3 research outputs found
Silk protein of the larval caddisfly, Sienopsyche marmorata (trichoptera: stenopsychidae)(trichoptera: stenopsychidae)
Stenopsyche marmorata is one of the common caddisfly species inrivers and streamsin Japan which is distributed in East Palaearctic Region・ The larvae spin Silk fiber between stones on the bottom of Bowing water, the silk proteinofS・ marmorata would be one of the best sources of natural biopolymersthat could be used as materials for aquatic industrial purposes・ In order to analyze the basic characteristics towards further applications, we measured physical properties, thermal behaviorsand molecular confわrmation of the silk protein of larval S marmorata・ The wet weight of the larval body andthe silkgland of SOrata Were 543・5土5419and 44・7土17・9 mg, respectively, The water content of the liquid silk protein in the silkglands of the living larvae was 73.4土2.2%. The elongation atthe breaking point of the solid silk proteingland in dry state was 2・2%, whilethat of sampleinwet state was・ 6012%, suggestlngthe silk protein glands become soft and stretchable in wet conditions. FT-IR spectra of the silk protein film showed a major absorption band at 1650 cm-1 (Amide I band), which is attributed to the random coil molecular conformation. The silk fiber showed a major endothemiCpeak at 32loC onthe differential scanning calorimetry (DSC) curve, which position is slightly higher than the endothemic peak for the silk film, Suggesting an increaseinthe thermal stabilityfbr the silk fiber from caddisfly,Article信州大学山地水環境教育研究センター研究報告 6: 1-8(2010)departmental bulletin pape