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Impact of Portuguese propolis on keratinocyte proliferation, migration and ROS protection: Significance for applications in skin products / Nuno Saraiva in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Vol. 44, N° 3 (06/2022)
[article]
Titre : Impact of Portuguese propolis on keratinocyte proliferation, migration and ROS protection: Significance for applications in skin products Type de document : document électronique Auteurs : Nuno Saraiva, Auteur ; Marisa Nicolai, Auteur ; Marta Martins, Auteur ; Nuno Almeida, Auteur ; Matteo Gusmini, Auteur ; Elisabete Muchagato Maurício, Auteur ; Maria Paula Duarte, Auteur ; Margarida Gonçalves, Auteur ; André Rolim Baby, Auteur ; Ana Fernandes, Auteur ; Catarina Rosado, Auteur Année de publication : 2022 Article en page(s) : p. 333-342 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cellules -- Cultures et milieux de culture
Chimie analytique
Chromatographie
Dermo-cosmétologie
Espèces réactives de l'oxygène
Peau -- Soins et hygiène
Propolis
Tests de sécuritéIndex. décimale : 668.5 Parfums et cosmétiques Résumé : - Objective : Propolis has been used since antiquity, but recent reports of its biological properties hint that it could be employed as a topical pharmaceutical and cosmetic ingredient. This work aims to probe the action of Portuguese propolis extracts on skin cells, providing mechanistic insights into its mode of action and preliminarily assessing its applicability as a skin repair ingredient.
- Methods : The total phenolic content of propolis extracts was measured by the Folin Ciocalteu method. The cytotoxic effect of propolis extracts in human keratinocytes was determined and non-cytotoxic concentrations of the extracts were used to study the impact on collective cell migration, cell cycle and intracellular ROS levels.
- Results : o significant impact was observed in collective cell migration, but one of the extracts mildly increased G2 phase while reducing the % of sub-G1 at a non-cytotoxic concentration. The two extracts with higher phenolic content strongly prevented intracellular cellular ROS accumulation upon exposure to TBHP. Collectively, these results indicate that the putative beneficial effects of propolis extracts in skin repair may not be attributable to induction of collective cell migration but could be partially ascribed to the protection from oxidative stress, which could act in synergy with its well-known antimicrobial activity.
- Conclusion : These data support the applicability of this material in topical and cosmetic formulations and further in vivo assays should be conducted to fully characterize its efficacy and safety.Note de contenu : - MATERIALS AND METHODS : Chemicals - Preparation of propolis extracts and wax fraction - Total phenolic content and chromatographic analysis of the propolis extracts - 2D and 3D HaCaT cell culture - Cell cycle progression of HaCaT cells treated with the propolis extracts - In vitro wound healing assay - Impact of propolis extracts on intracellular reactive oxygen species - Statistical analysis
- RESULTS : Phenolic profile of the propolis ethanolic extracts - Cell viability of HaCaT cells treated with the propolis extracts - Cell cycle progression of HaCaT cells treated with the propolis extracts - In vitro wound healing assay - Impact of propolis extracts on intracellular
reactive oxygen species
- Table 1 : Total phenolic content of propolis extractsDOI : https://doi.org/10.1111/ics.12781 En ligne : https://drive.google.com/file/d/1_f9EPPGbvAUvynjZ9XKivdTaZJuXxNl8/view?usp=shari [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38135
in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE > Vol. 44, N° 3 (06/2022) . - p. 333-342[article]Influence of the chromatographic conditions of the EN ISO 17226-1 standard "determination of formaldehyde content in leather. Part 1. Quantification by HPLC” on the robustness of the method in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXIV, N° 2 (02/2019)
[article]
Titre : Influence of the chromatographic conditions of the EN ISO 17226-1 standard "determination of formaldehyde content in leather. Part 1. Quantification by HPLC” on the robustness of the method Type de document : texte imprimé Année de publication : 2019 Article en page(s) : p. 55-61 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Chimie analytique -- Normes
Chromatographie
Cuir -- Teneur en formaldéhyde
Cuirs et peaux -- Analyse
NormalisationIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : Given the carcinogenic character of formaldehyde, it should be reliably determined in any substrate. The EN ISO 17226 Standard is the Official Method to quantify formaldehyde in leather using either the chromatographic or the colorimetric methods. In cases of discrepancy between results, according to the ISO Organization, preference should be given to the chromatographic method (EN ISO 17226-1 Standard) instead of the colorimetric one (EN ISO 17226-2 Standard). The EN ISO 17226-1 Standard recommends chromatographic conditions of column, mobile phase composition and flow rate.
