Biomass has been considered as an alternative feedstock for energy and material supply. However, the lack of high-efficiency and low-cost processes for biomass utilization and conversion hinders its large-scale application. This report describes electrochemical hydrogen production from waste biomass that does not require large amounts of energy or high production costs. Hydrogen was produced by the electrolysis of bread residue, cypress sawdust, and rice chaff at an onset cell voltage of ca. 0.3 V, with high current efficiencies of approximately 100% for hydrogen production at the cathode and approximately 90% for carbon dioxide production at the anode. The hydrogen yields per 1 mg of the raw material were 0.1−0.2 mg for all tested fuels. Electrolysis proceeded continuously at plateau voltages that were proportional to the current. These characteristics were attributable to the high catalytic activity of the carbonyl-group functionalized mesoporous carbon for the anode reaction, and that the major components of biomass such as cellulose, starch, lignin, protein, and lipid were effectively utilized as fuels for hydrogen production.

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Naturally occurring fraxin (1) was administered orally to rats to investigate its metabolism. Urinary metabolites were analyzed by three-dimensional HPLC, and fraxetin-7-O-sulfate (2), fraxetin-7-O-beta-glucuronide (3), fraxetin (4), 6,7,8-trihydroxycoumarin (5), and fraxidin (6) were isolated. Fraxin (1) was extensively metabolized to 4, which was partly metabolized to 5 in a rat fecal suspension after incubation for 24 h. Urinary excretion of 4 and 5 in rats administered orally with 1 was substantially reduced when the rats were treated with antibiotics to suppress their intestinal flora. Incubation of 1 with a rat liver S-9 mixture yielded 6. These results suggest that hydrolysis and demethylation of 1 are performed by intestinal microflora, while methylation occurs in the liver.

Stagnation of peripheral blood ‰ow is the cause of various diseases. Changes in peripheral blood ‰ow after oral administration of Kampo medicines in mice with betamethasone-induced oketsu syndrome and normal mice were examined using a laser Doppler blood ‰ow meter. The Kampo medicines used were: Toki-shakuyaku-san; Kami-shoyosan; Keishi-bukuryo-gan; Daio-botanpi-to; Tokaku-joki-to; Goshuyu-to; and Hange-koboku-to. In the oketsu mice, blood ‰ow was improved by single-dose administration of Toki-shakuyaku-san, Kami-shoyo-san, Keishi-bukuryo-gan, Daio-botanpi-to, Tokaku-joki-to, and Goshuyu-to, but only Toki-shakuyaku-san increased blood ‰ow signiˆcantly in normal mice. In addition, blood ‰ow decreased after single-dose administration of Keishi-bukuryo-gan, Daio-botanpito, and Tokaku-joki-to in normal mice.