生物表面活性劑課件

生物表面活性劑生物表面活性劑Introduction

Biosurfactants(amphiphiliccompounds)(synthesizedbymicroorganisms)hydrophobic(nonpolar)hydrophilic(polar)thatconferabilitytoaccumulatebetweenfluidphasessuchasoil/waterorair/water,reducingthesurfaceandinterfacialtensionsandformingemulsions.household、industryandagriculturemono-,oligo-orpolysaccharides(多糖）,peptides（縮氨酸）orproteinssaturated,unsaturatedandhydroxylatedfattyacidsorfattyalcoholsIntroductionBiosurfactant生物表面活性劑課件生物表面活性劑課件生物表面活性劑課件生物表面活性劑課件生物表面活性劑課件生物表面活性劑課件PropertiesSurfaceandinterfaceactivitybiodegradability(bioremediation).emulsifying

anddemulsifyingabilityantimicrobialactivityPropertiesSurfaceandinterfacSurfaceandinterfaceactivity

Ingeneral,biosurfactantsaremoreeffectiveandefficientandtheirCMC(criticalmicelleconcentration)isabout10-40timeslowerthanchemicalsurfactants,i.e.,lesssurfactantisnecessarytogetamaximaldecreaseonST.

Agoodsurfactantcanlowersurfacetension(ST)ofwaterfrom72to35mN/mandtheinterfacialtension(IT)water/hexadecane（十六烷）from40to1mN/m.SurfaceandinterfaceactivityThebiosurfactantsaccumulateattheinterfacebetweentwoimmisciblefluidsorbetweenafluidandasolid..(figure1)Byreducingsurface(liquid-air)andinterfacial(liquid-liquid)tensiontheyreducetherepulsiveforcesbetweentwodissimilarphasesandallowthesetwophasestomixandinteractmoreeasilyThebiosurfactantsaccumulateBiosurfactantactivitiesdependontheconcentrationofthesurface-activecompoundsuntilthecriticalmicelleconcentration(CMC)isobtained.AtconcentrationsabovetheCMC,biosurfactantmoleculesassociatetoformmicelles,bilayersandvesicles(Figure2).TheCMCiscommonlyusedtomeasuretheefficiencyofsurfactant.EfficientbiosurfactantshavealowCMC,whichmeansthatlessbiosurfactantisrequiredtodecreasethesurfacetension.Biosurfactantactivitiesdepe

Thebiosurfactanteffectivenessisdeterminedbymeasuringitsabilitytochangesurfaceandinterfacialtensions,stabilizationofemulsionsandbystudyingitshydrophilic-lipophilicbalance(HLB).EmulsifierswithlowHLBarelipophilicandstabilizewater-in-oilemulsification,whereasemulsifierswithhighHLBhavetheoppositeeffectandconferbetterwatersolubility

Lowtoxicity

Forexample:AbiosurfactantfromP.aeruginosa（綠膿假單胞菌）（wascomparedwithasyntheticsurfactant(MarlonA-350)widelyusedinindustryintermsoftoxicityandmutagenicproperties.Bothassaysindicatedthehighertoxicityandmutageniceffectofthechemical-derivedsurfactantwhereasbiosurfactantwasconsideredslightlytonon-toxicandnon-mutagenic.lowornon-toxicproductsandtherefore,appropriateforpharmaceutical,cosmeticandfooduses.LowtoxicityForexample:AEmulsionformingandemulsionbreaking

Anemulsionisaheterogeneoussystem,consistingofatleastoneimmiscibleliquidintimatelydispersedinanotherintheformofdroplets,whosediameteringeneralexceeds0.1μm.Emulsionshaveaninternalordispersedandanexternalorcontinuousphase,sotherearegenerallytwotypes:oil-in-water(o/w)orwater-in-oil(w/o)emulsions.