The paper studies the influence of changes in flow rate, composition of the mobile phase and separating columns recommended by the EN ISO 17226-1 Standard for the determination of formaldehyde content in leather. It has been made relevant that small variations in the flow rate and differences in mobile phase compositions ranging from 35/65 to 45/55 Water/Acetonitrile does not significantly affect the results of formaldehyde concentration.
As regards the different separating columns, non-significant differences between them were observed. However, considering the effectiveness and the retention time of the separating columns, the solid-core particle (Cortecs®C18) column can be recommended because it has in excess the capacity to separate the formaldehyde peak from that of the residual DNPH reagent in less than 2 minutes which is lower than those of the other columns tested. Consequently, the productivity of the analytical laboratories is improved.Note de contenu : - Aim of the work
- Influence of the chromatographic conditions of the EN ISO 17226-1 standard "Determination of formaldehyde content in leather. Part 1. Quantification by HPLC" in the robustness of the method
- MATERIALS AND METHODS : Influence of the flow rate - Influence of the composition of the mobile phase - Influence of the separating columns : retention time and effectivenessEn ligne : https://drive.google.com/file/d/1OfV9TN-H3pjk1Mv92_8owQVm4AJABO5_/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=31718
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CXIV, N° 2 (02/2019) . - p. 55-61[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 20607 - Périodique Bibliothèque principale Documentaires Disponible Ion chromatography with post column derivatization for the determination of hexavalent chromium in dyed leather. Influence of the preparation method and of the sampling location / Mathilde Fontaine in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXII, N° 10 (10/2017)
[article]
Titre : Ion chromatography with post column derivatization for the determination of hexavalent chromium in dyed leather. Influence of the preparation method and of the sampling location Type de document : texte imprimé Auteurs : Mathilde Fontaine, Auteur ; Nicolas Blanc, Auteur ; Jean-Claude Cannot, Auteur ; Claire Demesmay, Auteur Année de publication : 2017 Article en page(s) : p. 319-326 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Chromatographie
Cuir -- Teneur en chrome hexavalent
Cuir teint
Cuirs et peaux -- AnalyseIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : Since 2015, a European restriction limits the hexavalent chromium content to not more than 3 mg/kg in leather products (UE-301-2014, 25 March 2014, §47, annex XVII of REACh). Owing to spectrophotometric interferences encountered with the established European standard EN ISO 17075:2007 when colored leathers have to be analyzed, this article proposes the analysis of hexavalent chromium using ion chromatography with post-column derivatization and spectrophotometric detection. In order to avoid any pre-treatment of the crude extract an on-line solid phase extraction step is introduced by inserting a high capacity reversed phase guard column. The efficiency of the on-line purification is demonstrated (quantitative removal of the dye present in the extract) and allows the direct analysis of crude extracts in less than 6 minutes. The overall chromatographic method is validated following procedures described by the French standard NF T90-210. The measurement error (bias) was determined at 7.2% at the presupposed limit of quantification 5 µg/L (corresponding to a hexavalent chromium content of 0.25 mg/kg in leather) and at the medium concentration level and at 4.0% for the high-level concentration, with relative standard deviations of 5.1%, 2.9% and 2.4% respectively. The recovery yields measured with spiked leathers range from 92 to 96% depending on the hexavalent content. The reliability of the method is also demonstrated through two inter-laboratories test involving several European laboratories. The crucial influence of the sample preparation is also assessed in this work. It is demonstrated that the hexavalent chromium content of leathers is systematically underestimated when the extraction is applied to leathers cut in small pieces and not ground. In parallel, additional tests on leather sampling location show that the shoulder zone is not representative of the rest of the skin in terms of hexavalent chromium content since it has a higher hexavalent chromium content than all other sampling zones. Note de contenu : - EXPERIMENTAL PROCEDURE : Chemicals - Sample preparation - Ion chromatography -
