Herbs as raw material.pdf

Herbal Drug Technology Unit I

1. Herbal Drug Technology
B. PharmVI Sem
Dr. SnehalS. Manekar
Assistant Professor
Dr. Rajendra GodeInstitute of Pharmacy,
Amravati, Maharashtra

2. Topics
No. Subtopics
UNIT-I Herbs as raw materials
Biodynamic Agriculture
Indian Systems of Medicine
UNIT-IINutraceuticals
Herbal-Drug and Herb-Food Interactions
UNIT-IIIHerbal Cosmetics
Herbal excipients
Herbal formulations
UNIT-IVEvaluation of Drug
Patenting and Regulatory requirements of natural products
Regulatory Issues
UNIT-V General Introduction to Herbal Industry
Schedule T –Good Manufacturing Practice of Indian systems of medicine.

3. UNIT I-Herbs as raw materials
•Anyseed-bearingplantthatdoesnot
haveawoodystemanddiesdownto
thegroundafterflowering.
•Anyplantwithleaves,seeds,or
flowersusedforflavouring,food,
medicine,orperfume.
Herbal medicine
•Thedefinitionofherbalmedicineis
theuseofplantstopreventand
treatanillness,ortoachievegood
health
HERBS
DEFINITIONS

4. DEFINITIONS
•Herbalpreparationsarethebasisfor
finishedherbalproductsandmay
includecomminutedorpowdered
herbalmaterials,orextracts,
tincturesandfattyoilsofherbal
materials.
Herbal products
•Itconsistofoneormoreherbal
preparationsmadefromoneormore
herbs(i.e.fromdifferentherbal
preparationsmadeofthesameplant
aswellasherbalpreparationsfrom
differentplants
Herbal preparations

5. Selection, identification and authentication of herbal drugs
•Quality control of herbal drugs and herbal isolates (tinctures, extracts, and
essential oils) is done according to the requirements of Pharmacopoeia and
other relevant regulations.
•The Pharmacopoeia monographs,
•Monographs European Medicinal Evaluation Agency (EMEA),
•World Health Organization (WHO),
•European Scientific Cooperative on Phythotherapy(ESCOP),
•Commission E (The German Commission E is a scientific advisory board ).

6. Selection, identification and authentication of herbal drugs
Identification tests should be specific for the herbal material and are usually
a combination of three or more of the following:
➢macroscopic characters
➢microscopic characters
➢chemical testing
➢chromatographic confirmation
➢Biological evaluation

7. Processing of herbal materials
1. Collection of drugs:
2. Time of collection
3. Harvesting
4. Primary processing
5. Drying
6. Specific processing
7. Garbling
8. Packing
9. Storage

8. Processing of herbal materials
Cultivationofmedicinalplantsisalsoknownaspropagation,Whichcan
bedonebysexualandasexualmethods.
Processingofherbalrawmaterialsinvolvesvariousstagesfromwhichthe
crudedrugsundergoafterharvesting.Itcanbeclassifiedintoprimaryand
secondaryprocessingwhicharefurthersubcategorizedasfollows.

9. Processing
Primary
Garbling
Washing
Parboiling
Leaching
Drying
Secondary
Cutting
Aging
Baking
Boiling
Stir frying
Fumigation
Extraction

10. Garbling(Sorting)
Thisprocesshelpsinensuringthepurityandcleanlinessoftheharvestedmaterial.
Dirtlikesoil,dust,impuritieslikeinsects,deadtissuesandresidualnonmedicinal
plantsareseparatedfromtherawmaterial.Theprocessdependsonthepartofthe
planttobeprepared.Theprocessmayinvolveproceduressuchasremovingdirtand
foreignsubstances,discardingdamagedparts,peelingofbarks,sieving,trimming,
removalofhairsfromroots,removalofseedsfromfruits,strippingofleavesfrom
stems.Thismaybedonebymechanicalmeansbutinsomecasesitisusually
performedmanuallybyhands.
Primary
Proces
s

11. Washing:
Aftergarblingtheherbalrawmaterialshouldbecleanedwelltoremovethe
tracesofremainingsoil,dirtandotherimpuritiesfromthesurface.The
roots,rhizomesandtubersarewashedwithcleanwater.Duringthewashing
process,scrappingandbrushingmaybenecessary.

12. Parboiling (Blanching) :
Afterwashing,certainherbalrawmaterialsneedtoundergoparboiling
processinwhichtheyareputinboilingwaterforashortperiod.
Thismayhelpinimprovingthestoragelifeoftherawmaterialandprevent
insect/mouldcontamination.
Itmayalsofacilitateinfurtherprocessingsuchasremovalofstubborn
impuritiesaswellasoutercoats/coveringofrawmaterials.
Leaching:
Someimpuritiescanberemovedbysubjectingtheplantmaterialunder
runningwaterknownasleaching.Howeverthedurationofleachingshould
becontrolledtopreventthelossofchemicalconstituentspresentinthe
drug.
Dr SnehalS Manekar

13. Drying:Insomecases,theplantmaterialshouldbethoroughlydriedafter
washinginordertopreventthedeteriorationanddegradationofactive
constituents.Theymustbedriedassoonaspossibletoremovemoistureand
reducethedamageduetomicrobialormouldinfestation.
Dryingalsopreventstheactivationofcertainenzymeswhichmayotherwise
degradetheactiveingredientsandalsofacilitategrindingandmillingoftheraw
material.Dependingonthedrug&natureofingredients,differentdrying
methodsareusedasfollows:

14. I)Naturaldrying
a)Sundrying:
Mostherbalrawmaterialcanbedriedinopenairunderdirectsunshine
providedtheclimateissuitable.Thedurationofdryingprocessdependson
thephysicalstructureoftheplantmaterialandweatherconditions.The
plantmaterialshouldbespreadoutinthinlayers,careshouldbetakento
preventcontaminationbydietimpurities.Whiledryingtheplantmaterial
shouldalsobeprotectedfrominsects,Birds,rodents,pestsandother
domesticanimals.
b)Shadedrying:
Somemedicinalplantscannotbedirectlyexposedtosunlight,henceneedto
bedriedundershade.Thisdryingprocessisslowbuthelpsinminimizing
lossofcolour,volatileoilsandaromaticcomponentsfrombeingevaporated.

