GALENICALS

1. GALENICALS N.SANTHI PRIYA ASSOCIATE PROFESSOR DEPARTMENT OF PHARMACEUTICS

2. TERMINOLOGY • EXTRACTION : • It is the process in which the animal or plant tissues are treated with specific solvents whereby the medicinally active constituents are dissolved out, cell tissues and most of the inert components remain undissolved • Galenicals : The crude extract is impure. It includes tinctures,liquidextracts,semisolid extracts and powdered extracts used for oral or external use known as galenical named after a renowedgreek physician Galen

3. EXTRACTION • Extraction term Pharmaceutically involves the separation of medicinally active portions of plant or animal tissues from the inactive or inert components by using selective solvents in standard extraction procedures.

4. TERMINOLOGY • Menstruum : solvent used for the extraction purposes is known as menstruum • Marc: residue left after extracting the desired constituents is known as marc • Macerate : It is the solution of soluble constituents of drug in a menstruum • Expression: Extraction carried out by applying mechanical force which squeezes out juices, oils from vegetable or animal tissues termed as expression

5. METHODS OF EXTRACTION • ACCORDING TO THE METHOD OF DRUG-MENSTRUUM CONTACT THE EXTRACTION PROCESS IS DIVIDED INTO DIFFERENT TYPES

6. MODIFICATIONS • Macerartion – vacuum maceration • Percolation - Repercolation and hot percolation

7. Factors Affecting Extraction NATURE OF CRUDE DRUG • If hard and tough (NUX VOMICA) use percolation • If soft and parenchymatous (Gentian) use maceration • If unpowderable (squill,bael) use maceration • If unorganized (Benzoin) use modified maceration • Easily water soluble constituents(Kalmegh) use maceration process NATURE OF CONSTITUENTS • Costly drugs- percolation • Therapeutic value and yield : • Certain drugs are medicinally unimportant. EX:Bitter tonic(gentian) Carminative(valerian) Coloring agent(cochineal) Flavoring agent(Lemon) may be extracted by MACERATION • If drugs have medicinal value(Belladona) then percolation process should be used • Gums and proteins undergo precipitation at high alc.conc.so hydro alcoholic solvents are to be used

8. Factors Affecting Extraction MENSTRUUM • It should be good for the constituents present in the crude drugs • It should not get vaporized during maceration but for the preparation of concentrated extracts or dry extracts it should get easily vaporized • It should be of low viscosity • Should not allow growth of micro organisms • Physicochemical inert, non toxic, economic, easily available STABILITY OF DRUG Volatile and heat sensitive cant be extracted by heat So, hot continous extraction process should be avoided by thermolabile drugs Antimicrobial action by taking alcohol as alternative solvent CONCENTRATION OF PRODUCT • Dilute products – infusion • Tinctures – infusion or maceration • Concentrated products (LIQUID EXTRACTS OR DRY EXTRACTS) – percolation or modified processes Availability of skilled labour. Percolation process requires skilled person than maceration process Time taken for the extraction Percolation is lengthy process than maceration process

9. The MENSTRUUM ( Solvents) IDEAL QUALITIES OF SOLVENTS • Cheap • Nontoxic • Stable Chemically and physically inert Neutral to reaction Not too volatile Non inflammable • Selective Remove only desired active constituents • Plentiful • Low specific heat – to reduce the cost of removal • Low viscosity – facilitates leaching of solute from the tissues

10. Water

11. Water

12. ALCOHOL

13. ALCOHOL

14. WATER – ALCOHOL MIXTURE (HYDROALCOHOLIC SOLVENTS) • Most widely used • It possess the combined solvent action of water and alcohol • No microbial growth • It is solvent as well as preservative • Chloroform,Ether,petroleumether,benzene can be useful for fats and waxes GLYCERIN ORGANIC SOLVENTS ACIDIFIED WATER ALKANISED WATER