- RESULTS AND DISCUSSION : On-line reversed phase solid phase extraction for dye removing - Validation of the analytical method - Evaluation of the reliability of IC through - Influence of the sample preparation for the analysis - Influence of the sampling location on an entire skinEn ligne : https://drive.google.com/file/d/1sYCmtm9ZvHwlNwYVbhp99LTylkXsDKVJ/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=29246
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CXII, N° 10 (10/2017) . - p. 319-326[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 19286 - Périodique Bibliothèque principale Documentaires Disponible Isolation and purification of caseinase and collagenase from commercial bacillus subtilis AS1.398 enzyme by affinity chromatography / Wang Rui in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 93, N° 1 (01-02/2009)
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Titre : Isolation and purification of caseinase and collagenase from commercial bacillus subtilis AS1.398 enzyme by affinity chromatography Type de document : texte imprimé Auteurs : Wang Rui, Auteur ; Li Zhiqiang, Auteur ; Chen Min, Auteur ; Cheng Haiming, Auteur ; Wang Yingmei, Auteur ; Liao Longli, Auteur Année de publication : 2009 Article en page(s) : p. 8-11 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Bacillus subtilis
Caséinases
Chromatographie
CollagénasesLes collagénases sont des enzymes capables de rompre les liaisons peptidiques du collagène. Elles facilitent la destruction des structures extracellulaires lors de la pathogenèse bactérienne. Ce sont des exotoxines.
La production de collagénases peut être induite lors d'une réponse immunitaire, par les cytokines qui stimulent les cellules telles que les fibroblastes et les ostéoplastes et occasionnent indirectement des lésions tissulaires.
EnzymesUne enzyme est une protéine dotée de propriétés catalytiques. Pratiquement toutes les biomolécules capables de catalyser des réactions chimiques dans les cellules sont des enzymes ; certaines biomolécules catalytiques sont cependant constituées d'ARN et sont donc distinctes des enzymes : ce sont les ribozymes.
Une enzyme agit en abaissant l'énergie d'activation d'une réaction chimique, ce qui accroît la vitesse de réaction. L'enzyme n'est pas modifiée au cours de la réaction. Les molécules initiales sont les substrats de l'enzyme, et les molécules formées à partir de ces substrats sont les produits de la réaction. Presque tous les processus métaboliques de la cellule ont besoin d'enzymes pour se dérouler à une vitesse suffisante pour maintenir la vie. Les enzymes catalysent plus de 5 000 réactions chimiques différentes2. L'ensemble des enzymes d'une cellule détermine les voies métaboliques qui peuvent avoir lieu dans cette cellule. L'étude des enzymes est appelée enzymologie.
Les enzymes permettent à des réactions de se produire des millions de fois plus vite qu'en leur absence. Un exemple extrême est l'orotidine-5'-phosphate décarboxylase, qui catalyse en quelques millisecondes une réaction qui prendrait, en son absence, plusieurs millions d'années3,4. Comme tous les catalyseurs, les enzymes ne sont pas modifiées au cours des réactions qu'elles catalysent, et ne modifient pas l'équilibre chimique entre substrats et produits. Les enzymes diffèrent en revanche de la plupart des autres types de catalyseurs par leur très grande spécificité. Cette spécificité découle de leur structure tridimensionnelle. De plus, l'activité d'une enzyme est modulée par diverses autres molécules : un inhibiteur enzymatique est une molécule qui ralentit l'activité d'une enzyme, tandis qu'un activateur de cette enzyme l'accélère ; de nombreux médicaments et poisons sont des inhibiteurs enzymatiques. Par ailleurs, l'activité d'une enzyme décroît rapidement en dehors de sa température et de son pH optimums.
