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Alternative technologies for adding value to bovine hair waste / B. C. Galarza in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 94, N° 1 (01-02/2010)
[article]
Titre : Alternative technologies for adding value to bovine hair waste Type de document : texte imprimé Auteurs : B. C. Galarza, Auteur ; I. Cavello, Auteur ; C. A. Greco, Auteur ; R. Hours, Auteur ; M. M. Schuldt, Auteur ; Carlos S. Cantera, Auteur Année de publication : 2010 Article en page(s) : p. 26-32 Note générale : Bibliogr. Langues : Anglais (eng) Tags : Cuir Peau Epilage Valorisation Perte Poils bovin Caractéristiques morphologiques structurales chimiques Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Considerations on the immunization phenomenon.
Morphological, structural and chemical characteristics of hair.
The effects on hair-saving unhairing on hair.
En ligne : https://drive.google.com/file/d/1JF7Ez_PSrrzCx5Y7meGp4F2p59SCIje4/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=8308
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 94, N° 1 (01-02/2010) . - p. 26-32[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 011957 - Périodique Bibliothèque principale Documentaires Disponible Characterization and evaluation of fungal enzymatic pool with unhairing activity / B. C. Galarza in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 100, N° 5 (09-10/2016)
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Titre : Characterization and evaluation of fungal enzymatic pool with unhairing activity Type de document : texte imprimé Auteurs : B. C. Galarza, Auteur ; M. Garro, Auteur ; J. Martegani, Auteur ; R. Hours, Auteur Année de publication : 2016 Article en page(s) : p. 257-262 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Caractérisation
Cuirs et peaux -- Analyse
Cuirs et peaux de bovins
Enzymes fongiques
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
Microscopie électronique à balayageIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : The use of enzymes in the leather industry in the beamhouse area to partially replace sulfide, can reduce to almost 50% the H2S emission. In this enzyme treatment proteolysis needs to be controlled to prevent the extension of activity to collagen. Collagen must keep its optimal conditions for the tannage process and to give high quality leather. In this sense it is necessary to characterize the enzyme from the physicochemical point of view and to study the morphological changes produced in bovine skin to control its action. An enzymatic pool of geophilic strain Trichophyton ajelloi cultured in solid media was characterized. Azocaseinolytic and keratinolytic activity was determined under different conditions. The enzymatic pool showed tolerance to high T°, optimal pH9 in bath substrates, partial inhibition in concentrations 0.1M, 0.01M and 0.001 M from metallic salts (Ca Cl2, BaCl2, KCl, CuSO4), activation by NaCl, reducing agents as Na2S03, Na2S, L-cystein hydrochloride monohydrate, thioglycolic acid and commercial anionic and non-ionic surfactants (SDS, isogràs AN, Triton, Baymol, Azymol). Inactivation exerted by. PMSF showed a serine-protease as a component of the pool (MEROPS system). When the enzymatic pool was applied for 24-48 hours under optimal conditions on bovine skin pieces, a depilatory affect was observed. The changes in the bovine skin morphology were observed by SEM, alter fixation in formaldehyde and dehydration with alcohol as part of a tentative protocol for bovine skin analysis by SEM (Scanning Electron Microscopy). Note de contenu : - Solid-state culture
- Characterization of crude extract
- Test procedures
- SEM : sample preparation and observationEn ligne : https://drive.google.com/file/d/1Cn1wPo2dkSvZQZ62tGJGbpyJQQ1Ylr7Q/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=27091
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 100, N° 5 (09-10/2016) . - p. 257-262[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 18411 - Périodique Bibliothèque principale Documentaires Disponible Fungal biotransformation of bovine hair : Assessment of structural changes / B. C. Galarza in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 91, N° 6 (11-12/2007)
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Titre : Fungal biotransformation of bovine hair : Assessment of structural changes Type de document : texte imprimé Auteurs : B. C. Galarza, Auteur ; Maria Laura Garro, Auteur ; Ivana Alejandra Cavello, Auteur ; M. C. Cazau, Auteur ; R. A. Hours, Auteur ; Carlos S. Cantera, Auteur Année de publication : 2007 Article en page(s) : p. 229-232 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Champignons microscopiques
Déchets industriels -- Recyclage
Déchets organiques -- Recyclage
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.
Poils -- BiodégradationIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : The hair-saving unhairing process generates another solid waste in the beamhouse area, regardless of the process used. Changes in unhairing technology have altered the problem of the high organic load and suspended solids of the beamhouse liquid effluent into a new problem : the disposal of the concentrated hair waste.
Given that daily generation of ‘hair waste’ is considerable (approx. 2.5 tons per 1000 salted bovine hides processed) and that this waste can be considered as a raw material due to its physical and chemical properties, it is interesting to orientate our activities towards the investigation and development of technological alternatives to facilitate adding value.
A typical analysis of the ‘hair waste’ after a hair saving unhairing process is within the following ranges.
