Study on the biodeterioration of alkyd ah resin used as a binding medium for modern paintings by Pyrolysis-Gas Chromatography-mass spectrometry and FTIR spectroscopy

ARCHÉ. PUBLICACIÓN DEL INSTITUTO UNIVERSITARIO DE RESTAURACIÓN DEL PATRIMONIO DE LA UPV - Núm. 3 - 2008 191 ABSTRACT: E alua ion o he al e a ion p oduced by mic obiological a ack on alkyd esins has been ca ied ou by FTIR spec- oscopy and Py olysis-Gas Ch oma og aphy/Mass Spec ome y (Py-GC/MS). The la e included he online de i a isa ion o alkyd esins using hexame hyldisilazane du ing py olysis. Specimens consis ing o hin ilms o esins o med on glass slides we e used. Analyses pe o med on he specimens in which di e en gene a o bac e ia and ungi we e inocula ed and allowed o g ow, indica e ha he a ack o mic oo ganisms encou ages he scissioning o he polyme ic esins and he appea ance o sho -chain a y acids. IR bands asc ibed o ca boxylic acids appea ing in samples om inocula ed specimens, as well as an inc ease in he con en o sho -chain a y acids de ec ed by Py-GC/MS om specimens inocula ed wi h ungi, con i m hese esul s and sugges ha he e ec s o me abolic p ocesses in hese mic oo ganisms a e mo e signi ican han hose o bac e ia. KEYWORDS: alkyd esin, binding media, Py-GC-MS, biode e io a ion, FTIR spec oscopy INTRODUCTION Alkyd esins employed as a pain medium began in he 1930s. They we e also widely used as household pain s and, mo e a ely, as a is s’ pain s un il he Second Wo ld Wa when ac ylic esins we e in oduced in o he A ’s ield. Alkyd esin can be conside ed oil-modi ied polyes e s, o med by combining a polyhyd ic alcohol and a polybasic acid. Glyce ol, ime hylol p opane and pen ae y h i ol, e hylenglycol, hexane iol and 1,6-hexanediol a e he mo e commonly used polyhyd ic alcohols, whe eas o o-ph alic, isoph alic, e eph alic, a a ic, ci ic, succinic, hyd oxysuccinic, maleic, uma ic, adipic and sebacic a e equen ly used as polybasic acids. Rega ding pain s, a co-polyme isa ion wi h a mix u e o a y acids de i ed om na u al oils (linseed, sa lowe , soya, all, ung o cas o oil) is ca ied ou so ha he unsa u a ed a y mono acids included in hei composi ion a o d pain app op ia e d ying p ope ies. O he componen s can be added o he o mula ion o an alkyd pain in o de o imp o e i s p ope ies. S y ene, inyl oluene, osin alone o combined wi h pheno ic, benzoic acid, silicone o wi h an ac ylic o u e hane addi ion inc eases ha dness o chemical and wa e esis ance, and also cu s down on d ying imes. Modi ica ions wi h polyamide enhance he hixo opic p ope ies o alkyd pain . The cha ac e isa ion o he s abili y o syn he ic esins used in Fine A s has p o ec i e and binding media which ha e caugh he a en ion o scien is s in ol ed in he i age conse a ion gi en hei Ma ía Te esa Doménech-Ca bó1, Gio ana Bi ossi1, Juana de la C uz-Cañiza es1, Fe nando Bolí a -Galiano2, Ma ia del Ma López-Mi as2, Julio Rome o-Nogue a2, Inés Ma ín-Sánchez3, José Vicen e Gimeno-Adelan ado4 and An onio Doménech-Ca bó Ins i u o Uni e si a io de Res au ación del Pa imonio de la Uni e si a Poli écnica de València 1 Labo a o io de análisis ísico-químico y medioambien al de ob as de a e 2 Depa amen o de Pin u