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675 : Technologie du cuir et de la fourrure |
Ouvrages de la bibliothèque en indexation 675
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Enzymatic hydrolysis of limed trimmings : preparation, characterization and application of collagen hydrolysate / Mohammed Hussein in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXII, N° 2 (02/2017)
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Titre : Enzymatic hydrolysis of limed trimmings : preparation, characterization and application of collagen hydrolysate Type de document : texte imprimé Auteurs : Mohammed Hussein, Auteur ; Satiesh Kumar Ramadass, Auteur ; Balaraman Madhan, Auteur ; Jonnalagadda Raghava Rao, Auteur Année de publication : 2017 Article en page(s) : p. 44-51 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Agents de tannage
Chromatographie
Collagène
Colorants -- Absorption
Cuirs et peaux -- Propriétés organoleptiques
Hydrolysats de protéines
Hydrolyse enzymatique
Retannage
Spectrométrie de masse
TrypsineLa trypsine (EC 3.4.21.4) est une enzyme digestive du suc pancréatique qui a pour rôle de digérer les protéines.
Elle est synthétisée par le pancréas sous forme de trypsinogène (proenzyme inactive), puis stockée dans les vésicules enzymatiques des cellules acineuses d'où elle est excrétée au moment de la digestion. L'activation du trypsinogène en trypsine est le résultat de l'hydrolyse d'un propeptide sous l'action de l'entérokinase ou par un effet d'autoactivation de la trypsine par elle-même. La cholecystokinine-pancréozymine active la sécrétion des enzymes (donc de la trypsine) dans le suc pancréatique.
La trypsine est une endoprotéase qui hydrolyse les liaisons peptidiques dans lesquelles un acide aminé basique (Lys-|-Xaa ou Arg-|-Xaa) engage sa fonction acide (sauf dans le cas où l'acide aminé suivant (schématisé ici par "Xaa") est une Proline). Elle coupe en C-terminal de ces acides aminés. En d'autres mots, elle transforme les chaînes polypeptides en chaînes protéiques plus courtes pour permettre la digestion. Efficace à pH 7,5 - 8,5, elle est inactivée et digérée en quelques heures à pH neutre (=7) dans l'intestin.
La trypsine participe à l'activation d'autres enzymes comme l'alpha-chymotrypsine par coupure hydrolytique de la chaîne polypeptidique du chymotrypsinogène.
Cette enzyme sert également lors de la 2e semaine du développement embryonnaire humain. Elle est sécrétée par le trophoblaste afin de digérer la zone pellucide entourant le blastocyste. Ce phénomène s'appelle l'éclosion.Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Limed pelt trimmings are one of the solid wastes that are generated in leather processing. These wastes are valuable resources for producing collagen hydrolysate, which can be potentially used for retanning of leathers. This work establishes the preparation, characterization and application of collagen hydrolysate by enzymatic hydrolysis of limed trimmings. The collagen hydrolysate was prepared using various concentration of trypsin. The hydrolysate samples were characterized using Fast Protein Liquid Chromatography (FPLC) and Matrix Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) techniques. About 6 predominant fractions of collagen hydrolysate peptides were observed from the enzymatic hydrolysis. The molecular weight of collagen hydrolysates was observed to be in the range between 1750 and 5800 daltons. The collagen hydrolysates prepared using various concentration (0.8, 1.0 and 1.2%) of trypsin were used for retanning process. The collagen hydrolysate product obtained from hydrolysis with (0.8% trypsin, 3 hours) exhibited better dye uptake when used as retanning agent. Furthermore, collagen hydrolysate retanned leathers exhibited very good strength properties in comparison to leathers processed using control protein syntan. The option of internalizing the waste on one side and using them as a substitute for a high value product on the other presents the utilization of limed trimming as a strong case for sustainable leather manufacture. Note de contenu : - EXPERIMENTAL : Materials - Methods (preparation of collagen hydrolysate) - Characterization of the collagen hydrolysage fast protein liquid chromatography (FPLC) - Matrix assisted laser desorption/ionization (MALDI-TOF) - Application of collagen hydrolysate in retanning - Determining percent absorption of CH - Determining the percent absorption of dye - Physical strength characteristics of crust leathers - Quantification of color of the leathers - Organoleptic evaluations of crust leathers
