Dépouillements

Fungal biotransformation of bovine hair : Part 1 - Isolation of fungus with keratinolytic activity / B. C. Galarza in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 3 (05-06/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 3 (05-06/2004) . - p. 93-98 Titre : Fungal biotransformation of bovine hair : Part 1 - Isolation of fungus with keratinolytic activity Type de document : texte imprimé Auteurs : B. C. Galarza, Auteur ; L. M. Goya, Auteur ; Carlos S. Cantera, Auteur ; Maria Laura Garro, Auteur ; H. E. Reinos, Auteur ; Laura M. I. Lopez, Auteur Année de publication : 2004 Article en page(s) : p. 93-98 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Bovins Détérioration fongique Poils -- Biodégradation Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The present study reports on the results of the “fungal biodegradation” of “hair waste” in a static solid medium using previously isolated strains of Trichophyton ajelloi and Fusarium oxysporum. The main purpose of the research programme is to upgrade the hair by biodegradation, to consider it as a raw material instead of the current modality of “throwing away” proteins to landfill and to its reuse in agricultural technology, directly or after composting and applying earthworms to generate an organic fertilizer (“vermicompost”). The fungal activity on the hair gives a degraded organic material and an extract with a pool of proteases with, amongst others, keratinolytic activity,. The enzyme activities expressed by the fungal extract are evaluated against soluble, insoluble, synthetic, and skin protein component substrates. Relationships between the different specific activities are defined to evaluate and predict the possible behaviour of the fungal extracts in the beamhouse processes. Note de contenu : - Solid state culture - Objectives - Experimental Development : Materials and Methods - Protocol of the analysis for activity assessment - Results and Discussion : Assessment of enzymatic activities of crude extracts - Aminopeptidase Activity. Determination of kinetic constants - Assessment of the degree of hair digestion - Protein profile and Isoelectric Focusing (IEF) - Zymogram - Comments on mechanisms of fungal digestion of hair - Fungal extracts in the soaking, unhairing and bating processes. Possible applications - Table 1 : Proteolytic activity of the fungal extracts of the different substrates - Table 2 : Activity Relationships for Trichophyton ajelloi and Fusarium oxysporum fungal extracts En ligne : https://drive.google.com/file/d/1Mrbx0x1BGf1ZNG_jsl1LMyTL1SX9KH-J/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39634 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Prevention of halophilic microbial damage on brine cured hide by extremely halophilic halocin producer strains / Meral Birbir in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 3 (05-06/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 3 (05-06/2004) . - p. 99-104 Titre : Prevention of halophilic microbial damage on brine cured hide by extremely halophilic halocin producer strains Type de document : texte imprimé Auteurs : Meral Birbir, Auteur ; S. Erylmaz, Auteur ; Ayse Ogan, Auteur Année de publication : 2004 Article en page(s) : p. 99-104 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Antimicrobiens Bactéries halophiles Cuirs et peaux -- Conservation Halocines Microbiologie Peaux brutes -- Salage Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Tuz Lake and its salterns; Kayacik, Kaldirim and Tuzkoy Salt Mine in Central Anatolia are the major salt sources of Turkey. Crude salt extracted from these sources is commonly used in hide preservation. Proteolytic activity of extremely halophilic microorganisms, present in the salt used for hide preservation, can digest the grain surface of hides. Many bactericides have therefore, been used in the leather industry to prevent damage by halophiles. However, natural proteinaceous antimicrobial substances such as halocins which are produced by halophilic archaea may be an effective and pollution free alternative to inhibit the proteolytic halophilic archaea in brine solutions. The above reason prompted us to conduct a microbial survey of the salt and brine samples collected from different salt sources in Turkey. A total of 56 extremely halophilic strains were isolated from these salt sources. It was found that 67% of the Tuzkoy Salt Mine and Kaldirim Saltern strains had gelatinase activity. Kayacik Saltern had the highest number of gelatinase positive strains (71%), while the Tuz Lake had the lowest number of gelatinase positive strains (63%). Seven out of 19 Tuz Lake strains, 16 out of 18 Kaldirim Saltern strains, 2 out of 7 Kayacik Saltern strains and 10 out of 12 Tuzkoy Salt Mine strains produced halocins effective against each other. The most potent halocin