• Culinary science and hospitality research
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• 제12권4호
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• pp.299-319
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• 2006

The purpose of this study was to investigate the changes of hardness and microstructure of Dongchimi cooked with various sources of sugar(xylitol, xylose, sugar, pear juice). It was fermented at $10^{\circ}C$ for 60 days. The changes of pH in Dongchimi used different kinds of sugar decreased in all samples during the fermentation period, and then showed a slow decrease after 12 days of fermentation. The total acidity of Dongchimi using xylitol arrived slowly at the best tasting condition($0.3\sim0.4$ point) compared with other conditions. The changes of salt content were showed high as compared with other test conditions in 0 day, the day of fermentation. At the early stage of fermentation, the changes of turbidity of Dongchimi using sugar, pear juice were showed high as compared with those of Dongchimi using xylitol, xylose for $5\sim15$ days of fermentation. The maximum cutting force of Chinese radish Dongchimi showed the highest value among al at the 25 th day of ripening and then decreased gradually. The maximum cutting force of Dongchimi using sugar showed the lowest. The calcium and magnesium contents of Dongchimi juice and Chinese radish Dongchimi juice using xylitol were observed high at the early stage of fermentation and showed the highest value during the fermentation period. The microstructure showed disintegration appearance of middle lamella and cell wall during the fermentation period.

• Mycobiology
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• 제44권1호
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• pp.48-53
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• 2016

Lenzites betulinus, known as gilled polypore belongs to Basidiomycota was isolated from fruiting body on broadleaf dead trees. It was found that the mycelia of white rot fungus Lenzites betulinus IUM 5468 produced ethanol from various sugars, including glucose, mannose, galactose, and cellobiose with a yield of 0.38, 0.26, 0.07, and 0.26 g of ethanol per gram of sugar consumed, respectively. This fungus relatively exhibited a good ethanol production from xylose at 0.26 g of ethanol per gram of sugar consumed. However, the ethanol conversion rate of arabinose was relatively low (at 0.07 g of ethanol per gram sugar). L. betulinus was capable of producing ethanol directly from rice straw and corn stalks at 0.22 g and 0.16 g of ethanol per gram of substrates, respectively, when this fungus was cultured in a basal medium containing 20 g/L rice straw or corn stalks. These results indicate that L. betulinus can produce ethanol efficiently from glucose, mannose, and cellobiose and produce ethanol very poorly from galactose and arabinose. Therefore, it is suggested that this fungus can ferment ethanol from various sugars and hydrolyze cellulosic materials to sugars and convert them to ethanol simultaneously.

• Journal of Microbiology
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• 제39권1호
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• pp.24-30
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• 2001

In addition to effecting the catalysis of sugar uptake, the bacterial phosphoenolpyruvate::sugar phosphotransferase system regulates a variety of physiological processes. In a previous paper [Seok et al.,(1997) J. Biol. Chem. 272, 26511-26521], we reported the interaction with and allosteric regulation of Esiherichia coli glycogen phosphorylase activity by the histidine-containing phosphocarrier protein HPr in vitro. Here, we show that the specific interaction between HPr and glycogen phosphorylase occurs in vivo. To address the physiological role of the HPr-glycogen phosphorylase complex, intracellular glycogen levels were measured in E. coli strains transformed with various plasmids. While glycogen accumulated during the transition between exponential and stationary growth phases in wildtype cells, it did not accumulate in cells overproducing HPr or its inactive mutant regardless of the growth stage. From these results, we conclude that HPr mediates crosstalk between sugar uptake through the phosphoenolpyruvate:sugar phosphotransferase system and glycogen breakdown. The evolutionary significance of the HPr-glycogen phosphorylase complex is suggested.

• The Korean Journal of Food And Nutrition
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• 제21권4호
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• pp.391-396
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• 2008

In this study, we attempted to optimize the fermentation processes in the production of lactic acid juice with 20% Maesil(Prunus mume) extract using Lactobacillus plantarum isolated from Kimchi, assessing a variety of pH, temperature, sugar compositions, and sugar concentrations. In the preparation of fermented Maesil(Prunus mume) extract, the optimal pH and fermentation temperature were 4.0 and $35^{\circ}C$, respectively. When the effects of various sugar sources and concentrations on lactic acid fermentation were assessed, 15% fructose was shown to yield more acid productivity than was observed with other sugar sources. The optimum composition, on the basis of our sensory evaluations, was determined to be a fructose concentration of 15% and a fermentation time of $72{\sim}96$ hours.

