Design of a capillary viscometer for assay or collagenase activity by "continuous" observation of the hydrolysis of a soluble collagen with a time of flight flowmeter / Samuel M. Mozersky in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXXXI, N° 10 (10/1996)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXXXI, N° 10 (10/1996) . - p. 263-269 Titre : Design of a capillary viscometer for assay or collagenase activity by "continuous" observation of the hydrolysis of a soluble collagen with a time of flight flowmeter Type de document : texte imprimé Auteurs : Samuel M. Mozersky, Auteur ; David G. Bailey, Auteur Année de publication : 1996 Article en page(s) : p. 263-269 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The design of a capillary viscometer for semi automated assay of collagenase activity is described. The rate of flow of a solution of a soluble derivative of collagen undergoing hydrolysis by the collagenase is measured "continuously" by an electronic flow meter. Since the reciprocal of the flow-rate is proportional to the viscosity and the latter is a (double exponential decay) function of the collagenase concentration (as well as of time), collagenase concentration can be determined from the flowrate at a given incubation time. The data are collected automatically, stored in a computer, and analyzed at the analyst's convenience. The viscometer is suitable for use in research laboratories investigating damage to hides (and therefore to leather) caused by bacterial digestion of collagen. En ligne : https://drive.google.com/file/d/12KH7lJZFUSBibEbZKbcB8Ya5PA_Vxrbz/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=7788 [article]

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Hide powder azure and azocoll as substrates for assay of the proteolytic activity of bate / Samuel M. Mozersky in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXXVII, N° 8 (08/1992)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXXVII, N° 8 (08/1992) . - p. 287-295 Titre : Hide powder azure and azocoll as substrates for assay of the proteolytic activity of bate Type de document : texte imprimé Auteurs : Samuel M. Mozersky, Auteur ; David G. Bailey, Auteur Année de publication : 1992 Article en page(s) : p. 287-295 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Collagène Confitage enzymatique Enzymes pancréatiques Poudre de peaux Protéolyse En biochimie, la protéolyse est la segmentation des protéines en ses fragments de base (acides aminés) via l'hydrolyse catalysée par des enzymes dits "protéolytiques" (protéases ou hydrolases). (Wikipedia) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Hide powder azure (HPA) and azocoll (Az) were evaluated for their suitability as collagen-rich substitutes for casein in assaying for the proteolytic activity of bate. Optimum conditions were established and a recommended procedure is presented. Under these conditions, the proteolytic activity of bate can be evaluated using an incubation period of one minute. Commercially available HPA and Az of small particle size were both found to be suitable substrates, provided the prescribed conditions are carefully observed. Evaluation of a commercially available preparation of coarse Az indicated that it is less suitable as a substrate for the assay. Note de contenu : - Incubation buffer - Agitation - Termination of enzyme action - Washing the substrate - Time course of proteolysis - Influence of the amount of bate - Pancreatic bate - Precision - Recommended procedure - Table 1 : Precision of measurement of reaction velocity En ligne : https://drive.google.com/file/d/1kFYIu78JLplzs6CVejKWxTa2W9jwWtAw/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39841 [article]

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Measurement of the proteolytic activity of bate in drum liquor / Samuel M. Mozersky in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXXVIII, N° 8 (08/1993)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXXVIII, N° 8 (08/1993) . - p. 283-290 Titre : Measurement of the proteolytic activity of bate in drum liquor Type de document : texte imprimé Auteurs : Samuel M. Mozersky, Auteur ; David G. Bailey ; Marvin A. Baynes, Auteur Année de publication : 1993 Article en page(s) : p. 283-290 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : A colorimetric procedure has been developed for assay of the proteolytic activity of bate in drum liquor using hide powder azure, a commercially available substrate. Stock bate powders or solutions can be assayed with the same procedure.Results of the application of the assay to tannery samples are presented and the potential use of the procedure for quality control is discussed. The cost of chemicals and single-use equipment for a single assay is $4.00, and the run time 30 minutes.Fifteen samples can be run by one operator "simultaneously", i.e., with a one minute delay between one sample and the next. The procedure has a relative standard deviation of less than 5%. En ligne : https://drive.google.com/file/d/1miUnWJSGsqYYVCt5WYXxhmeDQAO4DSYX/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=8161 [article]

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Optimization of the assay of bate and drum liquor for proteolytic activity / Samuel M. Mozersky in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXXX, N° 8 (08/1995)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXXX, N° 8 (08/1995) . - p. 235-242 Titre : Optimization of the assay of bate and drum liquor for proteolytic activity Type de document : texte imprimé Auteurs : Samuel M. Mozersky, Auteur ; Marvin A. Baynes, Auteur ; David G. Bailey, Auteur Année de publication : 1995 Article en page(s) : p. 235-242 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : In two recent publications from this laboratory, procedures were described for measuring the proteolytic activity of bate and (bate-containing) drum liquor using hide powder azure (HPA) as substrate. Subsequent to that work, it was found that HPA sometimes loses much of its sensitivity to proteolytic enzymes of storage. This led to a study of the substrate and of related factors affecting the assay, which resulted in substantial revision of the assay procedure, as follows. HPA is activated prior to use by reduction of particle size and a mild heat treatment, and200mg used per assay (instead of 50mg). A clarified extract of the sample to be assayed is introduced into the incubation tube (a 25 mm ´ 150 mm screw-cap tube) instead of the crude material. Since proteolytic activity was found to change by 10 to 15% per °C, good temperature control is necessary; for research purposes, a water-bath shaker-incubator operating at 37°C and 400 rpm is recommended. Incubation time has been reduced from 20 min to 10 min at ambient temperature (ca. 25°C), 5 min at 37°C. These modifications have resulted in the following advantages: (1) substantially increased sensitivity, (2) a linear dependence of the color measured on enzyme concentration, and (3) improved reproducibility. En ligne : https://drive.google.com/file/d/1m4ZmYp-cbBTCpJwnoL3XdK7s8DMhbC5P/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=7931 [article]

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Viscometric assay of collagenase activity using a stop reagent to terminate enzyme action / Samuel M. Mozersky in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. XCII, N° 3 (03-04/1997)

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. XCII, N° 3 (03-04/1997) . - p. 62-69 Titre : Viscometric assay of collagenase activity using a stop reagent to terminate enzyme action Type de document : texte imprimé Auteurs : Samuel M. Mozersky, Auteur ; David G. Bailey, Auteur Année de publication : 1997 Article en page(s) : p. 62-69 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : A simple, precise viscometric assay procedure has been developed for the assay of true collagenase activity. The substrate is a commercially available pepsin-treated mammalian skin collagen. It comes as a solution which needs no treatment other than pH adjustment and dilution prior to its incorporation into the assay medium. Viscosity is measured after enzymatic action is terminated with a Stop Reagent. Any one of a wide variety of viscometers can be used, including a simple Ostwald-type viscometer. Other advantages of the procedure are also discussed. The temperature during incubation and viscometry should be controlled within + or – 0,1°C. Such control is easily achieved with an inexpensive controller. Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=7683 [article]

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