Comparison of the odor-active compounds in unhopped beer and beers hopped with different hop varieties

Odorants comprising the hop aromas of beers were examined. Strongly hopped beers with Saazer, Hersbrucker, and Cascade hops were compared with unhopped beer by gas chromatography-olfactometry (CharmAnalysis) and sensory evaluation. Twenty-seven odorants were revealed as hop-derived, which derived either directly from hops or via metabolization, and 19 components were identified. Of the components, linalool, geraniol, ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, and ethyl 2-methylpropanoate were determined as odor-active components from their Charm values and aroma values. The muscat-like aroma of Cascade beer and the spicy aroma of Hersbrucker beer were predominant in sensory evaluation, and the contributors to these characteristics were investigated.     

Delineation of Japanese soil temperature regime map

The soil temperature regime map provides for utilitarian classification that can be superimposed on soil classification to permit more precise interpretations and assessments of land use. The objects of this study are (1) to clarify the relationship between soil temperature and meteo-geographical factors, and then (2) to delineate detailed soil temperature regime map (1?km grid) as Japanese land resources inventory. There was a parallel relationship between mean annual soil temperature (MAST) and mean annual air temperature (MAAT), but this relationship was affected to some extent by the mean annual wind speed and mean annual global irradiation in this study. Furthermore, the difference between MAST and MAAT [Diff(MAST–MAAT)] showed the highest correlation with elevation. The map of RK_Diff(MAST–MAAT) was computed using this meteo-geographical relationship with the regression-kriging approach, and then the map of MAST and the soil temperature regime map were delineated using the map of MAAT and the RK_Diff(MAST–MAAT). The root mean square error of this delineation procedure was 0.47°C. It was clear that the majority of the Japanese soils had “mesic” soil temperature regime, and Japanese agricultural land was mainly distributed at “mesic” area and followed by “thermic”, “frigid”, and “hyperthermic” area. For promoting this land resource inventory, the soil temperature regime map will be uploaded on “Soil Information Web Viewer (http://agrimesh.dc.affrc.go.jp/soil_db/)”, which is provided by the National Institute for Agro-Environmental Sciences.     

Change in river water chemistry as affected by the confluence of forest drainage water in dairy farming area on Hokkaido Island, Northern Japan

We evaluated i) the difference in river water chemistry between a watershed mainly consisting of pasture and a watershed mainly consisting of forest, and ii) how the chemistry of river draining the pasture is influenced by that of the river draining the forest. We selected one river (designated as the T-river) draining the pasture (3,587 ha), and two rivers draining a forest (738 and 879 ha) in eastern Hokkaido, northern Japan. During higher river flow due to precipitation and thawing, the concentrations of NO ₃ ⁻ , SO ₄ ²⁻ , K⁺, Fe, and Al increased, suggesting the relative importance of the shallow soil layer as their source. On the other hand, Na⁺, Mg²⁺, Ca²⁺, and Si decreased, suggesting the relative importance of the source in a deep soil layer. The concentrations of NO ₃ ⁻ , Cl⁻, SO ₄ ²⁻ , K⁺, Na⁺, Mg²⁺, Ca²⁺, and Fe were higher in the T-river than in the forest drainage waters, suggesting the contribution of the excretion components from the milk cows. The Si concentration exhibited the opposite pattern. The concentrations of NO ₃ ⁻ , Cl⁻, SO ₄ ²⁻ , K⁺, Na⁺, Mg²⁺, Ca²⁺ (p<0.001), and Fe (p<0.05) in the T-river decreased after the confluence of the forest drainage waters, while Si concentration increased (p<0.001). The reason for the change in river chemistry was the confluence of the forest drainage waters. These findings suggested the environmental role of the forest in the dilution of the polluted river. Prof. S. Ohata, and Prof. H. Takeda, Graduate School of Agriculture, Kyoto University, facilitated this study. Prof. T. Sakai, Graduate School of Informatics, Kyoto University, offered this study some convenience. Dr. M. Sakimoto, and Dr. M. Katsuyama, Graduate School of Agriculture, Kyoto University, offered useful advise.     