producers were found in Kaldirim Saltern and the Tuzkoy Salt Mine. All the cells of halocin producers were Gram negative, motile and most of them were pleomorphic. The susceptibilities to different antibiotics of the halocin producer strains were examined and antibiotic test results indicated that these strains were of the family Halobacteriaceae. Although many gelatinase negative halocin producers were isolated from different salt sources, the KYS1 strain was found to be the most effective strain in inhibiting all gelatinase positive strains of Kayacik Saltern and some of the other gelatinase positive strains which could not be inhibited by the Tuz Lake and Tuzkoy Salt Mine strains. It is suggested that gelatinase negative halocin producers or their halocin extracts may be used in preventing the halobacterial deterioration that can occur during brine curing of hides. Note de contenu : - MATERIALS AND METHOODS - ISOLATION OF HALOPHILIC MICROORGANISMS : Gelatinase activity - Halocin activity - Morphological, cultural and physiological characteristics - Antibiotic tests - RESULTS : Microbiological analyses - Isolation of halophilic microorganisms - Gelatinase activity - Halocin Activity - Cell and colony morphology - Salt tolerance - Antibiotic tests - Table 1 : Average number of colonies (per gm salt or ml brine) obtained from different sampling sites - Table 2 : Screening of gelatinase and halocin activities of Tuz Lake strains against each other and KYS1 strains - Table 3 : Screening of gelatinase and halocin activities of Kaldırım Saltern strains against each other and KYS1 strain - Table 4 : Screening of gelatinase and halocin activities of Kayacik Saltern strains against each other - Table 5 : Screening of gelatinase and halocin activities of Tuzkoy Salt Mine strains against each other and KYS1 strain - Table 6 : Frequency of the morphological characteristics of 28 extremely halophilic halocin producers studied - Table 7 : Susceptibility rates of the halocin producer strains to different antibiotics En ligne : https://drive.google.com/file/d/1-JnbM3mZR_C5Q694HQuVebsBc0QBWPb5/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39635 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Synthesis and application of an amphoteric acrylic polyelectryte as a retanning agent / Jin Liqiang in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 3 (05-06/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 3 (05-06/2004) . - p. 105-109 Titre : Synthesis and application of an amphoteric acrylic polyelectryte as a retanning agent Type de document : texte imprimé Auteurs : Jin Liqiang, Auteur ; Liu Zonglin, Auteur ; Xu Qinghua, Auteur ; Li Yanchun, Auteur Année de publication : 2004 Article en page(s) : p. 105-109 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Agents de tannage Composés amphotériques Copolymères -- Synthèse Cuirs et peaux -- Propriétés mécaniques Cuirs et peaux -- Propriétés physiques Cuirs et peaux de porcs Formulation (Génie chimique) Polyacryliques Polyélectrolytes Retannage Tannage au chrome Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : An amphoteric acrylic copolymer of acrylic acid(AA) and methylacrylethyltrimethylammonium chloride (DMC) has been synthesized by free radical copolymerization using ammonium persulfate as the catalyst at 75°C for 4hrs.The structure of the polyelectrolyte has been characterized by FTIR and 13C NMR.The solution properties of the polymer have also been studied. The correlation between the comonomer ratio of the amphoteric polyelectrolyte and its application properties as a retanning material has been investigated by measuring such physical/ mechanical indexes of the retanned leather as thickness increment ratio, shrinkage temperature, tensile strength, unit load elongation and also by instrumental analysis such as scanning electron microscopy (SEM), X-ray diffraction (XRD) and colour analysis. It has been found that the amphoteric polymer tanning agent has a strong retanning ability and has no negative effect on the dyeing of the retanned leather under proper conditions. Note de contenu : - EXPERIMENTAL PROCEDURE : Materials - Preparation of the copolymer - STRUCTURE DETERMINATION OF THE COPOLYMER - SOLUTION PROPERTIES - RETANNAGE APPLICATION : Determination of leather properties - RESULTS AND DISCUSSION : Synthesis of copolymer - SOLUBILITY OF THE COPOLYMER - APPLICATION RESULTS - Table 1 : The reaction conditions and results for preparing the AR series of retannages - Table 2 : Retanning formulation of blue pigskin garment leather - Table 3 : Physical and mechanical propertis of chromed leather retanned by AR series copolymer En ligne : https://drive.google.com/file/d/1I9awenD9B3UvyzDc5202rtW_IRoiiwyN/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39636 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

