Using fresh water diatom, identified as Melosira variance which is growing faster than other algae in the ponds, we characterized the ultrastructure of its silica frustule by electron microscopic observations. On hypothesizing that the ultrastructure has some meanings in photosynthesis, behaviors of a single frustule toward light irradiation were analyzed using an optical fiber. We found that the frustule absorbed light mainly in the blue wavelength region. The theoretical analyses of optical properties supported experimental results and suggested a strong interaction between blue light and inner silica materials. It is speculated that the interaction served for partial extinction of excessive irradiation of blue light and for enhancing photosynthesis of the diatom.

Rapidly dried onion (Allium cepa L. cv. Momiji No. 3) powder (OP) prepared from the outer layers (from second to fourth scale leaves from the surface) of onion bulbs was analysed for quercetin and polyuronide contents, the effects of enzymatic treatment and the anti-atherogenic effect on rats fed a high-fat diet. Quercetin 4′-glucoside (50%), free quercetin (30%) and quercetin 3,4′-diglucoside (20%) were identified as quercetin derivatives, and boiling-water extraction was effective in extracting these compounds.OP contained 12.9% of polyuronides, the basic skeleton of pectin. Enzymatic degradation (cellulase and pectinase, 50 °C for 12 h, pH 6.0) of OP was effective in obtaining a slurry of smaller particle sizes. Free quercetin increased and the glucosides decreased with enzyme treatment. In Wistar rats fed an OP-added high-fat diet, total cholesterol, HDL-cholesterol and triglyceride concentrations were not significantly different from rats fed a high-fat diet without OP. However, the atherogenic index (AI) of Wistar rats fed an OP-added high-fat diet was lower (AI = 3.3) than rats fed the diet without OP (AI = 4.1). The incremental elastic modulus (IEM) of the aorta from rats fed the OP-added diet was also significantly lower than rats fed the diet without OP. The AI and IEM values of rats fed the OP-added diet were quite similar to the values of rats fed the diet without OP but allowed spontaneous exercise. These results suggest that OP intake is effective for decreasing the risk of arteriosclerosis.

The direct electrospinning of a non‐derivatized cellulose (Cs)–chitosan (Ch) composite nanofiber is described for the first time. Either of two cellulose preparations from different sources, i.e., cotton (CsC) or bamboo (CsB), is fabricated into composite electrospun non‐woven fabrics (ESNWs) with Ch using the trifluoroacetic acid–acetic acid mixed solvent. The total concentration of Cs + Ch in the mixed solvent is fixed at 4.0 wt.‐% with various Cs/Ch weight ratios of 8:2, 5:5 (Figure shows CsB/Ch‐ESNW), and 2:8, which are fabricated into fine fibers in the Cs/Ch‐ESNWs having average diameters mostly <100 nm. The treatment of the composite fibers with an alkaline–alcohol solution produces the water‐resistant ESNWs, which can retain their fine fibrous network in aqueous environments.

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