Utilizationofeggshellwasteincellulaseproductionbyn

IntroductionThebioconversionofwastetousableenergyispartoftheutilizationofwaste.Thusthepossibilityofproducingausefulproductfromwasteswillgreatlyenhanceandensuresustainableeconomicdevelopmentaswellaswasteman-agementproblemsworldwide[1].Theeffectivetreatmentandutilizationofbiowastehasbeenemphasizedinoursocietyforenvironmentalandeconomicconcerns.Recently,eggshellwastesinthepoultryindustryhavebeenhighlightedbecauseofitsreclamationpotential[2].Eggshellwasteisavailableinhugequantitiesfromthefoodprocessing,eggbreaking,andhatchingindustries.About250,000tonsofeggshellwasteisproducedannuallyworldwidebythefoodprocessingindustryonly.Fresheggshellwasteisapproximately95%calciumcarbonatecrys-talsstabilizedbyaproteinmatrix[3].Uronicacid,sialicacid,alanine,andglyceinwerehighintheorganicmatterofeggshellwastecomparedtoshellmembranes[4].Mostgoodqualityeggshellwasteshellcontainsapproximately2.2gofcalciumintheformofcalciumcarbonate.Theaverageeggshellcontainabout95%ofcalciumcarbonate,0.3%phosphorus,0.3%magnesium,andtracesofsodium,potassium,Zn,Mn,Fe,andCu.Eggshellwastecomposedofcalciumcarbonate,proteinmembrane,aminoacidandcollagen[5].Mostoftheeggshellwasteiscommonlydis-posedofinlandfillswithoutanypretreatmentbecauseitistraditionallyuselessandultimatelycreatesseriousenviron-mentalproblems[3].Therefore,propertreatmentisrequiredtorecovervaluablecalciumionsfromeggshellwaste.Calcium,akeysignalingmoleculeinallorganisms,isoftensequesteredinintracellularcompartments.Infila-mentousfungiacalciumgradienthasbeenproposedtoplayakeyroleinpolargrowth.FivegeneshavebeenidentifiedinN.crassathatmayencodeorganellecalciumtransports.Pol.J.Environ.Stud.Vol.21,No.2(2012),491-497*e-mail:[e-mail]zationofEggShellWasteinCellulaseProductionbyNeurosporacrassaunderWheatBran-BasedSolidStateFermentationNitinVerma*,VivekKumar,MukeshC.BansalDepartmentofPaperTechnology,IndianInstituteofTechnology,RoorkeeSaharanpurCampus,Saharanpur,U.P,247001,IndiaReceived:15February2011Accepted:21July2011AbstractAwidevarietyofwasteresourcesareavailableonourplanet.Eggshellwasteisavailableinhugequan-titiesfromthefoodprocessing,eggbreaking,andthehatchingindustries.CalciumplaysavitalroleinNeurosporacrassahyphalgrowth.Batchexperimentshavebeenperformedusingpurecalciumsaltaswellascalciumintheformofpretreatedeggshellwasteinconcentrationsof0.4,0.8,and1.2g/l,underwheatbran-basedsolidstatefermentationbyNeurosporacrassaat30ºCwithinitialpH6.0.Thepresentpaperdescribestheutilityofwheatbranandeggshellwasteincellulaseproduction.Theutilizationofeconomicallycheapandabundantlyavailableeggshellwasteforcellulaseproductioncouldbeanovelandvaluableapproachinsolidwastemanagement.Keywords:calcium,cellulase,eggshellwaste,Neurosporacrassa,wastemanagementCalciumistransportedintothevacuolebyNCA-2andNCA-3(P-typeATPase)andCAX(aCa++/H+exchanger),whereasinthegolgiitistransportedthroughPMR(aP-typeATPase),thusindicatingthatthevacuoleisamajorstoragesiteforcalcium[6].Inthetiphighcytoplasmiccal-ciumgradienthasbeenidentifyingasarequirementforhyphalgrowthintheNeurosporacrassa.Thecalciumcon-centration-dependentgrowthmayrelatedirectlytothebio-chemicalfunctionofcalciuminhyphalextensionsuchasvesiclefusionandenzymeactivationduringcellularexpan-sion.TheinitiationoftipgrowthmayrelyuponrandomCa++motion,causingalocalizedregionofelevatedcalcium[7,8].Wheatisoneofthecerealsusedextensivelyinthemanypartsoftheworldforpreparationofbreadandmanybakeryproducts[9].Industrialwheatbranusuallyaccountsfor14-19%ofthegrainandcomprisestheoutercoverings,thealeuronelayerandtheremnantsofthestarchyendosperm.Itconsistsmainlyofstarch,arabinoxylans,cellulose,β-glu-can,proteinandlignin,andhasthepotentialtoserveaslow-costfeedstocktoincreasetheproductionofcommodityproducts[10].Branisparticularlyrichindietaryfibersandcontainssignificantquantitiesofstarch,proteinsandvita-minanddietaryfibers[5].Wheatbranisagoodsourceofnitrogenduetothepresenceofproteincontent;itisalsoagoodsourceofhemicellulose,asawholeitisagoodinduc-erofthecellulolyticenzymesystem[11].Wheatbranistheouter~15%ofthewheatseedandiscomposedpredomi-nantlyofnonstarchcarbohydrates(~58%),starch(~19%),andcrudeprotein(~18%).Innon-starchcarbohydrates~25%ofcellulosepresent.Thehighamountofproteinpre-sentinthewheatbranmayalsoreducethecellulasebiosyn-thesisbutthesolubleoligosaccharides,starch,andcellulosepresentinthewheatbransignificantlyimpactcellulasepro-duction[12].Thelignocellulosicbiomass,especiallyagri-culturalwaste,isknowntobeanexcellentcarbonsourceformicrobialenzymeproduction.Cellulaseproductionfromlignocellulosicwastematerialscontainingwheatstraw:wheatbran(9:1)wasinvestigatedbyJecuandreportedendoglucanaseactivity14.80IU/mlin96hr[13].Courietal.investigatedthehydrolyticenzymes(polygalacturonase,cellulase,xylanase,andprotease)insolidstatefermentationusingwheatbranassolidsubstrate[14].Thepresentpaperrepresentsaneconomicaltreatmentprocesstorecoveruse-fulbioproductsfromwheatbranandeggshellwasteandtheirutilizationinthecellulaseproductionprocessmakestheprocesscosteffectiveandenvir