• Korean journal of food and cookery science
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• 제9권2호
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• pp.78-81
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• 1993

"Yut Kang Jung" is a kind of Korean traditional cookie. The purpose of this study is to examine the effects of various kinds of syrups and cooking methods of Yut Kang Jung. The quality of Yut Kang Jung was evaluated by sensory and Instron machine test. The results is as follows; 1. The Recipe of the best Yut Kang Jung is this: White sesame 120g, sugar syrup 40g, and crude maltose watery 50g are used. Mixing sugar syrup crude maltose watery boiling for 4 min, in temperature $105^{\circ}C$. The sugar density after boiling was 86%. 2. Yut Kang Jung made by sugar syrup and crude watery maltose got the best result in sensory best. 3. Yut Kang Jung made by crude watery maltose got the best result in mechanical test. 4. The comparison between the sensory test & mechanical test were as follow; The hardness in the mechanical test was comparable with hardness & fracturability in the sensory test, and the chewiness in the mechanical test was comparable with flavor, adhesiveness, fractur ability in sensory test.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1526-1526
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• 2001

To improve the accuracy of sweetness sensor in automated sorting operations, it is necessary to clarify unevenness of the sugar content distribution within fruits. And it is expected that the technique to evaluate the content distribution in fruits contribute to the development of the near-infrared (NIR) imaging spectroscopy. Sugiyama (1999) had succeeded to visualize the distribution of the sugar content on the surface of a half-cut green fresh melon. However, this method cannot be applied to red flesh melons because it depends on information of the absorption band of chlorophyll (676 nm), which is affected by the color of the fresh. The objective of this study was to develop the universal visualization method depends on the absorption band of sugar, which can be applied to various kinds of melons and other fruits. The relationship between the sugar contents and absorption spectra of both green and red fresh melons were investigated by using a NIR spectrometer to determine the absorption band of sugar. The combination of 2$\^$nd/ derivative absorbances at 902 nm and 874 nm was highly correlated with the sugar contents. The wavelength of 902 nm is attributed to the absorption band of sugar. A cooled charge-coupled device (CCD) imaging camera which has 16 bit (65536 steps) A/D resolution was equipped with rotating band-pass filter wheel and used to capture the spectral absorption images of the flesh of a vertically half-cut red fresh melon. The advantage of the high A/D resolution in this research is that each pixel of the CCD is expected to function as a detector of the NIR spectrometer for quantitative analysis. Images at 846 nm, 874 nm, 902 nm and 930 nm were acquired using this CCD camera. Then the 2$\^$nd/ derivative absorbances at 902 nm and 874 nm at each pixel were calculated using these four images. On the other hand, parts of the same melon were extracted for capturing the images and squeezed for the measurement of sugar content. Then the calibration curve between the combination of 2$\^$nd/ derivative absorbances at 902 nm and 874 nm and sugar content was developed. The calibration method based on NIR spectroscopy techniques was applied to each pixel of the images to convert the 2$\^$nd/ derivative absorbances into the Brix sugar content. Mapping the sugar content value of each pixel with linear color scale, the distribution of the sugar content was visualized. As a result of the visualization, it was quantitatively confirmed that the Brix sugar contents are low at the near of the skin and become higher towards the seeds. This result suggests that the visualization technique by the NIR imaging spectroscopy could become a new useful method fer quality evaluation of melons.

• Journal of Life Science
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• 제14권1호
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• pp.98-103
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• 2004

Various bacterial strains were isolated from water in a paddy field, and their seaweed degrading activities were investigated. As the result, 16 strains were obtained from the microflora sample. They were incubated in a liquid medium of sea tangle powder for 3 weeks. Ratios of reduced sugar to total sugar of the liquid medium were measured once a week during the incubation period. Ratio of reduced sugar to total sugar of 30A412 strain was highest. Accordingly, 30A412 strain was incubated in three different liquid media of sodium alginate, sea tangle powder, and sea mustard powder for 3 or 4 weeks. The ratios of reduced sugar to total sugar and cell growth were measured once a week during the incubation period. Ratios of reduced sugar to total sugar and cell growth were increased with the incubation period. Cell growth and degrading ratio were highest in the liquid medium with sea mustard powder.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제36권6호
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• pp.563-567
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• 2003

