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  1. Artikel: Biocleaning of starch glues from textiles by means of α-amylase-based treatments

    Tortora, Mariagrazia / Gherardi, Francesca / Ferrari, Enrico / Colston, Belinda

    Applied microbiology and biotechnology. 2020 June, v. 104, no. 12

    2020  

    Abstract: Glues based on starch are widely used for the consolidation of brittle fibres in historic and archaeological textiles. Ageing fabrics are affected by hydrolysis/oxidation and cross-linking of these glues, a decrease of glues’ solubility, the formation of ...

    Abstract Glues based on starch are widely used for the consolidation of brittle fibres in historic and archaeological textiles. Ageing fabrics are affected by hydrolysis/oxidation and cross-linking of these glues, a decrease of glues’ solubility, the formation of cracks, and discoloration. The hydrolytic action of enzymes on starch-based glues is promising, as molecular recognition offers great selectivity. However, a systematic assessment of the best methods for applying enzymatic formulations has not been explored yet. Here, α-amylase was applied either by pipetting a solution or combining with gellan gel (embedded in the gel or spread on the gel surface). The effectiveness of the different formulations on the removal of potato and wheat starch was evaluated by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and colorimetric measurements. Enzymes dispersed in gel showed weak diffusion at the surface, resulting in poor starch breakdown and removal. On the contrary, amylase applied by pipette and spread on gel resulted in high starch removal selectivity and efficiency, with neither swelling nor damage to the fibres. These results validate protocols for the assessment of the enzymatic activity on glue-consolidated fibres, identify best application methods and confirm the excellent properties of amylase dispersions for the conservation of historic and archaeological textiles.Key points• Application of α-amylase by pipette and combined with gellan gel to remove starch glues from wool.• Systematic assessment of the best application methods following a multi-analytical protocol.• Enzymes dispersed in gel exhibit poor diffusion at the surface, leading to weak starch removal.• Enzymes applied by pipette and spread on gel are efficient in starch cleaning, without damage to the fibres.
    Schlagwörter Fourier transform infrared spectroscopy ; alpha-amylase ; archaeology ; biotechnology ; brittleness ; colorimetry ; crosslinking ; discoloration ; enzyme activity ; gels ; hydrolysis ; microbiology ; oxidation ; potatoes ; protocols ; solubility ; starch ; wheat starch ; wool
    Sprache Englisch
    Erscheinungsverlauf 2020-06
    Umfang p. 5361-5370.
    Erscheinungsort Springer Berlin Heidelberg
    Dokumenttyp Artikel
    Anmerkung NAL-AP-2-clean
    ZDB-ID 392453-1
    ISSN 1432-0614 ; 0171-1741 ; 0175-7598
    ISSN (online) 1432-0614
    ISSN 0171-1741 ; 0175-7598
    DOI 10.1007/s00253-020-10625-9
    Datenquelle NAL Katalog (AGRICOLA)

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  2. Artikel ; Online: Biocleaning of starch glues from textiles by means of α-amylase-based treatments.

    Tortora, Mariagrazia / Gherardi, Francesca / Ferrari, Enrico / Colston, Belinda

    Applied microbiology and biotechnology

    2020  Band 104, Heft 12, Seite(n) 5361–5370

    Abstract: Glues based on starch are widely used for the consolidation of brittle fibres in historic and archaeological textiles. Ageing fabrics are affected by hydrolysis/oxidation and cross-linking of these glues, a decrease of glues' solubility, the formation of ...

    Abstract Glues based on starch are widely used for the consolidation of brittle fibres in historic and archaeological textiles. Ageing fabrics are affected by hydrolysis/oxidation and cross-linking of these glues, a decrease of glues' solubility, the formation of cracks, and discoloration. The hydrolytic action of enzymes on starch-based glues is promising, as molecular recognition offers great selectivity. However, a systematic assessment of the best methods for applying enzymatic formulations has not been explored yet. Here, α-amylase was applied either by pipetting a solution or combining with gellan gel (embedded in the gel or spread on the gel surface). The effectiveness of the different formulations on the removal of potato and wheat starch was evaluated by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and colorimetric measurements. Enzymes dispersed in gel showed weak diffusion at the surface, resulting in poor starch breakdown and removal. On the contrary, amylase applied by pipette and spread on gel resulted in high starch removal selectivity and efficiency, with neither swelling nor damage to the fibres. These results validate protocols for the assessment of the enzymatic activity on glue-consolidated fibres, identify best application methods and confirm the excellent properties of amylase dispersions for the conservation of historic and archaeological textiles.Key points• Application of α-amylase by pipette and combined with gellan gel to remove starch glues from wool.• Systematic assessment of the best application methods following a multi-analytical protocol.• Enzymes dispersed in gel exhibit poor diffusion at the surface, leading to weak starch removal.• Enzymes applied by pipette and spread on gel are efficient in starch cleaning, without damage to the fibres.
    Mesh-Begriff(e) Adhesives/chemistry ; Diffusion ; Hydrolysis ; Microscopy, Electron, Scanning ; Polysaccharides, Bacterial ; Solanum tuberosum/chemistry ; Solubility ; Spectroscopy, Fourier Transform Infrared ; Starch/chemistry ; Textiles ; Triticum/chemistry ; alpha-Amylases/metabolism
    Chemische Substanzen Adhesives ; Polysaccharides, Bacterial ; gellan gum (7593U09I4D) ; Starch (9005-25-8) ; alpha-Amylases (EC 3.2.1.1)
    Sprache Englisch
    Erscheinungsdatum 2020-04-22
    Erscheinungsland Germany
    Dokumenttyp Journal Article
    ZDB-ID 392453-1
    ISSN 1432-0614 ; 0171-1741 ; 0175-7598
    ISSN (online) 1432-0614
    ISSN 0171-1741 ; 0175-7598
    DOI 10.1007/s00253-020-10625-9
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel ; Online: Immobilized Enzymes on Gold Nanoparticles: From Enhanced Stability to Cleaning of Heritage Textiles.

