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Mushrooms of the Omphalotus genus are known to be rich in secondary metabolites. In the quest for new bioactive compounds, we analyzed the compounds isolated from the mycelium of the poisonous mushroom Omphalotus japonicus. As a result, a new polyisoprenepolyol, which was named omphaloprenol A, was identified, along with known substances such as hypsiziprenol A10 and A11, illudin S, and ergosterol. The chemical structure of omphaloprenol A was elucidated by nuclear magnetic resonance and infrared spectroscopies and mass spectrometry, and its bioactivity was investigated. Omphaloprenol A showed growth promoting activity against the root of lettuce seeds and cytotoxicity against HL60 cells. To the best of our knowledge, this is the first report on the isolation of a polyisoprenepolyol compound from Omphalotaceae mushrooms.

Six new sesquiterpenes, tsukiyols A-C, neoilludin C, and 4-O-methylneoilludins A and B, were isolated from the fruiting body of Omphalotus japonicus (Kawam.) Kirchm. & O. K. Mill. Additionally, six known compounds, illudin S, neoilludins A-B, 5-hydroxydichomitol, ergosterolperoxide, and 3β,5α,9α-trihydroxyergosta-7,22-diene-6-one, were also obtained. Their chemical structures were determined with MS, IR, and NMR spectra and the absolute configurations of neoilludins A-C, 4-O-methylneoilludins A, and B were determined with electronic circular dichroism (ECD). Illudin S and 3β,5α,9α-trihydroxyergosta-7,22-diene-6-one showed cytotoxicity against human acute promyelocytic leukemia HL60 cells. Illudin S, 4-O-methylneoilludin A, B, and tsukiyol C showed growth-restoring activity against mutant yeast via Ca2+-signal transduction.

To clarify the thermal hazards of acrylic acid runaway polymerization, the amount of energy release and the products in each event of the polymerization sequence were investigated. The thermal hazard was analyzed using accelerating rate calorimetry (ARC), Karl-Fisher titration, and thermogravimetry-differential thermal analysis-mass spectrometry (TG-DTA-MS). The present study revealed that acrylic acid generates water, which increases the impact of tank destruction when the tank filling level is more than 15%. In addition, the Michael addition reaction of acrylic acid induces the monomer to polymerize due to its exotherm and produce Michael adducts, which generate larger amounts of gases and water than does the monomer. Therefore, the accumulation of Michael adducts increases the frequency of crack initiation in the tank, as well as the potential for tank destruction, due to the presence of monomer and water in the tank at a lower filling level than in the case of monomer alone. The present study determined that the accumulation of Michael adducts is the worst case scenario for accidents caused by acrylic acid.

Six new sesquiterpenes, tsukiyols A-C, neoilludin C, and 4-O-methylneoilludins A and B, were isolated from the fruiting body of Omphalotus japonicus (Kawam.) Kirchm.O. K. Mill. Additionally, six known compounds, illudin S, neoilludins A-B, 5-hydroxydichomitol, ergosterolperoxide, and 3β,5α,9α-trihydroxyergosta-7,22-diene-6-one, were also obtained. Their chemical structures were determined with MS, IR, and NMR spectra and the absolute configurations of neoilludins A-C, 4-O-methylneoilludins A, and B were determined with electronic circular dichroism (ECD). Illudin S and 3β,5α,9α-trihydroxyergosta-7,22-diene-6-one showed cytotoxicity against human acute promyelocytic leukemia HL60 cells. Illudin S, 4-O-methylneoilludin A, B, and tsukiyol C showed growth-restoring activity against mutant yeast via Ca

The purpose of this study is to obtain a better understanding of Michael addition reaction (MAR) which may induce runaway polymerization of acrylic acid. The heat of MAR was measured using a C80 Calvet-type heat flux calorimeter, and products of MAR were revealed by gel permeation chromatography. The reaction rate constant of MAR was obtained from kinetic analysis. In high-sensitivity calorimetry, a low rate of heat release due to MAR was detected. The heat of MAR was 109 J g−1 and conversion of acrylic acid to Michael adducts was 82 mass%. The products of MAR were acrylic acid dimers, trimers and tetramers. The reaction order was 2.5th, and the overall reaction rate constant was k = 3.52 × 103 × exp (−1.18 × 105/T [K]) L1.5 mol−1.5 s−1. The activation energy of MAR was 98.0 kJ mol−1, which was similar in value to that of dimerization in previous studies. This indicated that dimer formation is the dominant reaction in MAR.

