Publications by authors named "Koji Kakugawa"

Bread is rich in dietary fibre and many phytochemical compounds, which may influence chemoprevention of colon cancer. In the present study, we evaluated the effect of three kinds of bread on DMH-induced colorectal tumours in F344 rats. F344 rats were divided into four groups (Steinmetz Three-Grain bread, Steinmetz Country bread, White bread, and MF).

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Mannosylerythritol (ME) is the hydrophilic backbone of mannosylerythritol lipids as the most promising biosurfactants produced by different Pseudozyma yeasts, and has been receiving attention as a new sugar alcohol. Different Pseudozyma yeasts were examined for the sugar alcohol production using glucose as the sole carbon source. P.

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Article Synopsis
  • - Bacillus subtilis has 10 rRNA operons, but researchers engineered a strain (RIK543) to have only one, the rrnO operon.
  • - This engineered strain shows a hypersensitivity to RNA polymerase inhibitors like rifamycin SV and rifampin, with increased sensitivity by 80-fold and 20-fold, respectively.
  • - In tests, RIK543 was used to identify new antibacterials from actinomycete isolates, successfully detecting compounds in 1.9% of samples (18 out of 945), suggesting it's a useful tool for discovering novel RNA polymerase inhibitors.
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Mannosylerythritol lipids (MELs) are one of the most promising biosurfactants known because of their multifunctionality and biocompatibility. A previously isolated yeast strain, Pseudozyma sp. KM-59, mainly produced a hydrophilic MEL, namely MEL-C (4-O-[4'-O-acetyl-2',3'-di-O-alka(e)noyl-beta-D: -mannopyranosyl]-D: -erythritol).

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Mannosylerythritol lipids (MEL), which are abundantly secreted by yeasts, are one of the most promising biosurfactants known. To obtain various types of MEL and to attain a broad range of applications for them, screening of novel producers was undertaken. Thirteen strains of yeasts were successfully isolated as potential MEL producers; they showed high production yields of MEL of around 20 g l(-1) from 40 g l(-1) of soybean oil.

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A cDNA clone of the lipase secreted by Kurtzmanomyces sp. I-11 was isolated from a cDNA library of this yeast by PCR screening using oligonucleotide primers designed on the basis of the partial amino acid sequence of the lipase. The cloned cDNA (lip1) encoded a hydrophobic protein of 484 amino acids, where the first 20 amino acids and the following 6 amino acid sequences were predicted to be the signal sequence for secretion and a pro-sequence, respectively.

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An extracellular lipase produced by the glycolipid-producing yeast Kurtzmanomyces sp. I-11 was purified by ammonium sulfate precipitation and column chromatographies on DEAE-Sephadex A-25, SP-Sephadex C-50, and Sephadex G-100. Based on the analysis of the purified lipase on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the purified lipase was judged to be homogeneous and its molecular mass was estimated to be approximately 49 kDa.

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Yeast strains were screened for producers of glycolipid-type biosurfactants from soybean oil as a sole carbon source. The structure of the glycolipid (MEL-I-11) produced by strain I-11 was analyzed. The hydrophilic sugar moiety was mannosylerythritol and the fatty acid components were C8:0 (36.

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