Suchsystemspossessaminimalstability,whichmaybeaccentuatedbyadditivessuchassurface-activeagents(surfactants).Thus,stableemulsionscanbeproducedwithalifespanofmonthsandyears.Biosurfactantsmaystabilize(emulsifiers)ordestabilize(de-emulsifiers)theemulsion.High-molecular-massbiosurfactantsareingeneralbetteremulsifiersthanlow-molecular-massbiosurfactants.EmulsionformingandemulsionAntimicrobialactivity

Asignificativereductiononthemycoflora（真菌群）presentinstoredgrainsofcorn,peanutsandcottonseedswasobservedatiturinconcentrationof50-100ppm).Inactivationofenvelopedvirussuchasherpes（皰疹）andretrovirus（逆轉(zhuǎn)錄酶病毒）wasobservedwith80mMofsurfactin（脂肽）.

Severalbiosurfactantshaveshownantimicrobialactionagainstbacteria,fungi（真菌）,algae（藻類）andviruses.

Thelipopeptideiturin（脂肽伊枯草菌素）fromB.subtilis（枯草芽孢桿菌）showedpotentantifungalactivity.

AntimicrobialactivityAProduction

Biosurfactantsdonotcompeteeconomicallywithsyntheticsurfactants.Toreduceproductioncosts,othercarbonsources,suchasoliveoil（橄欖油），milleffluent（工廠廢水）,whey（乳清）fromcheesemaking,andcassavaflourwater（木薯粉水）,usedvegetableoils,molasses（糖漿）(by-product).

Biosurfactantshavebeensynthesizedbyvariousresearchersusingdifferentmicroorganismsandcarbonsources.Thecarbonsourcesusedforbiosurfactantproductionarehydrocarbons,

carbohydrates,andvegetableoils.ProductionBiosurfactanProductionmethodsNaturalbiologicalextractmethod、Microorganismfermentationmethod、EnzymecatalyticmethodPurificationmethodsPrecipitationmethod、Extractionmethod、Superfilteringmethod、Foamseparationmethod、Adsorptionmethod、Columnchromatographymethod、Thinlayerchromatographymethod、Highperformanceliquidchromatographymethod、Liquidsurfaceadsorptionenrichmentmethod、Liquidmembraneseparationmethod.ProductionmethodsFig.2.Structureoffourdifferentrhamnolipidsproducedby

P.aeruginosa.Fig.2.Structureoffourd生物表面活性劑課件FactorsAffectingBiosurfactant

ProductionEffectofCarbonSourceonBiosurfactantsProduction

carbohydratehydrocarbonvegetableoilsFactorsAffectingBiosurfactanEffectofSupportMaterialandRelationshipwithWater

Supportmaterialforimmobilizedenzymeaffectsthe

watercontentintheproximityoftheenzymeandthe

partitioningofreactantsand/orproductsinthereaction

mixture.Sincethermalstabilityiscloselyrelatedtothe

amountofwaterinclosevicinityoftheenzymesmolecule.Theidealcarriershouldnotretainwaterthan

necessarytoreducetheriskofenzymedenaturation（變性）.

Immobilizationonhydrophilicsupportsoftenleads

toalossoflipase（脂肪酶）activityastheenzymeundergoesa

conformational（構(gòu)象）changetoaformofreducedactivity.

Thesesupportmaterialsmayalsoreducehydrophobic

substratesolubilityinhydrophilicregions,thereby

reducingthe

accessibilityofsubstratetotheactivesites.EffectofSupportMaterialandEffectofEnvironmentalFactorsonBiosurfactantsProduction

pHtemperatureagitation（攪拌）speedoxygenavailabilityRhamnolipidproductioninpseudomonassp（假單胞菌）wasitsmaximumatapHrangefrom

6to

6.5and

decreasedsharplyabovepH7.

Inaddition,surfacetensionandCMCsofabiosurfactantproduct

remainedstableoverawiderangeofpHvalues,whereasemulsificationhadanarrowerpHrange.EffectofEnvironmentalFactor

AthermophilicBacillussp（芽孢桿菌）grewandproducedbiosurfactantattemperatureabove40℃.Heattreatmentofsomebiosurfactantscausednoappreciablechangeinbiosurfactantproperties,suchastheloweringofthesurfacetensionandinterfacialtensionandtheemulsificationefficiency,allofthatremainedstableafterautoclaving（高壓滅菌）at120℃for15min.

