• IEMEK Journal of Embedded Systems and Applications
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• v.15 no.4
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• pp.167-175
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• 2020

A blood-glucose meter is one of the in vitro diagnostic devices to measure and control the glucose concentration of diabetics. In order to measure the glucose level in the blood, the common method is to measure the amount of electrons, that is, the output current generated by glucose oxidation after a blood sample is inserted into the test strip containing an enzyme. The hematocrit is an obstacle in measuring accurate blood glucose concentration. This paper deals with the design and implementation of a blood-glucose meter to correct the hematocrit interference. We propose a sequential method which measures impedance using the alternating current and then measures glucose in the blood using the direct current. In addition, this paper introduces how to use commercial glucose strips based on the proposed system. Finally, we conducted the performance evaluation of the proposed system by comparing the measured current and impedance with those of the references. As a result, the standard deviation of the current measurement is approximately 0.6nA and the impedance measurement error for measuring the hematocrit is approximately within 1%. The proposed system will improve the accuracy of the conventional blood-glucose meter by reducing the hematocrit interference.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.268-272
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• 2003

Experiments were carried out to investigate the selection of industrial medium and optimization of fermentation process for the production of erythritol by Candida magnoliae SR101. In the batch fermentation, light steep water(LSW) was the best nitrogen source for the industrial production of erythritol. For the optimization of culture condition, the batch culture was performed. When the concentration of LSW was 65 mL/L in the defined medium containing 250 g/L of glucose, 44% of erythritol yield with 110 g/L of erythritol concentration and 0.66 g/L-hr of productivity, respectively were obtained. Two-stage fed-batch culture was performed to improve the volumetric productivity of erythritol. High density cell culture in the growth stage was performed by batch type with 100 g/L glucose and 500 mL/L LSW concentration, respectively. The cell yield was 0.72 g-cell/g-glucose. Productivity of erythritol was increased and concentration of organic acids such as gluconic acid and acetic acid were decreased when initial pH of 6.5 controlled by 28% ammonia water For increasing yield of erythritol, glucose concentration in the production stage was tested. 37% of total erythritol yield with 186 g/L of erythritol concentration and 1.66 g/L-hr of erythritol productivity were obtained when 820 g of glucose powder was directly added for making up 450 g/L of glucose at production stage.

• KSBB Journal
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• v.15 no.2
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• pp.139-144
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• 2000

Automatic addition of glucose and ammonium to an alcohol distille깨 wastewater and the control of them at low $\infty$ncentration were tried to efficiently increase the cell concentration of a baker's yeast c비tivated in that wastewater. Added g glucose was indirectly controlled to less than 116 mg/L by a method which used DO as control parameter. Ammonium was a automatically measured and controlled within the range of 7.0~27.7 mM by a homemade on-line system which adopted FIA a as measurement method. Maximum specific growth rate and biomass yield to glucose were $0.21 hr^{-1}$ and about 0.78 g/g, w which were significantly increased values in contrast to those of an experiment without ammonium control. Biomass yield to a ammonium was 11.3 gIg. Cell cone엉ntration could be increased from 2.6 g/L to 18.5 g/L by the add ion of glucose and a ammonium.

• KSBB Journal
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• v.9 no.3
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• pp.339-345
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• 1994

Deletions between UASG and the GALI TATA box reduced glucose repression and allowed constitutive expression of the gene product in the absence of galactose. The relative inducer level (ratio of galactose/glucose concentrations) affected the extent of gene expression and glucose repression. Glucose repression was reduced by a factor of 2 to 5 as the relative inducer level increased. In the medium containing galactose only, induction of ${\beta}$-galactosidase synthesis by galactose increased with plasmid copy number. On the contrary, plasmid copy number did not affect significantly ${\beta}$-galactosidase synthesis in the medium containing both glucose and galactose (2% glucose＋2% galactose), which might be due to glucose repression caused by high glucose concentration. However, when the medium contained the relatively high inducer level (0.4% glucose＋0.8% galactose), ${\beta}$-galactosidase synthesis increased with plasmid copy number, indicating that the beneficial effect of higher galactose concentration was weaker than the repressive effect of higher glucose concentration.

