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We previously found that vitamin K(3) (menadione, 2-methyl-1,4-naphthoquinone) inhibits the activity of human mitochondrial DNA polymerase γ (pol γ). In this study, we focused on juglone (5-hydroxy-1,4-naphthoquinone), which is a 1,4-naphthoquinone derivative, and chemically synthesized novel juglones conjugated with C2:0 to C22:6 fatty acid (5-O-acyl(More)
We previously found that vitamin K3 (menadione, 2-methyl-1,4-naphthoquinone) inhibits the activity of human mitochondrial DNA polymerase γ (pol γ). In this study, we focused on plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone), and chemically synthesized novel plumbagins conjugated with C2:0 to C22:6 fatty acids (5-O-acyl plumbagins). These chemically(More)
A three-dimensional cardiomyocyte gel was reconstructed using an extracellular matrix gel formed from Matrigel and collagen I. The autonomous beating of the cardiomyocyte gel was synchronized with contraction of cardiomyocytes in the gel. The gel beating frequency was increased by increasing the concentration of adrenaline in the cardiomyocyte culturing(More)
A transglycosylation reaction with moranoline (1-deoxynojirimycin) was done with soluble starch as the glucosyl donor and Bacillus macerans amylase as a cyclodextrin glycosyltransferase [EC 2.4.1.19]. The resultant transglycosylation products with moranoline, obtained by treating the reaction mixture with a strong cation exchange resin, were hydrolyzed by(More)
A biomimetic synthesis of zeylanone and zeylanone epoxide, which are natural dimeric naphthoquinones, has been accomplished starting from plumbagin, a natural monomeric naphthoquinone. The key features of our synthesis are cascade intermolecular and intramolecular Michael reactions, followed by epoxidation of the resultant hydroquinone with molecular oxygen.
A transgalactosylation reaction from lactose to moranoline (1-deoxynojirimycin) was accomplished by using beta-galactosidase [EC 3.2.1.23] from Bacillus circulans. The enzyme formed 3-O-beta-D-galactopyranosyl-moranoline and 4-O-beta-D-galactopyranosyl-moranoline as major products, together with 2-O-beta-D-galactopyranosyl-moranoline and(More)
In repeated glycosylmoranolines synthetic reaction at 55 degrees C, cyclodextrin glycosyltransferase (CGT-ase, EC 2.4.1.19) from Bacillus stearothermophilus retained its activity for more than 600 days. A main stabilizing compound was found to be 4-O-alpha-D-glucopyranosylmoranoline. The thermostabilizing activities of moranoline,(More)
A novel and efficient procedure named "reducing end modification method" was developed for manufacturing high purity maltooligosaccharides. By the method, high purity maltose and maltotetraose were prepared from starch. Starch was liquefied, debranched, and oxidized with sodium hypochlorite at the reducing end. The reaction mixture was treated with(More)
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