AnincreaseinagitationspeedresultinthereductionofbiosurfactantyieldduetotheeffectofshearinNocardia（土壤絲菌屬）.Onotherhand,inyeast,biosurfactantproductionincreaseswhentheagitationandaerationratesareincreased.

Saltconcentrationalsoaffectedbiosurfactantproductiondependingonitseffectsoncellularactivity.Some

biosurfactantproducts,however,werenotaffectedby

saltconcentrationsupto10%(wt/vol),althoughslight

reductionintheCMCsweredetected.AthermophilicBacillusspamodifieddrop-collapsetechniqueforsurfactantquantitationandscreeningofbiosurfactantproducingmicroorganismsQualitativedrop-collapsetestAdropofwaterappliedtoahydrophobicsurfaceintheabsenceofsurfactantswillformabead,asshowninFig.1(A).Thebeadforms

becausethepolarwatermoleculesarerepelledfromthehydrophobicsurface.Incontrast,ifthewaterdropletcontainssurfactant,theforceorinterfacialtensionbetweenthewaterdropandthehydrophobicsurfaceisreduced,whichresultsinthespreadingofthewaterdropoverthehydrophobicsurface(Fig.1,B).Theamountofsurfactantrequiredtocausedrop-collapseisdependentontheabilityofthesurfactanttoreducesurfaceandinterfacialtension.Themorepotentthesurfactant,thesmallerthequantitythatcanbedetected.

(A)Watercontrol(nosurfactant),(B)1000mg/Lrhamnolipid.amodifieddrop-collapsetechsurfactantquantitationbythedrop-collapseQuantitativedrop-collapsemethod:(A)Watercontrol,(B)25mg/Lrhamnolipid,(C)50mg/Lrhamnolipid,(D)75mg/Lrhamnolipidand(E)100mg/Lrhamnolipid.Inthiscase,asthesurfactantconcentrationincreased,thediameterofthesampledropincreased.surfactantquantitationbytheQuantitativeresultsfortwosurfactants,rhamnolipidandSDS,arepresentedasstandardcurvesinFig.2.Alinearcorrelationwasfoundbetweentherhamnolipidconcentrationandthedropdiameter,intherangeof0to100mg/L,withanr2=of0.997(Fig.2A).ForSDS(Fig.2B),concentrationsbetween0and2400mg/Lwerelinearlycorrelatedwithdropdiameter(r2=50.989).Fig.2.Thequantitativedrop-collapsemethod.Thefigureshowstheresultsobtainedwithtwodifferentsurfactants:(A)P.aeruginosaIGB83withaCMCof27mg/Land(B)SDSwithaCMCof1845mg/L.Eachpointrepresentsthemeanandstandarddeviationoffivereplicatesfromexperimentsthatwerecarriedoutintriplicate.Quantitativeresultsfortwo

PotentialCommercial

Applications

Mostsurfactantsarechemicallysynthesized.Nevertheless,inrecentyears,muchattentionhasbeendirectedtowardbiosurfactantsduetotheirbroad-rangefunctionalpropertiesandthediversesyntheticcapabilitiesofmicrobes.Mostimportantistheirenvironmentalacceptability,becausetheyarereadilybiodegradableandhavelowertoxicitythansyntheticsurfactants.Anumberofapplicationsof

biosurfactantshavebeenenvisaged.MEOR、FoodIndustry、CosmeticIndustry、MedicinalUse、Soil

BioremediationPotentialCommercialApplicatBiosurfactantsinMicrobialEnhancedOilRecovery(MEOR)

Fig.Mechanismofenhancedoilrecoverybybiosurfactants.theoilistrappedintheporesbycapillary

pressure.

Biosurfactantsreduceinterfacialtensionbetweenoil/waterandoil/rock.Thisreducesthecapillaryforcespreventingoilfrommovingthroughrockpores.Biosurfactantscanalsobindtightlytotheoil-waterinterfaceandformemulsion.Thisstabilizesthedesorbedoilinwaterandallowsremovalofoilalongwiththeinjectionwater.