Dimethyl sulfoxide (DMSO) has been extensively used as a solvent because of its high-performance characteristics. However, there have been accidents when DMSO has been used in some chemical processes (Lam et al. in J Therm Anal Calorim 85:25–30, 2006; http://riscad.db.aist.go.jp/PHP_EN/index.php ). Although the decomposition mechanism of DMSO under acidic conditions is known (Santosusso et al. in Tetrahedron Lett 48:4255–4258, 1974), the number of studies about thermal behavior of DMSO under acidic condition is not large. The purpose of this investigation is to understand the decomposition thermal behavior of DMSO under acidic conditions. Thermal analysis using an accelerating rate calorimeter (ARC) was carried out with acids chosen for their acid dissociation degree constant (pKa), which is a typical parameter of acid strength. ARC data show that the self-heat rate increased and the exothermic onset temperature decreased with decreasing pKa. Additionally, the exothermic onset temperature and pKa had good linear correlation. To verify the initial exothermic reaction, differential scanning calorimetry (DSC) analysis was carried out. DSC results showed that the exothermic onset temperature was due to decomposition of DMSO. The activation energy of the decomposition reaction was calculated from the ARC results (self-heat rate). Our data indicate that the activation energy of the decomposition reaction decreased with decreasing pKa. Therefore, thermal hazards of DMSO increase with the decrease in pKa, with good linear correlation.

The influence of the atmospheric conditions such as the oxygen concentration and its pressure on the spontaneous ignition behaviour of activated carbon was investigated with high pressure DSC (HP-DSC), TG-DTA and SIT (spontaneous ignition test). The onset temperature with HP-DSC lowered with the increase of the oxygen concentration and the onset temperature could be predicted with the oxygen concentration. From the adiabatic self-heating profiles observed by SIT the onset temperature lowered with the increase of the oxygen concentration and the activation energy of induction period of exothermic reaction was determined as 28~39 kJ mol-1.

This is the first comprehensive study on the kinetic modeling of adiabatic decomposition of di-tert-butyl peroxide (DTBP) and its solvent mixtures. The adiabatic thermal decomposition of DTBP and its solvent mixtures was examined using an accelerating rate calorimeter under varying thermal inertia. The decomposition products were characterized using gas chromatography−total inorganic carbon analysis and gas chromatography−mass spectroscopy to elucidate the mechanistic pathways for decomposition under adiabatic conditions. Reaction models (overall stoichiometric equations) for the decomposition of neat DTBP and its mixture in various solvents have been proposed for the first time. A comprehensive kinetic analysis based on simultaneous treatment of mass and energy balances has been done using a software called BatchCAD. The activation energies for the decomposition of DTBP and its mixtures in various solvents were quite consistent. This comprehensive study has answered to many ambiguities and questions on t...

The Vilsmeier reaction is one of the important reactions in the organic photoconductor industry, and quantitative information of thermal hazards of the reaction is needed for process control and safety. In this report, the thermal hazards of Vilsmeier reaction are investigated, and heats of reaction are measured using reaction calorimeters. It is found that the thermal decomposition of the Vilsmeier complex is the maximum hazard in this reaction and that the selection of reaction procedure and solvent might be a key for the suitable reaction.

