14

Curryleaf

J.SalikuttyandK.V.Peter,KeralaAgriculturalUniversity

Introduction

Curryleaf(MurrayakoenigiiSpreng)(Syn.BergerakoenigiiKoen(N.O.Aurantiaceae),ChaleoskoenigiiKurzexSwingle)isaperennialleafvegetable.ItbelongstothefamilyRutaceaeandisnamed‘Murraya’afterJohnAdamMurray,ProfessorofBotanyatGottingenandeditorofmanyofLinnaeus’sworks.Itisanativeofthemountainouspartsandgrowsuptoanelevationof1500m.ThecurryleafisfoundgrowingthroughoutIndiaincludingtheAndamanIslandsuptoanaltitudeof1500m.1ItisrecordedwildinGarwhaltoSikkim,Bengal,Assam,theDeccan,Circarmountains,Westernghats,CoromandelandTravancore–Cochin.Theleavesoftheplantareusedextensivelyforseasoningandflavouringdishes.CurryleafisexportedascurryleafandascurryleafoilfromIndia(Table14.1).

Theleavesoftheplantareemployedextensivelyasflavourantincurrieslike‘dal’,‘SouthIndianSambar’,‘rasam’andchutneysandmulligatawny.Groundcurryleafwithmaturecoconutkernelandspicesformsanexcellentpreserve.‘Veppilakkatti’,averyfamouspreparationofSouthIndia,canbemadewiththefollowingingredients:curryleaf(100g);tenderleavesofmaltalemon(50g);commonsalt(50g);seedlesstamarind(40g);redchillipowderwithoutseed(20g);fenugreekpowder(2g);asafoetida(6g);blackpepperpowder(2g);gingellyoil(10g).Forpreparing

Table14.1ExportofcurryleaffromIndiaduring1993–94to1997–98(quantityintonnes,valueinRs.1000)

Product

1993–94

Qty Value

1994–95

Qty Value

1995–96

Qty Value

1996–97

Qty Value

1997–98

Qty Value

Curryleaf

15.2 989.7

10.9 618.8

39.01604.4

68.62185.1

152.83334.2

Curryleafoil

–

–

–

–

–

–

0.4 115.4

–

–

Source:SpicesStatistics,IVtheditionbySpicesBoard,MinistryofCommerce,GovernmentofIndia,Cochin,682025.

Curryleaf

PAGE

169

PAGE

170

Handbookofherbsandspices

‘veppilakkatti’,frytheasafoetidaingingellyoilandpowderit.Mashthetenderleavesofmaltalemoninamixiandremoveallthefibres.Thenaddcurryleaves,redchillipowderandotheringredientsandgrindwell.Ifkeptinairtightcontainersitcanbestoredforalongtime.

Chemicalstructure

Theleavescontainthefollowingfreeaminoacids:asparagine,glycine,serine,asparticacid,glutamicacid,theonine,alanine,proline,tyrosine,tryptophan,цaminobutyricacid,phenylalanine,leucine,isoleucine,andtracesofornithine,lysine,arginineandhistidine.Theleavesalsocontainacrystallineglucocide,koeniginandaresin.

Byanalysisofconcentratedessenceofcurryleaf,MacleodandPieris2obtainedmainlyterpenes.TheyalsofoundthatM.koenigiiproducedlessthan4%ofothercomponentswitheightmonoterpenehydrocarbons(Ca16%)andseventeensesquiterpenehydrocarbons(Ca80%).Accordingtothemthemostimportant

constituentsofM.koenigiiareβ-caryophyllene,β-gurjunene,β-elemene,β-phellandreneandβ-thujene.

Bhattacharyaetal.3reportedacarbazolealkaloid-isomurrayazolinefromM.koenigii

withastructureof9a,10,11,12,13,13a-hexahydro-5,9,9,12tetramethyl-1,12-epoxy-9H-indolo(3,2,1-de)phenanthridine(C23H27NO2).Alkaloidslikemuconicine,mahanimbine,koenimbine,koenigicine,cyclomahanimbine,mahanimbidine,girinimbine,iso-mahanimbine,murrayacine,mahanine,koenine,koenigine,koenidineandscopolinwerereportedbyvariousworkers.4

