목분의 Autohydrolysis 후 탈리그닌처리가 섬유소기질의 수율 , 리그닌함량과 효소가수분해에 미치는 영향 = Effect of Delignification Treatment after Autohydrolysis on Yields of Cellulosic Substrates , Lignin Contents , and Enzymatic Hydrolysis

다국어 초록 (Multilingual Abstract)

This experiment was carried out to investigate the effects of autohydrolysis and extraction conditions an the separation of the chemical substances, the extractability of lignin by dioxane, and the yield of reducing sugars from cellulosic substrates by using a commercial cellulase derived from Trichoderma viride. Air-dried wood meals through 0.42mm (40 mesh) screen ant retained an 0.25 mm (60 mesh) of Populus alba.glandulosa and Pinus koraiensis were autohydrolyzed with water at 180℃ for 30 and/or 60 minutes in a 6 liter stainless-steel digester with or without 2% 2-naphthol. The hydtothermally-treated wood meals were extracted the lignin with 100%, 90%, 75% and 50% dioxane solutions at 70℃ for 4 hours, respectively. The results obtained were as follows: 1) After autohydrolysis of Populus alba-glandulosa, the yield of wood meals decreased with lengthening the autohydrolysis time from 30 minutes to 60 minutes and with 2% 2-naphthol addition. In case of Pinus koraiensis, the yield was not affected by 2%, 2-naphthal addition at the autahydrolysis in the digester. 2) After autohydrolysis and lignin extraction of Populus adba-glandulosa, the yield of wood meals decreased with lengthening the autohydrolysis time from 30 minutes to 60 minutes and with 2% 2-naphthol addition. Extraction of 50% dioxane solution was the best solvent for the yield among the solutions of 100%, 90%, 75% and 50% dioxane. In case of Pinus koraiensis, the yield was not affected by 2% 2-naphthol addition and the solution of 90% dioxane was the poorest solvent for the yield. 3) After autohydrolysis and lignin extraction of Populus adba-glandulosa, the Klason lignin content in cellulosic substrates far enzymatic hydrolysis decreased with lengthening the autohydrolysis time from 30 minutes to 60 minutes and with 2% 2-naphthol addition. Klason lignin content was the lowest after extraction by 90%r of 75% dioxane solution. The content was also affected by interaction of the three factors-autohydrolysis time, 2% 2-naphthol addition and concentration of dioxane. In case of Pinus koraiensis, the Klason lignin content increased with 2% 2-naphthol addition but was not affected by the concentration of dioxane solution. 4) After autohydrolysis and lignin extraction of Populus alba-glandulosa, the extractable Klason lignin content by extraction increased with lengthening the autohydrolysis time from 30 minutes to 60 minutes and with 2% 2-naphthol addition. The extractable lignin content was the highest after extraction by 90% or 75% dioxane solution. In case of Pinus koraiensis, the extractable lignin content increased with 2% 2-naphthol addition. Extractions by 100%, 90% and 50% dioxane solutions were more effective for the extraction of Klason lignin than by 75% dioxane solution. 5) After autohydrolysis and lignin extraction of Populu.s alba-glandulosa, the yield of reducing sugars increased with lengthening the autohydrolysis time from 30 minutes to 50 minutes but was not affected by 2% 2-naphthol addition and the concentration of dioxane. The yield of reducing sugars after enzymatic hydrolysis was slightly higher by extractions with 90%, 75% and 50% dioxane solutions than with 100% dioxane. In case of Pinus koraiensis, the yield of reducing sugars was not affected by 2% 2-naphthol addition but affected by the concentration of dioxane. The yield of reducing sugars was the highest in cellulosic substrates extracted by 100% dioxane solution.