Titre : |
The role of fungi isolated from historical vegetable-tanned leather on the degradation of peptides and amino acids |
Type de document : |
texte imprimé |
Auteurs : |
Gomaa Abdel-Maksoud, Auteur ; Tharwat F. Tadros, Auteur ; Hany Gad, Auteur |
Année de publication : |
2014 |
Article en page(s) : |
p. 1-7 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Acides aminés Les acides aminés (ou aminoacides) sont une classe de composés chimiques possédant deux groupes fonctionnels : à la fois un groupe carboxyle –COOH et un groupe amine –NH2. Parmi ceux-ci, les acides α-aminés se définissent par le fait que leur groupe amine est lié à l'atome de carbone adjacent au groupe acide carboxylique (le carbone α), ce qui leur confère la structure générique H2N–CHR–COOH, où R représente la chaîne latérale, qui identifie l'acide α-aminé.
Les acides α-aminés jouent un rôle fondamental en biochimie comme constituants élémentaires des protéines : ils polymérisent en formant des liaisons peptidiques qui aboutissent à de longues chaînes macromoléculaires appelées peptides. Alternaria Aspergillus Champignons microscopiques Cuirs et peaux -- Détérioration Hydrolyse enzymatique Pénicilliums Peptides Tannage végétal
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Index. décimale : |
675 Technologie du cuir et de la fourrure |
Résumé : |
Large numbers of leather artefacts are found in many places in Egypt such as libraries, museums, storehouses, mosques and churches. Many aspects of deterioration especially fungal stains are found on the surface of items such as bookbindings due to unfavourable environmental conditions (such as increased temperature, relative humidity, light, air pollutants etc.). This paper aims to isolate and identify fungi from vegetable-tanned leather bookbindings; study the effect of highly proteolytic fungi in the hydrolysis of leather into peptides and free amino acids, and determination of amino acid content of accelerated aged leather produced using fungi.
To achieve this, we isolated and identified fungi from three historical bookbindings. Peptide nitrogen and free amino acids were estimated for up to 90 days of incubation. The effect of microbial ageing of the leather on the amino acid content was also studied. The results revealed that the most frequently found fungi were Aspergillus spp., Penicillium spp. and Alternaria spp. The enzymatic activity of these fungi towards the degradation of gelatin was much higher when a phosphate buffer was used in the media than when a citrate buffer was used. The results are expressed as clear zone (mm). Peptide and free amino acids increased during incubation times of up to 90 days. Hydrolysis plays an important role in the deterioration after infection with the studied fungi. |
Note de contenu : |
- MATERIALS AND METHODS : Isolation and identification of fungi - Activating spore species - Preparing spore suspension - Qualitative investigation of fungal proteolytic activity of gelatin - Quantitative estimation of gelatin degradation in culture media by fungal species - The effect of microbial ageing by fungi on the amino acid content of leather - Preparation of the samples for amino acid analysis
- RESULTS AND DISCUSSION : Isolation and identification of fungi - Estimation of peptide nitrogen
- AMINO ACID ANALYSIS |
En ligne : |
https://drive.google.com/file/d/12W28PF1G23A6Aoxicud-QrTtJipdVbFB/view?usp=drive [...] |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=21018 |
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 98, N° 1 (01-02/2014) . - p. 1-7