Severalfungipresenthightolerancetotoxicmetalsandsomeareabletotransformmetalsintometal–oxalatecomplexes.Inthisstudy,theabilityofBeauveriabassianatopro-ducecopperoxalateswasevaluated.Growthperformancewastestedonvariouscopper-containingmedia.B.bassianaprovedhighlyresistanttocopper,toleratingconcentrationsofupto20gL−1,andprecipitatingcopperoxalatesonallmediatested.Chromatographicanalysesshowedthatthisspeciesproducedoxalicacidassolemetalchelator.Theproduc-tionofmetal–oxalatescanbeusedintherestorationandconservationofarcheologicalandmodernmetalartifacts.Theproductionofcopperoxalateswasconfirmeddirectlyusingmetallicpieces(botharcheologicalandmodern).Theconversionofcorrosionproductsintocopperoxalateswasdemonstratedaswell.InordertoassesswhetherthecapabilityofB.bassianatoproducemetal–oxalatescouldbeappliedtoothermetals,ironandsilverweretestedaswell.Ironappearstobedirectlysequesteredinthewallofthefungalhyphaeformingoxalates.However,theformationofahomogeneouslayerontheobjectisnotyetoptimal.Onsilver,aco-precipitationofcopperandsilveroxalatesoccurred.Asthisgreen-ishpatinawouldnotbeacceptableonsilverobjects,silverreductionwasexploredasatarnishingremediation.Firstexperimentsshowedthetransformationofsilvernitrateintonanoparticlesofelementalsilverbyanunknownextracellularmechanism.Theproductionofcopperoxalatesisimmediatelyapplicablefortheconservationofcopper-basedartifacts.Forironandsilverthisisnotyetthecase.However,thevastabilityofB.bassianatotrans-formtoxicmetalsusingdifferentimmobilizationmechanismsseemstoofferconsiderablepossibilitiesforindustrialapplications,suchasthebioremediationofcontaminatedsoilsorthegreensynthesisofchemicals.
E. Joseph, S. Cario, A. Simon, M. Wörle, R. Mazzeo, P. Junier, et al. (2012). Protection of metal artifacts with the formation of metal–oxalates complexes by Beauveria bassiana. FRONTIERS IN MICROBIOLOGY, 2, article 270, 1-8 [10.3389/fmicb.2011.00270].
Protection of metal artifacts with the formation of metal–oxalates complexes by Beauveria bassiana
JOSEPH, EDITH MICHELLE MARYSE;MAZZEO, ROCCO;
2012
Abstract
Severalfungipresenthightolerancetotoxicmetalsandsomeareabletotransformmetalsintometal–oxalatecomplexes.Inthisstudy,theabilityofBeauveriabassianatopro-ducecopperoxalateswasevaluated.Growthperformancewastestedonvariouscopper-containingmedia.B.bassianaprovedhighlyresistanttocopper,toleratingconcentrationsofupto20gL−1,andprecipitatingcopperoxalatesonallmediatested.Chromatographicanalysesshowedthatthisspeciesproducedoxalicacidassolemetalchelator.Theproduc-tionofmetal–oxalatescanbeusedintherestorationandconservationofarcheologicalandmodernmetalartifacts.Theproductionofcopperoxalateswasconfirmeddirectlyusingmetallicpieces(botharcheologicalandmodern).Theconversionofcorrosionproductsintocopperoxalateswasdemonstratedaswell.InordertoassesswhetherthecapabilityofB.bassianatoproducemetal–oxalatescouldbeappliedtoothermetals,ironandsilverweretestedaswell.Ironappearstobedirectlysequesteredinthewallofthefungalhyphaeformingoxalates.However,theformationofahomogeneouslayerontheobjectisnotyetoptimal.Onsilver,aco-precipitationofcopperandsilveroxalatesoccurred.Asthisgreen-ishpatinawouldnotbeacceptableonsilverobjects,silverreductionwasexploredasatarnishingremediation.Firstexperimentsshowedthetransformationofsilvernitrateintonanoparticlesofelementalsilverbyanunknownextracellularmechanism.Theproductionofcopperoxalatesisimmediatelyapplicablefortheconservationofcopper-basedartifacts.Forironandsilverthisisnotyetthecase.However,thevastabilityofB.bassianatotrans-formtoxicmetalsusingdifferentimmobilizationmechanismsseemstoofferconsiderablepossibilitiesforindustrialapplications,suchasthebioremediationofcontaminatedsoilsorthegreensynthesisofchemicals.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
