TheCitricAcidtestkitisa flexibleandsimplemethodfortherapidandreliablemeasurementandanalysisofcitricacid(citrate)infoods,beveragesandothermaterials.
Grapeandwineanalysis:Oenologiststoexploitadvancedtestkits.
Charnock,S.C.&McCleary,B.V.(2005).RevuedesEnology,117,1-5.
LinktoArticle
ReadAbstract
Itiswithoutdoubtthattestingplaysapivotalrolethroughoutthewholeofthevinificationprocess.Toproducethebestpossiblequalitywineandtominimiseprocessproblemssuchas“stuck”fermentationortroublesomeinfections,itisnowrecognisedthatifpossibletestingshouldbeginpriortoharvestingofthegrapesandcontinuethroughtobottling.Traditionalmethodsofwineanalysisareoftenexpensive,timeconsuming,requireeitherelaborateequipmentorspecialistexpertiseandfrequentlylackaccuracy.However,enzymaticbio-analysisenablestheaccuratemeasurementofthevastmajorityofanalytesofinteresttothewinemaker,usingjustonepieceofapparatus,thespectrophotometer(seepreviousissueNo.116foradetailedtechnicalreview).Grapejuiceandwineareamenabletoenzymatictestingasbeingliquidstheyarehomogenous,easytomanipulate,andcangenerallybeanalysedwithoutanysamplepreparation.
Megazyme“advanced”winetestkitsgeneralcharacteristicsandvalidation.
Charnock,S.J.,McCleary,B.V.,Daverede,C.&Gallant,P.(2006).ReveuedesOenologues,120,1-5.
LinktoArticle
ReadAbstract
ManyoftheenzymatictestkitsareofficialmethodsofprestigiousorganisationssuchastheAssociationofOfficialAnalyticalChemicals(AOAC)andtheAmericanAssociationofCerealChemists(AACC)inresponsetotheinterestfromoenologists.Megazymedecidedtouseitslonghistoryofenzymaticbio-analysistomakeasignificantcontributiontothewineindustry,bythedevelopmentofarangeofadvancedenzymatictestkits.Thistaskhasnowbeensuccessfullycompletedthroughthestrategicandcomprehensiveprocessofidentifyinglimitationsofexistingenzymaticbio-analysistestkitswheretheyoccurred,andthenusingadvancedtechniques,suchasmolecularbiology(photo1),torapidlyovercomethem.Noveltestkitshavealsobeendevelopedforanalytesofemerginginteresttotheoenologist,suchasyeastavailablenitrogen(YAN;seepages2-3ofissue117article),orwherepreviouslyenzymesweresimplyeithernotavailable,orweretooexpensivetoemploy,suchasforD-mannitolanalysis.
Influenceofstarterculturesontheantioxidantactivityofkombuchabeverage.
Malbaša,R.V.,Lončar,E.S.,Vitas,J.S.&Čanadanović-Brunet,J.M.(2011).FoodChemistry,127(4),1727-1731.
LinktoArticle
ReadAbstract
Thispaperinvestigatestheinfluenceofstartercultures,obtainedfromkombuchaisolates,ontheantioxidantactivityofkombuchabeverages.Threestartercultureswereusedasfollows:(1)mixedcultureofaceticbacteriaandZygosaccharomycessp.(SC1);(2)mixedcultureofaceticbacteriaandSaccharomycescerevisiae(SC2);aswellas(3)nativelocalkombucha.Thestartercultureswereaddedtoblackandgreenteasweetenedwith7%ofsucrose.Fermentationwascarriedoutat28°Cfor10days.AntioxidantactivitytohydroxylandDPPHradicalswasmonitored.KombuchabeverageonblackteahasshownthehighestantioxidantactivitytobothtypesofradicalswithstarterSC1,whilethegreenteabeveragehasshownthehighestactivitywithnativekombucha.Themainreasonforthedifferentantioxidantactivities,besideteacomposition,wasascribedtodifferingproductionofbothvitaminCandtotalorganicacidsintheinvestigatedsystems.
Constructionandcharacterizationofthreelactatedehydrogenase-negativeEnterococcusfaecalisV583mutants.
Jönsson,M.,Saleihan,Z.,Nes,I.F.&Holo,H.(2009).AppliedandEnvironmentalMicrobiology,75(14),4901-4903.
