• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.525-528
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• 2006

아임계 및 초임계수에 의한 목질바이오매스의 당화특성을 분석하기 위하여 분해공정 동안 압력을 23MPa(물의 임계압력)로 고정하고 물의 아임계 온도$(325^{\circ}C,\;350^{\circ}C)$와 초임계 온도$(380^{\circ}C,\;400^{\circ}C,\;425^{\circ}C)$에서 현사시나무 목분을 각각 60초 동안 처리하였다. 생성된 현사시나무의 분해산물에는 액상과 고형분의 분해산물이 섞여 있었다. 각 처리조건에 따른 목질바이오매스의 분해율은 온도가 상승함에 따라 증가하였으며 초임계 온도인 $425^{\circ}C$에서 최고 83.1%의 분해율을 나타냈다. 아임계 및 초임계수에 의해서 생성된 단당류는 고성능 음이온 교환 크로바토그래프(HPAEC)를 이용하여 분석하였다. 목질바이오매스의 초임계수 분해과정에서 처리 온도가 높아지면서 단당류 수율은 증가하는 경향을 보였으며, $425^{\circ}C$에서 가장 높은 7.3%의 단당류 수율을 나타내었다. 아임계 온도 범위에서는 현사시나무의 섬유소 성분 중에서 자일란이 우선적으로 분해되어 자일로스의 생성비율이 비교적 높았으며, 처리온도가 높아지면서 셀롤로오스의 분해에 의한 글루코오스 생성율이 급격히 상승하였다. 이렇게 생성된 단당류 성분들은 고온의 반응조건하에서 열분해 반응에 의해서 더욱 분해되어 퓨란계 화합물로 변형되었다.

• Journal of the Korean Chemical Society
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• v.44 no.1
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• pp.24-29
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• 2000

Yoqurt products are known to be effective for enhancing health and preventing diseases such as cancers. Such effects are generally believed to be due to actions of polysacchmides in yoqurt products. In this study we have determined compositions of monosaccharides in hydrolysates of commercial yoqrtrt products as the first step of understanding structures of polysaccharides. The yoqtrrt products were ttltracentrifuged, filtered, hydrolyzed in 1M sulfuric acid and neutralized. A portion of the solution was taken and evaporated to dryness, denvatized with TMSI (trimethly- silylimidazole) and analyzed by GC/MS. We found that the monosaccharides were fructose, glucose, and galactose. Their compositions were variant among several yoqtrrt products.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.533-538
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• 1989

The enhanced growth and lactic fermentation of L. acidophilus, when mixed with S. uvarum, was investigated. Spent medium of S. uvarum, at 10%, stimulated the growth and lactic fermentation of L. acidophilus, and also increased the content of monosaccharide while decreased the contents of sucrose, raffinose, and stachyose in soymilk. While single culture of L. acidophilus consumed only the monosaccharides in soymilk, the mixed culture of L. acidophilus and S. uvarum consumed almost all the oligosaccharides as well as the monosaccharides in soymilk. Thus it was assumed that S. uvarum converted the oligosaccharides into monosaccharides so that L. acidophilus can produce more lactic acid and cell mass by using the increased monosaccharides.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.191-196
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• 1989

Monosaccharide content of four forest soils were analyzed. Two soils under coniferous forest trees and another two under duciduous forest trees of Mts. Zeombong and Odae in Kangweon-Do were sampled from the surface horizon down into the subhorizons. 1. The largest amount of monosaccharide is found in the surface organic horizon of each soil and with increasing depth the amount decreases as might be expected considering total organic matter content. 2. Hexoses (galactose, glucose, mannose) predominate over pentoses (arabinose, ribose, xylose) and deoxyhexoses (fucose, rhamnose), the latter being in the smallest amount. Glucose is the most abundant monosaccharide in all samples regardless of vegetation of soil or depth. In general the content of each monosaccharide follows the order of glucose > manrtose > galactose > arabinose > xylose > rhamnose > fucose > ribose. 3. Very little amount of ribose is present even in organic horizons of coniferous forest soils. In samples taken from deciduous forest soils ribose is virtually absent. 4. The relative proportion of monosacchaiide to the total soil organic matter decreases with increasing depth, which may be resulted from the effect of prolonged humification. The total monosaccharide in the organic surface layer amounts to 27-50% of the total organic carbon or 15.7-29% of the total organic matter. Hexoses alone take the largest share of 20-38% of the carbon, or 12-22% of the organic matter.