15. II)Artificialdrying
Dryingbyartificialheatismorerapidthanopenairdryingandisnecessaryinrainy
seasonandregionswherethereishighhumidity.Thetemperatureandequipment
usedfordryingdependsonthephysicalandchemicalnatureofthedrugandits
constituents.Variousequipment'ssuchastraydryers,spraydryers,vacuumdryers
areused.Overheatingmayleadtoexcessivelossofvolatilecomponentsaswellas
decompositionofchemicalconstituents.Thetemperatureshouldbekeptbelow60
0Cwhereverpossible.
a.Traydryers(Oven)
Thedrugswhichdonotcontainvolatileoilsandarequitestabletoheatorwhich
needdeactivationofenzymesaredriedintraydryers.
Inthisprocess,hotairofthedesiredtemperatureiscirculatedthroughthedryers
andthisfacilitatestheremovalofwatercontentofthedrugs(belladonnaroots,
cinchonabark,teaandraspberryleavesandgumsaredriedbythismethod).
b.Vacuumdryers
Thedrugswhicharesensitivetohighertemperaturearedriedbythisprocess,
e.g.Tannicacidanddigitalisleaves. Dr SnehalS Manekar

17. c.Spraydryers
Fewdrugswhicharehighlysensitivetoatmosphericconditionsandalsoto
temperatureofvacuum-dryingaredriedbyspray-dryingmethod.The
techniqueisfollowedforquickdryingofeconomicallyimportantplantor
animalconstituentsratherthancrudedrugs.
Ex.Papayalatex,pectin,tanninsetc.

18. Thesecondaryprocessingdiffersfromoneherbtoanotherdependingon
thenatureofactiveingredientsaswellastherapeuticproperties.Secondary
processingincludestechniquessuchasremovalofforeignsubstances,
preventionofmicrobialpresence/infestation,enhancingtheefficacyof
drugs,reducingthetoxicity,extractionusingsuitablesolvents,conc.&
dryingofextracts.Thesearefurtherstandardizedbydifferentmethods.
a.Cutting,SectioningandCommunition:
Afterthoroughlydrying,theherbalmaterialsareprocessedbycuttingand
sectioningintosmallersizeswhichareconvenientforstorageaswellas
extraction.Varioussizescanbeobtaineddependingonthepartofherband
extractionmethodsused.Itmaybesmallparticles,coarsepowderorfine
powder.
Secondary
processing

19. b.Aging/Sweating:
Agingreferstostoringtherawmaterialforaspecifiedtimeafter
harvesting.Itisgenerallydoneundersunorinshadeforuptoayear.
Duringtheprocessofagingexcessivewaterisevaporated&enzymatic
reactionsmayoccurtoalterthechemicalcompositionofherbalmaterial.
Example:
Cascarabarkshouldbeagedforatleastoneyearpriortouseinmedicinalpreparations
toreduceitsirritanteffects.Sweatingisdonebysubjectingtheherbalmaterialsata
temperaturebetween45to65°Cwithhighhumidityforaperiodrangingfromone
weektofewmonths.Theherbalmaterialsarestackedbetweenwoollenblanketsor
otherkindofcloth..Thesweatingprocessisconsideredahydrolyticandoxidative
processinwhichsomeofthechemicalingredientsoftheherbsarehydrolysedor
oxidised.

20. c.Baking/Roasting:
Itisaprocessofdrugheatingwheretheherbalmaterialisheatedinovens.
Thetemperatureofheatinganddurationofbaking/roastingvaryfromone
herbalmaterialtoanotheruntilthedrugdevelopsaspecificcolour.
Example:
Nutmegisroastedtilltheyturntoyellowishbrowncolour.
d.Boiling/Steaming:
Intheboilingprocessthedrugiscookedinwateroranyotherliquidsolventsuchas
vinegar,wine,milkoranimalurine.
Example:Acoruscalamusrhizomeisboiledincow’surinetoenhanceitsanticonvulsanteffects.
Inthesteamingprocesstheherbalmaterialiskeptincontactwithsteamusingasteamer
resultingindevelopmentofmoisttexture.

21. e.Stirfrying:
Intheprocessinwhichtheherbalmaterialsareputinapotoffryingpan
andcontinuouslystirredortossedforaspecificperiodunderheatuntilthe
externalcolourchanges,charredorevencarbonized.Tofacilitateuniform
heating,thedrugmaterialcanbeadmixedwithsand,talcorclay.
Example:
Liquoricerootsandrhizomesarestirfriedwithhoney.
f.Fumigation:
Sometimestheharvestedrawmaterialsaresubjectedtofumes.Fumigation
withsulphurdioxideiscommonlyemployedforsomemedicinalherbsfor
thepurposeofpreserving,colour,improvedappearance,bleachingand
preventingthegrowthofinsectsandmoulds.