Lab2 | Extraction .pdf
- 1. žInvoIves the separation of the medicinally active constituent of plants or animal tissues from the inactive or inert component by using solvent (s) and by using one of the standard extraction procedures .
- 2. – The products that obtained from plants are relatively impure liquids, semisolid or powders, intended only for oral or external use .These total extractive products are called Galenical, which came from the name Galen, the 2nd century Greek physician .
- 3. – A . cold method. 1- Maceration. 2- pecolation. – B . Hot method. 1- INFUSION . 2- Decoction. 3- digestion . 4- Continuous hot extraction methods. a- Ordinary Reflux Condenser: b- soxlet apparatus. C- clavenger .
- 4. Is the process whereby a substance is extracted from a mixture via cold solvent. The procedure carried out at room temperature (15-25 Cº).
- 5. – 1. Maceration :- Which include soaking of plant material with solvent until penetration of cellular structures and the active constituent softened and dissolved in the solvent. – The procedure include placing the plant material in a container and adding the , cover the container and leave it for a time which differ from 2- 4 days. After that pouring off the solvent , expressing the plant material and filter the solvent .
- 6. ž The procedure carried out at room temperature(15-25 ºC). ž Due to the difficulty to get the active constituent in one maceration process, the procedure may be repeated many times and the solvent obtained then mixed together. ž The solvent used in extraction is usually depend on the active constituent e.g. alkaloids and glycosides.by using alcohol and water in different proportion.
- 7. Water is used because if the alkaloids present in a salt form. They will dissolve in water. ž Non-polar solvents like chloroform are used for the extraction of volatile oils and terpenes and free alkaloids but not alkaloids salts.
- 8. • Can be used for heat sensitive substances . • Easy and cheap .
- 9. • Take a long time . • Non efficient . • Extracts small quantities .
- 10. In this method we are going to use a special apparatus which called perculator . The perculator has a porous diaphragm at the bottom . The procedure includes placing the powder plant material in the perculator and start adding the solvent from the upper end . While the solvent going downward to extract as much as possible the active constituent , then passing through the diaphragm.
- 11. * the plant material is much better to be soaked by the solvent about ½ hr. before starting the procedure. * the solvent used depends on the active constituent. The solvent called menstrum and extracts we get it called perculate and the plant material left is called mark material.
- 12. percolation
- 13. • We can use different types of solvents with different polarities to extract the active constituent. • Used for heat sensitive substances. • Easy and cheap.
- 14. • Large quantity of solvent is used. • Take a long time. • Extracts small quantities .nd inefficient.
- 15. 1- INFUSION In this method we have special container called “infusion pot ”. this method also used for the extraction of volatile oil. The procedure involve placing the plant material in the infusion pot then we add the solvent which is boiling water and cover with heavy lid which contain sieves , after the addition of the solvent , left for a while for the extraction of active constituent during that time the volatile oil evaporated with steam and deposited on the lid and condenses on the lid after that we take the solvent which contain the active constituent.
- 16. 2- Decoction In this method we place the powdered plant material in a container then add the solvent and place the container on a source of heat or direct flame then agitating until the active constituent will be dissolve in the solvent . This method is usually used for hard plant material like barks ,stems, and roots, which contain a lot of fibers . Here the solvent used depend on the active constituent and source of heat e.g. chloroform and ether can't be used because we use a direct source of heat.in addition to that the active constituent should be heat stable.
- 17. ž 3- Digestion In this method the plant material is placed together with the solvent and by application of gentle heat, so that the solvent will increase it's power for extraction and this method is used in cases were moderately temperature is required.
- 18. 4- Continuous hot extraction methods. a) Ordinary Reflux Condenser: we place the plant material in a round bottom flask with solvent and the round bottom flask is surrounded by a source of heat. The round bottom flask is attached to a condenser. We start to heat the flask and when the solvent reach it's point it will evaporate to the condenser were it condenses and return back to the flask.
- 20. • Small amount of solvent is used. • Used for toxic reagent , which can not be used in open-air system. • Continuous extraction method (good extraction).
- 21. 4- Continuous hot extraction methods. b) soxhlet apparatus: Soxhlet consists of a round bottom flask, extracting chamber , condenser ,and a thimble containing the powder plant material. when a solvent starts to boil it will evaporate to the condenser and dropped down to a porous paper (thimble).which contain the plant material, the solvent then will extract some of the active constituent and then it will go back to the round bottom flask through a siphon tube.
- 22. • We use a small amount of solvent (economic). • It is a closed apparatus so that it is used for dangerous organic solvents. • It can be used for the extraction of different active constituents by changing the polarity of the solvent. • It can be used for the extraction of active constituent decomposed by direct heat.
- 23. ž Ordinary reflux 1.Consisting from round bottom flask connected to a condenser. 2.The plant material is placed together with solvent in the round bottom flask. 3.The extract requires filtration. 4.The plant material is directly exposed to heat. ž Soxhlet 1.Consisting from round bottom flask connected with extracting chamber connected to a condenser. 2.The plant material is placed in the thimble separated from the solvent. 3.The extract not requires filtration. 4.The plant material is not directly exposed to heat.
- 24. ž Soxhlet
- 25. ž In this method we use a special apparatus which is called Clavengerit is used mainly for the extraction of volatile compound, e.g. orange peels has been used for the extraction of orange oil. and clove has been used for the extraction of clove oil .