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Extracellular protease activities of extremely halophilic archaea and their control via direct electric current / Meral Birbir in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 92, N° 2 (03-04/2008)
[article]
Titre : Extracellular protease activities of extremely halophilic archaea and their control via direct electric current Type de document : texte imprimé Auteurs : Meral Birbir, Auteur ; Z. B. Ozdogru, Auteur ; Yasar Birbir, Auteur ; Ayse Ogan, Auteur Année de publication : 2008 Article en page(s) : p. 53-58 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Bactéries halophiles
Bain de saumure
Courants continus
Cuirs et peaux -- Conservation
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.
Microbiologie
PeptidasesIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : Proteolytic enzymes which are produced by extremely halophilic Archaea present in salt may cause serious damage on salted hides and may result in significant economic losses in the leather industry. Hence, protease activities of 24 protease producing extremely halophilic archaeal strains isolated from Tuz Lake, Kaldırım and Kayacık salterns and Tuzköy salt mine were determined in this study. The protease activities of Tuz Lake, Kaldırım saltern, Kayacık saltern and Tuzköy salt mine strains were found as between 80.0 and 83.3, 81.1 and 83.8, 83.3 and 83.4, 82.0 and 83.4 Units, respectively. To prevent proteolytic haloarchaeal damage on brine cured hides, the protease producing strains were treated with 0.5A direct electric current for 20min. Although proteolytic strains of Tuz Lake and Tuzköy salt mine in the liquid gelatin media were killed by 0.5A direct electric current within 15min, 10min direct electric current treatment were enough to kill all proteolytic strains of Kaldırım and Kayacık salterns. Also, the effect of 0.5A direct electric current on protease activities of the test strains was examined during 20min treatment in this study. It was found that 0.5A direct electric current caused a slight decrease on protease activities of the test strains. Therefore, it is necessary to kill protease producing strains in brine solution with direct electric current before the excretion of their protease into the brine solution. Note de contenu :
- Extremely halophilic strain
- Protease activities of the extremely halophilic strains
- Inactivation of the test strains with 0.5A direct electric current
- Table 1 : Protease activities of extremely halophilic Archaea isolated from Tuz Lake, Kaldırım and Kayacık Salterns and Tuzköy Salt Mine
- Table 2 : Voltage, temperature and rf values of 4 mixed proteolytic halophilic Archaea inactivated in the liquid gelatin media by 0.5A direct electric current within 20 minutes
- Table 3 : The effect of 0.5A direct electric current on protease activities of some of the test strains during 20 minutes treatmentEn ligne : https://drive.google.com/file/d/1gBbMoBdjmpLA6cnCaGdQjxhmAhOnxKZz/view?usp=share [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38930
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 92, N° 2 (03-04/2008) . - p. 53-58[article]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]
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 -- SalageIndex. 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 antibioticsEn ligne : https://drive.google.com/file/d/1-JnbM3mZR_C5Q694HQuVebsBc0QBWPb5/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39635
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 3 (05-06/2004) . - p. 99-104[article]The effects of alternating and direct electric currents on moderately halohilic bacteria in leather industry / Pinar Caglayan in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 100, N° 6 (11-12/2016)
[article]
Titre : The effects of alternating and direct electric currents on moderately halohilic bacteria in leather industry Type de document : texte imprimé Auteurs : Pinar Caglayan, Auteur ; Meral Birbir, Auteur ; Ayse Ogan, Auteur ; Antonio Ventosa, Auteur ; Cristina Sánchez-Porro, Auteur ; Yasar Birbir, Auteur Année de publication : 2016 Article en page(s) : p. 307-313 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Antimicrobiens
Bactéries -- Inactivation
Courants électriques
Cuirs et peaux -- Conservation
Cuirs et peaux de moutonsIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : Proteolytic and lipolytic moderately halophilic bacteria, originate from salt, may be found on salted sheep skins. Microbial spoilage of sheepskin usually result a from the failure to inactivate proteolytic and Iipolytic micro-organisms during skin preservation. To solve this problem, an effective inactivation method to be used in the leather industry was examined in this study. Protease and lipase activities of moderately halophilic Staphylococcus saprophyticus subsp. saprophyticus (TR5), Bacilius pumilus (DB5), Bacillus licheniformis (DBA2), Gracilibacillus dipsosauri (EK2) and Idiomarina loihiensis (GA3), isolated from salted sheepskins, were examined : Protease activity of each test isolate was determined by bath gelatin agar medium and casein digestion assay at 280nm. Lipolytic activity of each test isolate was determined by bath Tween 80 agar medium and measuring hydrolysis of p-nitrophenylbutyrate to p-nitrophenol at 405nm. Antibiotic sensitivities of test isolates to novobiocin, penicillin G, tetracycline, streptomycin, erythromycin, tobramycin, kanamycin and gentamicin were tested using disc diffusion susceptibility method. These isolates were found to be proteolytic, lipolytic and resistant to aforementioned antibiotics. inactivation effects of direct electric currents and alternating electric currents (0.5A, 1.0A, 1: 5A and 2.0A) on the mixed culture of these isolates were separately examined in liquid medium containing 25% NaCl. The mixed culture was killed in 1 minute by 0.5A direct current and 1.5A affernating current treatments. However, 0.5A alternating current and 1.0A alternating current treatments eliminated these micro-organisms respectively in 15 minutes and 10 minutes. In conclusion, electric current applications hold great potentiel for the eradication of proteolytic and lipolytic, antibiotic-resistant, moderately halophilic bacteria in leather industry. Note de contenu : - EXPERIMENTAL PROCEDURES : Moderately halophilic bacterial isolates - Proteolytic and lipolytic activities of moderately halophilic bacteria - Antimicrobial susceptibility test - The electrochemical treatment system
- RESULTS AND DISCUSSION : Antibiotic resistanceEn ligne : https://drive.google.com/file/d/1694CJoD9Uwle2gArKMHAUoJyAkxmVqSI/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=27666
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 100, N° 6 (11-12/2016) . - p. 307-313[article]Réservation
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