• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.751-756
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• 1999

For mass production of poly(3-hydroxybutyrate) (PHB), high cell density cultures of Ralstonia eutropha were carried out in 2.5-1 and 60-1 fermentors by two fed-batch culture techniques of nitrogen and phosphate limitation. When the nitrogen limitation technique was employed using both an on-line glucose monitoring and control system, a high concentration level of PHB (121g/l) was obtained in the small-scale fermentor of 2.5 1. However, the PHB concentration obtained in a large-scale fermentor of 60 1 only turned out to be 60g/l. In contrast, when another fed-batch culture technique of the phosphate-limitation employing dissolved oxygen (DO) stat glucose feeding was used, a large amount of PHB was successfully produced in both 60-1 and 2.5-1 fermentors. In a 2.5-1 fermentor, concentrations of PHB and cells obtained in 58 h were 175 and 210 g/l, respectively, which corresponded to the PHB productivity level of 3.02 g/l/h. In a 60-1 fermentor, a final cell concentration of 221 g/l and a PHB concentration of 180 g/l with PHB productivity level of 3.75 g/l/h were obtained in 48h. PHB content and yield from glucose were 81% and 0.38g PHB/g glucose, respectively. These data suggest that the phosphate limitation technique is more effective compared to nitrogen limitation in the mass production of PHB by R. eutropha of a large scale.

• Food Science and Preservation
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• v.14 no.5
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• pp.552-556
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• 2007

The effects of alcohol concentration (30% 45% and 60%) on quality changes of maesil (Prunus mume) liqueur during leaching and ripening for 5 months were examined. Total acidity, pH and color of the liqueur generally increased with an increase alcohol concentration for 2 months. Thereafter the significant change did not occur. The contents of reducing sugar and polyphenol in the liqueur increased with an increase alcohol concentration and ripening periods. The major components of free sugar in maesil liqueur were fructose, glucose, sucrose and maltose. The content of fructose and glucose were higher than those of sucrose and maltose regardless alcohol concentration. Sucrose and maltose did not detect in the liqueur after leaching and ripening for 2 months. The major components of organic acid in maesil liqueur were citric, lactic, malic, and acetic acids. The optimal alcohol concentration was 45% and the duration of leaching and ripening was about 2 months for production of high-proof maesil liqueur.

• Journal of Sensor Science and Technology
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• v.23 no.5
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• pp.295-298
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• 2014

A novel approach to fabricating high-performance glucose sensors is reported, which is based on the process of self-assembled monolayers (SAMs). In this study, we have particularly used ${\alpha}$-lipoic acid (LA) SAMs for the glucose sensors. To our best knowledge, this study is the first one to use LA as SAMs for this purpose. N-hydroxysuccinimide (NHS) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) were deliberately attached at the same time on the LA SAM. Then, glucose oxidase ($GO_X$) and horseradish peroxidase (HRP) were sequentially immobilized. Thus, the HRP/$GO_X$/NHS-EDC/LA-SAM/Au/Cr/glass working electrode was developed. The glucose-sensing capability of the fabricated sensor was systematically measured by the use of cyclic voltammetry in the range of 1-30 mM glucose in phosphate-buffered saline. The result showed a good sensitivity, that is, as high as $27.5{\mu}A/(mM{\cdot}cm^2)$. This result conspicuously demonstrates that LA can be one of promising substances for use as SAMs for accurately monitoring trace levels of glucose concentration in human blood.

• Asian Journal of Turfgrass Science
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• v.11 no.1
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• pp.59-72
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• 1997

The influence of respiration on photosythetic electron transport were investigated in the Wid type and psaB mutants from Syneehocystis sp. PCC6803. The amount of glucose uptake in the wild type was proportional to the glucose concentration added in wild type and less than that of psaB mutants in the dark. It was suggested that psaB mutants more depend on the glucose than the wild type. It was investigated how the activities of isocitrate dehydrogenase(IDH) and glucose-6-phos-phate dehydrogenase(G6PDH) were changed. The activities of IDH were very low. While, the ac-tivities of G6PDH were much higher than that of IDH. These results agree to the reports that ex-ogenous glucose was dismilated aerobically via Oxidative Pentose Phosphate Pathway in heterotrophic cyanobacteria. PsaB mutants showed high G6PDH activity in the presence of glucose as well as in the dark and high respiratory activities especially in the dark. It was also investigated how photosynthetic electron transport activities were changed. PsaB mutants showed higher photosynthetic electron tranasport activities than wild type in the presence of glucose as well as in the dark. In the results, it was proposed that photosynthetic electron transport between PS I and PS U was complemented by respiratory electron transport through the NADPH generated by Dxidative Pentose Phophate Pathway in psaB mutant from Synechocystis sp. PCC6803. Key words: Photosynthetic electron transport, Respiration, Synechoystis sp. PCC6803, psaB mutant, Glucose uptake, IDH, G6PDH, Respiratory electron transport activity.