    Gherardi, Francesca / Turyanska, Lyudmila / Ferrari, Enrico / Weston, Nicola / Fay, Michael W / Colston, Belinda J

    ACS applied bio materials

    2019  Band 2, Heft 11, Seite(n) 5136–5143

    Abstract: Enzyme-based treatments are used in heritage conservation for the effective removal of glues and other damaging organic layers from the surfaces of historic and artistic works. Despite their potential, however, the application of enzymatic treatments is ... ...

    Abstract Enzyme-based treatments are used in heritage conservation for the effective removal of glues and other damaging organic layers from the surfaces of historic and artistic works. Despite their potential, however, the application of enzymatic treatments is currently limited because of their poor efficiency and low operational and environmental stability. We demonstrate the use of α-amylase immobilized on gold nanoparticles to improve the efficacy of enzymatic treatments enhancing both the reactivity and the stability of the formulations. Gold nanoparticles coated with α-amylase exhibit significant advantages compared to free enzymes. We report up to 5× greater resistance to environmental changes, up to 2× higher efficacy toward removal of starch-based glues from textiles and deeper penetration through the fibers, without causing damage or inducing salt precipitation. These results offer exciting prospects for the development of enzymatic formulations, both for heritage conservation and the wider application of enzymes, such as in medicine, the detergent industry, and green chemistry.
    Sprache Englisch
    Erscheinungsdatum 2019-11-04
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ISSN 2576-6422
    ISSN (online) 2576-6422
    DOI 10.1021/acsabm.9b00802
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Zeitschrift: Use of Metal Ion Indicators to Determine Complex Stability Constants: The Method of Competitive Equilibration

    Colston, Belinda J. / Robinson, Vincent J.

    The Analyst (London) : The Analytical Journal of The Royal Society of Chemistry

    1997  Band 122, Seite(n) 1451–1455

    Abstract: An einem einfachen Modell, naemlich der Reaktion von Zink(II)-Ionen mit Xylenolorange in Konkurrenz mit der Zink-Sulfat-Reaktion wurde die Anwendbarkeit von Berechnungsverfahren ueberprueft, welche zur theoretischen Ermittlung der Erhoehung der ... ...

    Abstract An einem einfachen Modell, naemlich der Reaktion von Zink(II)-Ionen mit Xylenolorange in Konkurrenz mit der Zink-Sulfat-Reaktion wurde die Anwendbarkeit von Berechnungsverfahren ueberprueft, welche zur theoretischen Ermittlung der Erhoehung der Loeslichkeit von Metallionen durch Komplexbildung verwendet werden. Solche Berechnungen sind erforderlich, um die Ausbreitung von Radionukliden im Grundwasser abzuschaetzen. Besonders wichtig erschien der Nachweis, dass die Abhaengigkeit der Gleichgewichtskonstanten von der Ionenstaerke der Loesung bis zu Werten von 0,1 m mit hinreichender Genauigkeit durch die halbempirische Davies-Gleichung wiedergegeben wird.
    Schlagwörter Zink ; Radionuklid ; Chemische Reaktion ; Modellierung ; Reaktionsgleichgewicht ; Komplexbildung ; Komplexbildner ; Migration ; Ionen ; Mathematische Methode ; Sulfat ; Chemische Kenngroesse ; Berechnungsverfahren ; pH-Wert ; Absorption ; Schadstoffausbreitung ; Grundwasser ; Loeslichkeit ; Gleichung
    Sprache Englisch
    Dokumenttyp Zeitschrift
    Datenquelle OPAC und UmweltLIteraturDATenbank (ULIDAT) des Umweltbundesamtes (UBA)

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