- RESULTS AND DISCUSSION : Trypsin hydrolysis of limed trimmings - Fast protein liquid chromatography (FPLC) - Matrix assisted laser desorption/ionization (MALDI-TOF) of collagen hydrolysate - Absorption of collagen hydrolysate - Percent absorption of dye - Physical strength properties - Quantification of colors of the leathers - Organoleptic properties - Collagen hydrolysages : an alternative syntanEn ligne : https://drive.google.com/file/d/1Hk_k86EJ7lZGRwo9NJ-3tqwvb9rA0jry/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=27884
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CXII, N° 2 (02/2017) . - p. 44-51[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 18697 - Périodique Bibliothèque principale Documentaires Disponible Enzymatic hydrolysis of skin shavings for preparation of collagen hydrolysates with specified molecular weight distribution / Chi Yuanlong in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 96, N° 1 (01-02/2012)
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Titre : Enzymatic hydrolysis of skin shavings for preparation of collagen hydrolysates with specified molecular weight distribution Type de document : texte imprimé Auteurs : Chi Yuanlong, Auteur ; Cui Min, Auteur ; Cui Xiaoju, Auteur ; Wenhua Zhang, Auteur ; Xuepin Liao, Auteur ; Bi Shi, Auteur Année de publication : 2012 Article en page(s) : p. 16-20 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Collagène
Cuirs et peaux -- Déchets
Hydrolysats de protéines
Hydrolyse enzymatiqueTags : 'Copeaux tannerie' 'Protéase 1398' 2709' Alcalase Papaïne Pepsine 537' Trypsine 'Titration formaldehyde' Electrophorèse 'Ges dodécyl sulfate-polyacrylamide sodium' 'Ultrafiltration centrifuge' Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Collagen hydrolysates were extracted from tannery skin shavings through enzymatic hydrolysis by using protease 1398, protease 2709, alcalase, papain, pepsin, protease 537 and trypsin, respectively. The hydrolytic degree and molecular weight distribution (MWD) of the hydrolysages were evaluated by the formaldehyde titration method, sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), tricine-SDS-PAGE and centrifugal ultrafiltration. It was found that the MWD of the as prepared collagen hydrolysates has a close correlation with the hydrolytic degree, and greatly depends on the enzyme employed. The low molecular weight (MW) collagen hydrolysates, with relatively high hydrolytic degree, were obtained by enzymatic hydrolysis using protease 1398, protease 2709, papain and alcalase. More than 60% (mass ratio) of the fractions in these four hydrolysates were in the molecular weight range of <10kDa. The use of protease 537 produced medium-MW collagen hydrolysages where 40% of the fractionswere of 10-30kDa. The high-MW collagen hydrolysages that include about 66% fractions with molecular weights higher than 20kDa were obtained by using pepsin, accompanied by the lowest hydrolytic degree. This research provides a potential approache for molecular weight and molecular weight distribution control collagen hydrolysates by enzymatic hydrolysis ot tannery skin wastes. Note de contenu : - MATERIALS AND METHODS : Materials - Methods - Determination of hydrolytic degree of collagen - SDS-PAGE and tricine-SDS-PAGE determination - Centrifugal ultrafiltration analysis
- RESULTS AND DISCUSSION : Hydrolytic degree analysis
- SDS-PAGE and tricine-SDS-PAGE patterns - Centrifugal ultrafiltration analysis on MWDEn ligne : https://drive.google.com/file/d/1NEe4OCKiTxbrMEX3emn2sQFAzagsFJQc/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=13549
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 96, N° 1 (01-02/2012) . - p. 16-20[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13659 - Périodique Bibliothèque principale Documentaires Disponible Enzymatic membrane reactor for eco-friendly goat skin unhairing / A. Cassano in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 84, N° 5 (09-10/2000)
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Titre : Enzymatic membrane reactor for eco-friendly goat skin unhairing Type de document : texte imprimé Auteurs : A. Cassano, Auteur ; E. Drioli, Auteur ; R. Molinari, Auteur ; D. Grimaldi, Auteur ; F. La Cara, Auteur ; M. Rossi, Auteur Année de publication : 2000 Article en page(s) : p. 205-211 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Caractérisation
Cuirs et peaux de chèvres
Déchets -- Réduction
Enzymes protéolytiquesUne enzyme protéolytique est une enzyme capable de couper une protéine en plusieurs fragments ou peptides. La trypsine, la papaïne, la pepsine, la chymotrypsine, la plasmine, la subtilisine... sont capables de couper une protéine, chaque enzyme étant spécifique de certains sites particuliers de cette protéine. C'est ainsi, par exemple, qu'une immunoglobuline G est découpée par la papaïne en un fragment Fc et deux fragments Fab, comme l'a montré Porter en 1959.