The effect of fatliquor emulsion on the physical properties of resultant leather / Zongcai Zhang in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 3 (05-06/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 3 (05-06/2004) . - p. 110-112 Titre : The effect of fatliquor emulsion on the physical properties of resultant leather Type de document : texte imprimé Auteurs : Zongcai Zhang, Auteur ; Hong Dai, Auteur ; Juan Du, Auteur Année de publication : 2004 Article en page(s) : p. 110-112 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Chromatographie en phase liquide à hautes performances Cuirs et peaux -- Propriétés physiques Emulsions Granulométrie Produits de nourriture du cuir Tension superficielle Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : This paper reports on a study of the effects of fatliquor emulsion parameters on leather performance. The results show that the emulsion properties, including particle size distribution of emulsion, surface tension and oil (active fat/ neutral oil) content have a great impact on the performance of the resultant leather. The work provides a theoretical foundation for the development of fatliquoring agents. Note de contenu : - MATERIALS AND METHODS : Reagents - Particle size distribution of emulsion - Emulsion stability of fatliquor - Surface tension - Effective component content - Active component contents of the effective component - Stratigraphic testing - Bound oil in leather - Physical properties of resultant leather - RESULTS : Emulsion characteristics of fatliquors - Results of stratigraphic testing - Physical properties of resultant leather - DISCUSSION : Emulsion characteristics and extracted fat content of resultant leather - Emulsion properties and physical properties of resultant leather - Table 1 : HPLC conditions - Table 2 : Emulsion properties of fatliquoring agents - Table 3 : Extracted oil content in the 3 splits of the resultant leather - Table 4 : Physical properties of resultant leathers En ligne : https://drive.google.com/file/d/1LcRnJiFM9i2WpYATw_Z1neYP4WbTywwn/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39637 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

A fast method to determine trace chromium(III) ion in chrome tanning and chrome tanning waste / Zhaoli Wang in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 3 (05-06/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 3 (05-06/2004) . - p. 113-115 Titre : A fast method to determine trace chromium(III) ion in chrome tanning and chrome tanning waste Type de document : texte imprimé Auteurs : Zhaoli Wang, Auteur ; Zhang Xinshen, Auteur ; Hong Dai, Auteur ; Yajun Luo, Auteur Année de publication : 2004 Article en page(s) : p. 113-115 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Chimie -- Essais et réactifs Chimie analytique Chrome trivalent -- Oxydation Ions chrome Tannage -- Déchets Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Large amounts of chromium (III) ion interfere with the determination of trace amounts of chromium (VI) ion in chrome tanning agents. Therefore, a new method was proposed for determination of trace chromium (III) in chrome tanning products and chrome tanning wastes by automatic reference flow injection. After chromium (III) is oxidised to chromium (VI) by potassium periodate, it can be determined by the flow injection function of an automatic metallic elements analyzer using diphenyl carbazide as the colour developing reagent and potassium periodate as the oxidant solution. The effect of the concentration of potassium periodate and the length of the reaction coil were investigated. Under the optimum conditions, the linear range and RSD of the method were 1.00-100ug/ml and 0.84% respectively. The method was applied to the analysis of chrome powder with recoveries ranging from 95.0% to 103.0%. The results satisfy the requirements of the determination. Note de contenu : - EXPERIMENTAL PROCEDURE : Chemical reagents - Apparatus - Preparation of solutions - Analytical procedure - Preparation of the samples - RESULTS AND DISCUSSION : Choice of the absorption wavelength - Choice of length of reaction coil - Choice of oxidant solution - Test of linearity and precision - Recovery tests and analysis of the samples - Analysis of coexisting Chromium (III) ion and Chromium (VI) ion - Table 1 : Precision test - Table 2 : Recovery percentage of Chromium (III) ion - Table 3 : Analytical resuls of samples En ligne : https://drive.google.com/file/d/169F8rw7HgmbKSDJz-yOYpO93MUp5fRjS/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39638 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Modified thrublu chrome tanning for lambskins -Low residual - chrome tannages / Samir Dasgupta in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 3 (05-06/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 