LinktoArticle
ReadAbstract
TherolesofthetwoldhgenesofEnterococcusfaecaliswerestudiedusingknockoutmutants.Deletionofldh-1causesametabolicshiftfromhomolacticfermentationtoethanol,formate,andacetoinproduction,withahighlevelofformateproductionevenunderaerobicconditions.Ldh-2playsonlyaminorroleinlactateproduction.
Isolationoflipaseandcitricacidproducingyeastsfromagro-industrialwastewater.
Mafakher,L.,Mirbagheri,M.,Darvishi,F.,Nahvi,I.,Zarkesh-Esfahani,H.&Emtiazi,G.(2010).NewBiotechnology,27(4),337-340.
LinktoArticle
ReadAbstract
Productionofagro-industrialwastepollutantshasbecomeamajorproblemformanyindustries.However,agro-industrialwastesalsocanprovidealternativesubstratesforindustryandtheirutilizationinthismannermayhelpsolvepollutionproblems.Theaimofthisstudywastoisolateyeastsfromwastewatertreatmentplantsthatcouldbeusedtoremovepollutantssuchasglycerol,paraffinandcrudeoilfromtheagro-industrialwastewater.Inthisstudyatotalof300yeastisolateswereobtainedfromsamplesofagro-industrialwastes,andtwostrains(M1andM2)wereinvestigatedfortheirabilitytoproducevaluableproductssuchaslipaseandcitricacid.IdentificationtestsshowedthattheseisolatesbelongedtothespeciesYarrowialipolytica.TheY.lipolyticaM1andM2strainsproducedmaximumlevelsoflipase(11and8.3U/ml,respectively)onoliveoil,andhighlevelsofcitricacid(27and8g/l,respectively)oncitricacidfermentationmedium.
ComparisonofeffectsofdietarycoconutoilandanimalfatblendonlactationalperformanceofHolsteincowsfedahigh-starchdiet.
Hollmann,M.&Beede,D.K.(2012).JournalofDairyScience,95(3),1484-1499.
LinktoArticle
ReadAbstract
Dietarymedium-chainfattyacids(C8:0throughC12:0)areresearchedfortheirpotentialtoreduceentericmethaneemissionsandtoincreaseNutilizationefficiencyinruminants.Weaimedto1)comparecoconutoil(CNO;∼60%medium-chainfattyacids)withasourceoflong-chainfattyacids(animalfatblend;AFB)onlactationalresponsesinahigh-starchdietand2)determinetheeffectofdifferentdietaryconcentrationsofCNOondrymatterintake(DMI).Inexperiment1,thecontroldiet(CTRL)contained(drybasis)40%forage(71%cornsilage,andalfalfahayandhaylage),26%NDF,and35%starch.Isonitrogenoustreatmentdietscontained5.0%ofAFB(5%-AFB),CNO(5%-CNO),ora1-to-1mixtureofAFBandCNO(5%-AFB-CNO)and0.8%cornglutenmealinplaceofcorngrain.Thirty-twomultiparousdairycows(201±46dpostpartum;42.0±5.5kg/d3.5%fat-correctedmilkyield)wereadaptedtoCTRL,blockedbymilkyield,andrandomlyassignedto1of4treatmentdietsfor21dwithsamplesanddatacollectedfromd15through21.Treatment5%-CNOdecreasedDMImarkedlyandprecipitouslyandwasdiscontinuedafterd5.Inwk3,5%-AFBandespecially5%-AFB-CNOloweredtotal-tractNDFdigestedvs.CTRL(2.6vs.1.8vs.3.1kg/d,respectively),likelybecausefattreatmentsreducedDMIand5%-AFB-CNOimpairedtotal-tractNDFdigestibility.Milkfatconcentrationswere3.10%(CTRL),2.51%(5%-AFB),and1.97%(5%-AFB-CNO)andcorrelatednegativelytoconcentrationsofC18:2trans-10,cis-12inmilkfat.Additionally,5%-AFBand5%-AFB-CNOtendedtolowermilkyieldanddecreasedyieldsofsolids-correctedmilkandmilkproteincomparedwithCTRL.Fattreatmentsdecreasedmilklactoseconcentration,butincreasedmilkcitrateconcentration.Moreover,cowsfed5%-AFB-CNOproducedlesssolids-correctedmilkthandidcowsfed5%-AFB.Inexperiment2,dietssimilartoCTRLcontained2.0,3.0,or4.0%CNO.Fifteenmultiparouscows(219±42dpostpartum;42.1±7.0kgmilkyield;mean±SD)wereblockedbyDMIandrandomlyassignedto1of3treatmentdietsforan8-devaluation.DietaryconcentrationofCNOaffectedDMI,withthegreatestdepressionat4.0%CNO.Overall,dietaryCNOdepressedDMIandNDFdigestibilityofahigh-starchdietcomparedwithAFB.FeedingCNOtolactatingcowsequaltoorgreaterthan2.5%decreasedlactationalperformanceorDMI.