BiosurfactantsinMicrobialETheApplicationofBiosurfactantsforSoil

BioremediationThebiologicalremediationprocesscanbeperformed(i)insitu(ii)inapreparedbed(

iii)inaslurryreactorsystemInsituprocessesareusuallyaccomplishedbyadditionofmicrobialnutrientstothesoil,whichallowsconsiderablegrowthofsoilmicrobialindigenouspopulation.Thusincreasedmicrobialbiomassinthesoil.(fig1)TheApplicationofBiosurfacta生物表面活性劑課件Figure3Mechanismofbiosurfactantactivityinmetal-contaminatedsoilduetotheloweringoftheinterfacialtension.Figure3MechanismofbiosurfConclusion

Advantage:

higherbiodegradability,betterenvironmentalcompatibility,higherfoaming,highselectivityandhighspecificactivityatextremetemperature,pHandsalinity.

Therethedemandofbiosurfactantsisincreasingworldwideinrecentyears.However,biosurfactantsdonoteconomicallycompetewithchemicallysynthesizedsurfactants.That’swhythereisagreatscopeforfurtherresearchtofindamoreeconomicalproductionprocessandtechnology.ConclusionAdvantage:higherThankYouThankYou

結(jié)束語謝謝大家聆聽！??！35

結(jié)束語謝謝大家聆聽！?。?5生物表面活性劑生物表面活性劑Introduction

Biosurfactants(amphiphiliccompounds)(synthesizedbymicroorganisms)hydrophobic(nonpolar)hydrophilic(polar)thatconferabilitytoaccumulatebetweenfluidphasessuchasoil/waterorair/water,reducingthesurfaceandinterfacialtensionsandformingemulsions.household、industryandagriculturemono-,oligo-orpolysaccharides(多糖）,peptides（縮氨酸）orproteinssaturated,unsaturatedandhydroxylatedfattyacidsorfattyalcoholsIntroductionBiosurfactant生物表面活性劑課件生物表面活性劑課件生物表面活性劑課件生物表面活性劑課件生物表面活性劑課件生物表面活性劑課件PropertiesSurfaceandinterfaceactivitybiodegradability(bioremediation).emulsifying

anddemulsifyingabilityantimicrobialactivityPropertiesSurfaceandinterfacSurfaceandinterfaceactivity

Ingeneral,biosurfactantsaremoreeffectiveandefficientandtheirCMC(criticalmicelleconcentration)isabout10-40timeslowerthanchemicalsurfactants,i.e.,lesssurfactantisnecessarytogetamaximaldecreaseonST.

Agoodsurfactantcanlowersurfacetension(ST)ofwaterfrom72to35mN/mandtheinterfacialtension(IT)water/hexadecane（十六烷）from40to1mN/m.SurfaceandinterfaceactivityThebiosurfactantsaccumulateattheinterfacebetweentwoimmisciblefluidsorbetweenafluidandasolid..(figure1)Byreducingsurface(liquid-air)andinterfacial(liquid-liquid)tensiontheyreducetherepulsiveforcesbetweentwodissimilarphasesandallowthesetwophasestomixandinteractmoreeasilyThebiosurfactantsaccumulateBiosurfactantactivitiesdependontheconcentrationofthesurface-activecompoundsuntilthecriticalmicelleconcentration(CMC)isobtained.AtconcentrationsabovetheCMC,biosurfactantmoleculesassociatetoformmicelles,bilayersandvesicles(Figure2).TheCMCiscommonlyusedtomeasuretheefficiencyofsurfactant.EfficientbiosurfactantshavealowCMC,whichmeansthatlessbiosurfactantisrequiredtodecreasethesurfacetension.Biosurfactantactivitiesdepe

Thebiosurfactanteffectivenessisdeterminedbymeasuringitsabilitytochangesurfaceandinterfacialtensions,stabilizationofemulsionsandbystudyingitshydrophilic-lipophilicbalance(HLB).EmulsifierswithlowHLBarelipophilicandstabilizewater-in-oilemulsification,whereasemulsifierswithhighHLBhavetheoppositeeffectandconferbetterwatersolubility