Various bacterial strains were isolated from rice field ditch water, and their seaweed degrading activities were investigated. They were incubated in a liquid medium of sea tangle (Laminaria iaponica) and sea mustard (Undaria pinnatifida) powder for 3 weeks. Ratios of reduced sugar to total sugar of the liquid medium were measured once a week. Ratios of reduced sugar to total sugar of 27A311, 27C221 27A111 and 27B121 strains were highest. Accordingly, these four strains were incubated in 3 different liquid media of sodium alginate, sea tangle powder, and sea mustard powder for 3 or 4 weeks. The ratios of reduced sugar to total sugar and cell growth were measured once a week. Cell growth was higher in 27A111 and 27C221. Ratios of reduced sugar to total sugar was higher for 27C221 in the liquid mediums with sodium alginate and sea mustard powder, and for 27A111 in the liquid medium with sea tangle powder.

• Korean journal of food and cookery science
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• 제13권3호
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• pp.356-363
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• 1997

Soybean Da-sik was prepared with various soybean powder processing methods (roasting, steaming, and steaming followed by roasting) and sugar types (honey, oligo-sugar), and their sensory and physical characteristics were evaluated to determine the optimum preparation method. The results were as follows: 1. For Sample 1 (roasting soybeans for 30 min at 150$^{\circ}C$ and grinding), the best appearance of Da-sik was obtained when the content of honey was adjusted to 35 g, and the color with 30 g of oligo-sugar by sensory evaluation. The optimum texture was obtained with 40 g of honey, and the optimum chewiness with 30 g of honey Overall, the optimum quality was obtained with 35 g of honey, and oligo-sugar seemed to have less influence on the quality. In case of Sample 2 (four rounds of steaming and drying for 35 min), 40 g of oligo-sugar was found to exhibit the best quality, and honey was less effective. For Sample 3 (three rounds of drying followed by 15 min roasting at 150$^{\circ}C$), the best appearance and color were obtained with 35 g and 40 g of honey, respectively. The texture was most favorable with 40 g of honey, while the chewiness was best with 30 g of honey, suggesting 35 g of honey was the optimum level for Sample 3 soybean powder than oligo-sugar. 2. The springiness, gumminess, hardness and chewiness measured by a texture analyser were highest with Sample 1 containing 30 g of honey, and the cohesiveness with 40 g of honey. 3. For color, the best brightness and yellowness were obtained with Sample 1 with 30 g of honey. The redness was highest with Sample 3 with 40 g of honey. Overall, the desirable recipe for soybean Da-sik was 35 g of honey for Sample 1 and Sample 3, and 40 g of oligo-sugar for Sample 2.

• Proceedings of the Plant Resources Society of Korea Conference
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• 한국자원식물학회 2023년도 임시총회 및 춘계학술대회
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• pp.63-63
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• 2023

Sugar beet (Beta vulgaris L.) is one of the most important sugar crops and provides up to 30% of the world's sugar production. In this study, we mainly performed RNA-sequencing to obtain identify putative genes involved in biosynthesis pathway of sucrose in sugar beet and comparative transcriptomic analyses in the four developmental stages (50, 90, 160 and 330 days after seedling). As a result of the sugar content analysis, it was increased significantly from 50 to 160 days after seedling (DAS), and then decreased at 330 DAS. On the other hand, the taproot weight, length, and width were increased during all the growth periods. Out of 21,451 genes with expressed value, 21,402 (99.77%) genes had functional descriptions. Among the three comparisons, S1 (50 DAS) vs. S2 (90 DAS), S1 vs. S3 (160 DAS), and S1 vs. S4 (330 DAS), expression profiling of the transcripts was identified 4,991 with differentially expressed genes (DEGs). By comparing the top 20 enriched gene ontology (GO) terms as three comparisons, the top GO terms were commonly confirmed with external encapsulating structure, cell wall, and extracellular regions. In addition, the 38 enriched candidate genes related to sucrose biosynthetic pathway were screened from the entire DEG pool, and the candidate genes might be providing a basic data for further sugar metabolism studies in development of sugar beet taproot.