In this study yeast cell physiological activity was assessed on the basis of the in situ activity of two important enzymes, succinate dehydrogenase and pyruvate decarboxylase. FUN1 dye bioconversion and cellular ATP content were also taken as important indicators of yeast cell activity. The study was conducted on six brewing yeast strains, which were either free cells or immobilized on a chamotte carrier. The experimental data obtained indicate clearly that, in most cases, the immobilized cells showed lower enzyme activity than free cells from analogous cultures. Pyruvate decarboxylase activity in immobilized cells was higher than in planktonic cell populations only in the case of the Saccharomyces pastorianus 680 strain. However, in a comparative assessment of the fermentation process, conducted with the use of free and immobilized cells, much more favorable dynamics and carbon dioxide productivity were observed in immobilized cells, especially in the case of brewing lager yeast strains. This may explain the higher total cell density per volume unit of the fermented medium and the improved resistance of immobilized cells to environmental changes.
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http://dx.doi.org/10.1007/s10482-013-9978-1 | DOI Listing |
Microorganisms
December 2024
Biosensor Research Institute, Seoul National University of Science & Technology, Seoul 01811, Republic of Korea.
The WHO has classified Helicobacter pylori as a group 1 carcinogen for stomach cancer since early 1994. However, despite the high prevalence of Helicobacter pylori infection, only about 3% of infected people eventually develop gastric cancer.Biomolecular detections of Helicobacter pylori(HP) were compared using specially modified sensors and fluorine immobilized on a carbon nanotube (HFCNT) electrode, which yielded sensitive results.
View Article and Find Full Text PDFFoods
December 2024
Laboratory of Applied Microbiology and Biotechnology, Department of Molecular Biology and Genetics, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece.
The aim of this study was to examine the effect of free or immobilized OLXAL-1 cells on oat flakes on the gut microbiota and metabolic and inflammatory markers in a streptozotocin (STZ)-induced Type-1 Diabetes Mellitus (T1DM) animal model. Forty-eight male Wistar rats were assigned into eight groups (n = 6): healthy or diabetic animals that received either a control diet (CD and DCD), an oat-supplemented diet (OD and DOD), a diet supplemented with free OLXAL-1 cells (CFC and DFC), or a diet supplemented with immobilized OLXAL-1 cells on oat flakes (CIC and DIC). Neither OLXAL-1 nor oat supplementation led to any significant positive effects on body weight, insulin levels, plasma glucose concentrations, or lipid profile parameters.
View Article and Find Full Text PDFInt Immunopharmacol
January 2025
AT-31 BIO Inc., 403 Business Incubation Center, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea; Laboratory of Immunobiology, School of Life Science and Biotechnology, College of Natural Sciences, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea. Electronic address:
Recombinant GH16B β-agarase-catalyzed liquefaction of 5-7 %(w/v) melted agarose at 50 °C completely hydrolyzed agarose into neoagarohexaose (NA6) and neoagarotetraose (NA4). Subsequent saccharification by recombinant GH50A β-agarase or recombinant GH50A β-agarase/recombinant GH117A α-neoagarobiose hydrolase at 35 °C converted NA6/NA4 into neoagarobiose (NA2) or 3,6-anhydro-L-galactose (L-AHG)/D-galactose, respectively. Purification of NA6/NA4 and NA2 was achieved by Sephadex G-15 column chromatography, while L-AHG was purified by Sephadex G-10, achieving ≥ 98 % purity.
View Article and Find Full Text PDFLangmuir
January 2025
Perm State University, 15 Bukirev strasse, Perm 614068, Russia.
Copper(II) oxide nanoparticles (CuO NPs) are used in different industries and agriculture, thus leading to their release to the environment, which raises concerns about their ecotoxicity and biosafety. The main toxicity mechanism of nanometals is oxidative stress as a result of the formation of reactive oxygen species caused by metal ions released from nanoparticles. Bacterial biofilms are more resistant to physical and chemical factors than are planktonic cells due to the extracellular polymeric matrix (EPM), which performs a protective function.
View Article and Find Full Text PDFHybrid Adv
December 2024
Department of Environmental Studies, Visva-Bharati, Santiniketan 731235, West Bengal, India.
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