Highly regioselective amination of unactivated alkanes by hypervalent sulfonylimino-λ³-bromane

Amination of alkanes has generally required metal catalysts and/or high temperatures. Here we report that simple exposure of a broad range of alkanes to N-triflylimino-λ(3)-bromane 1 at ambient temperature results in C-H insertion of the nitrogen functionality to afford triflyl-substituted amines in moderate to high yields. Marked selectivity for tertiary over secondary C-H bonds was observed; primary (methyl) C-H bonds were inert. Addition of hexafluoroisopropanol to inhibit decomposition of 1 dramatically improved the C-H amination efficiencies. Second-order kinetics, activation parameters (negative activation entropy), deuterium isotope effects, and theoretical calculations suggest a concerted asynchronous bimolecular transition state for the metal-free C-H amination event.     

Structural conservation of the <Emphasis Type="Italic">hrp</Emphasis> gene cluster in <Emphasis Type="Italic">Xanthomons oryzae</Emphasis> pv. <Emphasis Type="Italic">oryzae</Emphasis>

The clustered hrp genes encoding the type III secretion system in the Japanese strains MAFF301237 and MAFF311018 of Xanthomonas oryzae pv. oryzae were sequenced and compared. The strains differ in their pathogenicity, location, and year of isolation. A 30-kbp sequence comprising 29 open reading frames (ORFs) was identical in its structural arrangement in both strains but differed from X. campestris pv. campestris, X. axonopodis pv. citri, and X. axonopodis pv. glycines in certain genes located between the hpaB-hrpF interspace region. The DNA sequence and the putative amino acid sequence in each ORF was also identical in both X. oryzae pv. oryzae strains as were the PIP boxes and the relative sequences. These facts clearly showed that the structure of the hrp gene cluster in X. oryzae pv. oryzae is unique.     

Nebulin and N-WASP cooperate to cause IGF-1-induced sarcomeric actin filament formation

Insulin-like growth factor 1 (IGF-1) induces skeletal muscle maturation and enlargement (hypertrophy). These responses require protein synthesis and myofibril formation (myofibrillogenesis). However, the signaling mechanisms of myofibrillogenesis remain obscure. We found that IGF-1-induced phosphatidylinositol 3-kinase-Akt signaling formed a complex of nebulin and N-WASP at the Z bands of myofibrils by interfering with glycogen synthase kinase-3β in mice. Although N-WASP is known to be an activator of the Arp2/3 complex to form branched actin filaments, the nebulin-N-WASP complex caused actin nucleation for unbranched actin filament formation from the Z bands without the Arp2/3 complex. Furthermore, N-WASP was required for IGF-1-induced muscle hypertrophy. These findings present the mechanisms of IGF-1-induced actin filament formation in myofibrillogenesis required for muscle maturation and hypertrophy and a mechanism of actin nucleation.     

Purification and characterization of an angiotensin I‐converting enzyme inhibitory peptide derived from porcine troponin C

To search for a novel angiotensin I‐converting enzyme (ACE) inhibitory peptide, porcine skeletal troponin was hydrolyzed with pepsin. This hydrolysate showed ACE inhibitory activity, and was applied to various kinds of chromatography to separate an active peptide. Analysis using a protein sequencer identified this peptide as RMLGQTPTK (9mer). This sequence was estimated to occur at the 44–52 position of troponin C, and its 50% inhibitory protein concentration (IC₅₀) was 34 µM. RMLGQTP (7mer), a partial peptide of 9mer, showed activity with an IC₅₀ of 503 µM. RP‐HPLC analysis of a reaction mixture of 9mer and ACE showed that 9mer was slowly hydrolyzed by ACE. On the other hand, 7mer was rapidly hydrolyzed by ACE. Activity of 9mer was reduced as its hydrolysis by ACE proceeded. To estimate the resistance of 9mer to digestive proteases after oral administration, it was reacted with pepsin, α‐chymotrypsin, or trypsin. In each of these reaction mixtures, a significant amount of 9mer remained as a substrate after digestion. Remaining ACE inhibitory activity was close to that of 9mer. These results suggest that 9mer might not be digested after oral administration, because of its relatively high resistance to digestive proteases. Therefore, 9mer might be expected to work well in vivo as an ACE inhibitor.     