• The Korean Journal of Food And Nutrition
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• v.13 no.3
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• pp.226-234
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• 2000

본 연구에서는 밤차로부터 용출한 차액의 단당류, 아미노산 및 카페인을 시판중인 현미녹차와 결명자차의 차액과 비교분석함을써 밤차의 기능성 건강음료로 활용하기 위한 기초자료를 규명하였으며 그 결과는 다음과 같다. 1. 현미녹차의 차액에는glucose와 galactose약 20:1 정도의 비율로 검출되었으며 용출시간이나 용출온도에 따른 당류의 변화는 적다. 2. 밤차의 차액에는 glucose, galactose, mannose등이 약 100:1:10의 비율로 존재하여 용출시간이나 용출온도에 의한 변화는 적다. 특히 mannoxe는 천연에서 유리상태로존재하기 어려운 희귀한 유리당이다. 3. 결명자차 차액에서는 당류를 확인할 수 없을 정도로 낮은 농도를 나타냈으며 결명자차의 amino산 함량은 현미녹착나 밤속껍질차의 아미노산 함량에 의해 1.6~1/7에 지나지 않았다.4. 현미녹차의 차액 중 아미노산은 glutamic acid, aspartic acid, serine, methionine, alanine 등의 순서로 검출되었으며, 용출온도와 용출시간에 비례하여 농도가 증가하였고, 아미노산의 용출은 대부분 첫회에 이루어지고 있다는 것을 알 수 있었다. 5. 밤차의 차액 중에 아미노산은 alanine, asparagine, aspartic acid, proline, valine 등의 순으로 많이 함유되어 있고, alanine, asparagine, proline등은 현미녹차에 비하여 함유량이 많으며 glutamic acid, serine, methionine, glutamine 등은 상대적으로 소량 함유되어 있었다. 용출온도와 용출시간에 비례하여 농도가 증가하는 경향을 나타냈으며 아미노산의 요출은 대부분 첫회에 이루어지고 있다는 것을 알수 있었다. 6. 현미녹차는 카페인을 126~162 mg/L 정도로 다량 함유하고 있으나 밤차나 결명자차는 함유하지 않았다.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.586-591
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• 1992

The oligosaccharide metabolism in soymilk was investigated by mixed culture with Lactobacillus acidophilus and Saccharomyces uvarum. When Saccharomyces uvarum was cultured in soywhey, change of oligosaccharide could be shown apparently. However, Lactobacillus acidophilus could not utilize oligosaccharide in soywhey for growth and lactic acid production. During the fermentation of mixed culture with Lactobacillus acidophilus and Saccharomyces uvarum, Saccaharomyces uvarum was supposed to convert oligosaccharide to monosaccharide first and then Lactobacillus acidophilus to convert these produced monosaccharide to lactic acid.

• Journal of Nutrition and Health
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• v.54 no.4
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• pp.355-372
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• 2021

