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- MakaleYalnız künye2018New xylanolytic enzyme from Geobacillus galactosidasius BS61 from a geothermal resource in Turkey
Sari, Bilge; Faiz, Ozlem; Genc, Berna; Sisecioglu, Melda; Adiguzel, Ahmet; Adiguzel, Gulsah
In this study, isolation, conventional and molecular characterizations of ten thermophilic bacteria from Rize/Ayder were carried out. Xylanase from Geobacillus galactosidasius BS61 (GenBank number: KX447660) was purified by acetone precipitation, Diethylaminoethyl-cellulose and Sephadex G-100 chromatographies. The xylanase of G. galactosidasius BS61 in clarifying fruit juice was also investigated. Enzyme was purified 29.80-fold with 75.18% yield; and molecular weight was determined as 78.15 kDa. The optimum temperature of xylanase was 60 °C. The enzyme activity was maintained fully after 24 h and over 50% after 168 h at pH 4.0–10.0, while optimum pH was 7.0. Km and Vmax for beech wood xylan were measured as 3.18 mg mL−1, 123 U mg protein−1. In addition, Ca2+, Na+, Al3+, Zn2+, Cd2+, Mg2+, Ni2+, Cu2+ had decreasing effect on enzyme activity, while enzyme activity had been protected against anions, especially HSO3− and HPO4 2− stimulated enzyme activity. Xylanase applications (with 15 U/mL enzyme activity) in orange and pomegranate juices were increased; and the sugar and turbidity amounts were reduced 17.36% ± 1.18 and 30.52 ± 1.23, respectively. These results indicated that the xylanase of G. galactosidasius BS61 has biotechnological potential in juice clarification due to its stability against metal ions, chemicals and high pH-values.
- MakaleYalnız künye2017Isolation and Characterization of Thermophilic Bacteria from Geothermal Areas in Turkey and Preliminary Research on Biotechnologically Important Enzyme Production
Baltaci, Mustafa Ozkan; Genc, Berna; Arslan, Sumeyya; Adiguzel, Gulsah; Adiguzel, Ahmet
In this study, the isolation, identification and characterization of the thermophilic bacteria from different hot springs in Turkey were carried out by conventional (morphological, physiological and biochemical tests) and molecular methods (fatty acid methyl esters, GTG5-PCR and 16S rRNA sequencing). These thermophilic bacteria were then tested for their capability to produce enzymes such as lipase, protease, amylase and cellulase. O20 strain is a novel species according to identification studies. All of its isolates were capable of producing industrially valuable enzymes based on screening. In fact, most of them could produce at least two of these enzymes.
- MakaleYalnız künye2015Purification and characterization of an extracellular cellulase from Anoxybacillus gonensis O9 isolated from geothermal area in Turkey
Genc, Berna; Nadaroglu, Hayrunnisa; Adiguzel, Ahmet; Baltaci, Ozkan
In the present study, cellulase was purified and characterized from Anoxybacillus gonensis (Gen bank Number: KM596794) which was isolated and characterized from Agri Diyadin Hot spring. It was found to synthesize cellulase which had a wide range of industrial applications. Twenty four-hour-cultured bacteria induced cellulase production and specific activities during the purification steps were 1.47,81.06 and 109.4 EU mg-1 protein at crude extract, ammonium sulphate precipitated and DEAE-Sephadex purification steps. The highest enzyme activity was observed at 50°C and the optimum range of pH was 3-10. Molecular weight of enzyme was determined approximately 40kDa. The kinetic parameters of cellulase against carboxymethylcellulose (CMC) were 153.4 μmol min-1 mg for Vmax and 0.46mM for Km. Among effectors of the enzyme, Zn2+, Ca2+, Co2+ and EDTA decreased enzyme activity.