a, Facul ad de Bellas A es, Uni e sidad de G anada 3 Depa amen o de Mic obiología, Facul ad de Ciencias, Uni e sidad de G anada 4 Depa amen o de Química Analí ica, Facul ad de Química, Uni e sidad de Valencia CORRESPONDING AUTHOR: Ma ía Te esa Doménech-Ca bó, [email p o ec ed].es highe deg ee o eac i i y i compa ed o ha o ino ganic ma e ials also p esen in a objec s. This p ocess is equen ly ex ended owing o he common p ac ice o con empo a y pain e s o no applying a p o ec i e coa ing o a nish on pain laye s so hey a e di ec ly exposed o en i onmen al agen s. Some wo ks in he li e a u e a e speci ically dedica ed o he s udy o he biode e io a ion o alkyd esins used in a and a conse a ion (Cappi elli e al. 2004: 399; Abdel-Ka eem O, 2000: 1; Cappi elli e al. 2004: 399; Cappi elli e al. 2005: 49). The mic obiological agen s we e, in his case, Al e na ia enuissima, Aspe gillus e sicolo , Aspe gillus nige , Aspe gillus la us, Aspe gillus nidulans, Aspe gillius e eus, Penicillium aspe um, Penicillium uniculosum, Chae onium globosum, Gliocladium i ens, Au eobasidium pullulans, Penicillium pinophilum, and T ichode ma i ide. I should be no ed ha no wo k has been ound epo ing he s udy o biode e io a ion o alkyd esins due o bac e ia a ack. None heless, he signi ican ole o he addi i es included in esin-based p oduc s as he m ai n c a bon s ou ce o he a ac k ing m ic o o ga n isms ha s been highligh ed (Cappi elli e al. (2004): 399). In his case, he polyme was a acked as a esul o he non-speci ic enzymes gene a ed by he biomass p oduced unde he so-called “co-me abolic condi ions”. A a ie y o ins umen al echniques has been p oposed o iden i ying biode e io a ion p oduc s o syn he ic polyme s, among which we ci e he “S anda d P ac ice o De e mining Resis ance STUDY ON THE BIODETERIORATION OF ALKYD AH RESIN USED AS A BINDING MEDIUM FOR MODERN PAINTINGS BY PYROLYSIS-GAS CHROMATOGRAPHY-MASS SPECTROMETRY AND FTIR SPECTROSCOPY 192 ARCHÉ. PUBLICACIÓN DEL INSTITUTO UNIVERSITARIO DE RESTAURACIÓN DEL PATRIMONIO DE LA UPV - Núm. 3 - 2008 Ma ía Te esa Doménech-Ca bó, Gio ana Bi ossi, Juana de la C uz-Cañiza es, Fe nando Bolí a -Galiano, Ma ia del Ma López-Mi as, Julio Rome o-Nogue a, Inés Ma ín-Sánchez, José Vicen e Gimeno-Adelan ado and An onio Doménech-Ca bó 2.2. Ins umen a ion and p ocedu es Ins umen a ion Expe imen s we e ca ied ou wi h an in eg a ed sys em composed o a CDS Py op obe 1000 hea ed ilamen py olyse (Analy ical Inc., New Yo k, USA), and an Agilen 6890N gas ch oma og aph (Agilen Technologies, Palo Al o, Ca., USA) coupled o an Agilen 5973N mass spec ome e (Agilen Technologies) and equipped wi h a py olysis injec ion sys em. A capilla y column HP-5MS (5% phenyl-95% me hylpolysiloxane, 30 m x 0.25 mm I.D., 0.25 Pm ilm hickness, Agilen Technologies) was used o adequa ely sepa a e componen s. Py olysis was pe o med a 650ºC o 10 s. using a p ecalib a ed P coil ype py olyze (CDS py op obe). The py olyse in e ace and he inle we e se a 250ºC. Samples we e injec ed in o he spli mode (spli a io 1:80). The ch oma og aphic condi ions we e as ollows: ini ial empe a u e o 50ºC inc eased by 5ºC. min-1 up o 100ºC, and inc eased by 15ºC.min-1 up o 295ºC, held