Produits chimiques -- PurificationIndex. décimale : 547 Chimie organique : classer la biochimie à 574.192 Résumé : Bacillus subtilis is a saprophytic bacteria which has a widespread distribution in nature and can be easily isolated from soil microbes. Bacillus subtilis AS1.398 is a major strain of bacillus subtilis used extensively in light industry and the pharmaceutical industry and is commonly used in the leather industry in China for depilation and bating. The non-collagenolytic activity of caseinase is correlated with the depilation. Collagenolytic protease has little contribution to depilation. It damages the collagen fibres and reduces the quality of leather. Collagenolytic activity should be inhibited during enzymatic depilation. Caseinase and collagenase were isolated and purified to homogeneity from commercial bacillus subtilis AS1.398 by affinity chromatography on the basis of modified hide powder as supporter. The purified enzyme had estimated molecular mass 44.3kDa determined by SDS-PAGE. Assays were also made on the activities of the two proteases. The specific activity of the caseinase showed a recovery of 42 %. En ligne : https://drive.google.com/file/d/1CNu0AWG_OtPsi3baQseZT99KQV-tfQkh/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=4079
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 93, N° 1 (01-02/2009) . - p. 8-11[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 011127 - Périodique Bibliothèque principale Documentaires Disponible Low pressure ion chromatography in complex chemistry in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 85, N° 1 (01-02/2001)
[article]
Titre : Low pressure ion chromatography in complex chemistry Type de document : texte imprimé Année de publication : 2001 Article en page(s) : p. 16-18 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Chimie analytique
Chromatographie
Solutions (chimie)
Sulfate d'aluminium
Sulfate de chrome
Tannage minéralTannage dans lequel interviennent différents minéraux. Le plus répandu est le tannage aux sels de chrome, mais aussi à l’aluminiumIndex. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Basic chromium sulphate and basic aluminium sulphate solutions are the principal tanning liquors in the leather-making industry. In order to improve the qualities of the resultant leather and to do further research on leather-making mechanisms, it is necessary to explore the composition and charges of the above two complex compounds, which also helps research into the theories of complex chemistry. Basic chromium sulphate and basic aluminium sulphate solutions have been separated with columns such as Dowex 50, Zerolite and Sephadex C25. Low pressure ion chromatography (LPIC), was first applied to separate complex compounds and excellent results were obtained. LPIC has such advantages as fast separation, high sensitivity, excellent separation performance and simple operation. Note de contenu : - EXPERIMENTAL : Apparatus - Reagents - 114am chromatographic conditions - Preparation of mixed solution of the complex compound - Separation and determination of the complex compounds - Determination of cr3 A /3 + and SO in cad component
- RESULTS AND DISCUSSION : choice of the separation column - Choice of the elution system - Separation and analysis of the mixed solution of Cr(OH) SO4 and Al(OH SO4 - Separation results of GFC - Application characteristics of LPIC in the separation and determination of complex compounds
- Table 1 : Chromatographic conditions
- Table 2 : Determination results of Cr 3,AI and SO in the mixed solution of basic chromium and aluminium saltsEn ligne : https://drive.google.com/file/d/1K9WfwOft3_UeOvyXDWaEuvL0fc4ASe4u/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=40589
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 85, N° 1 (01-02/2001) . - p. 16-18[article]Modern analysis methods analysis methods for polyolefin compounds in ADHESION - ADHESIVES + SEALANTS, Vol. 18, N° 1/2021 (2021)
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