Combining high-carbohydrate food with polyphenol-rich food is a possible way of producing slowly digestible starch with beneficial health properties. In Japan, non-glutinous and glutinous rice are cooked with adzuki bean and the colour of the cooked rice is pale red. In this article, we show that (1) the red colour of rice could be attributed to the oxidation of adzuki bean procyanidins, (2) pancreatin-induced starch digestion of the red-coloured non-glutinous rice was slower than white rice and (3) the digestion of amylose and potato starch but not amylopectin became slower by heating with procyanidin B2. Furthermore, the rate of starch digestion of red-coloured rice was not affected by nitrite treatment under simulated gastric conditions. The above results show that procyanidins could bind to amylose independent of the starch source by heating and could suppress starch digestion by α-amylase in the intestine.

• MeSH
• alfa-amylasy MeSH
• amylopektin metabolismus   MeSH
• amylosa metabolismus   MeSH
• biflavonoidy MeSH
• katechin MeSH
• lidé MeSH
• pankreatin metabolismus   MeSH
• proantokyanidiny metabolismus   MeSH
• rýže (rod) * MeSH
• trávení * MeSH
• vaření MeSH
• vigna * MeSH
• vysoká teplota MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Japonsko MeSH

An extracellular amylase secreted by Aspergillus niveus was purified using DEAE fractogel ion exchange chromatography and Sephacryl S-200 gel filtration. The purified protein migrated as a single band in 5 % polyacrylamide gel electrophoresis (PAGE) and 10 % sodium dodecyl sulfate (SDS-PAGE). The enzyme exhibited 4.5 % carbohydrate content, 6.6 isoelectric point, and 60 and 52 kDa molar mass estimated by SDS-PAGE and Bio-Sil-Sec-400 gel filtration column, respectively. The amylase efficiently hydrolyzed glycogen, amylose, and amylopectin. The end-products formed after 24 h of starch hydrolysis, analyzed by thin layer chromatography, were maltose, maltotriose, maltotetraose, and maltopentaose, which classified the studied amylase as an α-amylase. Thermal stability of the α-amylase was improved by covalent immobilization on glyoxyl agarose (half-life of 169 min, at 70 °C). On the other hand, the free α-amylase showed a half-life of 20 min at the same temperature. The optima of pH and temperature were 6.0 and 65 °C for both free and immobilized forms.

• MeSH
• alfa-amylasy izolace a purifikace   metabolismus   MeSH
• amylopektin metabolismus   MeSH
• amylosa metabolismus   MeSH
• Aspergillus enzymologie   MeSH
• chromatografie iontoměničová MeSH
• chromatografie na tenké vrstvě MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• enzymy imobilizované chemie   metabolismus   MeSH
• gelová chromatografie MeSH
• glykogen metabolismus   MeSH
• hydrolýza MeSH
• koncentrace vodíkových iontů MeSH
• molekulární sekvence - údaje MeSH
• sekvence aminokyselin MeSH
• sekvenční seřazení MeSH
• stabilita enzymů MeSH
• teplota MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

It is generally accepted that dead tree decomposition is performed mainly by delignifying basidiomycetes. While ascomycetes have been reported to inhabit dead tree bark, their contribution to dead tree decomposition is still unclear. Here, we isolated five bark-inhabiting ascomycetes possessing cellulolytic activity from dead beech tree and assessed their polysaccharolytic activities. When cultivated in a medium containing filter paper as a sole carbon source, three strains degraded >40 % of the filter paper in a 4-week cultivation and the others degraded 15-30 % of the paper. The degraders possessed amylolytic, pectinolytic, and mannanolytic activities as well as cellulolytic activity, implying that they play an important role in dead tree decomposition after delignification by basidiomycetes. Phylogenetic analysis based on large subunit ribosomal DNA (lsu-DNA) sequences implied that the isolates belonged to Penicillium or Amorphotheca.

• MeSH
• amylosa metabolismus   MeSH
• Ascomycota izolace a purifikace   klasifikace   metabolismus   MeSH
• buk (rod) mikrobiologie   MeSH
• celulosa metabolismus   MeSH
• DNA fungální genetika   chemie   MeSH
• financování organizované MeSH
• fungální RNA genetika   MeSH
• geny rRNA MeSH
• kultivační média chemie   MeSH
• mannany metabolismus   MeSH
• mikrobiologie životního prostředí MeSH
• papír MeSH
• pektiny metabolismus   MeSH
• ribozomální DNA genetika   chemie   MeSH
• RNA ribozomální genetika   MeSH
• sekvenční analýza DNA MeSH