• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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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.

• Korean Chemical Engineering Research
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• v.56 no.4
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• pp.542-546
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• 2018

In this study, the effects of malonic acid-catalyzed pretreatment on the subsequent enzymatic hydrolysis of red macro-algae Gracilaria verrucosa for production of biosugar (total reducing sugar) were investigated. In the hydrothermal pretreatment condition of 300 mM malonic acid, 1:20 solid-to-liquid ratio at $130^{\circ}C$ for 60 min, a 49.2% biosugar yield was achieved. Moreover, by subsequent enzymatic hydrolysis after pretreatment, maximum yield of 64.5% was achieved.

• Journal of Applied Biological Chemistry
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• v.56 no.4
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• pp.245-247
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• 2013

The potential of the red ginseng marc (RGM) for the production of bio-ethanol using enzymatic hydrolysis and fermentation without any additional nutrients was investigated. Reducing sugar content in RGM treated with Viscozyme and Flavourzyme was 101.1 g/L and was much higher than that (7.2 g/L) in intact RGM. When enzymatically hydrolyzed red ginseng marc (ERGM) was fermented with commercially available dry yeast at $25^{\circ}C$ for 7 days, the final ethanol concentration reached 29.3 g/L with ethanol yield at 0.274 g of ethanol per 1 g of solubilized total sugar. Ethanol concentration and ethanol yield of ERGM were drastically increased over 1000% and 50%, respectively than those of RGM.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.1
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• pp.85-90
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• 2005

A downstream process was developed for the production of yeast extract from brewer's yeast cells. Various downstream processing conditions including clarification, debittering, and the Maillard reaction were considered in the development of the process. This simple and economic clarification process used flocculating agents, specifically calcium chloride ($1\%$). After the clarification step, a Maillard reaction is initiated as a flavor-enhancing step. By investigating the effects of several operation parameters, including the type of sugar added, sugar dosage, glycine addition, and temperature, on the degree of browning (DB), giucose addition and reaction temperature were found to have significant effects on DB. A synthetic adsorption resin (HP20) was used for the debittering process, which induced a compositional change of the hydrophobic amino acids in the yeast hydrolysate, thereby reducing the bitter taste. The overall dry matter yield and protein yield for the entire process, including the downstream process proposed for the production of brewer's yeast extract were 50 and $50\%$, respectively.

• Preventive Nutrition and Food Science
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• v.11 no.4
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• pp.261-267
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• 2006

This study investigated the physiological activities of different molecular weight (MW) fractions of crude polysaccharide from $D\check{o}d\check{o}k$ (Codonopsis lanceolata). The crude polysaccharide cut off for each fraction was: <1,000 MW (Fr I), 1,000 MW

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.1
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• pp.9-13
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• 1986

An experiment on strawberry (Fragaria Grandflora EHRH) was conducted in order to compare the effect of two compound fertilizers made for this crop, by Kyonggi Chemical Crop. LTD. with that of muriate of potash, sulfate of potash and ammonium nitrate in a farmer's vinylhouse during the winter period of 1984 to 1985. Results obtained are as follows; 1. The effect of compound fertilizers on the growth, number of inflorescences and yield of strawberry showed no significant difference from the effect of muriate of potash, sulfate of potash and ammonium nitrate. But the former increased the content of reduced, and total sugars soluble in diluted acid in the juice of strawberry. 2. As a whole, sulfate of potash increased sugar content in strawberry juice more than muriate of potash, which became the reason to increase the sugar content in the strawberry juice harvested from the compound fertilizer plots.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.1
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• pp.31-38
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• 2019