15. FRESH INFUSION • They can also be prepared by DILUTING 1 VOLUME OF CONC.INFUSION TO 8 TO 10 VOLUMES WITH WATER • They are liable to microbial growth • So they should be used within 12 hours after compounding • To retard the microbial growth it should be stored in cold place EXAMPLES: • Compound chirata infusion IP ( prepared by diluting 12.5ml of concentrated chirata infusion with water to 100ml) BITTER TONIC with dose 15-30ml • Orange pill infusion BPC • Senega infusion BPC • Infusion of quassia • Infusion of senna

16. CONCENTRATED INFUSION • THEY are 8 times more concentrated than fresh infusions • If prepared using small parts of menstruum it is insufficient to provide sink condition for rapid dissolution of drug • They contain 20 to 25% alcohol which increases the solvent action by acting as co-solvent • Alcohol also acts as preservative • It improves the dispersibility of during preparation of fresh infusion by dilution method • Dose of concentrated infusion range from 2 to 5ml PREPARATION METHODS: • Concentration by evaporation • Multiple maceration technique • Reserved percolation technique Official examples: • Concentrated compound infusion of chirata • Concentrated compound infusion of gentian

17. DECOCTION

18. DECOCTION • This process is used for vegetable drugs containing water soluble and heat stable constitutents • A freshly prepared decoction should only be dispensed and the same must be consumed within 24hrs • At present no decoction is official in IP or BP • Ex : DECOCTION OF IRISH MOSS B.P.C

19. DIGESTION • It is a modified form of maceration • Drug + menstruum is kept hot between 40 - 60°C • If volatile menstruum is used then digestion vessel should be connected to reflux condenser • Menstruum can be recovered and returned • Longer time is required for extraction (AS TEMPERATURE USED IS LOW) when compared to infusion and decoction which uses high temperature

20. MACERATION • Maceration involves softening of drug by keeping it in intimate contact with menstruum in a closed vessel for period of 2 to 7 days with occasional agitation • The infusion and decoction is only applicable for extracting highly water soluble constituents • In maceration the contact period is longer which may be upto 7days

21. The maceration is further divided into • Simple maceration for extraction of organized drugs • Maceration with adjustment for unorganized drugs • Multiple maceration for concentrated extracts • Vacuum maceration

22. Percolation • Ground solids were mixed with appropriate solvents to make them damp • Allowed to stand for 15min • Transferred to a percolator and packed • Sufficient prescribed solvent is added to saturate the solids • The solids are allowed to macerate for 24hrs or for a prescribed time • The percolate are collected • If necessary percolate is diluted with the solvent to produce a solution to meet the standards

23. INFUSION POT PERCLATOR PACKED WITH CRUDE DRUG

24. PERCOLATR WITH STEAM JACKET SIMPLE PERCOLATOR

25. PERCOLATOR FOR VOLATILE MENSTRUUM PERCOLATOR FOR OPERATION UNDER REDUCED PRESSURE

26. BASKET PRESS HOT CONTINOUS PERCOLATION

31. Comparison between the methods of extraction

32. EXTRACTIVE PREPARATIONS

33. TINCTURES • Defined as alcoholic or hydroalcoholic solutions prepared from vegetable materials or chemical substances(Iodine tincture) • Potency can be adjusted following the assay • 10gm drug/100ml tincture (Potent tincture)

34. Fluid extracts • Defined as liquid preparations of vegetable drugs containing alcohol as a solvent or as preservative or both • Each ml fluid extract = 1gm standard drug

35. EXTRACTS – FORM WISE Solid/Pilular extracts • Have consistency to be used as pills • Also suited for ointments and suppositories preparation • Ex:PureGlycyrrhiza extract

36. EXTRACTS – FORM WISE Powdered extracts • Better suited to be incorporated as dry formulations as in capsules • Drugs that contain inactive oily or fatty matter should be defatted inorder to avoid possible loss of activity of the active constituents • Ex: • Belladona extract USP

37. EXTRACTS – FORM WISE Semi liquid extracts or extracts of syrupy consistency • They are used to prepare pharmaceutical preparations • Mostly they are medicinal agents with therapeutic property as well as they are used as vehicles