Lowtoxicity

Forexample:AbiosurfactantfromP.aeruginosa（綠膿假單胞菌）（wascomparedwithasyntheticsurfactant(MarlonA-350)widelyusedinindustryintermsoftoxicityandmutagenicproperties.Bothassaysindicatedthehighertoxicityandmutageniceffectofthechemical-derivedsurfactantwhereasbiosurfactantwasconsideredslightlytonon-toxicandnon-mutagenic.lowornon-toxicproductsandtherefore,appropriateforpharmaceutical,cosmeticandfooduses.LowtoxicityForexample:AEmulsionformingandemulsionbreaking

Anemulsionisaheterogeneoussystem,consistingofatleastoneimmiscibleliquidintimatelydispersedinanotherintheformofdroplets,whosediameteringeneralexceeds0.1μm.Emulsionshaveaninternalordispersedandanexternalorcontinuousphase,sotherearegenerallytwotypes:oil-in-water(o/w)orwater-in-oil(w/o)emulsions.

Suchsystemspossessaminimalstability,whichmaybeaccentuatedbyadditivessuchassurface-activeagents(surfactants).Thus,stableemulsionscanbeproducedwithalifespanofmonthsandyears.Biosurfactantsmaystabilize(emulsifiers)ordestabilize(de-emulsifiers)theemulsion.High-molecular-massbiosurfactantsareingeneralbetteremulsifiersthanlow-molecular-massbiosurfactants.EmulsionformingandemulsionAntimicrobialactivity

Asignificativereductiononthemycoflora（真菌群）presentinstoredgrainsofcorn,peanutsandcottonseedswasobservedatiturinconcentrationof50-100ppm).Inactivationofenvelopedvirussuchasherpes（皰疹）andretrovirus（逆轉(zhuǎn)錄酶病毒）wasobservedwith80mMofsurfactin（脂肽）.

Severalbiosurfactantshaveshownantimicrobialactionagainstbacteria,fungi（真菌）,algae（藻類）andviruses.

Thelipopeptideiturin（脂肽伊枯草菌素）fromB.subtilis（枯草芽孢桿菌）showedpotentantifungalactivity.

AntimicrobialactivityAProduction

Biosurfactantsdonotcompeteeconomicallywithsyntheticsurfactants.Toreduceproductioncosts,othercarbonsources,suchasoliveoil（橄欖油），milleffluent（工廠廢水）,whey（乳清）fromcheesemaking,andcassavaflourwater（木薯粉水）,usedvegetableoils,molasses（糖漿）(by-product).

Biosurfactantshavebeensynthesizedbyvariousresearchersusingdifferentmicroorganismsandcarbonsources.Thecarbonsourcesusedforbiosurfactantproductionarehydrocarbons,

carbohydrates,andvegetableoils.ProductionBiosurfactanProductionmethodsNaturalbiologicalextractmethod、Microorganismfermentationmethod、EnzymecatalyticmethodPurificationmethodsPrecipitationmethod、Extractionmethod、Superfilteringmethod、Foamseparationmethod、Adsorptionmethod、Columnchromatographymethod、Thinlayerchromatographymethod、Highperformanceliquidchromatographymethod、Liquidsurfaceadsorptionenrichmentmethod、Liquidmembraneseparationmethod.ProductionmethodsFig.2.Structureoffourdifferentrhamnolipidsproducedby

P.aeruginosa.Fig.2.Structureoffourd生物表面活性劑課件FactorsAffectingBiosurfactant

ProductionEffectofCarbonSourceonBiosurfactantsProduction

carbohydratehydrocarbonvegetableoilsFactorsAffectingBiosurfactanEffectofSupportMaterialandRelationshipwithWater

Supportmaterialforimmobilizedenzymeaffectsthe

watercontentintheproximityoftheenzymeandthe

partitioningofreactantsand/orproductsinthereaction

mixture.Sincethermalstabilityiscloselyrelatedtothe

amountofwaterinclosevicinityoftheenzymesmolecule.Theidealcarriershouldnotretainwaterthan

necessarytoreducetheriskofenzymedenaturation（變性）.

