成果報告書詳細
管理番号100013036
タイトル*平成19年度中間年報 新エネルギー技術研究開発 バイオマスエネルギー高効率転換技術開発(先導技術研究開発)未利用木質バイオマス(樹皮)の高効率糖化先導技術の開発
公開日2009/4/24
報告書年度2007 - 2007
委託先名国立大学法人名古屋大学
プロジェクト番号P07015
部署名新エネルギー技術開発部
和文要約以下本編抜粋:1.研究開発の内容及び成果等樹皮糖化に適したオーダーメード麹菌による画期的な酵素糖化技術、および高効率で(酸・酵素)糖化可能なバイオマス資源樹木の育種技術を開発することとし、以下の4点から事業を推進した。樹皮の酵素糖化技術の開発1)目的樹皮の化学成分分析を行い、化学成分からの酵素糖化性について検討する。また、酵素糖化性に優れた酵素前処理技術の開発についても検討を行う。2)方法及び結果1化学成分分析樹皮をカッティングミルにて粉砕し、粒度の違いにより3フラクションに分画した。化学成分分析の結果、ユーカリ樹皮はスギ樹皮に比べホロセルロース量およびα-セルロース量が多く、クラーソンリグニン量が少ないため、糖化に有用な試料であると期待された。また、ユーカリ内樹皮の80メッシュ以下のフラクションには、60%以上のシュウ酸カルシュウムが含まれており、全体でも24.6%と多量に含有していることが分かった。
英文要約Development of Enzymatic Saccharification of Bark The aim of the current research is to establish the basis for enzymatic saccharification of Eucalyptus and Sugi bark. It was found that Eucalyptus inner bark is adequate sample for saccharification because of high hemicellulose and low klason lignin content. Eucalyptus inner bark has much amount of calcium oxalate. To improve the enzyme saccharification, we investigated the pretreatment method and found that hydrothermal reaction with carbon dioxide was very effective procedure for Eucalyptus inner bark. In this system, about 404 kg of sugar will be obtained from 1 kg of Eucalyptus inner bark, which suggests 232 L of ethanol will be yielded by fermentation. This system, however, does not suit for Sugi inner bark. Aspergillus oryzae XlnR overproducer (HXlnR) possessed extremely enhanced productivity of xylanolytic and celllulolytic enzymes when compared to the wild type. But attempts to degrade raw Eucalyptus bark with the HXlnR enzyme mixture were not very successful. Considering composition of plant cell wall, effect on the degradation by cellulase, pectinase, and mannanase addition was examined. Pectinase was crucial, and cellulase addition enhanced the degradation. Major components of the HXlnR enzyme mixture were assigned to be endoxylanases XynF1, XynF3, XynG1, and XynG2, a feruloyl esterase FaeA, an acetylxylan esterase AxeA, a novel endoglucanase, and a cellobiohydrolase CelC. Cellulolytic activity was approximately 30 times lower than xylanolytic activity. No pectinase was found. Therefore, enhancement of pectinase and cellulase activity in HXlnR is required to develop A. oryzae with strong degradation activity of the raw bark. Aiming to enhance cellulolytic activity of HXlnR, Trichoderma reesei cbh1 and cbh2 were fused to the xynF1 promoter and introduced into HXlnR. The transformants produced several times higher cellobiohydrolase activity than HXlnR. Further improvement of cellulolytic activity may be achieved by simultaneous introduction of cbh1 and cbh2 and by enhancement of endoglucanase activity. Breeding Trees Suitable for Highly-efficient Saccharification The saccharification yield measurement system was examined to evaluate the variation of the saccharification difficulty, the evaluation system was established, and the evaluation began. The 78 barks of Cryptomeria japonica in domestic various places had been collectedand the variation of the saccharification difficulty was confirmed. As a result, the saccharification yield of inner-bark variation is concerned in reserve starch. But outer-bark variation is concerned in amount glucose from secondary wall cellulose. Research on Saccharification Process of Bark with Aspergillus Enzymes Inner bark of Eucalyptus globulus was pretreated with hot CO2 water and observed under a scanning electron microscope and a transmission electron microscope.
ダウンロード成果報告書データベース(ユーザ登録必須)から、ダウンロードしてください。

▲トップに戻る