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]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 90, N° 4 (07-08/2006) . - p. 169-172 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 Cystine La cystine est un acide aminé composé de deux unités cystéine liées par un pont disulfure. Déchets -- Valorisation Détérioration fongique Epilage Microscopie Peptidases Poils -- Biodégradation Index. 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 digestibility En ligne : https://drive.google.com/file/d/1fYmDuf6dOPGGOroT0Iv-Raf9r9NFKTRb/view?usp=share [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39116 [article]

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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)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 90, N° 4 (07-08/2006) . - p. 164-168 Titre : The activity of the hair follicle and its relation to the defects of the grain layer Type de document : texte imprimé Auteurs : M. L. Garro, Auteur ; Carlos S. Cantera, Auteur ; B. C. Galarza, Auteur Année de publication : 2006 Article en page(s) : p. 164-168 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cuirs et peaux -- Défauts Cuirs et peaux de bovins Follicule pileux Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Practices in the tanning industry may result in the occurrence of possible damage on the grain surface and grain layer that can spoil the quality of leather. The so called ‘large follicle defect,’ a natural damage associated with the characteristics of coat and the hair growth cycle, is a defect attracting the attention of researchers because of its morphological characteristic distribution and periodicity in wet-blue, semi-finished, finished, full grain and corrected grain leathers. Due to the lack of information on this defect in journals concerning leather making and to the need to understand the nature of the defect with the purpose of guiding process modifications to minimize its adverse effects, follicle rhythm and details are considered in this report. Knowledge of hair follicle activity and the correlation between coat shedding and the variation in environmental conditions during the seasons of the year consolidate the hypothesis that the defect is associated with the natural process of hair shedding. This is particularly observed in the phase during which shedding reaches its maximum levels and it is related to the hair deeply anchored in the grain layer during the progress of the Telogen and the Anagen phases (evolution of the shedding hair and expulsion of inactive hair). Note de contenu : - Description and explanation of the defect : Naked eye observation - Observation under binocular magnifier (x50) and light microscope (x100) - The purpose of the article - Considerations about the activity of hair follicles : Hair follicle growth cycle - Determination of the activity state of hair follicle - Hypothesis on the cause of the ‘large follicle defect’ and possible growth pattern in the bovine hide - Final remarks En ligne : https://drive.google.com/file/d/12seYp4QBMHG7wj8B5upUKP-9040X3sVe/view?usp=share [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39115 [article]

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