o 2 min. The helium gas low was se a 1.2 ml.min-1. The elec onic p essu e con ol was se o he cons an low mode wi h acuum compensa ion. Ions we e gene a ed by elec on ionisa ion (70eV ) i n he ion isa ion chambe o he mass spec ome e . The mass spec ome e was scanned om m/z 20 o m/z 800 wi h a cycle ime o one second. The Agilen Chems a ion so wa e G1701CA MSD was used o GC-MS con ol and mass spec a e alua ion. EI mass spec a we e acqui ed in he o al ion moni o ing mode. The empe a u es o bo h he in e ace and sou ce we e 280ºC and 150ºC, espec i ely. NIST and Wiley Lib a y o Mass Spec a we e used o iden i ying compounds. The whi e laye was cha ac e ised by means o a Ve ex® 70 in a ed spec oscope wi h a coa ed and he mally s abilised de ec o by FR-DGTS ( as eco e y deu e a ed iglycine sulpha e). Numbe o scans: 32, esolu ion: 4 cm-1. The analysis so wa e used was OPUS®. o Syn he ic Polyme ic Ma e ials o Fungi” (ASTM G21-96(2002)) and he “S anda d P ac ice o De e mining Algal Resis ance o Plas ic Films” (ASTM G29-96(2002)) (Cappi elli e al. (2004): 399, Cappi elli e al. 2005: 49). These me hods a e ex ensi ely used o his pu pose and a e based on he measu emen o he isual appea ance, op ical and elec onic mic oscopic obse a ion, and also on he measu emen o mechanical and elec ical p ope ies. In he conse a ion o a wo ks ield, a numbe o analy ical me hods has been p oposed o cha ac e ise he de e io a ion o mic oo ganisms o syn he ic pain binde s. These me hods a e based on op ical and scanning elec on mic oscopy (SEM) (Mo iyama Y (1993): 231; Cappi elli e al. 2005: 49), spec opho ome y (Abdel- Ka eem O. (2000): 1, Cappi elli e al. 2005: 49), de e mina ion o he weigh loss o specimens inocula ed wi h selec ed mic oo ganisms (Koes le R.J. and San o o E.D. (1988)) o he cha ac e isa ion o s uc u al changes by means o FTIR and Raman spec oscopy (Cappi elli e al. 2005: 49; Heyn C. e al. (1995): 73) and FTIR-PAS spec oscopy (Cappi elli e al. 2005: 49). Mo e ecen ly, he au ho s o his wo k p oposed an al e na i e analy ical me hod based on py olysis-gas ch oma og apy-mass spec ome y (Doménech-Ca bó M.T. e al. (2006): 1265; Doménech-Ca bó M.T. e al. (2007): 109 and Doménech-Ca bó M.T. e al. in p ess). The gene al pu pose o he p esen wo k is o ca y ou a s udy aimed a he iden i ica ion o he s uc u al changes in alkyd esins aking place a e mic obial a ack. The esul s o his s udy we e ob ained by using “online” ime hylsilyla ion wi h hexame hyldisilazane (HMDS) on wo se ies o es specimens inocula ed wi h selec ed bac e ia and ungi. FTIR spec oscopy was also applied o complemen he ch oma og aphic da a. 2. EXPERIMENTAL 2.1. Sol en s and eagen s AH alkyd esin, supplied by K eme Pigmen e, (Aichs e en, Ge many), was used in his wo k. Addi ionally, glyce ine and pen ae i h i ol by Sigma (S einheim, Ge many) we e used as e e ence ma e ials. )LJXUH3 URJUDPRIDEODQNVDPSOHIURPWKH$ON G$+WKLQ¿OP7KHFRPSRXQGVLGHQWL¿HGZHUH+H[DQRLFDFLG706HVWHU+HSWDQRLFDFLG706HVWHU%HQ]RLFDFLG706HVWHU (4) Oc anoic acid, TMS es e , (5) Ph halic anhyd ide, (6) Nonanoic acid, TMS es e , (7) Decanoic acid, TMS es e , (8) Hep anedioic acid, bisTMS es e , (9) Dodecanoic acid, TMS es e , (10) 1RQDQHGLRLFDFLG$]HODLFELV706HVWHU7HWUDGHFDQRLFDFLG706HVWHU+H[DGHFDQRLFDFLG3DOPLWLF706HVWHUFLV2FWDGHFHQRLFDFLG706HVWHU2FWDGHFDQRLFDFLG (S ea ic), TMS es e 193 ARCHÉ. PUBLICACIÓN DEL INSTITUTO UNIVERSITARIO DE RESTAURACIÓN DEL PATRIMONIO DE LA UPV - Núm. 3 - 2008 S udy on he biode e io a ion o alkyd ah esin used as a binding medium o mode n pain ings by py olysis-gas ch oma og aphy-mass spec ome y and i spec oscopy incuba ed o 15 days. Spo ula ed cul u es we e suspended in 2 mL o Tween 80, 0.1%. A e cen i uga ion, pelle s we e washed and esuspended in 2 mL o dis illed wa e . Suspensions we e il e ed h ough glass wool o elimina e any emains o mycelia. A e he coun in a Neubaue chambe , concen a ion was adjus ed o106 spo es.mL-1. Simila ly, bac e ial suspensions (107-108 cells mL-1) we e ob ained a e cen i uga ion and washed wi h dis illed wa e o elimina e any possible emains o cul u e media. Finally, a single species o he selec ed ungi and bac e ia was inocula ed on each p e iously p epa ed es specimen con aining a single d ied PVA emulsion. Then 20 µL o he a o emen ioned ungal o bac e ial suspensions we e applied on each es specimen, which co e ed an a ea o ca. 20 mm2 o he d ied polyme ic ilm. Th ee eplica es we e p epa ed o each ype o es specimen con aining a single PVA emulsion and a single species o ungus o bac e ium. In pa allel, blank specimens we e p epa ed which had been subjec ed o he same ea men as he specimens excep o inocula ion wi h mic oo ganisms. P e ious expe imen s helped us o es ablish he op imal condi ions o incuba ing he model a nish specimens. Specimens we e incuba ed o 15 days in da kness a 28°C and 85% RH, wa e ac i i y (aw)=0.85. A e wa ds, he biomass o mic oo ganisms o med on he inocula ed was comple ely emo ed. P epa a ion o samples o Py-GC-MS analysis A sample was aken by sc aping abou 1 µg o he polyme ic ilm om he inocula ed a ea o each alkyd specimen exposed o he mic obial a ack wi h he help o a scalpel. The same p ocedu e was ca ied ou o ob ain a blank sample om he blank specimens, which had no been inocula ed. Th ee eplica es o each sample o blank and each sample o inocula ed a ea we e analysed o each specimen ype. Good epea abili y was ob ained as shown by he ela i e s anda d de ia ion alues ob ained in he se o analyses pe o med in he ange o 1-5%. Samples we e placed in o a mic o qua z py olysis ube, hen wo small po ions o qua z wool we e in oduced in o bo h sides o he qua z ube o a oid unwan ed displacemen s o he sample. A e wa ds, 2 PL o HMDS we e added. Finally, he sample was placed in he py olysis coil and in oduced in o he py olysis in e ace, which was kep a 250ºC. Resin specimens p epa a ion A se ies o specimens we e ob ained wi h he comme cial p oduc s and sp ead as a hin laye (a e age hickness, 50-80 Pm) on glass slides. Specimens we e s o ed a oom empe a u e o 2 weeks a e which hey we e analysed. Cul u e media: T yp one Soy B o h (TSB) medium (Scha lau Chemie, Ba celona, Spain) was used o bac e ia cul u es, while comple e medium (CM), composed o yeas ex ac 0.5%, mal ex ac 0.5% and glucose 1%, was used o ungal cul u es. Mic oo ganism inocula ion and incuba ion The mic oo ganisms s