Immobilizationonhydrophilicsupportsoftenleads

toalossoflipase（脂肪酶）activityastheenzymeundergoesa

conformational（構(gòu)象）changetoaformofreducedactivity.

Thesesupportmaterialsmayalsoreducehydrophobic

substratesolubilityinhydrophilicregions,thereby

reducingthe

accessibilityofsubstratetotheactivesites.EffectofSupportMaterialandEffectofEnvironmentalFactorsonBiosurfactantsProduction

pHtemperatureagitation（攪拌）speedoxygenavailabilityRhamnolipidproductioninpseudomonassp（假單胞菌）wasitsmaximumatapHrangefrom

6to

6.5and

decreasedsharplyabovepH7.

Inaddition,surfacetensionandCMCsofabiosurfactantproduct

remainedstableoverawiderangeofpHvalues,whereasemulsificationhadanarrowerpHrange.EffectofEnvironmentalFactor

AthermophilicBacillussp（芽孢桿菌）grewandproducedbiosurfactantattemperatureabove40℃.Heattreatmentofsomebiosurfactantscausednoappreciablechangeinbiosurfactantproperties,suchastheloweringofthesurfacetensionandinterfacialtensionandtheemulsificationefficiency,allofthatremainedstableafterautoclaving（高壓滅菌）at120℃for15min.

AnincreaseinagitationspeedresultinthereductionofbiosurfactantyieldduetotheeffectofshearinNocardia（土壤絲菌屬）.Onotherhand,inyeast,biosurfactantproductionincreaseswhentheagitationandaerationratesareincreased.

Saltconcentrationalsoaffectedbiosurfactantproductiondependingonitseffectsoncellularactivity.Some

biosurfactantproducts,however,werenotaffectedby

saltconcentrationsupto10%(wt/vol),althoughslight

reductionintheCMCsweredetected.AthermophilicBacillusspamodifieddrop-collapsetechniqueforsurfactantquantitationandscreeningofbiosurfactantproducingmicroorganismsQualitativedrop-collapsetestAdropofwaterappliedtoahydrophobicsurfaceintheabsenceofsurfactantswillformabead,asshowninFig.1(A).Thebeadforms

becausethepolarwatermoleculesarerepelledfromthehydrophobicsurface.Incontrast,ifthewaterdropletcontainssurfactant,theforceorinterfacialtensionbetweenthewaterdropandthehydrophobicsurfaceisreduced,whichresultsinthespreadingofthewaterdropoverthehydrophobicsurface(Fig.1,B).Theamountofsurfactantrequiredtocausedrop-collapseisdependentontheabilityofthesurfactanttoreducesurfaceandinterfacialtension.Themorepotentthesurfactant,thesmallerthequantitythatcanbedetected.

(A)Watercontrol(nosurfactant),(B)1000mg/Lrhamnolipid.amodifieddrop-collapsetechsurfactantquantitationbythedrop-collapseQuantitativedrop-collapsemethod:(A)Watercontrol,(B)25mg/Lrhamnolipid,(C)50mg/Lrhamnolipid,(D)75mg/Lrhamnolipidand(E)100mg/Lrhamnolipid.Inthiscase,asthesurfactantconcentrationincreased,thediameterofthesampledropincreased.surfactantquantitationbytheQuantitativeresultsfortwosurfactants,rhamnolipidandSDS,arepresentedasstandardcurvesinFig.2.Alinearcorrelationwasfoundbetweentherhamnolipidconcentrationandthedropdiameter,intherangeof0to100mg/L,withanr2=of0.997(Fig.2A).ForSDS(Fig.2B),concentrationsbetween0and2400mg/Lwerelinearlycorrelatedwithdropdiameter(r2=50.989).Fig.2.Thequantitativedrop-collapsemethod.Thefigureshowstheresultsobtainedwithtwodifferentsurfactants:(A)P.aeruginosaIGB83withaCMCof27mg/Land(B)SDSwithaCMCof1845mg/L.Eachpointrepresentsthemea