Mechanisms of inactivation of Candida humilis and Saccharomyces cerevisiae by pulsed electric fields
| Autor: | Marija Nikolic-Jaric, Michael G. Gänzle, Qi-Xing Ou |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0106 biological sciences
Cell Membrane Permeability Saccharomyces cerevisiae Biophysics 01 natural sciences Microbiology chemistry.chemical_compound Electromagnetic Fields 0404 agricultural biotechnology Potassium phosphate 010608 biotechnology Electric field Electrochemistry Specific energy Propidium iodide Physical and Theoretical Chemistry Candida humilis Candida biology Pulse (signal processing) Equipment Design 04 agricultural and veterinary sciences General Medicine biology.organism_classification 040401 food science Electroporation chemistry Electrode Propidium |
| Zdroj: | Bioelectrochemistry. 115:47-55 |
| ISSN: | 1567-5394 |
| DOI: | 10.1016/j.bioelechem.2016.12.005 |
| Popis: | Aims This study aimed to determine how electric field strength, pulse width and shape, and specific energy input relate to the effect of pulsed electric fields (PEF) on viability and membrane permeabilization in Candida humilis and Saccharomyces cerevisiae suspended in potassium phosphate buffer. Methods and results Cells were treated with a micro-scale system with parallel plate electrodes. Propidium iodide was added before or after treatments to differentiate between reversible and irreversible membrane permeabilization. Treatments of C. humilis with 71 kV/cm and 48 kJ/kg reduced cell counts by 3.9 ± 0.6 log (cfu/mL). Pulse shape or width had only a small influence on the treatment lethality. Variation of electric field strength (17–71 kV/cm), pulse width (0.086–4 μs), and specific energy input (8–46 kJ/kg) demonstrated that specific energy input correlated to the membrane permeabilization (r2 = 0.84), while other parameters were uncorrelated. A minimum energy input of 3 and 12 kJ/kg was required to achieve reversible membrane permeabilization and a reduction of cell counts, respectively, of C. humilis. Conclusions Energy input was the parameter that best described the inactivation efficiency of PEF. Significance and impact of study This study is an important step to identify key process parameters and to facilitate process design for improved cost-effectiveness of commercial PEF treatment. |
| Databáze: | OpenAIRE |
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