FromthestemofM.koenigii,anewC23-carbazolealkaloid,mahanimbinol,wasisolated.Itisthekeyprecursorinthebiosynthesisofsome20othercarbazolealkaloids.Bhattacharyaetal.5identifiedtwocarbazolealkaloidsnamely2-methoxycarbazole-3-methylcarboxylateand1-hydroxy-3-methylcarbazolefromthestembarkextractofM.koenigii.Fromthestembark,alkaloidslikemahanimbinol,mukonal,murrayanine,murrayacinineandmurrayazolidinewereisolatedandcharacterisedbyvariousworkers.4Thefruitisedible.Ityields0.76%ofayellowvolatileoilwithneroli-likeodourandpepper-liketaste,accompaniedbyanagreeablesensationofcoolnessonthetongue.The

characteristicsoftheoilareasfollows:

specificgravity(13o) 0.872

refractiveindex(0o) 1.487

opticalrotation(0o) —27.24

boilingpoint 173–174o

Thefruitisreportedtocontainkoenigin.Ayellowclearandtransparentoilisprocuredfromtheseedswhichisknownaslimboleeoil.

Chowdhury6reportedthatleavesonhydrodistillationgave0.5%essentialoilonfreshweightbasis,havingdarkyellowcolour,spicyodourandpungentclove-liketaste.Ithasthefollowingcharacteristics:

specificgravity(25o) 0.9748

refractiveindex(25o) 1.5021

opticalrotation(25o) +4.86

saponificationvalue 5.2

saponificationvalueafteracetylation 54.6

acidvalue 3.8

solublein80%alcoholwithslightopalescenceTheconstituentsoftheoilare:

dl-2-phellandrene 4.6%

d-sabinene 9.2%

d-2-pinene 5.5%

dipentene 6.8%

d-2-terpineol 3.2%

caryophyllene 26.3%

isosafrol 4.4%

cadinene 18.2%

cadinol 12.8%

lauricacid 2.7%

palmiticacid 3.4%

OnexaminationbyGC-MStheoilcontainedaromadendrene,β-bisabolene,butylmyristrate,carvomethone,cis-caryophyllene,β-costol,citral,trans-caryophyllene,iso-caryophyllene,camphene,dehydroaromadendrene,dipentene,β-elemene,β-eudesmol,farnesol,junipene,linalylacetate,isomenthone,menthol,spathulenol,stearylalcohol,ateraldehyde,stearicacid,2-terpineol,palmiticacid,2-pineneandzingiberene.

TheessentialoilshydrodistilledfromleavesofMurrayakoenigiiwereanalysedby

GCandGC-MS.Bothessentialoilscontainedmainlymonoterpenesandoxygenatedmonoterpenes.Themainconstituentsare2-pinene(19–19.7%),sabinene(31.8–44.8%),β-pinene(4.2–4.7%),2-terpinene(1.3–4.3%),beta-phellandrene(6.5–7.9%),tauterpinene(3.9–7.1%)andterpinen-4-01(5.2–9.9%).7Madalagerietal.8reported21

differentcompoundsinthehydrodistilledessentialoiloutofwhichonlysevenwereidentified.Acommerciallyimportantodouriferouscompoundβ-caryophylleneisamongthem.

Production

Theleavesretaintheirflavourevenafterdryingandhencethesearemarketedbothinfreshanddriedforms.Thereisnotmuchlossofvolatileoilduringdryingeitherinsun/shadeorincrossflowdryer.Ovendryingat50oCisrecommendedasthebesttechnologyforconversionoffreshleavesintodrypowder.8Highertemperaturesduringdryingdeterioratedpowderquality.

Freshleavesonsteamdistillationunderpressure(90lb/in2)yield2.6%ofavolatileoil(curryleafoil).AccordingtoMadalagerietal.8hydrodistillationoffreshleavesat70Cisacheapandnon-cumbersomemethodofextractionofessentialoil.Leafmaturityinfluencedoilcomposition,theyoungestleavestestedbeingthebest.Anextendedperiodofextractioncausedloss/decreaseincertaincomponentswhiletherewasgain/increaseinothercomponents.

