著者

李 修京 金 炫佑 石黒 みのり 蔡 光華 袁 立 YI Sookyung KIM Hyunwoo ISHIGURO Minori CAI Guanghua YUAN Li 李 修京(東京学芸大学 外国語・外国文化研究講座 アジア言語・文化研究分野) 金 炫佑(韓国昌原東鎮女子中学校社会科教員。韓国教員大学校大学院博士課程在籍中。) 石黒 みのり(東京学芸大学大学院 連合学校教育学研究科(博士課程)学校教育学専攻 言語文化系教育講座在籍中。) 蔡 光華(東京学芸大学大学院 教育学研究科(修士課程)総合教育開発専攻 国際理解教育コース在籍中。) 袁 立(東京学芸大学大学院 教育学研究科(修士課程)教育支援協働実践開発専攻 教育AI研究プログラム在籍中。)

出版者

東京学芸大学教育実践研究推進本部

雑誌

東京学芸大学紀要. 人文社会科学系. I (ISSN:24349364)

巻号頁・発行日

no.72, pp.73-94, 2021-01-29

著者

Di Guan Rui Zhao Yuan Li Yoshikiyo Sakakibara Masakazu Ike Ken Tokuyasu

出版者

The Japanese Society of Applied Glycoscience

雑誌

Journal of Applied Glycoscience (ISSN:13447882)

巻号頁・発行日

pp.jag.JAG-2018_0006, (Released:2018-11-05)

被引用文献数

5

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Novel bioreactor beads for simultaneous saccharification and fermentation (SSF) of lime-pretreated rice straw (RS) into ethanol were prepared. Genetically modified Saccharomyces cerevisiae cells expressing genes encoding xylose reductase, xylitol dehydrogenase, and xylulokinase were immobilized in calcium alginate beads containing inorganic lightweight filler particles to reduce specific gravity. For SSF experiments, the beads were floated in slurry composed of lime-pretreated RS and enzymes and incubated under CO2 atmosphere to reduce the pH for saccharification and fermentation. Following this reaction, beads were readily picked up from the upper part of the slurry and were directly transferred to the next vessel with slurry. After 240 h of incubation, ethanol production by the beads was equivalent to that by free cells, a trend that was repeated in nine additional runs, with slightly improved ethanol yields. Slurry with pre-saccharified lime-pretreated RS was subjected to SSF with floating beads for 168 h. Although higher cell concentrations in beads resulted in more rapid initial ethanol production rates, with negligible diauxic behavior for glucose and xylose utilization, no improvement in the ethanol yield was observed. A fermentor-scale SSF experiment with floating beads was successfully performed twice, with repeated use of the beads, resulting in the production of 40.0 and 39.7 g/L ethanol. There was no decomposition of the beads during agitation at 60 rpm. Thus, this bioreactor enables reuse of yeast cells for efficient ethanol production by SSF of lignocellulosic feedstock, without the need for instruments for centrifugation or filtration of whole slurry.