udied we e ecognised biode e io a ion agen s and we e selec ed a e an ex ensi e e iew o he li e a u e (Abdel-Ka eem O. (2000): 1, Cappi elli e al. 2005: 49 Doménech- Ca bó M.T. e al. (2006): 1265; Giacobini C. and Fi pi M. (1981): 203; Giacobini C. e al. (1988): 418; Giacobini C. e al. (1991): 275) om among he ungi and bac e ia species suscep ible o o igina e p ocesses o biode e io a ion in syn he ic esins. All he species s udied we e ubiqui ous sap ophy es, which a e abundan ly dis ibu ed in he a mosphe e, and came om collec ion s ocks o he Spanish Collec ion o Type Cul u es (CECT, Colección Española de Cul i os Tipo). The mic oo ganisms used we e: Fungi: Aspe gillus nige (An) (CECT 2088, ATCC 9029), Penicillium ch ysogenum (Pc) (CECT 2306, ATCC 8537), T ichode ma pseudokoningii (Tp) (CECT 2937), Cladospo ium cladospo ioides (Cc) (CECT 2110, ATCC 16022), Chae omium globosum (Cg) (CECT 2701, ATCC 6205), Rhizopus o yzae (Ro) (CECT 2339, ATCC 11145), Au eobasidium pullulans (Ap) (CECT 2703, ATCC 9348). Bac e ia: S ep omyces cellulo ans (Sc) (CECT 3242, ATCC 29806), Bacillus amylolique aciens (Ba) (CECT 493, ATCC 23842), A h obac e oxydans (Ao) (CECT 386, ATCC 14358), Bu kholde ia cepacia (Bc) (CECT 322, ATCC 17759). In o de o ob ain ungal spo es, lyophilised collec ion s ocks we e hyd a ed in CM b o h and incuba ed o 1 week (28ºC, 75% RH). A e wa ds, cul u es we e sp ead on solid CM medium and Figu e 2.- IR abso p ion spec um o a blank sample o alkyd AH specimen (do ed line) and om a sample inocula ed wi h he ungus Cladospo ium cladospo ioides (Cc) (con inuous line). 194 ARCHÉ. PUBLICACIÓN DEL INSTITUTO UNIVERSITARIO DE RESTAURACIÓN DEL PATRIMONIO DE LA UPV - Núm. 3 - 2008 E alua ion o he e ec o mic o o ganism inocula ion FTIR spec oscopic analyses o inocula ed samples we e also pe o med. In gene al, he IR abso p ion spec a a e simila and show a sligh b oadening o he s e ching ib a ion asc ibed o he o ma ion o alipha ic ca boxylic acids o med by hyd olysis, as shown in Figu e 2. Wi h hose specimens subjec ed o inocula ion and incuba ion wi h mic oo ganism, py og ams simila o hose o un ea ed specimens we e ob ained, and no new compounds we e iden i ied as esul o he me abolic ac i i y o he es ed bac e ia. Ne e heless, some ema kable quan i a i e di e ences we e obse ed among he uninocula ed and blank samples depending on he bac e ium. The peak a ea a io (R) o he se o TMS de i a i es o bo h he sho - chain a y mono acids and diacids in ela ion he TMS de i a i es o palmi ic acid ha e been used o assessing he quan i a i e changes ha ake place as a esul o he bac e ia a ack. So R = 6Asho chain a y acids/Apalmi ic acid whe e Asho chain a y acids is he alue o he peak a ea o each indi idual TMS de i a i e o he sho chain a y acid and Apalmi ic acid is he alue o he peak a ea o he TMS de i a i e o he palmi ic acid ob ained in he py og am. High R alues sugges ha a signi ican b eaking o he a y acids ha o m he polyme ic chains esul ed a e he mic obial a ack. 3. RESULTS AND DISCUSSION Cha ac e iza ion o alkyd AH hin ilms Table 1 summa ises he main compounds iden i ied in he blank samples excised om he uninocula ed a ea o he specimens. These same