Epilage enzymatique
Essais (technologie)
Filtration
Produits chimiques -- Consommation -- Réduction
Récupération (Déchets, etc.)Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : A new approach is proposed in order to solve current problems in the dehairing process. An enzymatic agent was used as an alternative to conventional chemical dehairing methods. Ultrafiltration of the enzymatic dehairing bath was carried out during the unhairing operation thus creating an enzymatic membrane reactor for the production of dehaired skins.
The operating system, analytical measurements and microscopical observations on the treated skins in comparison with the control group (lime-sulphide process) are reported and discussed.
The results obtained show the possibility to reduce the environmental impact caused mainly by the aqueous stream coming from conventional dehairing. Other advantages obtained using the coupled enzymatic/UF system were: control of enzyme action; reduction of sulphide requirement: easy recovery of hair with consequent reduction of polluting load and of cleaning-up costs; the possibility of reusing the recovered hair ; simplification of wastewater cleaning-up processes : increased opening-up of the fibre structure and production of softer leather; plus the possibility of avoiding the bating operation, thus obtaining savings in terms of time, work, water and chemicals.Note de contenu : - MATERIALS AND METHODS : Proteolytic enzyme - Unhairing tests - Unhairing tests in the enzyme membrane reactor
- RESULTS AND DISCUSSION : Enzyme activity characterisation - Experimental unhairing tests - Unhairing tests in the EMR - Enzyme/sulphide comparison
- Table 1 : Recipe used for enzymatic unhairing coupled with ultrafiltration (initial weight of dry skins kg 12.5)
- Table 2 : Analyses of fat substances on soaked and dehaired skins
- Table 3 : Physical testing on leather samples unhaired with the conventional method (lime and sodium suiphide) and with the enzymatic method (experimental group)
- Table 4 : Chemical testing on leather samples unhaired with the conventional method (lime and sodium suiphide) and with the enzymatic method (experimental group)En ligne : https://drive.google.com/file/d/1M8cX_NobVvN45WfAJOyhiK0eZtrSurX7/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=40918
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 84, N° 5 (09-10/2000) . - p. 205-211[article]Enzymatic modification of hydrolysis products from collagen using a microbial transglutaminase. I. Physical properties / Maryann M. Taylor in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. XCVI, N° 9 (09/2001)
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Titre : Enzymatic modification of hydrolysis products from collagen using a microbial transglutaminase. I. Physical properties Type de document : texte imprimé Auteurs : Maryann M. Taylor, Auteur ; Luisa F. Cabeza, Auteur ; William N. Marmer, Auteur ; Eleanor M. Brown, Auteur Année de publication : 2001 Article en page(s) : p. 319-332 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : In previously reported research from this laboratory, gelatins, both commercial and experimental of varying gel strengths, were chemically modified using glutaraldehyde, glyoxal, and carbodiimide. These classical modifications effectively changed the physical and functional properties of gelatin; however, they have drawbacks in that the crosslinking agents are potentially toxic. Transglutaminase is an enzyme capable of forming inter- or intra-molecular cross-links in many proteins. The enzyme catalyzes an acyl transfer reaction between the g-carboxamide group of peptide-bound glutamine residues as acyl donors and primary amines as acceptors. When the e-amino group of peptide-bound lysine acts as acyl acceptor, an e-(g-glutamyl) lysine cross-link is formed. This enzyme, now isolated by fermentation, is commercially available, relatively inexpensive, and environmentally safe. We modified gelatins of varying quality with microbial transglutaminase. Gel strengths of low bloom gelatins improved with increasing enzyme concentrations, whereas the gel strengths of higher bloom gelatins either remained the same or decreased with increasing enzyme concentrations. All gelatins gave higher melting points with increasing amounts of enzyme, some even higher than 90ºC. Viscosities, measured at 60ºC and at or near room temperature, increased with increasing enzyme concentrations. The temperature of gelation, as described in the literature, increased not only with the quality of the gelatin but also with increasing enzyme concentrations. Potential applications for this enzyme in by-product utilization and possibly the leather-making process are numerous. En ligne : https://drive.google.com/file/d/1wvenobFOzHHSyBVxHpPVwLjdWfOQ9qxk/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=4363
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Code-barres Cote Support Localisation Section Disponibilité 001566 - Périodique Bibliothèque principale Documentaires Disponible Enzymatic modification of hydrolysis products from collagen using a microbial transglutaminase. II. Preparation of films / Maryann M. Taylor in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. XCVII, N° 6 (06/2002)
