OBJECTIVES: To improve the storage stability and reusability of various yeast strains and species by immobilization in polyvinyl alcohol (PVA) hydrogel particles. RESULTS: Debaryomyces hansenii, Pichia sorbitophila, Saccharomyces cerevisiae, Yarrowia lipolytica, and Zygosaccharomyces rouxii were immobilized in PVA particles using LentiKats technology and stored in sterile water at 4 °C. The immobilization improved the survival of all species; however, the highest storage stability was achieved for S. cerevisiae and Y. lipolytica which survived more than 1 year, in contrast to free cells that survived for only 3 months. Tests of the reusability of immobilized recombinant laccase-secreting S. cerevisiae revealed that the cells were suitable for repetitive use (55 cycles during 15 months) even after storage in water at 4 °C for 9 months. A suitable method for killing immobilized laccase-secreting cells without affecting the produced enzyme activity was also developed. CONCLUSIONS: The immobilization of yeasts in PVA hydrogel enables long-term, cheap storage with very good cell viability and productivity, thus becoming a promising approach for industrial applications.
- MeSH
- biotechnologie MeSH
- buněčné kultury MeSH
- imobilizované buňky * cytologie enzymologie metabolismus MeSH
- lakasa chemie metabolismus MeSH
- mikrobiální viabilita MeSH
- ochrana biologická metody MeSH
- opakované použití vybavení MeSH
- polyvinylalkohol chemie MeSH
- rekombinantní proteiny chemie metabolismus MeSH
- Saccharomyces cerevisiae * cytologie enzymologie metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
The aims of the present study were to isolate new yeasts with high extracellular (exo) invertase activity and to investigate the usability of buffer systems as invertase production media by immobilized yeast cells. Among 70 yeast isolates, Cryptococcus laurentii MT-61 had the highest exo-invertase activity. Immobilization of yeast cells was performed using sodium alginate. Higher exo-invertase activity for immobilized cells was achieved in tris-sucrose buffer system (TSBS) compared to sodium acetate buffer system and potassium phosphate buffer system. TSBS was prepared by dissolving 30 g of sucrose in 1 L of tris buffer solution. The optimum pH, temperature, and incubation time for invertase production with immobilized cells were determined as 8.0, 35 °C and 36 h in TSBS, respectively. Under optimized conditions, maximum exo-invertase activity was found to be 28.4 U/mL in sterile and nonsterile TSBS. Immobilized cells could be reused in 14 and 12 successive cycles in sterile and nonsterile TSBS without any loss in the maximum invertase activity, respectively. This is the first report which showed that immobilized microbial cells could be used as a biocatalyst for exo-invertase production in buffer system. As an additional contribution, a new yeast strain with high invertase activity was isolated.
- MeSH
- biotechnologie metody MeSH
- časové faktory MeSH
- Cryptococcus enzymologie metabolismus MeSH
- imobilizované buňky enzymologie metabolismus MeSH
- invertasa izolace a purifikace MeSH
- koncentrace vodíkových iontů MeSH
- kultivační média chemie MeSH
- pufry MeSH
- sacharosa MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- enzymy imobilizované chemie metabolismus MeSH
- Escherichia coli enzymologie genetika MeSH
- finanční podpora výzkumu jako téma MeSH
- imobilizované buňky enzymologie MeSH
- kyselina cytidinmonofosfát-N-acetylneuraminová metabolismus MeSH
- lyasy oxokyselin MeSH
- oxid křemičitý MeSH
- pektiny chemie MeSH
- Publikační typ
- srovnávací studie MeSH
Suspenzné kultúry maku siateho (Papaver somniferum L.) sa permeabilizovali Tweenom 80 a imo- bilizovali glutaraldehydom. pH optimum invertázy v imobilizovaných bunkách je 4,6 a tepelné optimum je pri 50 °C. Enzýmová reakcia má lineárny priebeh 5 hodín a dosahuje 69 % konverzie. Imobilizované bunky majú vysokú invertázovú aktivitu a výhodné mechanické vlastnosti.
Cell suspension culture of the opium poppy plant (Papaver somniferum L.) was permeabilized by Tween 80 and immobilized by glutaraldehyde. The pH optimum of the immobilized cells' invertase is 4.6 and the temperature optimum is 50 °C. The enzyme hydrolysis was linear for 5 h, reaching 69 % of conversion. The immobilized cells are characterized by a high invertase activity and showed convenient mechanical properties.