compounds can be seen in he py og am shown in Figu e 1 co esponding o a blank sample. The py og am o he Alkyd AH esin, p epa ed as a hin ilm, is domina ed by he peaks co esponding o he ime hylsilyl (TMS) de i a i e o benzoic acid (3) and ph alic anhyd ide (5), which we e he main compounds ob ained in he py olysis o he alkyd esin (Lea ne T., (1995): 76). TMS de i a i es o palmi ic (12) and s ea ic (14) sa u a ed a y acids and oc adecenoic (13) unsa u a ed a y acid we e iden i ied, which we e also di ec py olysis p oduc s o he s udied esin. A numbe o sho -chain a y mono and diacids also appea in he py og am, which p obably o med du ing he incuba ion p ocess applied o he specimens and accoun o he b eaking down p ocess aking place in he polyme ic chains. The esul s ob ained by means o Py-GC-MS a e in good ag eemen wi h hose o FTIR spec oscopy. Figu e 2 shows he IR abso p ion spec um ob ained in he ATR mode om a blank sample. The spec um is domina ed by he p ominen abso p ion bands co esponding o a s e ching ib a ion es e bond om benzoa e a 1718 cm-1, he asymme ic s e ching ib a ion o C(=O)-O o he es e g oup a 1241 cm-1, he asymme ic s e ching ib a ion o C-C-O o he a oma ic es e g oup a 1107 and he asymme ic s e ching ib a ion o C-C-O o he a oma ic es e g oup 1059 cm-1. Figu e 5.- Ba cha illus a ing he R alues ob ained om he se o sho chain a y mono acids occu ing in he samples o blank and inocula ed specimens wi h he selec ed ungi. Figu e 6.- Ba cha illus a ing he R alues ob ained om he se o sho chain a y diacids occu ing in he samples o blank and inocula ed specimens wi h he selec ed ungi. Figu e 3.- Ba cha illus a ing he R alues ob ained om he se o sho chain a y mono acids occu ing in he samples o blank and inocula ed specimens wi h he selec ed bac e ia. Figu e 4.- Ba cha illus a ing he R alues ob ained om he se o sho chain a y diacids occu ing in he samples o blank and inocula ed specimens wi h he selec ed bac e ia. Ma ía Te esa Doménech-Ca bó, Gio ana Bi ossi, Juana de la C uz-Cañiza es, Fe nando Bolí a -Galiano, Ma ia del Ma López-Mi as, Julio Rome o-Nogue a, Inés Ma ín-Sánchez, José Vicen e Gimeno-Adelan ado and An onio Doménech-Ca bó 195 ARCHÉ. PUBLICACIÓN DEL INSTITUTO UNIVERSITARIO DE RESTAURACIÓN DEL PATRIMONIO DE LA UPV - Núm. 3 - 2008 CONCLUSIONS - A numbe o sho -chain a y mono and diacids also appea in he py og am. They a e p obably o med du ing he incuba ion p ocess ca ied ou wi h he specimens and accoun o he b eaking down p ocess aking place in he polyme ic chains. - Wi h hose specimens subjec ed o inocula ion and incuba ion wi h mic oo ganism, py og ams simila o hose o un ea ed specimens we e ob ained, and no new compounds we e iden i ied as esul o he me abolic ac i i y o he es ed bac e ia and ungi. - The mos ema kable quan i a i e di e ences in he expe imen al R alues om he blank samples and om hose samples om he inocula ed a eas o he specimen we e obse ed o he bac e ium A h obac e oxydans (Ao). - The mos ema kable quan i a i e di e ences in he expe imen al R alues om blank samples and om hose samples om he inocula ed a eas o he specimen we e obse ed o he ungus Cladospo ium cladospo ioides (Cc) . ACKNOWLEDGEMENTS