Purpose: This study aimed to provide baseline data for establishing a sugar reduction policy at coffee shops by analyzing the factors that affect a coffee shop user's perception and behavioral intention of reducing sugar intake. Methods: An online survey was conducted involving 1,274 Daegu citizens aged 19-49 years, who had visited coffee shops within the last month. Results: When visiting a coffee shop, the purchase of sweet drinks was higher in the younger age group, and the addition of syrup or sugar was higher in the older age group. Of the total respondents, 42.1% were aware that some coffee shops accommodate reduced sugar requests, 57.9% perceived the need to reduce sugar in coffee shop beverages and 22.3% had purchased beverages intending to reduce their sugar intake. In addition, 59.7% knew about sugar nutrition labeling, and 68.8% perceived the need for nutrition labeling for sugar. When purchasing beverages, 35.6% checked the nutrition labeling, and 77.2% purchased alternative drinks when the sugar content was high. Guiding the choice of sweetness levels in coffee shop orders was seen to have the highest effectiveness and intention to reduce sugar intake. Moreover, the perceived need to reduce sugar intake had the most positive effect on the behavioral intention to reduce sugars in coffee shop beverages (β = 0.558, p < 0.001). Conclusion: Although the overall awareness and practice of reducing the sugar intake in coffee shop users were low, the behavioral intention to reduce sugars was positive, and this was most affected by the perception of the need to reduce sugars. Therefore, there is a need for differentiated education and promotion for each age group for recognizing the necessity and outlining methods for reducing sugar intake. Furthermore, coffee shops should reflect customer's sugar reduction needs.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.1
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• pp.21-25
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• 1990

The amounts of monosaccharides in acid hydrolysates of decomposing plant residues under laboratory conditions were determined. Straw of cereal rice and barley, wild grass cutting, and litters of deciduous and coniferous forest trees were treated to decompose for 90 days. Samples for the analysis of mono-saccharides were taken at 3 different periods of incubation. 1. Fractions of monosaccahrides in plant residues steadily decreased with the time of decomposition. In some samples there appeared an intermediate stages where the fractions reached the highest level. 2. Decomposition of barley straw occured at a faster rate than that of rice straw, and so did the decomposition of deciduous litter than that of coniferous litter. 3. Cereal crop residues of rice and barley were richer in monosaccharides than residues of wild grass cutting and forest litters. 4. Distiction between monosaccharides of plant origin and those of microbial origin was not possible to make in this study. 5. Glucose was the predominent monosaccharide and fucose was the monosaccharide contained in the smallest amount. No measurable ribose was detected from any sample. 6. The relative proportion of galactose in creased with the time of incubation. 7. In general, the proportion of fucose decreased with time and so did that of rhamnose, rhamnose of rice straw residue being the exception. 8. The orders of abundance of monosaccharides after decomposition of 90 days were as the following: in rice straw; glucose > xylose > arabinose > galactose > rhamnose > mannose > fucose, in barley straw; glucose > xylose > arabinose > galactose> mannose > rhamnose > fucose, in wild grass cutting; glucose > xylose > galactose arabinose> rhamnose mannose > fucose, in deciduous litter; glucose > arabinose > xylose galactose > mannose > rhamnose = fucose, and in coniferous litter; glucose > xylose > galactose > arabinose mannose > rhamnose > fucose.

• Korean Journal of Microbiology
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• v.47 no.4
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• pp.281-288
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• 2011

To screen downstream genes of Aspergillus nidulans MsnA showing amino acid sequence similarity to the zinc finger region of Msn2/4 stress response transcription factors in Saccharomyces cerevisiae, differentially expressed genes (DEG) in MsnA overexpressed or msnA null mutant strains compared to wild type have been isolated. The cognate gene IDs were identified by DNA sequencing of the selected DEGs. Among those, DEG6 was known as mstB encoding a putative monosaccharide transporter. Expression level of mstB mRNA was increased in MsnA overproducing strains and MsnA bound directly to the promoter region of mstB in vitro. MstB containing twelve transmembrane domains exhibited 80% of amino acid sequence identities to A. niger MstA a high-affinity monosaccharide transporter. A null mutant of mstB was phenotypically undistinguishable to wild type. On the other hand, forced overexpression of MstB caused the increased formation of sexual structure cleistothecia in 0.1% glucose condition where wild type showed almost no cleistothecia. This result implies that mstB is involved in transport of monosaccharide required for sexual differentiation.

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.157-161
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• 1994

The pigments of acetylshikonin and isobutylshikonin isolated from the roots of Lithospermum erythrorhizon were determined over a period of storage for their stabilities influenced by mono- and disaccharides and acids. In general. sugars and acids caused an increase in stability of acetylshikonin at the various concentrations. These studies indicated that acetylshikonin and isobutylshikonin can be used in foods as the natural colorant under selected conditions.