• 농업과학연구
• /
• 제38권1호
• /
• pp.95-100
• /
• 2011

In the present study, effects of autohydrolysis treatment on the properties of rice hull were investigated. Two temperature condition such as $160^{\circ}C$ and $180^{\circ}C$ and thee treatment time such as 15 min, 30 min and 45 min were applied for autohydrolysis treatment. The pH of extract after autohydrolysis treatment decreased as increasing of the temperature and the treatment time. The ash content and the lignin content of rice hull were not decreased by the autohydrolysis treatment. The structure of rice hull after autohydrolysis treatment became more weak, the better efficiency of the fiberization with PFI-Mill was shown for the autohydrolysis treated rice hull with the higher temperature and the longer treatment time.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2008년도 추계학술대회 논문집
• /
• pp.74-76
• /
• 2008

Autohydrolysis at different temperature levels was applied as industrial hemp pretreatment technique for glucose generation. Main structural components removed by autohydrolysis was xylan, which is more sensitive in acidic hydrolysis condition than cellulose or lignin. Higher temperature reaction conditions promoted more biomass components (xylan) removal than lower temperature, which led to better respond to enzymatic saccharification of residual biomass after autohydrolysis. With $185^{\circ}C$ and 60 min, saccharification degree was 53.0% of cellulose in hemp woody core biomass.

• Journal of the Korean Wood Science and Technology
• /
• 제12권4호
• /
• pp.19-30
• /
• 1984

This experiment was carried out to investigate the effects of autohydrolysis and extraction conditions on 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 and retained on 0.25 mm (60 mesh) of Populus alba-glandulosa and Pinus koraiensis were autohydrolyzed with water at $180^{\circ}C$ for 30 and/or 60 minutes in a 6 liter stainless-steel digester with or without 2% 2-naphthol. The hydrothermally-treated wood meals were extracted the lignin with 100%, 90%, 75% and 50% dioxane solutions at $70^{\circ}C$ 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 auto hydrolysis 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-naphthol addition at the autohydrolysis in the digester. 2) After autohydrolysis and lignin extraction 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. 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 alba-glandulosa, the Klason lignin content in cellulosic substrates for 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% or 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 auto hydrolysis 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 Populus alba-glandulosa, the yield of reducing sugars increased with lengthening the autohydrolysis time from 30 minutes to 60 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.

• Journal of the Korean Wood Science and Technology
• /
• 제18권1호
• /
• pp.15-23
• /
• 1990

Roughage feeds were produced from Hyun-aspen (Populus alba $\times$ P. glandulosa) by autohydrolysis. The objectives of this work were to find proper conditions for the treatment of Hyun-aspen by analyzing the compositional change and digestibility and to determine the content of sugar and phenol contained in liquor extracted by digestion. The results of this work were as follows: 1. The proper condition for autohydrolysis of Hyun-aspen chips were $160^{\circ}C$ and 30 minutes in an autoclave. The yield of potential feed from original material and digestibility were 91.3% and 38.9% respectively 2. According to cooking conditions the sugar concentration of extracted solution and the recovery rate of sugar were 0.1~2.5%, 0.3~14.6% respectively. The phenol concentration of extracted solution and the recovery rate of phenol were 0.1~0.3, 0.5~1.8% respectively.

• 한국군사과학기술학회지
• /
• 제15권5호
• /
• pp.699-704
• /
• 2012

In this study, we have proposed a novel decomposition agent composed of Cu(II) and soluble chitosan for organophosphorus chemical agents. Compared to the autohydrolysis, the soluble Cu(II)-Chitosan complex hydrolyzed DFP more effectively. Results show that soluble Cu(II)-Chitosan complex enhances the hydrolysis of DFP in 4~6 folds compared to the autohydrolysis of DFP in buffer solution. This study provides the possibility of using this soluble Cu(II)-Chitosan complex as the environmental friendly decomposition agent which can substitute current DS-2 decomposition agent.

