• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.253-253
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• 2010

Rice straw was pretreated with aqueous ammonia in order to enhance enzyme digestibility. Soaking in ammonia aqueous (SAA) was conducted with 15% ammonia, at $60^{\circ}C$. for 24 h. Optimization of both saccharification conditions and enzyme loading of SAA rice straw was carried out. Especially enzyme loading test was performed using statistical method. Moreover proton beam irradiation (PBI) was also performed to overcome the problem which inhibit the enzyme digestibility at 1-25 kGy doses with 45 MeV of beam energy. Optimal condition for enzymatic saccharification was follows; pH 4.8, $50^{\circ}C$, 60 FPU of enzyme activity, 1:4 ratio of celluase and ${\beta}$-glucosidase. Also, optimal doses of PBI on rice straw and SAA-treated rice straw for efficient sugar recovery were found to be 3 kGy, respectively. When saccharification was performed with optimal condition, glucose conversion yield was 89% of theocratical maximum in 48 h, and 3 kGy of PBI was applied to SAA-treated rice straw, approximately 90% of the theoretical glucose yield was obtained in 12 h. The results of X-ray diffractometry (XRD) support the effect of both SAA and PBI on sugar recovery, and scanning electron microscopy (SEM) images unveiled the physical change of the rice straw surface since rugged rice straw surface was observed.

• Applied Biological Chemistry
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• 제32권4호
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• pp.374-377
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• 1989

생전분 분해효소에 의한 전분의 당화에서 유리구를 첨가시켜 회전진탕시키므로 당화시간의 단축과 당화율의 증대에 효과가 있었다. 옥수수전분과 유리구의 중량비를 1 : 5로 하여 Streptomyces sp. 4M-2의 ${\alpha}-amylase$를 첨가하고 300rpm으로 교반시켰을 때 30시간 후에 88%, 감자전분에서 69%의 당화율을 나타냈다. 옥수수전분에서 amyloglucosidase를 병용하였을 때는 6시간 후에 88%의 당화율을 보였다.

• Food Science and Biotechnology
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• 제16권3호
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• pp.381-385
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• 2007

The objective of this experiment was to study the influence of feed moisture content on the degree of enzymatic hydrolysis of com starch in a twin screw extruder and the saccharification yield of the dried extrudate. The feed moisture content was set at 25, 30, and 35% and ${\alpha}$-amylase solution was directly injected into the feed section at a barrel temperature of $95^{\circ}C$ and screw speed of 250 rpm. Amyloglucosidase was used for the saccharification of the dried extrudate at a concentration of 0.055%(w/w). Expansion ratio and swelling factor of extrudates decreased with increasing the feed moisture content. Addition of ${\alpha}$-amylase during extrusion process raised reducing sugar content of extrudates which also increased with the feed moisture content. The saccharification yield of dried extrudate was higher for the extrudate with lower feed moisture content.

• Journal of Microbiology and Biotechnology
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• 제29권11호
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• pp.1760-1768
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• 2019

The use of lignocellulosic biomass such as rice straw can help subsidize the cost of producing value-added chemicals. However, inhibitory compounds, such as phenolics, produced during the pre-treatment of biomass, hamper the saccharification process. Laccase and electrochemical stimuli are both well known to reduce phenolic compounds. Therefore, in this study, we implemented a bioelectrochemical detoxification system (BEDS), a consolidated electrochemical and enzymatic process involving laccase, to enhance the detoxification of phenolics, and thus achieve a higher saccharification efficiency. Saccharification of pretreated rice straw using BEDS at 1.5 V showed 90% phenolic reduction (Ph_r), thereby resulting in a maximum saccharification yield of 85%. In addition, the specific power consumption when using BEDS (2.2 W/Kg Ph_r) was noted to be 24% lower than by the electrochemical process alone (2.89 W/kg Ph_r). To the best of our knowledge, this is the first study to implement BEDS for reduction of phenolic compounds in pretreated biomass.

• Journal of the Korean Wood Science and Technology
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• 제48권3호
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• pp.405-413
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• 2020

Recycling of ionic liquid (1-ethyl-3-methylimidazolium acetate, [EMIM]Ac) after the pretreatment of Salix gracilistyla Miq. was conducted and the effect of the recycling number on the enzymatic saccharification yield was investigated. Enzymatic saccharification was performed using an enzyme cocktail (Acremonium cellulase and Optimash BG) at 50 ℃ for 72 h. All recycled [EMIM]Ac samples showed a lower amount of water soluble fraction than pure [EMIM]Ac. On increasing the recycling number from 1 to 4, the amount of water soluble fraction decreased from 18% to 15%. The X-ray diffraction pattern of the products pretreated with recycled [EMIM]Ac showed cellulose I crystalline polymorph. The crystallinity of the product pretreated with recycled [EMIM]Ac was 47-49%, which was lower than 33% of that with pure [EMIM]Ac. The yields of glucose and xylose decreased in the pretreatment with recycled [EMIM]Ac compared to that with pure [EMIM]Ac.