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Titre : Enzymatic modification of hydrolysis products from collagen using a microbial transglutaminase. II. Preparation of films Type de document : texte imprimé Auteurs : Maryann M. Taylor, Auteur ; Cheng-Kung Liu, Auteur ; Nicholas P. Latona, Auteur ; William N. Marmer, Auteur ; Eleanor M. Brown, Auteur Année de publication : 2002 Article en page(s) : p. 225-234 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The use of renewable resources in the production of goods traditionally made from petroleum products has recently gained increasing research interest. Environmental concerns, such as biodegradability and ever increasing landfill fees, could be allayed by use of these products. During the conversion of hides and skins into leather, a high percentage of the original collagen substrate becomes waste. This waste has potential for recycling into useful products. Historically, gelatins (a collagen by-product) have been modified chemically, and the physical properties of these products have been improved. However, because of cost and the toxicity issues associated with some crosslinking chemicals, enzymatically modified products would be highly desirable. Commercial gelatins were treated enzymatically with a microbial transglutaminase, mixed with glycerol as plasticizer, and films were prepared. It was found that the amount of glycerol added affected the mechanical properties, particularly the maximum strain. Increasing the concentration of cross-linking agent gave products with higher tensile strengths that were less soluble in water and had improved water absorption properties. The products resulting from these studies have implications not only in the preparation of edible films and sausage casings, but also in the packaging material market, a market not previously utilized because of poor mechanical properties of gelatin films. En ligne : https://drive.google.com/file/d/1su4LsTGTT8SqZfWaqGbeArqyVz3oJwhB/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=4291
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. XCVII, N° 6 (06/2002) . - p. 225-234[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 001575 - Périodique Bibliothèque principale Documentaires Disponible Enzymatic modification of hydrolysis products from collagen using a microbial transglutaminase. III. Preparation of films with improved mechanical properties / Maryann M. Taylor in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. XCVIII, N° 11 (11/2003)
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PermalinkEnzymatic reactions and phylogenetic analysis of haloveratile bacteria isolated from çamalti saltern salt samples used in the leather industry / Pinar Caglayan in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXIV, N° 12 (12/2019)
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PermalinkEnzymatic removal of melamin in enzyme based dehairing and fiber opening / Punitha Velmurugan in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CIII, N° 7 (07/2008)
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PermalinkEnzymatic treatment of offal from fleshing machines / M. M. Taylor in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXXIV (Année 1989)
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PermalinkEnzyme hydrolysis of solid tannery wastes : solid state enzyme production / R. Chakraborty in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 82, N° 2 (03-04/1998)
PermalinkEnzyme unhairing - An eco-friendly biotechnological process / Wang Rui in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 93, N° 2 (03-04/2009)
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PermalinkEnzyme unhairing of pigskins / W. Jonczyk in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 72 (Année 1988)
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PermalinkEnzyme unhairing of skins in recycled liquors - A way to utilize the waste bath / Jian Song in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 96, N° 6 (11-12/2012)
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PermalinkEnzymes in leather making / BLC Leather Technology Centre in LEATHER INTERNATIONAL, Vol. 214, N° 4823 (08/2012)
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PermalinkEnzymes in retanning for cleaner blue stock / John W. Mitchell in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. XCIII, N° 8 (10/1998)
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PermalinkEnzymes in the tannery - Catalysts for progress ? in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXXIII (Année 1988)
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PermalinkEpidermis morphology : investigation of cattle hide during unhairing by transmission electron microscope / He Xian-Xian in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 96, N° 3 (05-06/2012)
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PermalinkEpoxidized methyl ricinoleate bio-plasticizer with a pendant acetate ester for PVC artificial material : circumventing existing limit on achievable migration resistance / Siyu Pan in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 1 (Année 2019)
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PermalinkEpoxy resin cross-linked binders in aqueous finishing / Anna Bacardit in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 94, N° 1 (01-02/2010)
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