EnhancedproductionofcitricacidinYarrowialipolyticabyTritonX-100.
Mirbagheri,M.,Nahvi,I.,Emtiazi,G.&Darvishi,F.(2011).AppliedBiochemistryandBiotechnology,165(3),1068-1074.
LinktoArticle
ReadAbstract
Variouschemicalsurfactantscouldaffectpermeabilityofyeastcells.Inthisstudy,effectsofthesurfactantadditionuponyeastcellspermeabilityandcitricacid(CA)productionbyYarrowialipolyticastrainsDSM3286andM7wereinvestigated.TheadditionofTritonX-100increased1.4–1.8-foldofthemaximumCAquantityachievedforbothstrains,withfinalCAconcentrationsrangingbetween75–85g/lthatcorrespondtoCAconversionyieldsperunitofglucoseconsumedof~0.80–0.84g/g.ScanningelectronmicrographsofyeastcellsshowedthatthecellstreatedwithTritonX-100hadalteredcellstructureandweresmallerandnarrowercomparedwiththenon-treatedones.TheresultsshowedthatTritonX-100couldbeusedinordertoincreasetheefficiencyofCAproductionbyY.lipolyticastrains.
NaturalvariationforFe-efficiencyisassociatedwithupregulationofStrategyImechanismsandenhancedcitrateandethylenesynthesisinPisumsativumL.
Kabir,A.H.,Paltridge,N.G.,Able,A.J.,Paull,J.G.&Stangoulis,J.C.R.(2012).Planta,235(6),1409-1419.
LinktoArticle
ReadAbstract
Iron(Fe)-deficiencyisacommonabioticstressinPisumsativumL.growninmanypartsoftheworld.TheaimofthestudywastoinvestigatevariationintolerancetoFedeficiencyintwopeagenotypes,Santi(Fe-efficient)andParafield(Fe-inefficient).Fedeficiencycausedgreaterdeclinesinchlorophyllscore,leafFeconcentrationandroot–shootdevelopmentinParafieldcomparedtoSanti,suggestinggreaterFe-efficiencyinSanti.FechelatereductaseactivityandethyleneproductionwereincreasedintherootsofSantiandtoalesserextentinParafieldunderFedeficiency,whileprotonextrusionwasonlyoccurredinSanti.Moreover,expressionoftheFechelatereductasegene,FRO1,andFetransporter,RIT1wereupregulatedinFe-deficientrootsofSanti.ExpressionofHA1(protonextrusion)wasalsosignificantlyhigherinSantiwhencomparedtoParafieldgrowninFe-deficientconditions.Furthermore,theapplicationoftheethylenebiosynthesisinhibitor,1-aminoisobutyricacidreducedtheFechelatereductaseactivity,supportingadirectroleforethyleneinitsinduction.AsignificantincreaseinrootcitratewasonlyobservedinSantiunderFedeficiencyindicatingaroleforcitrateintheFe-efficiencymechanism.Takentogether,ourphysiologicalandmoleculardataindicatethatgenotypicvariationintolerancetoFedeficiencyinSantiandParafieldplantsisaresultofvariationinanumberofStrategyImechanismsandalsosuggestadirectroleforethyleneinFereductaseactivity.Thepeacultivar,SantiprovidesanewsourceofFe-efficiencythatcanbeexploitedtobreedmoreFe-efficientpeas.
Apaf-1-deficientfogmousecellapoptosisinvolveshypo-polarizationofthemitochondrialinnermembrane,ATPdepletionandcitrateaccumulation.
