• Journal of the Korean Wood Science and Technology
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• 제43권3호
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• pp.355-363
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• 2015

본 연구에서는 초임계 에탄올 및 Ru/C 촉매를 이용하여 초본류 바이오매스 유래 아시안 리그닌을 효과적으로 분해하였으며, 분해 생성된 리그닌오일의 물리화학적 특성을 다양한 분석방법을 이용하여 조사하였다. 리그닌오일의 수율은 반응온도가 $250^{\circ}C$에서 $350^{\circ}C$로 상승함에 따라 89.5 wt%에서 32.1 wt%로 감소하는 경향을 보였지만 분자량 및 다분산지수는 $350^{\circ}C$ 조건에서 아시안 리그닌(3698Da, 2.68) 대비 각각 85%, 44% 감소하여 효과적인 탈중합 반응이 진행되었음을 확인할 수 있었다. 리그닌오일의 GC/MS 분석 결과 guaiacol, 4-ethylphenol, 4-methylguaiacol, syringol, and 4-methysyringol 등 단량체 수준의 페놀화합물은 반응온도가 증가할수록 24.1 mg/g of lignin ($250^{\circ}C$)에서 64.8 mg/g of lignin ($350^{\circ}C$)으로 증가하였으며, 반응기 내부에 수소가스와 촉매(Ru/C)를 첨가하였을 때 최대 76.1 mg/g of lignin 수준까지 향상되는 것을 확인할 수 있었다. 한편 리그닌오일의 원소분석 결과 반응온도가 증가함에 따라 탄소함량은 증가한 반면 산소함량은 점차 감소하였으며, 이를 통해 아시안 리그닌 탈중합 공정 중 수첨탈산소반응 및 수소첨가반응이 진행됨을 간접적으로 확인할 수 있었다.

• 펄프종이기술
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• 제43권3호
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• pp.43-51
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• 2011

Chemical composition and contents of carbohydrates, lignin, and extractives in Moso(Phyllostachys pubescens Mazel), Henon(Phyllostachys nigra var. henonis Stapf ex. Rendle), and Timber bamboo(Phyllostachys bambusoides Sieb. et Zucc.) known as economically valuable bamboo species in Korea were analyzed as a function of ages. All of tested bamboo species were composed of fucose, arabinose, rhamnose, galactose, glucose, xylose, and mannose. Glucose was the sugar which showed the highest content followed by xylose. The contents of others were below 3%. Sugar contents of bamboo shoots showed the lowest among the tested bamboo samples, and the constant rates were shown after 50 days of growth. Lignin content increased by the growth of one year, and the increasing rates tended to be constant after the growth of three years. Bamboo shoots have the highest contents of acid-soluble lignin, which turned into insoluble lignin after the growth of 50 days. Bamboo shoots showed the highest content of extractives and tend to be decreased by the growth of 50 days and then the content increased slowly in proportion to the period of bamboo growth. No relationship was found between species and chemical composition of bamboo. However, there were significant difference in chemical composition between bamboo shoots and 50-day old bamboo.

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

• Journal of the Korean Wood Science and Technology
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• 제52권2호
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• pp.101-117
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• 2024

The conversion characteristics of the major components of Liriodendron tulipifera were investigated during acid-catalyzed organosolv pretreatment. Glucan in L. tulipifera was slowly hydrolyzed, whereas xylan was rapidly hydrolyzed. Simultaneous hydrolysis and degradation of xylan and lignin occurred; however, after complete hydrolysis of xylan at higher temperatures, lignin remained and was not completely degraded or solubilized. These conversion characteristics influence the structural properties of glucan in L. tulipifera. Critical hydrolysis of the crystalline regions in glucan occurred along with rapid hydrolysis of the amorphous regions in xylan and lignin. Breakdown of internal lignin and xylan bonds, along with solubilization of lignin, causes destruction of the lignin-carbohydrate complex. Over a temperature of 160℃, the lignin that remained was coalesced, migrated, and re-deposited on the surface of pretreated solid residue, resulting in a drastic increase in the number and content of lignin droplets. From the results, the characteristic conversions of each constituent and the changes in the structural properties in L. tulipifera effectively improved enzymatic hydrolysis in the range of 140℃-150℃. Therefore, it can be concluded that significant changes in the biomass recalcitrance of L. tulipifera occurred during organosolv pretreatment.

• Korean Chemical Engineering Research
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• 제48권6호
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• pp.704-711
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• 2010

