Publications by authors named "Dey-Chyi Sheu"

Neokestose has superior prebiotic effects compared with the commercial fructooligosaccharides (FOS). In addition, the branched structure of neokestose, a type of neo‑FOS, confers improved chemical stability compared with conventional FOS; therefore, the investigation of the branched structure by the present study may be of high biomedical value. The present study aimed to determine whether neokestose may suppress growth of the A2058 melanoma cell line.

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Neokestose is a 6G-fructooligosaccharide (FOS) and an important prebiotic. When FOS are ingested by patients with colorectal cancer, they may come into contact with cancer cells prior to being fermented by bifidobacteria in the colon. In the present study, the effects of neokestose on cell proliferation, cell cycle and apoptosis of the colorectal cancer cell line Caco-2 were investigated to evaluate its anti-cancer effect.

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Peroxiredoxins (Prxs) play important roles in antioxidant defense and redox signaling pathways. A Prx isozyme cDNA (TcPrx2, 745 bp, EF552425) was cloned from Taiwanofungus camphorata and its recombinant protein was overexpressed. The purified protein was shown to exist predominantly as a dimer by sodium dodecyl sulfate-polyacrylamide gel electrolysis in the absence of a reducing agent.

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High-purity fructooligosaccharides (FOS) were produced from sucrose by an innovative process incorporating immobilized Aspergillus japonicus and Pichia heimii cells. Intracellular FTase of A. japonicus converted sucrose into FOS and glucose, and P.

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Neofructooligosaccharides (neo-FOS) were produced in submerged cultures of Xanthophyllomyces dendrorhous. Among the various strains of X. dendrorhous that have intracellular (6)G-fructofuranosidase ((6)G-FFase), BCRC 21346 with high enzyme activity (3.

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Aim: To enhance the differentiation of insulin producing cell (IPC) ability from embryonic stem (ES) cells in vitro.

Methods: Four-day embryoid body (EB)-formatted ES cells were dissociated as single cells for the followed plasmid DNA delivery. The use of Nucleofector electroporator (Amaxa biosystems, Germany) in combination with medium-contained G418 provided a high efficiency of gene delivery for advanced selection.

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Of three beta-galactosidases from Aspergillus oryzae, Kluyveromyces lactis and Bacillus sp., used for the production of low-content galacto- oligosaccharides (GOS) from lactose, the latter produced the highest yield of trisaccharides and tetrasaccharides. GOS production was enhanced by mixing beta-galactosidase glucose oxidase.

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A partially purified beta-fructofuranosidase from Aspergillus japonicus was covalently immobilized on to chitosan beads using either glutaraldehyde or tris(hydroxymethyl)phosphine (THP) as a coupling agent. Compared with the glutaraldehyde-immobilized and the free enzyme, the THP-immobilized enzyme had the highest thermal stability with 78% activity retained after 12 days at 37 degrees C. The THP-immobilized enzyme also had higher reusability than that immobilized by glutaraldehyde, 75% activity was retained after 11 batches (or 11 days) at 37 degrees C for the THP immobilized enzyme system.

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An on-line device, ORP (oxidation-reduction potential)-stat, was used to control glucose-feeding for enhancing xylitol conversion from D-xylose during an oxygen-limited fermentation by Candida tropicalis. The fermentation was carried out in a 5 l jar fermenter. After glucose in the medium was depleted, a switching to a limited aeration and feeding glucose controlled by ORP-stat was performed.

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An on-line device, ORP (oxidation-reduction potential)-stat, was used to control glucose-feeding for enhancing xylitol conversion from D-xylose during an oxygen-limited fermentation by Candida tropicalis. The fermentation was carried out in a 5 l jar fermenter. After glucose in the medium was depleted, a switching to a limited aeration and feeding glucose controlled by ORP-stat was performed.

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A complex biocatalyst system with a bioreactor equipped with a microfiltration (MF) module was employed to produce high-content fructooligosaccharides (FOS) in a continuous process initiated by a batch process. The system used mycelia of Aspergillus japonicus CCRC 93007 or Aureobasidium pullulans ATCC 9348 with beta-fructofuranosidase activity and Gluconobacter oxydans ATCC 23771 with glucose dehydrogenase activity. Calcium carbonate slurry was used to control pH to 5.

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