Katoh,I.,Sato,S.,Fukunishi,N.,Yoshida,H.,Imai,T.&Kurata,S.I.(2008).Cellresearch,18(12),1210-1219.
LinktoArticle
ReadAbstract
Toexplorehowtheintrinsicapoptosispathwayiscontrolledinthespontaneousfog(forebrainovergrowth)mutantmicewithanApaf1splicingdeficiency,weexaminedspleenandbonemarrowcellsfromApaf1+/+(+/+)andApaf1fog/fog(fog/fog)miceforinitiatorcaspase-9activationbycellularstresses.Whenthemitochondrialinnermembranepotential(Δψm)wasdisruptedbystaurosporine,+/+cellsbutnotfog/fogcellsactivatedcaspase-9tocauseapoptosis,indicatingthelackofapoptosome(apoptosisproteaseactivatingfactor1(Apaf-1)/cytochromec/(d)ATP/procaspase-9)functioninfog/fogcells.However,whenamarginal(~20%)decreaseinΔψmwascausedbyhydrogenperoxide(0.1mM),peroxynitritedonor3-morpholinosydnonimine(0.1mM)andUV-Cirradiation(20J/m2),both+/+andfog/fogcellstriggeredprocaspase-9auto-processinganditsdownstreamcascadeactivation.Supportingourpreviousresults,procaspase-9pre-existinginthemitochondriainduceditsauto-processingbeforethecytosoliccaspaseactivationregardlessofthegenotypes.CellularATPconcentrationsignificantlydecreasedunderthehypoactiveΔψmcondition.Furthermore,wedetectedaccumulationofcitrate,akosmotropeknowntofacilitateprocaspase-9dimerization,probablyduetoafeedbackcontroloftheKrebscyclebytheelectrontransfersystem.Thus,mitochondrialinsitucaspase-9activationmaybecausedbythemajormetabolicreactionsinresponsetophysiologicalstresses,whichmayrepresentamodeofApaf-1-independentapoptosishypothesizedfromrecentgeneticstudies.
Relationshipsbetweenacceptanceofsourtasteandfruitintakesin18-month-oldinfants.
Blossfeld,I.,Collins,A.,Boland,S.,Baixauli,R.,Kiely,M.&Delahunty,C.(2007).BritishJournalofNutrition,98(05),1084-1091.
LinktoArticle
ReadAbstract
Thepresentstudyexaminedwhetherinfantsshowanacceptanceforextremesourtastesandwhetheracceptanceofsourtasteisrelatedtoinfantsfruitintake.Fruitintakeoffifty-threeinfantsat6,12and18monthswasassessedusing3dfoodrecords.Souracceptanceoftheseinfantswasstudiedat18•1(sd1•5)months.Acceptanceforfoursolutionsdifferingincitricacidconcentrations(0•00m,0•013m,0•029mand0•065m)wasmeasuredbyallowinginfantsadlibitumingestionofeachsolutionoverbrieftimeperiods.Thebasesolutiontowhichcitricacidwasaddedwasblackcurrantsquashdilutedinwater.Infantsrelativeintakeofeachsolutionwasusedasameasureofsouracceptance.At18months,twelveinfantsreadilyacceptedthetwohighestcitricacidconcentrations,whereastheremaininginfantsrejectedthese.Infantswhoacceptedthemostsoursolutionshadasignificantlyhigherfruitintake(P=0•025)andahigherfruitvariety(P=0•015)at18monthsthantheinfantswhorejectedthehighlysourtaste.Furthermore,infantswhoacceptedthemostsoursolutionsconsumedfruitsmorefrequentlyat18months(Χ25•1;P=0•024).Infantswhoacceptedthesourestsolutionsalsohadahigherfruitintakeat6months,andasignificantlyhigherincreaseintheirfruitintakefrom12to18months.Thisisthefirstscientificstudythatdemonstratestheacceptanceofsourtastesinsomeinfantsattheageof18months.Furthermore,thepresentresultssuggestarelationshipbetweenacceptanceofsourtastesandinfantsfruitintakes.
TaxonomiccharacterizationandpotentialbiotechnologicalapplicationsofYarrowialipolyticaisolatedfrommeatandmeatproducts.