Functionalproperties

Onanalysistheleavescontainthefollowingnutrients:

moisture 66.3%

protein 6.1%

fat(etherextract) 1.0%

carbohydrate 18.7%

fibre 6.4%

mineralmatter 4.2%

calcium 810mg/100gofedibleportion

phosphorus 600mg/100gofedibleportion

iron 3.1mg/100gofedibleportion

carotene(asvitaminA) 12600IU/100g

nicotinicacid 2.3mg/100g

vitaminC 4mg/100g

thiamineandriboflavin absent

TheleavesareafairsourceofvitaminA.Theyarealsoarichsourceofcalcium,butduetothepresenceofoxalicacidinhighconcentration(totaloxalates,1.35%;solubleoxalates,1.15%),itsnutritionalavailabilityisaffected.

Curryleafisusedintraditionalmedicine,forexampleayurvedicandunanimedicine.9–11Theplantiscreditedwithtonic,stomachicandcarminativeproperties.Theundilutedessentialoilexhibitedstrongantibacterialandantifungalactivitywhentestedonmicroorganisms.12Eventhecrudeleafextractsofcurryleafplantarereportedtopossessantibacterialactivity.13

Curryleafhasapotentialroleinthetreatmentofdiabetes.Hypoglycemicactiononcarbohydratemetabolismwasreportedinratsfedwithcurryleaves.14Hepaticglycogenandglycogenesis,asevidentfromtheincreasedactivityofglycogensynthetase,wereincreasedandglycogenolysisandgluconeogenesisweredecreasedasevidentfromthedecreasedactivityofglycogenphosphorylaseandgluconeogenicenzymes.

Curryleafisfoundtoexertantioxidantpropertiesinratsfedahighfatdiet.15Therewerelowerlevelsofhydroperoxides,conjugateddienesandfreefattyacidsintheliverandheartofratssupplementedwithcurryleavescomparedtoratsfedonthehighfatdietalone.Activitiesofsuperoxidedismutase,catalaseandglutathionetransferasewereincreasedintheheartandliverofratssupplementedwithcurryleaves.Activitiesofglutathionereductase,glutathioneperoxidaseandglucose-6-phosphatedehydrogenasewerealsoincreasedintheliverandtheconcentrationofglutathionewasdecreased.Thussupplementingahighfatdietwith10%curryleafcanpreventtheformationoffreeradicalsandmaintainthetissuesatnormallevels.

PatelandRajorhia16reportedthatgheesamplestreatedwith1%curryleavesduringclarificationshowedhigherresistancetooxidationandhighersensoryscoresthanthosetreatedwithamixtureofBHT(butylatedhydroxytoluene)+BHA(butylatedhydroxyanisole),duetothepresenceofnaturally-occurringantioxidants.Thecurryleavesat1%concentrationcouldbeusedinsteadofBHTandBHAforextendingtheshelf-lifeofghee.

References

COUNCILOFSCIENTIFICANDINDUSTRIALRESEARCH,TheWealthofIndia,NewDelhi,CSIR,19626446–8.

MACLOEDAJandPIERISNM,‘AnalysisofthevolatileessentialoilsofMurrayakoenigiiandPandanuslatifolius’,Phytochemistry,198221(7)1653–7.

BHATTACHARYAL,ROYSKandCHAKROVORTYDP,‘StructureofthecarbazolalkaloidisomurrayazolinefromMurrayakoenigii’,Phytochemistry,198221(9)

2432–3.

RASTOGIRPandMEHROTRABN,CompendiumofIndianMedicinalPlantsVol.I-IV

NewDelhi,PublicationandInformationDirectorate,1993.

BHATTACHARYAP,MAITAAK,BASUKandCHOWDHURYBK,‘Carbazolalkaloidsfrom

Murrayakoenigii’,Phytochemistry,199435(4)1085–6.

CHOWDHURYAR,‘EssentialoilfromtheleavesofMurrayakoenigii’,NationalSeminarResearchandDevelopmentinAromaticPlants:Currenttrendsinbiology,uses,productionandmarketingofessentialoils,Lucknow,CentralInstituteofMedicinalandAromaticPlants,1999.

MALLAVAPURAGR,RAMESHS,SYAMASUNDARKVandCHANDRASEKHARARS,

‘CompositionofIndiancurryleafoil’,J.Ess.OilRes,199911(2)176–8.

MADALAGERIBB,MAHADEVandHIREMATHSM,‘Dehydrationmethods,oilextractionandflavourcomponentsdetectioni