Mitsuoki Kaneoke

Sake Lees Fermented with Lactic Acid Bacteria Prevents Allergic Rhinitis-Like Symptoms and IgE-Mediated Basophil Degranulation

We tested the effect of oral administration of fermented sake lees with lactic acid bacteria (FESLAB) on a murine model of allergic rhinitis upon immunization and nasal sensitization with ovalbumin (OVA). We used Lactobacillus paracasei NPSRIk-4 (isolated from sake lees), and L. brevis NPSRIv-8 (from fermented milk) as starter strains to produce the FESLAB. Oral FESLAB administration resulted in the development of significantly fewer sneezing symptoms than those seen in sham control animals given sterile water. We also found that FESLAB suppressed the allergen-induced degranulation of RBL2H3 rat basophilic leukemia cells.

Analysis of Free Fatty Acids in Sake by an Enzymatic Method and Its Application for Estimating Ethyl Caproate and Selecting Yeast with High Productivity of the Ester

We show that the concentration of total free fatty acids (FFAs) in sake produced by yeast with high productivity of ethyl caproate could be approximated by the concentration of 2 FFAs, caproic and caprylic acids. Measurement of the total FFAs concentration by an enzymatic method proved useful for both estimating the ethyl caproate concentration in sake and also for yeast breeding.

Polishing Properties of Sake Rice Koshitanrei for High-Quality Sake Brewing

The Japanese high-quality sake Daiginjo-shu is made from highly polished rice (polishing ratio, less than 50%). Here we showed that the sake rice Koshitanrei (KOS) has an excellent polishing property. Rice grains of KOS had the same lined white-core region as the sake rice Yamadanishiki (YAM). The grain rigidity/hardness of KOS was higher than that of the sake rice Gohyakumangoku (GOM). The loss ratio of KOS after high polishing by an industrial polishing machine was lower than that of GOM. Further, a clear taste of sake produced from KOS was confirmed by sensory evaluation.

Growth-inhibition of hiochi bacteria in namazake (raw sake) by bacteriocins from lactic acid bacteria

The bacteriocins produced by Lactococcus lactis subsp. lactis C101910 (C101910) and NBRC 12007 (NBRC 12007) were used to prevent the growth of sake spoiling hiochi bacteria (Lactobacillus hilgardii, Lactobacillus fructivorans, and Lactobacillus paracasei) in namazake, which is raw (unpasteurized) sake. The bacteriocin concentrations required for decreasing the viable cell concentrations of L. hilgardii and L. fructivorans below the detection limit (1.0 x 10(2) cells/ml) in 24 h from the initial concentration of 4.0-9.5 x 10(5) cells/ml in the namazake at pH 4.5 and at 4 degrees C, were 18-35 U/ml and 5.6 U/ml for the bacteriocin from C101910 and NBRC 12007, respectively. To decrease the viable cell concentration of L. paracasei from the initial concentration of 7.5 x 10(5) cells/ml to below the detection limit (1.0 x 10(2) cells/ml) in 24 h, 350 U/ml bacteriocin from C101910 and 140 U/ml bacteriocin from NBRC 12007 were required. In experiments using McIlvaine buffer (pH 4.5) with 15% ethanol instead of namazake as the medium, the viable cell concentrations of L. hilgardii and L. paracasei decreased to less than 1.0 x 10(2) cells/ml, whereas those of L. fructivorans decreased to less than 1.0 x 10(3) cells/ml, when bacteriocins were added at the concentrations that had proven effective in namazake. The membrane depolarization assay using a fluorescent probe showed that the presence of ethanol stimulated the collapse of the membrane potential induced by bacteriocins. The ethanol induced collapse of the membrane potential suggests that the application of bacteriocins at the storage stage of namazake is more beneficial than when used in other stages of the sake brewing process.

Isolation of a Non-Urea-Producing Sake Yeast Strain Carrying a Discriminable Molecular Marker

In the fermentation industry, the traceability of microorganisms during the process is important to ensure safety and efficacy. Ethyl carbamate, a group-2A carcinogen, is produced from ethanol and urea during the storage of food/alcoholic beverages. We isolated non-urea-producing sake yeast car1 mutants carrying a discriminable molecular marker, and demonstrated, by the use of PCR assays, that these mutants are useful for traceability analysis and identification during the sake brewing process.

Simple differentiation of sake (Japanese alcoholic beverage) based on trace inorganic components using colorimetric methods

Several colorimetric methods were combined and used for the discrimination of commercial sake samples, based on their constituent inorganic components. The method was very rapid, simple, and did not require expensive equipment. Further, we showed that this method has potential application in immediate differentiation of sake by the visual inspection.

Diguanidinobutanase of Pseudomonas putida and enzymatic preparation of agmatine from 1,4-diguanidinobutane

Diguanidinobutanase (EC 3.5.3.20), which catalyses the hydrolysis of 1,4-diguanidinobutane (DGB) to agmatine (1-amino-4-guanidinobutane) and urea, was purified to homogeneity from Pseudomonas putida ATCC 12633. The enzyme had a molecular mass of 170 kDa and was suggested to be a tetramer of subunits that had a molecular mass of 38 kDa. The enzyme contained two Mn2+ ions per subunit. DGB was the most effective substrate and its Km was 0.65 mM. The turnover number for the subunit at saturation with DGB was 1330 molecules s−1. The higher homologues of DGB with five to seven methylene groups were also hydrolysed effectively. Agmatine was hydrolysed at a rate of 0.6% of that observed with DGB. The agmatine homologues with five to seven methylene groups were hydrolysed, although the rates were low. The enzyme was sensitive to p-chloromercuribenzoate. Agmatine sulphate was enzymatically prepared from DGB. The purified product, free from detectable putrescine and DGB, was obtained with a yield of 93% (mol/mol).

Differentiation of industrial sake yeast strains by a loop-mediated isothermal amplification method that targets the PHO3 gene.

We developed a loop-mediated isothermal amplification method that targets the PHO3 gene for discriminating sake yeast strains. Our data indicate that this assay is simple, rapid, and useful to use for differentiation of specific yeasts in sake mash.