Mirbagheri,M.,Nahvi,I.,Emtiazi,G.,Mafakher,L.&Darvishi,F.(2012).JundishapurJournalofMicrobiology,5(1),346-351.
LinktoArticle
ReadAbstract
Background:SomespeciesofyeastsuchasYarrowialipolyticaproducecitricacid,lipases,single-celloil,etc.Y.lipolyticacandegraderenewable,low-costsubstratestoproduceorganicacidslikecitricacid,moreefficientlythanAspergillusniger,andresultinhigherproductyieldandlesserwasteproductionandtoxicity.Objectives:Theaimofthisstudywastoisolateyeaststrainswithpotentialforuseinbiotechnologicalapplicationssuchasproductionofcitricacidandlipase.MaterialsandMethods:Foryeaststrainscreening,weisolated179yeaststrainsfrommeatandmeatproductsthatwerepreparedattheRAKandPegahfactoriesinIsfahan,Iran.Differentmediawereusedforscreeningofyeastcoloniesandforanalysesofcitricacidandlipaseproduction;theproductionofthesemetaboliteswasassayedovertime.Results:Oneoftheyeaststrainsisolatedfrompoultryproduced55.5g/Lofcitricacidand12.3U/mLoflipase.BiochemicalandmoleculartestsshowedthatthisstrainbelongedtothespeciesY.lipolytica.MolecularidentificationwasconfirmedbyDNAsequencing,andthestrainwasnamedY.lipolyticaM7(GenBankaccessionnumber,HM011048).Conclusions:Theresultsofthisstudysuggestthatmeatanditsproducts,especiallypoultryproducts,aresuitablesourcesforisolationofyeaststrainsthatproducetwobiotechnologicallyvaluableproducts-citricacidandlipase.TheyeaststrainY.lipolyticaM7canbeusedforcitricacidproductioninbioreactor.
Geneticmappingofa7RAltoleranceQTLintriticale(xTriticosecaleWittmack).
Niedziela,A.,Bednarek,P.T.,Labudda,M.,Mańkowski,D.R.&Anioł,A.(2014).JournalofAppliedGenetics,55(1),1-14.
LinktoArticle
ReadAbstract
Triticale(x
TriticosecaleWittmack)isarelativelynewcerealcrop.InPoland,triticaleisgrownon12%ofarableland(http://www.stat.gov.pl).Thereisanincreasinginterestinitscultivationduetoloweredproductioncostsandincreasedadaptationtoadverseenvironmentalconditions.However,ithasaninsufficienttolerancetothepresenceofaluminumions(Al
3+)inthesoil.Thenumberofgenescontrollingaluminumtoleranceintriticaleandtheirchromosomallocationisnotknown.TwoF2mappingbiparentalpopulations(MP1andMP15)segregatingforaluminum(Al)toleranceweretestedwithAFLP,SSR,DArT,andspecificPCR
Markers.Geneticmappingenabledtheconstructionoflinkagegroupsrepresentingchromosomes7R,5Rand2B.Obtainedlinkagegroupswerecommonforbothmappingpopulationsandmostlyincludedthesamemarkers.Compositeintervalmapping(CIM)allowedidentificationofasingleQTLthatmappedtothe7Rchromosomeandexplained25%(MP1)and36%(MP15)ofphenotypicvariation.TheB1,B26andX
scm150markerswere0.04cMand0.02cMfromthemaximumoftheLODfunctionintheMP1andMP15,respectivelyandwerehighlyassociatedwithaluminumtoleranceasindicatedbyKruskal–Wallisnonparametrictest.Moreover,themolecularmarkersB1,B26,X
rems1162and
Xscm92,previouslyassociatedwiththe
Alt4locusthatencodedanaluminum-activatedmalatetransporter(
ScALMT1)thatwasinvolvedinAltoleranceinrye(
Secalecereale)alsomappedwithinQTL.BiochemicalanalysisofplantsrepresentedMP1andMP15mappingpopulationsconfirmedthattheQTLlocatedon7RchromosomeinbothmappingpopulationsisresponsibleforAltolerance.
CompromisedLactobacillushelveticusstarteractivityinthepresenceoffacultativeheterofermentativeLactobacilluscaseiDPC6987resultsinatypicaleyeformationinSwiss-typecheese.