3 (05-06/2004) . - p. 116-120 Titre : Modified thrublu chrome tanning for lambskins -Low residual - chrome tannages Type de document : texte imprimé Auteurs : Samir Dasgupta, Auteur Année de publication : 2004 Article en page(s) : p. 116-120 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Couleur Cuirs et peaux -- Propriétés physiques Cuirs et peaux d'agneaux Oxazolidine Tannage au chrome Tannage combiné Le tannage combiné se dit des tannages qui allient deux familles ou genre de tannage pour obtenir un résultat additionnant les qualités complémentaires des tannins mis en œuvre par exemple Chrome-Végétal ou Chrome-Synthétique Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Chrome tanning has for a long time enjoyed a unique position amongst tanners all over the world and almost 90% of all leather produced is chrome tanned. The main reason for this relates to the following characteristics of chrome tanned leather : - high shrinkage temperature/hydrothermal stability - good flexibility - excellent fastness properties - lightweight and not too full - good comfort characteristics - good moulding and shape retention properties High shrinkage temperature, unequalled by any other tannage, has been the paramount feature of these benefits in favour of chrome tanning. A number of studies have been published recently suggesting that chromium (III) itself may be toxic at higher levels under certain ligand environments and also that chromium (VI) is a known carcinogen. In view of this tanners have to consider how best to modify their chrome tanning processes for better chrome exhaustion and also to look for means of minimising any impact on the environment. Note de contenu : - Optimal chrome tanning of lambskins - Optimal chrome/ oxazolidine E combination tanning of lambskins : Modified ThruBlu system for lambskin tannage - Table 1 : Effect of chrome offer (Cr2O3) on shrinkage temperature and chrome levels in leather and exhaust liquor - Table 2 : Colour values of lambskins with different chrome offers - Table 3 : Physical properties of chrome tanned leather with different chrome content - Table 4 : Reduction of chrome in exhaust with oxazolidine E - Table 5 : Comparative properties of chrome tanned leathers - Table 6 : Colour of lambskin leather En ligne : https://drive.google.com/file/d/1U4kzZ9mIig1Rq0dZydh_ps1lnGr6WSOq/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39639 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Hair saving unhairing process : Part 6 - Stratum corneum as a diffusion barrier : Chemical-mechanical injury of epidermis / Carlos S. Cantera in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 3 (05-06/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 3 (05-06/2004) . - p. 121-131 Titre : Hair saving unhairing process : Part 6 - Stratum corneum as a diffusion barrier : Chemical-mechanical injury of epidermis Type de document : texte imprimé Auteurs : Carlos S. Cantera, Auteur ; Maria Laura Garro, Auteur ; L. Goya, Auteur ; L. Barbeito, Auteur ; Betina Galarza, Auteur Année de publication : 2004 Article en page(s) : p. 121-131 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Couche cornée Diffusion (physique) Epilage sulfite de sodium Sulfitolyse Surfactants Trypsine La 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. Urée Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : In this new report of the series ‘Hair saving unhairing process’,we consider the epidermis as a diffusion barrier. The possible macro and micro routes of substance permeation across this tissue and the possible mechanisms of how to injure the stratum corneum and the intercellular inter-intra stratum adhesion are also described. A proposal related to the most important phases of unhairing is also considered, where the so-called Phase I : chemical-mechanical injury of the epidermis is highlighted. The sulphitolysis process, the action of trypsin, SDS, surfactants/solvents and urea are relevant factors to take into account in the above mentioned Phase I. Preliminary results, at laboratory scale, using ‘epidermis substrate’ and fresh hide are described. Note de contenu : - Objectives - Epidermis structure, stratum corneum as a diffusion barrier - Some remarks about trypsin activity : Sulphitolysis process - Action of urea - Action of surfactants - VIII Diffusion of substances across the epidermis - Results of preliminary trials - Trials with 'epidermis substrate' - Sulphitolysis reaction - Behaviour of surfactants/solvents - Trials with fresh hide - Phases of the unhairing process - Table 1 : Influence of Na2SO3, trypsin, surfactants/solvents and urea on "epidermis substrate" En ligne : https://drive.google.com/file/d/1Yblu9_geaYfAuc2I0KztnAv9j2_FeXiF/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39640 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire