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To clarify the suppression of postprandial blood glucose rise via a a-glucosidase (AGH) inhibitory action by natural compounds, propolis was examined in this study. A single oral administration of propolis extract (50% methanol fraction on XAD-2 column chromatography) in Sprague-Dawley rats demonstrated a potent antihyperglycemic effect with the significant AUC 0-120 min reduction of 38% at a dose of 20 mg/kg compared to that of controls. Among the active compounds isolated from the fraction, 3,4,5-tri-caffeoylquinic acid was found to be a prominent candidate that exerts the effect and shows a strong maltase-specific inhibition with an IC 50 value of 24 m mM. In addition, the noncompetitive inhibition power apparently increased with the number of caffeoyl groups bound to quinic acid.

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The dry rot fungus Serpula lacrymans (Basidiomycota) is the most damaging destroyer of wood construction materials in temperate regions. While being a widespread aggressive indoor biodeterioration agent, it is only found in a few natural environments. The geographical source of spread and colonization by this fungus in human environments is thus somewhat of an enigma. Employing genetic markers (amplified fragment length polymorphisms, DNA sequences and microsatellites) on a worldwide sample of specimens, we show that the dry rot fungus is divided into two main lineages; one nonaggressive residing naturally in North America and Asia (var. shastensis), and another aggressive lineage including specimens from all continents, both from natural environments and buildings (var. lacrymans). Our genetic analyses indicate that the two lineages represent well-differentiated cryptic species. Genetic analyses pinpoint mainland Asia as the origin of the aggressive form var. lacrymans. A few aggressive genotypes have migrated worldwide from Asia to Europe, North and South America and Oceania followed by local population expansions. The very low genetic variation in the founder populations indicate that they have established through recent founder events, for example by infected wood materials transported over land or sea. A separate colonization has happened from mainland Asia to Japan. Our data also indicate that independent immigration events have happened to Oceania from different continents followed by admixture.

Summary Four softwood and three hardwood species were liquefied using polyethylene glycol (PEG) or glycerol-containing PEG solvent systems as liquefaction reagents under defined reaction conditions: wood / liquefaction reagent / sulfuric acid = 3.00/9.00/0.27 gram, at 150 °C. The percentage residues and hydroxyl numbers were determined as an estimate of polyol value of the solution. The PEG system yielded 10–30% residual materials even under the best reaction conditions since low -OH group content resulted to re-condensation of liquefied wood (LW). The hydroxyl numbers linearly decreased from 210 to 100 mg KOH/g on extended (150 min) reaction time. On the other hand, addition of 10% glycerol to the PEG system resulted in small amount of unliquefied residues (~ 3%) and a stable hydroxyl number, regardless of the wood species tested. In case of 60 min reaction time, the mean residue value was 5.8% and a corresponding mean hydroxyl number of 216.1 mg KOH/g was obtained. This system is deemed suitable for liquefaction of a wide variety of wood species.

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