당질계 및 전분질계 바이오 매스(1세대 바이오 매스)의 단점은 식량고갈의 문제로 인한 원료수급이 불안정하여 원료비 상승과 함께 원료 확보라는 문제에 당면해 있다. 이를 해결하기 위한 다양한 대책이 모색되었고 그 대책으로 목질계 바이오 매스(2세대 바이오 매스)에 대한 연구가 이루어져 왔다. 그러나 목질계 바이오 매스는 매우 복잡하고 어려운 Lignin 제거 문제에 직면하게 되었다. 그리하여 현재는 기존의 바이오 매스의 단점을 극복할 새로운 바이오 매스인 비 식용작물의 관심이 증가하고 있다. 비 식용작물 바이오 매스는 당질계 및 전분질계 바이오 매스와 달리 식량문제로 인한 원료비의 상승이나 원료 확보 면에서 안전하며 또한 기존 목질계 바이오 매스에 비해 보다 쉽게 Lignin을 제거할 수 있는 장점이 있다. 본 논문에서는 이러한 비 식용작물 중 Cellulose 함량이 높고 Lignin 함량이 상대적으로 낮은 억새를 이용하여 암모니아 공정 전처리의 최적화 조건을 연구하였다. 공정변수로는 암모니아 농도, 반응시간, 반응온도를 선정하였으며 전처리 후 각 반응물의 Cellulose 함유율, Lignin 함유율, 잔류 고체량 및 가수분해도를 반응표면 분석법을 이용하여 최적 전처리 조건을 확립하였다. 최적조건 탐색 결과는 암모니아 반응농도; 11.27%, 반응온도; $157.75^{\circ}C$, 반응시간; 10.01 min으로 최적 반응조건을 결정할 수 있었으며 최적조건으로 전처리 후 억새의 상대적인 Cellulose 함유율; 39.98%, Lignin 함유율; 8.01%, 가수분해도; 85.89%의 결과를 얻어, 억새가 기존 목질계 바이오 매스들보다 전처리 및 당화 발효에 있어 유리한 기질이라고 결론지을 수 있다.

• 펄프종이기술
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• 제36권5호
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• pp.69-77
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• 2004

Degradations of pine, yellow poplar and sweet gum by two fungi, Pycnoporus cinnabarinus and Trichophyton rubrum LSK-27 were investigated. P. cinabarinus degraded pine block samples much faster than T rub rum LSK-27, whereas P. cinnabarinus and T rubrum LSK-27 degraded yellow poplar and sweet gum at almost the same rate. In an effort to get a better understanding of how fungi degrade lignin in wood, contents of various functional groups were analyzed. After three-months of degradation of pine flour by these fungi, the following changes were observed: an increase in condensed phenolic OH group and carboxylic acid group content, a decrease in the guaiacyl phenolic OH content, and little change of aliphatic OH group content. Further studies in the degradation of pine flour by P. cinnabarinus indicated that the increase in condensed phenolic OH group content and the decrease in guaiacyl phenolic OH group content occurred in the first month of the degradation. The changes of functional group contents in the degradation of unbleached softwood kraft pulp by P. cinnabarinus had the same trends as those in the degradation of pine flour. That is, structural alteration of lignin due to the kraft pulping process had little effect on how P. cinnabarinus degraded lignin.

• 아시안잔디학회지
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• 제4권2호
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• pp.119-123
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• 1990

The experiment was carried out to analysis the differences between classification by the estimate of survey character and thatch accumulation. The results obtained are summarized as follows:1.BentgrassPenncross: had the highest thatch accumulation. 2.Thatch accumulation of creeping season turf was higher than that of bunch type and thatch accumulation of cool season turf was higher than that of warm season turf. 3.The coverage rate was 43.3%, so turf quality was not good. 4.Bermudagrass(Guymon) had the highest content of lignin in thatch and coverage rate. 5.Species had significant negative correlation with the content of lignin.

• Journal of the Korean Wood Science and Technology
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• 제40권2호
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• pp.78-90
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• 2012

Soybean hull is an attractive feedstock for glucose production. To increase the glucose conversion in acid hydrolysis, a pretreatment method combined steam explosion with alkali pretreatment for soybean hull was studied. For first step pretreatment, steam explosion conditions (log Ro 2.45) were optimized to obtain maximum solid recovery and cellulose content. In the second step pretreatment, the conditions for potassium hydroxide pretreatment of steam exploded soybean hull were optimized by using RSM (response surface methodology). The optimum conditions for minimum lignin content were determined to be 0.6% potassium hydroxide concentration, $70^{\circ}C$ reaction temperature and 198 min reaction time. The predicted lignin content was 2.2% at the optimum conditions. Experimental verification of the optimum conditions gave the lignin content in similar value with the estimated value of the model. Finally, glucose conversion of pretreated soybean hull using acid hydrolysis resulted in $97.1{\pm}0.4%$. This research of two-step pretreatment was a promising method for increasing the glucose conversion in the cellulose-to-glucose process.

• Journal of Ginseng Research
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• 제8권2호
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• pp.91-104
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• 1984

This study was conducted to investigate the characteristics of nonstarchy polysaccharides in Korean ginseng, (Panax ginseng C.A. Meyer). The results obtained are as follows. 1. The total sugar content of ginseng roots were decreased with increasing the cultural period. On the other hand, the crude fiber content was increased with that of the ginseng leaves or stems. But the crude fiber in root was much less than that of leaves and stems. 2. The dietary fiber content of ginseng root on 5 years old was 14.20% as neutral detergent fiber, 9.08% as acid detergent fiber, hemicellulose 5.12%, cellulose 7.98% and lignin of 1.10%, respectively. 3. Much more pectin was found in ginseng roots which was cultivated for shooter Period. And it was contained much more in the root than in the leaves and stems. 4. ginseng hemicellulose content in root was 5% to 10%. It was decreased with increasing: cultivated period. Hemicellulose was constituted of xylose, arabinose, glucose, rhamnose and xylose of these sugars was the predominant. 5. X-ray diffraction Pattern of ginseng cellulose showed maximum intensity at tile interplanar angle of 4.1$^{\circ}$.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2004년도 춘계 학술대회지
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• pp.160-161
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• 2004