Effect of injection on bed shear stress and turbulence characteristics in a closed conduit flow

Bed shear stress and turbulence quantities are important parameters to understand sediment erosion, transport, and hydraulic processes in most hydraulic studies. An experimental investigation was conducted to understand the effect of injection on the bed shear stress and turbulence characteristics of flows during low sediment transport rate in a closed conduit, which is similar in construction to the erosion function apparatus. In particular, the effect of injection on the bed shear stress, mean velocity profiles, turbulence intensities, Reynolds shear stress, and higher-order moments of the closed conduit flows in the seepage zone as well as at the upstream edge of the seepage zone was examined. The instantaneous velocities were measured using two-dimensional particle image velocimetry (PIV) to evaluate the turbulence structure in both the seepage zone and at the upstream edge of the seepage zone. The bed shear stress estimated by the Reynolds shear stress approach was found to be more appropriate than that estimated by the usual logarithmic law approach. However, a spatial fluctuation in the bed shear stress was noticed as the injection intensity was increased. Injection was found to decrease the velocity near the bed and to increase the velocity near the center of the conduit in comparison to the no-seepage condition in both zones. The injection resulted in more of a decrease in bed stability in the seepage zone in comparison to the upstream edge of the seepage zone as the injection intensities were increased. The introduction of injection increased the magnitudes of the various turbulence parameters in comparison to the no-seepage condition in the seepage zone. The effect of injection was not only visible in the near-bed region, but in both zones as the water depth (measured from top of the sediment surface) increased.

     

Relationship between pH and Temperature in the Ruminal Fluid of Cows, Based on a Radio-Transmission pH-Measurement System

To assess the relationship between pH and temperature in the ruminal bottom fluid, circadian changes were monitored using cows fed a control diet (C diet) or a rumen acidosis-inducing diet (RAI diet) by using a wireless radio-transmission pH- measurement system. These two parameters were measured simultaneously at 10-min intervals on day 14 after commencement of feeding. Compared to the mean ruminal pH for 60 min immediately after the morning feeding (0 hr), significantly lower pH was noted 3-13 hr later (P<0.05) and 4-19 hr later (P<0.01) in cows fed the C and RAI diets, respectively, although the reduction in the latter was much higher than that in the former. In contrast, significantly higher ruminal temperature was found at 8 and 12-14 hr later (P<0.05) and 6, 8, and 10-19 hr later (P<0.01) in cows fed the C and RAI diets, respectively. A significant negative correlation was observed between the lowest ruminal pH and its corresponding ruminal temperature in cows fed the C and RAI diets (r=-0.722 and -0.650, P<0.01, respectively), suggesting active fermentation and volatile fatty acid production in the rumen. However, ruminal pH profiles may not be predictable by measuring only ruminal temperature because decreases in ruminal pH were preceded by increases in ruminal temperature, and circadian changes in pH and temperature were associated with ruminal fermentation.     

Properties of Microbial Biomass in Acid Soils and Their Turnover

The soil microbial biomass is important such as pool of plant nutrients and is also driving force of the cycling of C, N, P and S in soil. However, the microbial biomass in acid soil has not been fully investigated due to the limitation of methods, i.e. chloroform-fumigation incubation or substrate-induced respiration because of decreased basal mineralization in chloroform-fumigated soil under acid conditions. This paper reviews improvement and application of these methods and vertical distribution of microbial biomass in two kinds of acid soils; namely, Andisols as dominant upland soils in Japan and tropical peat soils as potentially important lowland soils for agriculture, and also discuss on C and N turnover of microbial biomass in Andisols. Microbial succession in acid soil has also not been investigated so much, but, some studies in another important acid soil, i.e. acid sulfate soil, were also reviewed briefly.