• Journal of Nutrition and Health
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• v.37 no.2
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• pp.75-80
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• 2004

This study was carried out to investigate the supplementary effects of Suwon 464, which has over two times of dietary fiber content compared with normal rice (Ilpum), on blood glucose in diabetic mice. We supplied 5 kinds of experimental diets (corn starch diet as a control (CO), Ilpum polished rice diet (IP), Ilpum brown rice diet (IB), polished rice diet (SP) and brown rice diet (SB) of Suwon 464) to diabetic mice for 8 weeks, after analyzing dietary fiber contents of 5 experimental diets. Diet intake, body weight and contents of blood glucose, hemoglobin $A_{lc}$ and insulin were measured. The dietary fiber contents in CO, IP, IB, SP, and SB diets were 1.0, 1.2, l.4, l.4, and 2.0% respectively. Body weight was lower in SB group than the other groups though there was no significant difference in diet intake among experimental groups. The concentration of blood glucose in diabetic mice was lower in SB group than the other groups during the supplementary period of experimental diets. The hemoglobin Ale and serum insulin levels were lower in SP and SB groups. These results suggested that the brown rice of Suwon 464 with high dietary fiber can control diabetes in diabetic mice by reducing the blood glucose and hemoglobin Ale. (Korean J Nutrition 37(2): 75-80, 2004)

• Korean Journal of Acupuncture
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• v.23 no.1
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• pp.59-66
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• 2006

Objective : To investigate the effects of Yullmoo (Coix lachryma-jobi var. mayuen stapf.) Pharmacopuncture on plasma lipid composition and glucose concentration in hyperlipidemic rats. Methods : ${\beta}-lipoprotein$ free fatty acids, triglyceride and total cholesterol levels in Yullmoo (Coix lachryma-jobi var. mayuen stapf.) Pharmacopuncture groups were compared with those in the control group. Results : Concentration of ${\beta}-lipoprotein$ showed no significantly different in all treatment groups. Concentration of free fatty acids, triglyceride and total cholesterol in plasma were decreased in the Yullmoo (Coix lachryma-jobi var. mayuen stapf.) Pharmacopuncture groups. In the Yullmoo (Coix lachryma-jobi val. mayuen stapf.) Pharmacopuncture groups, plasma LDL-cholesterol showed a lower value and HDL-cholesterol showed a higher value than those of the control group. Contents of glucose were decreased in the Yullmoo (Coix lachryma-jobi val. mayuen stapf.) Pharmacopuncture groups. Conclusions : The results suggest that Yullmoo (Coix lach.yma-jobi var. mayuen stapf.) Pharmacopuncture may have an impact on lipid metabolism to potentially prevent obesity and enhance treatment effect.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.91-94
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• 2002

Arachidonic acid is a polyunsaturated fatty acid(PUFA) containing twenty carbon atoms with four double bonds. The family of w-6 PUFA, including arachidonic acid as well as r-linoleic acid, was served as intermediates in the formation of several key prostaglandin and leukotrienes. Several fungal strains of the genus Mortierella accumulate high amounts of arachidonic acid. In this study experiments were carried out to optimize the culture conditions for the mass production of fungus Mortierella alpina DSA -12 and lipid production with high proportion of polyunsaturated fatty acids, especially arachidonic acid. The batch culture was carried out in 500 L fermenter containing 50 g/L glucose, 18 g/L corn-steep powder and 100 mg/L MnS04 under $25^{\circ}C$, aeration rate of 0.5 vvm and agitation speed of 200 rpm without pH control. As a result, we could be obtained 22 g/L of cell mass with high contents of lipid 12.1 g/L) and arachidonic acid (5.1 g/L) The intermittent fed-batch culture was performed in the medium containing 20 g/L glucose and 10 g/L corn-steep powder. The final glucose concentration was 170 g/L and pH was maintained at 5.5 ${\sim}$ 6.0 by adding 14% ammonia solution. It was shown relatively high cell concentration (70.5 g/L) with high contents of lipid (45.8 g/L) and arachidonic acid 08.3 g/L). Therefore, when compared to batch cultures, the high concentration of arachidonic acid could be obtained by fed-batch culture using M. alpina DSA -12. These results imply that the fed-batch culture of M. alpina DSA -12 was feasible in industrial purpose and could be employed in the commercial production of arachidonic acid.