A new 1.3 l engine developed for the 2002 model Honda “Fit” achieves high fuel economy (23 km/l in the Japanese 10.15 mode) and more than 50% emissions reduction from the 2000 standards in Japan. This engine has dual spark plugs that are located in a diagonal position in order to conduct the flame closely, and which control the ignition sequentially to burn rapidly. In addition, new technology of shot peening with MoS 2 reduced mechanical friction and a six-hole injector and oblique structuring converter reduced its emissions.

To evaluate the thermal hazard of self-reactive substances in chemical processes, the time to maximum rate (TMR) of autocatalytic decomposition reaction of cumenehydroperoxide (CHP) was determined by calculations based on the results of isothermal measurement using DSC and heat conduction calorimeter. In addition, the factors affecting the calculated results were investigated. It was found that the TMR is affected by the catalytic action of the sample vessel metal. When this effect is taken into account in analyzing the experimental result, the predicted TMR shows a good agreement with the value determined using the adiabatic reaction calorimeter. The present study clarified that the proposed technique would enable the appropriate evaluation of thermal hazard of an autocatalytic reaction.

Background There is a need for a pancreatic lipase (LIP) reference assay to provide an accurate base to which routine methods can be traceable. Methods This study developed a novel LIP assay method in which 1,2-dioleoylglycerol (DODG) is the substrate and LIP activity is measured in a coupled enzymatic reaction from the increase in absorbance at 340 nm with production of NADPH. Results With this method, LIP activity was linear up to 440 U/L (8-times expected upper limit of physiological concentration). When assayed manually, the between-laboratory variation for six samples surveyed at five laboratories was 3.80-26.4% (CV) for samples containing about 20-290 U/L LIP activity; when assayed using an automated analyzer, the range was 1.86-4.86% (four laboratories). Interference by >5 mmol/L glycerol and low specificity with post-heparin samples were noted, but in practice these are avoidable. Precision analyzed by automated assay of 49 samples twice in random order produced a covariance of 2.27 U/L, which is comparable to routine methods, and good correlations were obtained with five routine methods. Conclusions Although further studies are required, the DODG method may be likely applicable as one candidate reference method.

The medical criteria for initiating insulin therapy, based on clinical profiles of type 2 diabetic patients, have not yet been clearly established. We explored various parameters with 48 type 2 diabetic patients who were taking oral hypoglycemic medication. Among parameters, body mass index (BMI), the fasting plasma glucose level (FPG), and plasma chloride concentration were identified by forward-stepwise discriminant analysis as parameters that can discriminate between patients who were and those who were not undergoing insulin therapy. In combination, these parameters correctly diagnosed 86.4% of the patients who were undergoing insulin therapy, and 84.6% of those who were not undergoing insulin therapy. Further, we observed significant correlations between plasma chloride concentrations and either plasma sodium or organic acid concentrations, suggesting that impaired insulin action may reduce plasma chloride concentrations through changes in plasma sodium and organic acid metabolism. Our results suggest that plasma chloride concentration is a possible new indicator of insulin insufficiency.

Publisher Summary This chapter examines the thermal hazard of Vilsmeier reaction and measures the heats of reaction using reaction calorimeters. It was found that the thermal decomposition of the Vilsmeier complex and selection of the solvent might be a key for the suitable reaction. Formylation of aromatic compounds using the Vilsmeier complex is a popular reaction in the chemical industry, especially in organic photoconductor manufactures. The Vilsmeier complex is usually prepared by the reaction of phosphorus oxychloride (POCI3) and N, N-dimethyleformamide (DMF) or N-methylformamide (MFA). The theoretical calculation of the heat of decomposition of the complex is generally difficult because of its structure, therefore, the experimental measurement of thermal behavior using reaction calorimetry technique is useful for the hazard evaluation. It is presumed that the Vilsmeier complex does not exist when reagents are mixed at lower temperature and the complex is produced with the temperature rise. It is considered that POCI3 are solvated with coordinating to DMF. Therefore, the reaction heat of the Vilsmeier complex depends on the temperature of the system. Vilsmeier reaction is one of important reactions in organic photoconductor industry, and quantitative information of thermal hazard of the reaction is needed for the process control and safety.