Financial suppo is g a e ully acknowledged om he Spanish “I+D+I MEC” p ojec CTQ2005-09339-CO3-01, 02 and 03, which a e also suppo ed by ERDEF unds, and we a e g a e ul o he SB2005- 0031 p ojec asc ibed o he p og amme o pos doc o al s ages o no el esea che s in Spanish uni e si ies and esea ch cen es om he Spanish Minis y o Educa ion and Science (MEC). REFERENCES Abdel-Ka eem O. (2000): “Mic obiological es ing o polyme s and esins used in conse a ion o linen ex iles” in 15 h Wo ld Con e ence on Nondes uc i e Tes ing, Rome, 1-10. Specimens inocula ed wi h bac e ia The ba cha shown in Figu e 3 illus a es he R alues ob ained om he se o sho -chain a y mono acids occu ing in he samples o he blank and inocula ed specimens wi h he selec ed bac e ia. In e es ingly, an inc ease o he R alue was obse ed in he inocula ed samples, apa om hose ea ed wi h S ep omyces cellulo ans bac e ium. This sugges s ha , in gene al, he bac e ia a ack encou ages he b eaking down o he a y acid p esen in he alkyd chains which esul s in he o ma ion o sho -chain a y mono acids. Figu e 4 shows he ba cha illus a ing he R alues co esponding o he se o sho -chain a y diacids. In his case, a di e en beha iou was no ed o he ou bac e ia es ed. A simila R alue o ha o he blank was obse ed in he samples om he specimens inocula ed wi h A h obac e oxydans and Bu kholde ia cepacia, whe eas an R alue lowe han ha om he blank was no ed in he specimens inocula ed wi h S ep omyces cellulo ans and Bacillus amylolique aciens. Specimens inocula ed wi h ungi The ba cha shown in Figu e 5 illus a es he R alues ob ained om he se o sho -chain a y mono acids occu ing in he samples o blank and inocula ed specimens wi h he selec ed ungi. In e es ingly, a signi ican inc ease in he R alue was seen in he sample inocula ed wi h Cladospo ium cladospo ioides. The es o specimens exhibi ed simila o lowe R alues han hose no ed in he blank. Simila esul s we e ound o he R co esponding o he se o R alues ela ing o he se o sho -chain a y diacids, as illus a ed in Figu e 6. Thus, he sample om he specimen inocula ed wi h Cladospo ium cladospo ioides showed a highe R alue han ha o he blank, whe eas a simila o lowe R alue o ha o he blank was obse ed in he samples om specimens inocula ed wi h he emaining ungi. Peak Compound iden i ied (min) 1 Hexanoic acid, TMS es e 9.25 2 Hep anoic acid, TMS es e 10.70 3 Benzoic acid, TMS es e 11.67 4 Oc anoic acid, TMS es e 11.85 5 Ph halic anhyd ide 12.66 6 Nonanoic acid, TMS es e 12.86 7 Decanoic acid, TMS es e 13.76 8 Hep anedioic acid, bisTMS es e 15.12 9 Dodecanoic acid, TMS es e 15.37 10 Nonanedioic acid (Azelaic), bis TMS es e 16.46 11 Te adecanoic acid, TMS es e 16.80 12 Hexadecanoic acid (Palmi ic), TMS es e 18.10 13 11-cis-Oc adecenoic acid, TMS es e 19.15 14 Oc adecanoic acid (S ea ic), TMS es e 19.30 7DEOH0DLQFRPSRXQGVLGHQWL¿HGLQWKHDQDO VLVRI$ON G$+VSHFLPHQVDQGWKHLUUHWHQWLRQWLPH S udy on he biode e io a ion o alkyd ah esin used as a binding medium o mode n pain ings by py olysis-gas ch oma og aphy-mass spec ome y and i spec oscopy 196 ARCHÉ. PUBLICACIÓN DEL INSTITUTO UNIVERSITARIO DE RESTAURACIÓN DEL PATRIMONIO DE LA UPV - Núm. 3 - 2008 Giacobini C., Fi pi M. 