Extensive screening for a robust producer of α-L-rhamnosidase activity from well-defined strains of filamentous fungi, including multifactorial optimization (inducers, cultivation conditions) was accomplished. Enzyme production of the optimal producer Aspergillus terreus (non-toxigenic) was scaled up to 50L. α-L-Rhamnosidase, which was fully characterized, proved to be thermo- and alkali-tolerant, thus enabling effective operation at 70°C and pH 8.0. These conditions allow for a very high substrate (rutin) load up to 100-300 g/L, thus enabling very high volumetric productivity of the reaction product quercetin-3-β-D-glucopyranoside (isoquercitrin). Here, a novel concept of "immobilised substrate" is used. Isoquercitrin is a highly effective and biocompatible antioxidant with strong anti-inflammatory activities. Rutin biotransformation was optimized and scaled up to ca 10 kg production and thus the robustness of the large-scale production was demonstrated. Isoquercitrin can be produced to a very high purity (98%) in multikilogram amounts, without any quercetin and directly applicable in nutraceuticals.
- MeSH
- alkálie farmakologie MeSH
- Aspergillus účinky léků enzymologie MeSH
- beta-glukosidasa metabolismus MeSH
- bioreaktory mikrobiologie MeSH
- biotechnologie metody MeSH
- biotransformace účinky léků MeSH
- fyziologická adaptace účinky léků MeSH
- glukosidy biosyntéza chemie MeSH
- glykosidhydrolasy metabolismus MeSH
- koncentrace vodíkových iontů účinky léků MeSH
- quercetin analogy a deriváty biosyntéza chemie MeSH
- rutin chemie metabolismus MeSH
- stabilita enzymů účinky léků MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A number of biologically active natural products are glycosides. Often, the glycosidic residue is crucial for their activity. In other cases, glycosylation only improves their pharmacokinetic parameters. Enzymatic modification of these glycosides - both extension of the glycoside moiety and its selective trimming - is advantageous due to their selectivity and mildness of the reaction conditions in the presence of reactive and sensitive complex aglycones. Enzymatic reactions enable the resulting products to be used as "natural products", e.g., in nutraceuticals. This chapter concentrates on naturally occurring glycosides used in medicine but also in the food and flavor industry (e.g., sweeteners). Both "classical" and modern methods will be discussed.
- MeSH
- Aspergillus MeSH
- biotransformace MeSH
- galaktosidasy MeSH
- Penicillium MeSH
- Publikační typ
- kongresy MeSH
