Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleAçık Erişim2019Scopus SJRQ3
    Presence of different bacterial species in thermal sources and novelty in their industrial enzyme productions

    Albayrak, Seyda; Genc, Berna; Ozkan, Hakan; Taskin, Mesut; Adiguzel, Ahmet

    In this study, one hundred and thirty isolates were isolated from water and sludge samples taken from hot springs located in different regions of Turkey. Among them, eleven isolates were chosen according to conventional (morphological, physiological and biochemical tests) and molecular methods (rep-PCR and 16S rRNA sequencing). These bacteria were then tested for their capability to produce valuable enzymes. As a result; species belonging to Bacillus, Anoxybacillus, Aeribacillus, Enterococcus, Exiguobacterium and Paenibacillus were identified. Test strains were found to have optimum reproductive potential at pH 5.0-9.0 and 15-65°C, usually at a concentration of 1.0-10.0% (w/v) NaCl. In addition, all thermotolerant bacteria were Gram, endospore (except E. profundum), catalase and oxidase (except E. faecium and E. profundum) positive, and rod-shaped (except E. faecium). It was observed that all isolates had a 99% similarity percentage as a result of 16S rRNA sequence analysis. All of the isolates were capable of producing industrially important enzymes moreover, eight of them could produce at least two of these enzymes. Test strains had high potential of industrial enzyme production, and the enzymes from these thermo-tolerant isolates will be widely used in biotechnological processes.

    AtıfScopus7WoS7OpenAlex7
    İncele
  • MakaleYalnız künye2011Scopus SJRQ1
    Determination of Lactic Microflora of Kefir Grains and Kefir Beverage by Using Culture-Dependent and Culture-Independent Methods

    Kesmen, Zulal; Kacmaz, Nazife

    In this study, we investigated the bacterial compositions of kefir grains and kefir beverages collected from different regions of Turkey by using culture-independent and culture-dependent methods. In the culture-independent detection, 10 different species of bacteria were detected in total by using the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis of the 16S rRNA gene V3 region. Among these species, Lactobacillus kefiranofaciens was the most dominant one in the kefir grains, while Lactococcus lactis was found to be significantly prevalent in the kefir beverages. In the culture-dependent detection, the primary differentiation and grouping of the isolates from kefir beverages and kefir grains were performed using repetitive sequence-based PCR (rep-PCR) fingerprinting, and the results were validated by 16S rDNA full-length sequencing. According to the results of culture-dependent methods, the most frequently isolated species were L. lactis, Leuconostoc mesenteroides, and Lactobacillus kefiri, respectively. Only 3 species, which are L. lactis, Lactobacillus acidophilus, and Streptococcus thermophilus, were detected with both culture-dependent and culture-independent methods. This study showed that the combination of both methods is necessary for a detailed and reliable investigation of microbial communities in kefir grains and kefir beverages. Practical Application Due to their artisan- and region-dependent microflora, kefir products can be a source of interesting lactic acid bacteria, either new taxa or strains with specific functional properties, which might be used for the development of new starter cultures and innovative food products. Therefore, an increasing demand exists for new strains that show desirable effects on the product characteristics Artisan dairy products are a candidate source of such microorganisms. For this reason, in this study, the bacterial compositions of kefir grains and kefir beverages obtained from different regions of Turkey were studied using culture-dependent and culture-independent molecular methods.

    • SDG 2 · Açlığa Son
    AtıfWoS86OpenAlex104
    İncele