• Journal of the Korean Wood Science and Technology
• /
• 제30권4호
• /
• pp.8-16
• /
• 2002

본 연구는 자기가수분해전처리를 통하여 반응성이 높은 고순도 셀룰로오스기질을 제조하기 위하여 수행되었다. 공시재의 일반 화학조성은 일본잎갈나무와 신갈나무간에 큰 차이가 있음을 알 수 있었다. 추출물함량은 일본잎갈나무가 신갈나무보다 상당량 많았다. 특히 냉·온수 추출물함량은 2.5~3.5배 많았다. 이러한 추출물함량의 큰 차이는 일본잎갈나무에는 arabinogalactan이 많이 함유되어 있기 때문인 것으로 사료된다. 리그닌함량은 신갈나무가 잎갈나무바다 5% 정도 낮았으며, 그 대신 홀로셀룰로오스 및 펜토산함량이 각각3% 정도 높은 값으로 나타났다. 22 kg/cm² 수증기압력에서 5~60분간의 자기가수분해 전처리과정에서 glucose 함량에는 변화가 없었으나, hemicellulose 및 lignin 함량은 급력한 변화를 보였다. 전처리과정에서 가수분해물의 pH는 3까지 저하되었으며, 이러한 경향은 신갈나무 및 일본잎갈나무에서 동일하게 나타났다. Sodium chlorite 및 sulfite 혹은 bisulfite 전처리 후 자기가수분해가 리그닌함량이 낮은 고순도셀룰로오스기질의 제조에 효과적이었다. 특히 자기가수분해처리재를 알칼리 및 산소-알칼리 2단처리함으로서 0~0.2%의 리그닌함량을 가지는 고순도기질을 제조할 수 있었다.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2009년도 춘계학술발표회 논문집
• /
• pp.39-51
• /
• 2009

• Journal of the Korean Wood Science and Technology
• /
• 제17권3호
• /
• pp.45-51
• /
• 1989

A major problem in the enzymatic hydrolysis of lignocellulosic substrates is the very strong bonding of cellulase to lignin and even cellulose in the hydrolysis residues. This phenomenon inhibits recycle of the cellulase which is a major expense of the enzymatic hydrolysis process. In this paper, autohydrolyzed wood was delignified by two-stage with a 0.3% Na OH extraction and oxygen-alkali bleaching and was subjected to enzymatic hydrolysis with cellulase. Also, an improved almost quantitative recycle process of cellulase enzyme was discussed. In enzyme recovery by affinity method. the first recycling showed relatively high hydrolysis rate of 97.4%. Even at the third recycle. hydrolysis rate was 86.7 percents. In the case of cellulase recovery by ultrafiltration method, first 2 recycling treatments resulted very high hydrolysis rate(97.0-97.7%). Even the third recycling showed about 94.2%. Authoydrolysis of oak wood followed by 2-stage delignification with alkali and oxygen-alkali produced a substrate for enzymatic hydrolysis that allowed almost quantitative recycle of cellulase.

• 한국식품영양과학회지
• /
• 제34권6호
• /
• pp.875-879
• /
• 2005

아마인의 linustatin과 neolinustatin은 가수분해되어 acetone, hydrogen cyanide(HCN) 그리고 sugar를 생성하는 diglucoside 시안배당체로써 가수분해물인 HCN의 독성으로 인해 식품의 안전성에 문제가 되고 있다. $80\%$ methanol 추출과 LC/MSn에 의한 정성분석과 RI-LC에 의한 아마인에서 함유된 시안배당체 함량을 조사한 결과, linustatin과 neolinustatin이 각각 평균 206.5 mg/100 g과 174.2 mg/100 g 함유되어 있었다. 또한 autohydrolysis 후 증류액으로부터 IC 분석 에 의 해 HCN 137.38 mg/kg이 가수분해되어 유리됨을 알 수 있었다. 시안배당체의 저감화를 위하여 가열처리를 수행한 결과, 아마인은 $200^{\circ}C$에서 2시간 이상 가열시 $85\%$ 이상의 linustatin과 neolinustatin 그리고 HCN의 제거효과를 보였다. 특히 $200^{\circ}C$에서 30분 가열시 $98\%$의 HCN이 제거됨을 관찰할 수 있었다.

• 펄프종이기술
• /
• 제43권5호
• /
• pp.60-67
• /
• 2011

Hemicelluloses pre-extracted from Korean mixed wood chip were investigated as a wet-end additive. Hemicelluloses dissolved in hot water and alkali solution were isolated by ethyl alcohol precipitation from pre-extractives. They showed molecular weight of 9,000 ~ 27,000 g/mol as revealed by size exclusion chromatography. The reduction of molecular weight through hot water extraction was caused by autohydrolysis. Chemical composition of the hemicelluloses were analyzed with high-performance liquid chromatography and UV-Vis spectroscopy. As the surface charge of isolated hemicelluloses were negative, the adsorption of hemicelluloses onto softwood unbleached kraft pulp fiber was promoted by poly-DADMAC. The physical properties of handsheets increased as the molecular weight of hemicellulose increased. On the other hands, the optical property decreased with hemicellulose adsorption.