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(2004): The Biode e io a ion o Synhe ic Resins Used in Conse a ion” Mac omolecula Bioscience, 4 399-405, and e e ences he ein. Cappi elli F., Vicini S., Piaggio P., Abb usca o P., P inci E., Casade all A., Nosanchuk J.D., Zanandini E. (2005): „In es iga ion o Fungal De e io a ion o Syn he ic Pain Binde s Using Vib a ional Spec oscopic Techniques“ Mac omolecula Bioscience. 5 49-57 Doménech-Ca bó M.T., Ose e-Co ina L., de la C uz-Cañiza es J., Bolí a - Galiano F., Rome o-Nogue a J., Ma ín-Sánchez I., Fe nández-Vi as M.A. (2006): “S udy on he mic obiodeg ada ion o e penoid esins-based a nishes om easel pain ing using py olysis-gas ch oma og aphy-mass spec ome y and gas ch oma og aphy-mass spec ome y”, Analy ical and Bioanaly ical Chemis y. 385 1265-1280. Doménech-Ca bó M.T., Bi ossi G., Ose e-Co ina L., Yusá-Ma co D.J., Bolí a -Galiano F., López-Mi as M.M., Fe nández-Vi as M.A., Ma ín- Sánchez I. (2007): “In oduc ion o he s udy on he biode e io a ion o he poly( inyl) ace a e esin mowili h 50 using FTIR spec oscopy and py olysis- gas ch oma og aphy-mass spec ome y” A ché. 2 109-114. Doménech-Ca bó M.T., Bi ossi G., de la C uz-Cañiza es J., Bolí a -Galiano F., López-Mi as M.M., Rome o-Nogue a J., Ma ín-Sánchez I., “Mic obial de e io a ion o Mowili h DMC 2, Mowili h DM5 and Con ay poly( inyl ace a e) emulsions used as binding media o pain ings by py olysis-silyla ion- gas ch oma og aphy–mass spec ome y”, Jou nal o Analy ical and Applied Py olysis, in p ess. TITULO: Es udio del biode e io o en esinas alquídicas usadas como aglu inan e en pin u as mode nas median e espec oscopía FTIR y pi ólisis-c oma og a ía de gases-espec ome ía de masas (Py-GC-MS). RESUMEN: Se ha lle ado a cabo una e aluación median e espec oscopía FTIR y pi ólisis-c oma og a ía de gases- espec ome ía de masas (Py-GC-MS) de las al e aciones causadas en esinas alquídicas come icales po mic oo ganismos. Es e ul imo mé odo incluye la de i a ización “on line” du an e la pi ólisis de las esinas alquídicas usando hexame ildisilazano. A al in se han usado p obe as cons i uidas po películas inas de esina aplicadas sob e id ios po aobje os. Los análisis e ec uados sob e una se ie de p obe as inoculadas con di e sos géne os de bac e ias y hongos y pos e io men e cul i adas en condiciones óp imas ponen de mani ies o que el a aque de mic oo ganismos p o oca la o u a de las cadenas polimé icas y la apa ición de ácidos g asos de cadena co a. Una se ie de bandas de abso ción IR asociadas a g upos ca boxílicos que apa ecían en las mues as inoculadas con hongos así como el inc emen o del con enido de ácidos g asos de cadena co a de ec ado median e Py-GC-MS con i man es os esul ado y sugie en que los p ocesos me abólicos en es os mic oo ganismos son más signi ica i os que los asociados a bac e ias. PALABRAS CLAVES: esina alquídicas, aglu inan es, Py-GC-MS, biode e io o, FTIR spec oscopy Ve sión española Ma ía Te esa Doménech-Ca bó, Gio ana Bi ossi, Juana de la C uz-Cañiza es, Fe nando Bolí a -Galiano, Ma ia del Ma López-Mi as, Julio Rome o-Nogue a, Inés Ma ín-Sánchez, José Vicen e Gimeno-Adelan ado and An onio Doménech-Ca bó