[article]
Titre : |
Negative effects of haloversatile bacteria in salt on skins and their control with direct electric current in the leather industry |
Type de document : |
texte imprimé |
Auteurs : |
Haider Sabah Abdulhusein, Auteur ; Pinar Caglayan, Auteur ; Meral Birbir, Auteur ; Yasar Birbir, Auteur |
Année de publication : |
2023 |
Article en page(s) : |
p. 207-214 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Bactéries haloversatiles Courants continus Cuirs et peaux -- Conservation Cuirs et peaux de chèvres Cuirs et peaux de moutons Microbiologie Sels de sodium
|
Index. décimale : |
675 Technologie du cuir et de la fourrure |
Résumé : |
The salt preservation method has been used for a long time in the leather industries with salt applied to raw skins and hides in order to control bacterial activity and to remove the moisture found in the skin structure. It is known that the salt used in curing process contains many halophilic bacterial species.
During the salting process, skins and hides might be contaminated with these micro-organisms. The goal of this research was to determine factors including the pH of salt samples, total count of haloversatile bacteria, proteolytic haloversatile bacteria, and lipolytic haloversatile bacteria found in these samples and to isolate, and identify haloversatile bacteria from the salt samples, to test their ability to use various amino acid and sugar sources, to characterise their enzymatic properties, to investigate their adverse effects on sheepskinand goatskin samples using a scanning electron microscopy. In addition, 2.5A direct electric current was applied against mixed culture of enzyme-producing haloversatile bacteria in 15% NaCl solution to search for an alternative environmentally friendly preservation method for skin/hide curing. The pH values of salt samples were found to be between 7.60 and 8.04.
The total counts of haloversatile bacteria, proteolytic haloversatile bacteria and lipolytic haloversatile bacteria were found to be 6 × 103CFU/g to 1.3 × 105CFU/g; 1×103-7×103CFU/g and 1.4 × 103-3.1 × 104CFU/g, respectively. 35 haloversatile bacteria belonging to ten different genera (Staphylococcus, Corynebacterium, Peribacillus, Lysinibacillus, Kocuria, Paenibacillus, Bhargavaea, Bacillus, Pseudomonas and Micrococcus) were isolated and identified from the salt samples.
The ability of haloversatile bacteria to use sugars and amino acids varied from one genus to another genus. While catalase, esterase, urease, protease, caseinase, lipase, xylanase, cellulase, amylase, DNase and oxidase enzymes were produced among the isolates, pullulanase enzyme was not produced. The scanning electron microscope micrographs showed that enzyme-producing haloversatile bacteria had significant effects on goatskin and sheepskin. The total number of the mixed culture was reduced from 3.6 × 106CFU/mL to 4×101CFU/mL within 17 minutes, and all cells were completely killed within 21 minutes.
The scanning electron micrographs showed that the structure and the organoleptic characterictics of bacteria treated sheepskin and goatskin samples were negatively changed at the end of 40-days storage. |
Note de contenu : |
- Salt sample collection and measuring pH value of salt samples
- Determination of the total numbers of haloversatile bacteria in the salt samples
- Determination of the total numbers of proteolytic and lipolytic haloversatile bacteria in salt samples
- Isolation of haloversatile bacteria
- Identification of haloversatile isolates according to 16S rRNA gene sequence analyses
- Nucleotide accession number
- Effects of different NaCl concentrations, pH values and temperature on haloversatile bacterial growth
- Investigation of enzymatic properties of haloversatile bacteria
- Utilisation of different amino acids and different carbon sources by haloversatile bacteria
- Investigation the effects of the mixed culture of enzyme producing haloversatile isolates on sheepskin and goatskin
- Extermination of haloversatile bacteria by direct electric current
- Investigation of the bacterial cells before and after the treatment with direct electric current by scanning electron microscopy
- Table 1 : The pH values, total counts of haloversatile bacteria, proteolytic haloversatile bacteria and lipolytic haloversatile bacteria in the salt samples
- Table 2 : The effects of pH, NaCl contents and temperature values on bacterial growth
- Table 3 : Enzymatic properties of haloversatile bacterial isolates
- Table 4 : Utilization of different amino acids by haloversatile isolates
- Table 5 : Utilisation of different sugars by haloversatile isolates
- Table 6 : The pH values, temperature and the total counts (CFU/mL) of enzyme producing haloversatile bacteria in the direct electric current treatment |
En ligne : |
https://drive.google.com/file/d/1qRfWv_CwzI3WQkn8QhrK0n0Rq2zPAjwb/view?usp=drive [...] |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=40239 |
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 107, N° 6 (11-12/2023) . - p. 207-214
[article]
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