• Journal of Electrochemical Science and Technology
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• v.15 no.1
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• pp.32-50
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• 2024

Diabetes mellitus is one of the common chronic diseases, seriously threating to human health. The continuous monitoring of blood glucose concentration can effectively prevent diabetic diseases. The sensing performance of glucose non-enzymatic sensors is mainly determined by working electrode materials. Metal-organic frameworks (MOFs) are recognized as promising candidate for glucose sensor application, due to its large surface areas, ordered porous structure and nearly infinite designability. In this review, the sensing performance, research progress and future challenge of non-enzymatic glucose sensors based on MOF-based materials in recent years are presented. We hope that this review would provide valuable technology guidance for high performance non-enzymatic glucose sensors based on MOFs.

• Journal of Environmental Science International
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• v.30 no.7
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• pp.537-545
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• 2021

This study aimed to investigate the improvement effect of 5% (w/w) mung bean (Phaseolus aureus L.) on lipid composition and protein concentration in hyperlipidemic rats. Seven-week-old male (Sprague-Dawley) rats were divided into four groups (n=6, each), and fed experimental diets containing mung bean meal [basal diet+5% (w/w) mung bean (BM), basal-hyperlipidemic diet+5% (w/w) mung bean (BHM)], basal-hyperlipidemic diet (BH), and control (basal diet, BD). Lipid composition in the mung bean diet groups (BM and BHM) evidenced significant reductions in serum total cholesterol, low-density lipoprotein cholesterol, atherosclerotic index, cardiac risk factor, triglyceride, phospholipid, free cholesterol, cholesteryl ester, blood glucose, nonesterified fatty acid, and an elevation in high-density lipoprotein cholesterol. The serum albumin/globulin ratio was increased in mung bean diet-supplemented rats compared to that in hyperlipidemic rats (p < 0.05). Total calcium, phosphorus and potassium concentrations in sera were higher in the BM, BHM and BD groups than in the BH group. Concentrations of sodium and chlorine in sera were lower in the mung bean diet-supplemented groups than in the hyperlipidemic group. The in vivo experiments showed that ingestion of mung bean was effective in improving lipid composition, protein concentration, and blood glucose.

• The Journal of the Korean Society for Microbiology
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• v.20 no.1
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• pp.55-63
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• 1985

Phosphate, ammonia, glucosamine, glucose, pyruvate, succinate, fumarate, malate and acetate were examined for their ability to control the heat-stable enterotoxin (ST) production in succinate salts medium or in M9 medium. The results obtained were summerized as follows. 1. When the initial phosphate concentration was adjusted to 1.0mM, ST production was decreased to 80u/ml or less. But when the initial phosphate concentration was adjusted to 64mM or 100mM, enterotoxin production was 320u/ml. 2. When the initial ammonia concentration in the medium was adjusted to 1.0mM, no ST production and cell growth were observed. But when ammonia concentration was adjusted to 10mM, 19mM, 38mM or 76mM, enterotoxin production was 320u/ml. 3. Among carbon sources, glucosamine, glucose, pyruvate, succinate, fumarate, malate and acetate, acetate supported the highest specific production (928 unit/O.D.) of heat-stable enterotoxin. From this results, we could assume that heat-stable enterotoxin production is controlled by stringent control mechanism. 4. When the pH of the succinate salts medium was kept between 6.2 to 6.5, no heat-stable enterotoxin production was observed, but when the pH of the medium was kept between pH 6.2 to 6.5, 267 unit/O.D. of heat-stable enterotoxin was produced. 5. Glucose inhibited the heat-stable enterotoxin production and the mechanism was assumed due to its capacity to lower the pH of the medium during catabolysis and its high metabolic energy.