Notes

For plant profile summary Click here.
For note about Thin Layer Chromatography Click here.
For note about Medicinal Plants of Nepal Click here.
For note about Scope of Pharmacognosy Click here.

Experiment 15 Study of extraction process using Soxhlet apparatus

Experiment 15

Study of extraction process using Soxhlet apparatus

Materials required:

Sample, Round buttomed flask, condenser, heating mantle, ethanol, thimble, boiling chips

Theory

Extraction is defined as the process in which the soluble constituents are separated from the insoluble residue by the treatment of suitable solvents or mixture of solvents.

The soxhlet extraction is the process of continuous extraction in which the same solvent is circulated though the extractor several times.

Initially the solvent is evaporated. Its vapor is carried to the condenser and the condensed liquid is returned to the drug (packed in thimble) for continuous extraction.

      Procedure

·         About 5 gm of sample leaves were cut into small pieces and were grinded on mortar and pestle.

·         The thimble was filled with this sample.

·         Ethanol was poured into the round buttomed flask till it is occupied with more than half in volume.

·         3-5 boiling chips (broken porcelain) was added.

·         The round buttomed flask was placed on the heating mantle.

·         Soxhlet extractor was connected with the flask .

·         Condenser was connected to the extractor and the apparatus was stabilized using support stand.

·         The heating mantle and the heat was increased gradually. The solvent was brought only to the vaporization stage but not to a rolling boil.

·         Heat was adjusted to achieve regular flushing.

·         The extraction was allowed till the colorless flushing appeared.

·         Heating was switched off and water flow was stopped once the round buttom flask was cooled down.

·         The extract was collected by evaporating the solvent on the water bath.

Result:

Hence, extraction was carried out using soxhlet apparatus.

Precautions:

·         Heat sensitive, explosive and inflammable substances should not be kept near the apparatus.

·         The apparatus should be disassembled only after the apparatus cools down.

Experiment 14 Study of microscopical features of Mentha

Experiment 14

STUDY OF MICROSCOPICAL FEATURES OF MENTHA

Microscopical Features

• -          Mentha consists of diacytic stomata which are present mostly on the lower side.
• -          Covering trichomes are 3-8 celled uniseriate having pointed apex and longitudinally striated cuticle.
• -          The larger glandular trichome consist of unicellular stalk and glandular head composed  of 8 radiating cells.
• -          Palisade is single layered.

Chemical constituents

• -          Menthol
• -          Menthone
• -          Cineole

Pharmacological action/ Uses

• -          Carminative
• -          Flavoring agent
• -          Stimulant
• -          Rheumatism
• -          Neuralgia
• -          Headache
•       Toothache

Experiment 13 Study of macroscopical features of Mentha

Experiment 13

STUDY OF MACROSCOPICAL FEATURES OF MENTHA

Synonyms : Spear mint, mint, Pudina (vernacular name)

Biological source

•                 Scientific name: Mentha spicata
•                 Part used: dried leaves and flowering tops
•                 Family: Labiateae

Organoleptic evaluation

                Color: green to greenish brown

                Odor: aromatic and characteristic

                Taste: characteristic

                Shape: ovate

                Size: ___length, ___breadth

Other macroscopical Features

• -          The base apex is obtuse type.
• -          The margin is serrate to dentate type.
• -          The leaf possesses reticulate venation.
• -          The leaf surface is pubescent and is often crumpled.

Experiment 12 Study of microscopic features of Fennel

Experiment 12

STUDY OF MICROSCOPICAL FEATURES OF FENNEL

Microscopic features

• -          The epidermis consists of thick cuticle.
• -          The mesocarp is composed of parenchyma, vascular bundles and elliptical vittae.
• -          The parenchymatous region in the vascular region are much thickened, reticulate and lignified.
• -          Four elliptical vittae are present at the dorsal surface while two on the commissural surface of each mericarp.

Chemical constituents

-          Anethole

-          Fenchone

Uses

• -          Carminative
• -          Flavoring agent
•          Use in many dental and mouth wash formulations

Experiment 11 Study of macroscopic features of Fennel

Experiment 11

STUDY OF MACROSCOPICAL FEATURES OF FENNEL

Synonyms : Fennel fruit, Foeniculum

Biological source

•                 Scientific name: Foeniculum vulgare
•                 Part used: dried ripe fruit
•                 Family: Umbelliferae

Organoleptic evaluation

                Color: greenish  brown to yellowish brown

                Odor: agreeable and aromatic

                Taste: distinct, sweet and aromatic

                Shape: slightly curved and oval

                Size: ___length, ___breadth

Other macroscopical Features

• -          It occurs as entire cremocarp with pedicel attached.
• -          A bifid stylopod is present at the apex
• -          The cremocarp is composed of two mericarps.
• -          Each mericarp possess glabrous surface, and five straight, prominent, straw colored primary ridges.

Experiment 10 Study of microscopic features of Vinca

Experiment 10

STUDY OF MICROSCOPICAL FEATURES OF VINCA

Microscopical Features

• -          The leaf possess single layered epidermis with cruciferous (anisocytic) stomata.
• -          Few unicellular covering trichomes are present.
• -          Palisade  is single layered.
• -          Spongy layer is 5-8 cell layered.

Chief chemical constituents

• -          Vinblastine
• -          Vincristine

Uses

• -          Hodgkins disease
• -          Choriocarcinoma
• -          Acute lymphocytic leukemia in children
• -          Small cell lung cancer
• -          Cervical cancer
• -          Breast cancer