Preparation of Crude Drugs

OCCURRENCE IN CRUDE DRUGS Crude drugs play a vital role in mediation. They are obtained rom various sour!es li"e plants# animals and minerals. They o!!ur in variety v ariety o morphologi!al orms depending on the nature o their sour!es. $arious !rude drugs are brought to the !ommer!ial mar"et in the ollo%ing !ommon orms& '. Entire o orm (. Cut# Cut# sli sli!e !ed d or bro" bro"en en or orm m ). *att *atted ed or pres presse sed d or orm m +. ,o%e o%ered o orm -. ,eele eled orm orm hen !rude drugs o!!ur o natural na tural origin o!!ur in the entire orm their morphologi!al an d sensory !hara!ters# li"e shape# te/ture# e/ternal mar"ings# ra!ture# !olour# odour and taste# are o immense signii!an!e in their identii!ation. Natural substances & '. Plant origin & leaves# lo%ers# seeds and bar"s. Or vegetable saps# e/tra!ts and se!retions. (. Animal origin & %hole animals# glands or organs# e/tra!ts and se!retions.

hen drugs o!!ur in po%ered orm they possess very e% ma!ros!opi! morphologi!al eatures o identii!ation other than some sensory !hara!teristi!s li"e !olour# odour and taste. '. Colour & Crude drugs may possess almost all types o !olours and shades o !olours. ,o%ders o leaves and herbs generally a!0uire a green to light green to bro%nish green

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!olour. •

,o%ered roots or rhi1omes usually possess a !ream to light bro%n to bro%n !olour.

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2ar"s in po%ered orm normally e/hibit a bro%n to deep bro%n !olour.

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oods appear o3%hite to !ream to bro%n in their po%ered orm.

(. Odour& Odour is produ!ed by the volatile !onstituents o many drugs. Intensity i the odour depends on the amount o volatile !onstituents the drug possesses. Odours are !hara!teristi! o individual drugs as they vary rom ea!h other in 0uality as %ell as intensity. Odour is an important parameter or distinguishing or even identiying many !rude drugs o natural origin. The terms !ommonly used or des!ribing odours in!lude& •

 Aromatic#  Aromatic# a pleasing s%eet s!ent.

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Spicy# Spicy# an odour similar to the !hara!teristi! !hara!teristi! smell o spi!es.  Alliaceous#  Alliaceous# a disagreeable odour similar to that o onions. Camphoraceous# Camphoraceous# a strong unpleasant odour.  Balsamic#  Balsamic# the !hara!teristi! smell o aldehydes. Characteristic# Characteristic# %hen the smell is very distin!t but %hen !annot be !orrelated to or or !ompared %ith any natural substan!e as the others.

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Taste& ,roper taste o a substan!e is per!eivable only %hen that substan!e or its !onstituents are soluble or partially soluble in the mouth luid. Tastes o various drugs are oten very useul in their identii!ation and evaluation. Tastes o various !rude drugs may be des!ribed as ollo%s& •

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 Insipid # or tasteless True tastes. tastes. True tastes !an be 4  Acidic 5sour6 4

Saline 5salty6

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Saccharine 5s%eet6

4  Bitter  5a  5a very unpleasant repulsive taste6 •

Odourous tastes# tastes# su!h as aromatic# aromatic# balsamic#  balsamic# spicy#  spicy# alliaceous#  alliaceous# camphoraceous et!.

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Sensual tastes# tastes# su!h as 4  Mucilaginous 5a  Mucilaginous 5a sot slimy eeling6 4

Oily 5a bland smooth eeling6

4  Astringent 5a pu!"ering or !ontra!ting eeling6 4  Pungent  5a  5a %arm biting sensation6 4  Acrid 5an unpleasant irritating sensation6 4  Nauseous 5a  Nauseous 5a taste %hi!h e/!ites vomiting6

+. Shape & Drugs o!!ur in various shapes# or e/ample&

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Cylindrical  e.g.  e.g. sarsaparilla

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Sub cylindrical  e.g.  e.g. podophyllum

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Conical  e.g.  e.g. a!onite

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Ovoid  e.g.  e.g. 7alap

4  Dis shaped  e.g.  e.g. nu/3vomi!a

-. External markings & Su!h as %rin"les# issures# nodules# ring li"e mar"ings# pro7e!tions and s!ars are ound in the !rude drug materials.

