Rice grain structural characteristics of sake rice cultivar Hakutsurunishiki for daiginjo-shu brewing.

Hakutsurunishiki is a sake rice cultivar bred using Yamadabo (seed parent) and Wataribune 2 (pollen parent), equivalent to a Yamadanishiki sibling. This study evaluated the structural characteristics of the Hakutsurunishiki rice grain that contribute to the brewing characteristics of daiginjo-shu, via a comparison with Yamadanishiki. Hakutsurunishiki brown rice was a little heavy and had a large white core. Observing a cross-section of white rice after soaking revealed that the rice grain structure of Hakutsurunishiki was different from that of Yamadanishiki. Hakutsurunishiki white rice showed fewer voids than Yamadanishiki, promoting a slower water absorption rate. Glucose distribution in rice koji obtained by mass spectrometry imaging showed that Hakutsurunishiki rice koji, like Yamadanishiki, is tsuki-haze type, suggesting that its grain structure is suitable for making rice koji for daiginjo-shu. With these observations, we were able to clarify the structural characteristics of Hakutsurunishiki rice grain.

Methanol bioeconomy: promotion of rice crop yield in paddy fields with microbial cells prepared from natural gas-derived C1 compound.

Methylotrophs, which can utilize methanol as a sole carbon source, are promising microorganisms to be exploited in a methanol-based bioeconomy, in which a variety of useful compounds are biotechnologically produced from natural gas-derived methanol. Pink-pigmented facultative methylotrophs (PPFMs) are common plant phyllospheric bacteria and are known to enhance seedling growth and total biomass of various plants. However, improvement of crop yield by inoculation of PPFMs at the field level has not been well investigated. We herein describe improvement of crop yield of several rice cultivars by foliar spraying of PPFMs. After selection of PPFM strains and rice cultivars by the in vitro seedling growth test, we further conducted paddy field experiments. The crop yield of the sake-brewing rice Oryza sativa cultivar Hakutsurunishiki was reproducibly improved in a commercial paddy field for over a 5-year period. A one-time foliar spray of PPFM cells (living or killed) or a cell wall polysaccharide fraction, after the heading date, acted in the phyllosphere and effectively improved crop yield. Our results show that the established process with PPFMs is feasible for improvement of food production in the methanol bioeconomy.

Analyzing the relationship between the inorganic element profile of sake dilution water and dimethyl trisulfide formation using multi-element profiling.

Dimethyl trisulfide (DMTS) is the main component of hineka, an off-flavor generated in sake during storage. Genshu, or undiluted sake, is usually diluted with water during warimizu, the process of adjusting the alcohol content of sake. In this study, we evaluated how the inorganic element composition of sake dilution water affects the DMTS-producing potential of the sake (DMTS-pp, determined as the DMTS concentration in sake stored at 70°C for 1 week after dilution) using inductively coupled plasma-mass spectrometry (ICP-MS). Partial least squares (PLS) regression analysis was conducted with the ICP-MS data as the explanatory variable and DMTS-pp as the response variable, and the selection of inorganic elements for the construction of the PLS model was performed using variable importance in projection scores. The findings confirmed that some of the compounds containing the inorganic elements extracted from the PLS regression analysis contribute to DMTS-pp.

Cycloartenyl trans-ferulate, a component of the bran byproduct of sake-brewing rice, inhibits mammalian DNA polymerase and suppresses inflammation.

During the screening of selective DNA polymerase (pol) inhibitors, we isolated cycloartenyl trans-ferulate (CAF), which is a major component of γ-oryzanol, which is a byproduct formed during the production of Japanese rice wine "sake". CAF selectively inhibited the activity of mammalian A, B, and X pol families, but Y family pols were not affected. CAF did not influence the activities of plant or prokaryotic pols, nor the activity of other DNA metabolic enzymes tested. Individual chemical components of CAF, including cycloartenol (CA) and ferulic acid (FA), did not inhibit pol enzyme activities. CAF suppressed TPA (12-O-tetradecanoylphorbol-13-acetate)-induced inflammation in the mouse ear, but CA and FA did not. The ability to inhibit mammalian pol enzymes in vitro was positively correlated with their propensity to suppress inflammation in vivo. These results suggest that this byproduct formed during the sake-brewing process is useful as an anti-inflammatory agent.

Linoleoyl ethanolamide reduces lipopolysaccharide-induced inflammation in macrophages and ameliorates 2,4-dinitrofluorobenzene-induced contact dermatitis in mice.

In our previous study, it was found that linoleoyl ethanolamide (LE) is present in sake lees, which are produced as a byproduct during the making of Japanese sake. LE is a fatty acid ethanolamide, which have been demonstrated to exert a variety of biological functions, and in this study, the anti-inflammatory effects of LE were examined using in vitro cell culture and in vivo animal experiments. In mouse RAW264.7 macrophages, LE suppressed the lipopolysaccharide (LPS)-induced expression of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and IL-6. In addition, LE inhibited LPS-induced increases in the levels of cyclooxygenase enzyme-2 and prostaglandin E(2), which are indicators of inflammation. The inhibitory effect of LE on the release of TNF-α was stronger than that of dipotassium glycyrrhizinate, which is widely used in external human skin care treatments. LE also suppressed the LPS-induced activation of Toll-like receptor 4 signaling and nuclear translocation of nuclear factor-κB (NF-κB) p65. In a contact dermatitis animal model, applying LE to affected ear skin ameliorated 2,4-dinitrofluorobenzene-induced contact dermatitis and pro-inflammatory cytokine expression at inflamed sites. These results indicate that LE exerts anti-inflammatory effects by inhibiting NF-κB signaling, and LE is proposed to be a useful therapeutic agent against contact dermatitis.