This study was carried out to investigate the growth characteristics, yield, and chemical compositions of winter forage crops cultivated after rice harvest in the central inland region. The experimental design was arranged in a randomized block design with three replications. The treatments consisted of 4 species (Rye, Oat, Triticale and Italian ryegrass), and varieties were "Marton", "Donghan", "Shinyoung" and "Kowinnearly", respectively. As a result, dry matter yield and TDN yield were higher in rye than in the other winter forage crops, and lowest in Oat(p<0.05). Crude protein and crude fat content were significantly higher in Italian ryegrass(p<0.05). However, Crude ash and ADF content did not show significant difference among winter forage crops. NDF content was higher in order of Rye > Triticale > Oat > Italian ryegrass(p<0.05). TDN and total amino acid content (EAA+NEAA) were higher in order of winter forage crop with high crude protein content (Italian ryegrass > Oat > Triticale > Rye). Total mineral content was higher in order of Rye > Triticale > Oat > Italian ryegrass(p<0.05), and total free sugar content was higher in order of Oat > Italian Ryegrass > Triticale > Rye(p<0.05). Compared with the results above, Italian ryegrass and Oat are high in crude protein, TDN, amino acid and free sugar content. Rye and Triticale have the merit that feed value is decreased but high yield(dry matter and TDN yield) can be maintained. Therefore, it is advantageous to grow Rye and Triticale as winter forage crops after rice harvest in the central inland region.

• Journal of the Korean Society of Food Culture
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• v.31 no.4
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• pp.348-356
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• 2016

The purpose of this study was to investigate the chemical contents (sugar, nitrogen, and amino acids) and sensory characteristics of traditional soy sauce according to three different methods. The samples were taken from four different periods (0, 20, 40, and 60 days after fermentation). Total sugar contents increased in all groups according to ripening period, and Gyupjang (G) showed the highest sugar content among the groups. Total nitrogen and amino acid contents of all groups increased after 60 days of ripening, and Gyupjang (G) and Gyupjang mixed with salt water (SG) had higher total nitrogen content compared to Chungjang (S) at the same period. The results from the sensory evaluation show that preferable sensory characteristics, such as color preferences, sweetness, umami taste, and overall preference, were significantly higher in Gyupjang (G) and Gyupjang mixed with salt water (SG) than in Chungjang (S). Preferable sensory characteristics had significantly high positive correlation with most amino acids, total nitrogen, and sugar contents, except for glutamine. Based on the significant difference in preferable sensory characteristics between Gyupjang mixed with salt water (SG) and Chungjang (S), Gyupjang mixed with salt water (SG) can be used to improve sensory characteristics. This research implies that adding salt water during the manufacturing Gyupjang process is advisable to yield high quality soy sauce.

• The Korean Journal of Community Living Science
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• v.22 no.4
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• pp.549-556
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• 2011

The objective of this study was to develop a food material and, examination of fermented juice using turnips. The highest yield of fermented juice was with the mixture ratio of 60% turnip, 20% rice-nuruk and 20% sugar. The total acidity and turbidity increased depending on the adding rate of rice-nuruk. By reducing sugar concentration by 24.9%, 22.6% and 25.3% resulted in samples containing 5%, 20% and 35% of rice-nuruk. The reduced sugar concentration was the highest at 35% rice-nuruk and 5% sugar. As a result of enzyme activity, ${\alpha}$-amylaze was the highest at 5% rice-nuruk and 35% sugar, and glucoamylase was increased by depending on the rice-nuruk concentration. The main organic acids in fermented turnip juice were succinic acid, acetic acid and lactic acid, and were increased during fermentation. DPPH free radical scavenging activity of fermented turnip juice was higher than that of non fermented turnip juice. Also, the nitrite scavenging ability was the highest($89.58{\pm}0.00$) in 35% rice-nuruk at pH 3.0.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.70-74
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• 2016

In this study, the effects of citrate buffer pretreatment conditions (solid-to-liquid ratio, reaction temperature, pH and concentration of buffer) on enzymatic hydrolysis of E. intestinalis for total reducing sugar (TRS) production were investigated. As a results of the citrate buffer pretreatment, a 5.40% hydrolysis yield was obtained under conditions including 1:10 solid-to-liquid ratio, 0.25 M citrate buffer (pH 3.5) at $140^{\circ}C$ for 60 min. The maximum hydrolysis yield of 18.68% was obtained to enzymatic hydrolysis after pretreatment. This result is 1.81 times higher than that of control.