• Preventive Nutrition and Food Science
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• 제11권4호
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• pp.318-322
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• 2006

The objective of this experiment was to investigate the effect of extrusion of ginseng roots in twin screw extruder on susceptibility of ginseng starch toward hydrolysis by ${\alpha}-amylase$ BAN 480L (Novozyme, Denmark) and cellulase Celluclast 150L and saccharification by amyloglucosidase AMG-E (Novozyme, Denmark). The extrusion was conducted at 22% and 30% moisture contents of feed at screw speed 300 rpm. Barrel temperature at zone 1 was adjusted at $100^{\circ}C$ and $120^{\circ}C$. The results showed that extrusion process improved the ginseng ${\alpha}-amylase$ susceptibility as compared to traditionally dried ginseng (white and red ginseng). Reducing sugar of hydrolyzed extruded samples was 2,500% of its initial concentration, whereas the reducing sugar of hydrolyzed non-extruded sample was only 200% of its initial concentration. However, addition of cellulase during liquefaction lowered the saccharification yield of both non-extruded and extruded samples as well.

• 한국식품저장유통학회지
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• 제14권6호
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• pp.650-654
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• 2007

식혜 고유의 시원한 맛과 인삼의 독특한 맛을 가미한 인삼식혜를 제조하기 위해 본 연구에서는 엿기름 20 g, 고두밥 400 g을 기준으로 하여 여기에 각 인삼분말을 고두밥양의 $3{\sim}12%$, teramyl효소 0.2 mL을 각각 첨가한 후 인삼식혜 제조에 있어 당화공정의 특성을 분석하였다. 인삼식혜의 당화공정은 일반 식혜의 당화공정과 같이 당화 온도 및 당화 시간이 증가할수록 당화력이 증가 하는 경향을 보였다. 하지만 본 실험에서 제조한 인삼식혜의 유리당 분석을 한 결과 식혜고유의 주성분인 말토오스 함량이 일반 식혜보다 훨씬 높은 4.3%이상의 농도를 나타내고 있어 시판식혜에 비해 우수한 품질의 특성을 보였다.

• Journal of the Korean Wood Science and Technology
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• 제45권2호
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• pp.232-242
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• 2017

The objective of this study was to examine changes in the porosity and internal structure of wood as it goes through the process of saccharification (extraction of fermentable sugars). This study also examined the use of different drying methods to prepare samples for characterization of internal pores, with particular emphasis on the partially disrupted cell wall. Aspen wood flour samples after dilute acid pretreatment followed by enzymatic hydrolysis were examined for nitrogen adsorption. The resulting isotherms were analyzed for surface area, pore size distribution, and total pore volume. Results showed that freeze drying (with sample pre-freezing) maintains the cell wall structure, allowing for examination of saccharification effects. Acid pretreatment (hemicellulose removal) doubled the surface area and tripled the total volume of pores, which were mostly 10-20 nm wide. Subsequent enzymatic hydrolysis (cellulose removal) caused a 5-fold increase in the surface area and a ~ 11-fold increase in the total volume of pores, which ranged from 5 to 100 nm in width. These results indicate that nitrogen adsorption analysis is a feasible technique to examine the internal pore structure of lignocellulosic residues after saccharification. The information on the pore structure will be useful when considering value-adding options for utilizing the solid waste for biofuel production.

• Journal of Microbiology and Biotechnology
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• 제30권12호
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• pp.1912-1918
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• 2020

Hyper-thermal (HT) acid hydrolysis of red seaweed Gelidium amansii was performed using 12% (w/v) slurry and an acid mix concentration of 180 mM at 150℃ for 10 min. Enzymatic saccharification when using a combination of Celluclast 1.5 L and CTec2 at a dose of 16 U/ml led to the production of 12.0 g/l of reducing sugar with an efficiency of enzymatic saccharification of 13.2%. After the enzymatic saccharification, 2,3-butanediol (2,3-BD) fermentation was carried out using an engineered S. cerevisiae strain. The use of HT acid-hydrolyzed medium with 1.9 g/l of 5-hydroxymethylfurfural showed a reduction in the lag time from 48 to 24 h. The 2,3-BD concentration and yield coefficient at 72 h were 14.8 g/l and 0.30, respectively. Therefore, HT acid hydrolysis and the use of the engineered S. cerevisiae strain can enhance the overall 2,3-BD yields from G. amansii seaweed.

• 한국조리학회지
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• 제18권2호
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• pp.206-215
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• 2012

본 연구에서 오디를 첨가하여 당화와 식혜의 미치는 영향에 대한 결과는 다음과 같다. 당화기간 동안의 pH의 변화는 오디의 첨가량이 증가할수록 pH는 감소하였으며 당화 4시간 이후에는 큰 변화를 보이지 않았다. $^{\circ}Brix$는 4시간까지는 매시간 1 $^{\circ}Brix$이상 증가하고, 4시간 이후는 변화폭이 1 $^{\circ}Brix$이하로 감소하여 당화시간은 4-5시간이 적당한 것으로 보여진다. 오디 식혜의 색도는 L 값은 감소하고 a 값과 b 값은 증가하였고 오디 식혜의 DPPH free radical 소거활성과 SOD 유사활성은 오디의 첨가량이 증가할수록 증가하였으며, 오디의 anthocynin색소에 미생물 억제 효과가 있으며 오디 식혜의 기호도는 10% < 30% < 15% < 20% < 0% < 25% 이었고 오디의 첨가량은 10% 초과 25% 이하가 바람직한 것으로 보여 지며 오디의 첨가량이 증가할수록 오디 식혜의 당도는 증가하여 오디의 첨가는 식혜의 설탕 사용량을 감소시킬 것으로 보여 지며 제품의 색깔과 산미를 부여하여 기호를 증진시킬 것으로 사료된다.