drug cannot be readily estimated by any other means.
Further, these values indicate the nature of the constituents present in a crude
drug.
Determination of extractive values:
I.
Alcohol- soluble extractive:
Macerate 5 g of the air-dried drug, coarsely powdered, with 100 ml of alcohol of
the specified strength in a closed flask for 24 hrs. shaking frequently during 6 hrs.
and allowing standing for 18 hrs. Filter rapidly taking precautions against loss of
alcohol; evaporate 25 percentage of alcohol- soluble extractive with reference to
the air-dried drug.
Example:
Achyranthes aspera Not less than 4.0%; Glycyrrhiza globra Not less than 10.0%.
Water-soluble extractive:
Method-I:
Macerate 5 g of the air-dried drug, coarsely powdered, with 100 ml of chloroform
water of the specified strength in a closed flask for 24 hrs shaking frequently
during 6 hrs and allowing to stand for 18 hrs. Filter rapidly taking precautions
against loss of alcohol; evaporate 25 percentage of alcohol- soluble extractive
with reference to the air-dried drug.
Method-II:
Add 5 g to 50 ml ƒ water at 80°C in a stoppered flask. Shake well and allow
standing for 10 minutes; cooling to 15°C and adding 2 g kieseliguhr; filtering.
Transfer 5 ml of filtrate to a tarred evaporating basin 7.5 cm in diameter,
evaporate the solvent on a water- bath, continue drying for half an hour, finally
dry in a steam oven for 2 hrs and weigh the residue. Calculate the percentage of
water soluble extractive with reference to the air- dried drug.
Example:
Achyranthes aspera: Not less than 18.0%; Glycyrrhiza globra: Not less than 20.0%
Soxhlet apparatus:
They are continuous hot percolation process. They are useful not only extractive
but also small-scale isolation of chemical constituents.
(k) Spectroscopy:
It is the measurement and interpretation of electromagnetic radiation absorbed
or emitted when the molecules or atoms or ions of a sample move from one
energy state to another energy state.
I.
Ultra-violet and visible spectrophotometry:
When radiation is passed through a layer of a solution containing an absorbing
substance, part of the radiation is absorbed; the intensity of the radiation
emerging from the solution is less than the intensity of the radiation entering it.
The magnitude of the absorption is expressed in terms of the absorbance. A,
defined by the expression.
A = log10 (I0/I)
I0 = Intensity of the radiation passing into the absorbing layer.
I= the intensity of the radiation passing out of it.
Absorbance depends on the concentration of the absorbing substance in the
solution and thickness of the absorbing layer taken for measurement.
Conclusion:
Physical parameters include color, odor, appearance, clarity, viscosity, moisture
content, pH, disintegration time, friability, hardness, flowability, flocculation,
sedimentation, settling rate, Foreign matter,Optical rotation,Melting point, Ash
values, Moisture content,Refractive Index,Viscosity, Extractive values and
Spectroscopy.