8. Fracture & It reers to the %ay the plant part p art brea"s %hen sub7e!ted to sui!ient pressure. Certain !hara!teristi!s are as ollo%s& 4

Complete 5brea"ing Complete 5brea"ing !lean a!ross6

4  Incomplete 5brea"ing only parts6 4

Short  5smooth  5smooth brea" %ith a 0ui!" snap6

4  !ibrous 4

Splintery 5having larger and smaller parts6

4  Brittle 5easily bro"en or e/ample %hen dropped onto hard sura!e6 4

Tough 5brea"ing %ith dii!ulty6

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"ea 5brea"ing %ith little eort6

,RE,9R9TION O: CRUDE DRUGS 2eore sending the !rude drug or sale to the mar"et# it should be prepared properly so that its a!tive !onstituent and appearan!e remain same and does not deteriorate beore use. ,reparation o !rude drugs or the !ommer!ial mar"et involves !olle!tion# drying# garbling# 0uality !ontrol#  pa!"aging# storage and preservation. '. Collection: Colle!tion means a!!umulation or pro!uring o the drug rom its natural habitat or natural sour!es. The ollo%ing a!tors must be !onsidered during !olle!tion&

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rong identii!ation o the sour!e

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9dmi/ture %ith similar loo"ing plants

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Colle!tion rom too old or too young or too diseased plants.

Suitable time for collection The amount o a !onstituent is usually not no t !onstant throughout the lie o a plant. p lant. The proper time o harvesting or !olle!ting is parti!ularly important be!ause the nature and 0uantity o !onstituents vary greatly in some spe!ies a!!ording to the season. The most advantageous !olle!tion time is %hen the part o the plant that !onstitutes the drug is highest in its !ontent o a!tive prin!iples and %hen the material %ill dry to give the ma/imum 0uality and appearan!e. 4  #oots and  #oots and rhi$omes are rhi$omes are !olle!ted at the end o the vegetation period# i.e. usually in the autumn. In most !ases they must be %ashed ree o adhering soil and sand. 4  Bar  is  is !olle!ted in the spring. 4  %eaves and  %eaves and herbs are herbs are !olle!ted at the lo%ering stage. 4  !lo&ers are  !lo&ers are usually gathered %hen ully developed. 4  !ruits and  !ruits and seeds  seeds are  are !olle!ted %hen ully ripe. ethods of collection The method o !olle!tion either rom %ild sour!e or !ultivated sour!e depends on the type o the drug and also on the pharma!euti!al re0uirement. Crude drugs may be !olle!ted by hand labour or me!hani!al devi!es. 4  'and picing  is  is used %hen the drug is !olle!ted rom mi/ed vegetation and s"illed sele!tion o plant parts is re0uired.

4  Mechanical devices li"e devices li"e mo%ers# binders# pi!"ers redu!e !ost and save time. :ruits and seeds are !ut %ith mo%ers and binders. :lo%ers %ith land s!oop or rotary lo%er pi!"er and underground parts by potato po tato diggers# tra!tors et!. (. !r"ing: Colle!ted plant parts !ontain -- to ;(< ; (< %ater. This high per!entage o %ater en!ourages en1ymati! and other !hemi!al rea!tions and gro%th o ba!teria# moulds# yeasts %hi!h may !hange their !hara!teristi!s. !ha ra!teristi!s. Drying the plant parts removes sui!ient moisture to insure good 0uality and prevents moulding# the a!tion o en1ymes# ba!teria and !hemi!al and other possible !hanges. Drying also i/es the !onstituents and a!ilitates grinding and milling as %ell as ma"es the !rude drugs more !onvenient or !ommer!ial handling. T%o main  prin!iples o drying are temperature !ontrol and regulation o air lo%. Drying operation operation depends on nature o the materials to be dried and the desired appearan!e o inished  produ!t. T%o types o drying are& •

Open air drying # %hi!h may be done in the sun or in the shade. Sun drying is adaptable to those drugs %hi!h are not unavourably ae!ted by the dire!t a!tion o sun. Shade drying is employed or those drugs in %hi!h retention o the natural !olour is desirable and %hose !onstituents are adversely ae!ted on the e/posure to sunlight.