Total solids: 25-30%, total nitrogen: 11-15%, Ca++: 2-3%, Na+: 1-2%, S: 3-5%, (% moisture-free basis), sulphides :
80-100mgH2S/kg of recovered wet hair (filtered and drained, moisture 75%).
The relevant organic component of the hair is the fibrous keratin protein which is very resistant to hydrolysis by chemical-physical and biological methods. Keratin has high stability as a consequence of the disulphide bridges of cysteine amino acid between adjacent protein chains.
Biodegradation of hair by fungi is among the relevant alternatives to add value to ‘hair waste’. Using the waste as a solid substrate for fungal growth, a higher bioavailability is achieved for further use in agricultural technology for example. Moreover, this process offers the attractive concept of ‘feedback’, because biodegradation generates an enzymatic extract with potential applications in leather technology.Note de contenu : - OBJECTIVES
- MATERIALS AND METHODS : Isolation of fungus with keratinolytic activity
- RESULTS : Sample observation by Scanning Electron Microscopy
- Table 1 : Specific enzymatic activity of the extract on different substrates, protein concentration and the final content of biomass of the culture
- Table 2 : Comparison of the proteolytic activity of the fungal extract and commercial preparationsEn ligne : https://drive.google.com/file/d/1kLrOXHodiSIj0FUc8-yaNSHmcO5haDJu/view?usp=share [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39003
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 91, N° 6 (11-12/2007) . - p. 229-232[article]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)
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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 -- BiodégradationIndex. 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 extractsEn ligne : https://drive.google.com/file/d/1Mrbx0x1BGf1ZNG_jsl1LMyTL1SX9KH-J/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39634
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 3 (05-06/2004) . - p. 93-98[article]Fungal biotransformation of bovine hair. Part 2 : Biomass and proteases produced as a function of incubation time. Assessment of hair waste digestion / B. C. Galarza in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 90, N° 4 (07-08/2006)
[article]
Titre : Fungal biotransformation of bovine hair. Part 2 : Biomass and proteases produced as a function of incubation time. Assessment of hair waste digestion Type de document : texte imprimé Auteurs : B. C. Galarza, Auteur ; L. M. Goya, Auteur ; M. L. Garro, Auteur ; J. Mercerat, Auteur ; R. A. Hours, Auteur ; Carlos S. Cantera, Auteur Année de publication : 2006 Article en page(s) : p. 169-172 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cuirs et peaux
CystineLa cystine est un acide aminé composé de deux unités cystéine liées par un pont disulfure.
Déchets -- Valorisation
Détérioration fongique
Epilage
Microscopie
Peptidases
Poils -- BiodégradationIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : Unlike the conventional hair-saving unhairing processes, the modern processes considerably reduce the organic load from the beamhouse liquid effluent and yet a partially degraded 'hair waste' is generated, which has to be properly disposed of. It is estimated that a tannery processing 25 ton of salted cow hides will recover about 2.5 ton of wet hair per day.
As was mentioned in the first part of the series 'Fungal biotransformation of bovine hair' the aim of our activities is to produce structural changes in the ‘hair waste’ using it as a solid substrate for the growth of the fungal species Trichophyton ajelloi and therefore weakening the keratinís resistance to hydrolysis processes.
A strain of this microorganism, which was isolated from a Yak yard, has proved to be able to generate an enzymatic system capable of degrading hair keratin by means of specific proteases: the keratinases. Fungal activity also gave place to an enzymatic extract with activity upon the protein substrates of the epidermis and dermis of bovine hide.
It should be noted that reports on fungal pathogenesis indicated that Trichophyton ajelloi presents no pathogenicity for men or animals.
Upgrading the 'hair waste' by fungal biotransformation implies considering it as a raw material and not taking the current modality of 'throwing away proteins' to the soil (cost of transport and disposal of waste in landfills).
Biodegradation offers on the one hand the attractive concept of 'feedback' since hair is the solid substrate upon which fungi act generating a degraded organic waste and a protein extract with proteolytic activity (keratinolytic among others) whose unhairing activity is evaluated. On the other hand an intermediate stage would be generated in the transformation of the ‘hair waste’ with potential uses in vermiculture and vermicompost.Note de contenu : - OBJECTIVES
- MATERIALS AND METHODS : Culture conditions of the microorganism - Analytical techniques - Assessment of the degree of digestion of the ‘hair waste’
- RESULTS AND DISCUSSION : Microscopy observations - Assessment of digestibility - Cystine assessment in the ultrafiltered crude extract - Final remarks
- Table 1 : Hair digestibilityEn ligne : https://drive.google.com/file/d/1fYmDuf6dOPGGOroT0Iv-Raf9r9NFKTRb/view?usp=share [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39116
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 90, N° 4 (07-08/2006) . - p. 169-172[article]The activity of the hair follicle and its relation to the defects of the grain layer / M. L. Garro in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 90, N° 4 (07-08/2006)
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