O’Sullivan,D.J.,McSweeney,P.L.H.,Cotter,P.D.,Giblin,L.&Sheehan,J.J.(2016).Journalofdairyscience,99(4),2625-2640.
LinktoArticle
ReadAbstract
Nonstarterlacticacidbacteriaarecommonlyimplicatedinundesirablegasformationinseveralvarieties,includingCheddar,Dutch-,andSwiss-typecheeses,primarilyduetotheirabilitytofermentawidevarietyofsubstrates.Thiseffectcanbemagnifiedduetofactorsthatdetrimentallyaffectthecompositionoractivityofstarterbacteria,resultinginthepresenceofgreaterthannormalamountsoffermentablecarbohydratesandcitrate.TheobjectiveofthisstudywastodeterminethepotentialforafacultativelyheterofermentativeLactobacillus(LactobacilluscaseiDPC6987)isolatedfromacheeseplantenvironmenttopromotegasdefectsintheeventofcompromisedstarteractivity.ASwiss-typecheesewasmanufactured,atpilotscaleandintriplicate,containingatypicalstarterculture(StreptococcusthermophilusandLactobacillushelveticus)togetherwithpropionicacidbacteria.Lactobacillushelveticuspopulationswereomittedincertainvatstomimicstarterfailure.LactobacilluscaseiDPC6987wasaddedtoeachexperimentalvatat4logcfu/g.CheesecompositionalanalysisandX-raycomputedtomographyrevealedthatthefailureofstarterbacteria,inthiscaseL.helveticus,coupledwiththepresenceofafaculativelyheterofermentativeLactobacillus(L.casei)ledtoexcessiveeyeformationduringripening.Theavailabilityofexcessamountsoflactose,galactose,andcitrateduringtheinitialripeningstageslikelyprovidedtheheterofermentativeL.caseiwithsufficientsubstratesforgasformation.TheaccrualofthesefermentablesubstrateswasnotableincheeseslackingtheL.helveticusstarterpopulation.Theresultsofthisstudyarecommerciallyrelevant,astheydemonstratetheimportanceofviabilityofstarterpopulationsandthecontrolofspecificnonstarterlacticacidbacteriatoensureappropriateeyeformationinSwiss-typecheese.
Chemicalcompositionandinvitroantimicrobialandcytotoxicactivitiesofplum(PrunusdomesticaL.)wine.
Miljić,U.,Puškaš,V.,Velićanski,A.,Mašković,P.,Cvetković,D.&Vujić,J.(2016).JournaloftheInstituteofBrewing,122(2),342-349.
LinktoArticle
ReadAbstract
Amoderateintakeofwineisassociatedwithapositiveimpactonhumanhealthowingtotheeffectsofimportantbiologicallyactivecomponentspresentinthewineinlargeamounts.Theaimofthisstudywastoexaminethechemicalcompositionandtoassessantimicrobialandcytotoxicactivitiesoffruitwinesproducedfromthreeplumvarieties(Čačanskarana,ČačanskalepoticaandPožegača)commonlygrowninSerbiaasanapproachtoassessthequalityandacceptabilityofthesewinesasafunctionalfood.Furthermore,theactivityofaseriesofcontrolsampleswasassessedinordertodeterminecomponentsfromthewinethatareresponsibleforitsfunctionalproperties.Theplumwinesproducedshowedconsiderableantimicrobialactivityagainstsixbacterialandtwoyeaststrainsusedinthisstudy.Inadditiontoantimicrobialactivity,theplumwinesshowedasignificantcytotoxiceffect(IC50 < 50 µg mL-1)onthegrowthofthreetestedcancercelllines(Hep2c,RDandL2OB).Regardingthedeterminedactivities,Čačanskaranaplumwineachievedthebestresults.Theresultsindicatedthattheantimicrobialactivityoftheplumwineswas,inlargepart,basedontheeffectsofthetotalacidsandthepHvalue,whilethecontributionofethanolandthecontentofthephenoliccompoundswerenotsignificant.Similarconclusionsweredrawnregardingthecytotoxicactivityofthisfruitwine.Theresultscanbeseenasacontributiontotheglobalacceptanceoffruitwinesasafunctionalfood,withtheaccentplacedonmoderateconsumption.Animportantadvantageoffruitwines(inparticularplumwine),comparedwithtraditionalgrapewine,istheirloweralcoholcontent.