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 Arti(icial drying # %hi!h involves some devi!es in %hi!h heat and air ventilation are

maintained me!hani!ally. In a dried drug the en1ymes are not destroyed but only rendered ina!tive due to the lo% %ater !ontent. 9s soon as %ater is added# they be!ome a!tive again. =en!e# dried drugs must be  prote!ted rom moisture during storage. ). #arbling: Garbling is the removal o e/traneous matters. This is done to some e/tent during !olle!tion but should be done ater the drug is dried and beore pa!"aging. Common e/traneous matters are other parts o the plants> rotten# dirt and soil parti!les> some parts o dierent plants> and a!!idental or added adulterants. It !an be done in t%o %ays& •

 Manually#  Manually# by hand pi!"ing.

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 Mechanically#  Mechanically# su!h as bar magnets !an be used to remove iron parti!les# sieves are

used to separate dirt and other parts o the plants# !urrents o air air removes !huy and other light substan!es present in the drug and soil parti!les !an be removed during !olle!tion by %ashing %ith %ater. Garbling is ne!essary to produ!e !lean drug> to minimi1e damage to the grinding ma!hine> to  prote!t die and pun!hes o tablet ma!hine> and to improve the aestheti! 5mar"eting6 value. +. $ualit" control: ?uality !ontrol tests are applied to small samples o large !onsignments o drugs. =o%ever the samples ta"en must be representative o the %hole !onsignment. Some  preliminary 0uality !ontrol measures should be adapted to most !rude drugs beore they are sent to the !ommer!ial mar"et. ?uality !ontrol !reates an e/tra branding and ensures good  pri!e o the produ!t. Several tests in 0uality !ontrol are& 4 ,reliminar ,reliminary y e/amination e/amination or the the general general appearan!e appearan!e o the sample sample by using using mi!ros mi!ros!opi! !opi! and sensory !hara!ter. 4 Determ Determina inatio tion n o orei oreign gn organi organi!! matter matterss by manual manually ly pi!"i pi!"ing. ng. 4 Determinat Determination ion o the amount amount o moisture moisture present present in the the dried dried drug by a simple simple @loss on drying methodA. 4 Some 0uantit 0uantitative ative !hemi!al !hemi!al tests tests to determine determine the the amount amount o the a!tive a!tive prin!ip prin!iples les in in the sample. -. Packaging: The prin!iple o pa!"aging is to provide an ample prote!tion to the drug as %ell as to give e!onomy o spa!e. ,a!"aging ensures ease in handling and transportation o  produ!t. The !hoi!e o pa!"age to be used depends on the ollo%ing& 4 Nat Nature ure o o the the !rud !rudee dru drugs gs 4 E/te E/tent nt o hand handli ling ng it may may go go 4 ,rod ,rodu! u!tB tBss in inal al disp dispos osit itio ion n Drugs that are traded in nearby mar"et and do not involve transportation or mu!h handling or storage are pa!"ed loosely in temporary ordinary o rdinary pa!"aging. Drugs that undergo transportation#

handling and storage are pa!"ed in %aterproo and strong !ontainers or pa!"ed in a !ompa!t %ay. E/amples regarding pa!"aging are as ollo%s& 4 Senna# belladonna belladonna and and stramon stramonium ium leaves leaves are baled baled %ith %ith po%erul po%erul balers balers and made made into into a solid mass and then !overed by suitable %ater proo !overs. 4

Drugs that are are sus!ept sus!eptible ible to to moisture moisture## su!h as digital digitalis is and ergot# ergot# are pa!"ed pa!"ed into into moistur moisturee  proo !ans.

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E/tra!t E/tra!t o gums and and resins resins are are pa!"ed pa!"ed in tin lined lined bo/es bo/es and and tin !ans or or metalli metalli!! !ontainers. !ontainers.

8. Storage and preser%ation of crude drugs: ,roper storage and preservation are important a!tors in maintaining a high degree o o  0uality o drugs. In order to "eep !rude drugs as long as possible& 4 It is is essenti essential al to store them in a dry !onditi !ondition on in !areully !areully !losed !losed !ontainers. !ontainers. 4 It is also advisa advisable ble to e/!lude e/!lude light# light# be!ause be!ause 3 even i it does does not ae!t the a!tive a!tive !onstituents 3 it almost al%ays !auses !hanges in the ap pearan!e o the drug# espe!ially loss o !olor. 4 It is is also also ne!es ne!essar sary y to prote prote!t !t the the drug drug again against st inse inse!t !t atta! atta!". ". 4 Certai Certain n drugs# drugs# su!h su!h as biolog biologi!s i!s## must be be stored stored at a tempe temperat rature ure bet%ee bet%een n (⁰ and ;⁰ C sin!e high temperature a!!elerate all !hemi!al rea!tions# in!luding those involved in deterioration.