• Microbiology and Biotechnology Letters
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• v.13 no.2
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• pp.169-172
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• 1985

The assimilability of glucose and xylose of Rhodopseudomonas K-7, whose hydrogen evolution has been characterized previously, was investigated under the anaerobic photosynthetic and the aerobic dark conditions. This organism is able to grow well in the medium containing glutamate and malate as organic substances under the anaerobic light condition. However, the substitution of glucose for malate retarded the growth rate, while the addition of glucose to the seed culture remarkably promoted the utilization of glucose added in the main culture. Optimal glucose concentration in the seed culture to induce glucose assimilability of the organism was around the concentration of 60 mM of glucose. Then, the seed culture grown in the medium containing 60 mM of glucose were inoculated in the medium containing 10, 20, 30, 60 and 100 mM of glucose respectively. The results were revealed that the consumable content of glucose was limited even though the high concentrations of glucose was contained in the medium. The consumption of considerable amount of glucose was observed when cultured under the aerobic dark conditions than the anaerobic illuminated conditions.

• Journal of Periodontal and Implant Science
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• v.38 no.3
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• pp.511-520
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• 2008

Purpose: Diabetes mellitus is a clinically and genetically heterogeneous group of metabolic disorders manifested by abnormally high levels of glucose in the blood. Mounting evidence demonstrates that diabetes is a risk factor for gingivitis and periodontitis. The circulating mononuclear phagocytes in diabetic patients with hyperglycemia are chronically exposed to high level of serum glucose. Thus, this study attempted to determine the effect of pre-exposure of monocytes and macrophages to high concentration of glucose on lipopolysaccharide (LPS)-induced production of pro-inflammatory mediators. Material and Methods: For this purpose, cells were cultured in medium containing normal (5 mM) or high glucose (25 mM) for 4-5 weeks before treatment for 24 h with LPS. LPS was highly purified from Porphyromonas gingivalis or Prevotella intermedia by phenol extraction. Result: Results showed that prolonged pre-exposure of cells to high glucose markedly increased LPS-stimulated NO secretion when compared to normal glucose. In addition to NO, high glucose also augmented LPS-stimulated IL-6, IL-8, and TNF-$\alpha$ secretion after cells were exposed to high glucose for 4 weeks. Conclusion: The present study demonstrates that pre-exposure of mononuclear phagocytes with high glucose augments LPS-stimulated production of pro-inflammatory mediators. These findings may explain why periodontal tissue destruction in diabetic patients is more severe than that in non-diabetic individuals.

• Journal of Adhesion and Interface
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• v.12 no.2
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• pp.56-61
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• 2011

In the present study, glucose-sensitive hydrogels using phenylboronic acid (PBA) without glucose oxidase and catalase were prepared. The swelling-shrinking behavior of the hydrogel according to the variation of pH and glucose and ionic concentrations was investigated. The swelling ratio of the hydrogel containing PBA increased with increasing the glucose concentration and the volume was very sensitively varied with the pH. However, the ionic concentration did not change significantly the relative swelling ratio on the hydrogel, indicating that the hydrogel was dimensionally stable.

• Journal of Electrical Engineering and Technology
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• v.4 no.1
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• pp.106-110
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• 2009

An amperometric glucose biosensor has been developed using viologen derivatives as a charge transfer mediator between a glucose oxidase (GOD) and a gold electrode. A highly stable self-assembled monolayer (SAM) of thiol-based viologen was immobilized onto the gold electrode of a quartz crystal microbalance (QCM) and GOD was immobilized onto the viologen modified electrode. This biosensor response to glucose was evaluated amperometrically in the potential of -300mV. Upon immobilization of the glucose oxidase onto the viologen modified electrode, the biosensor showed rapid response towards glucose. Experimental conditions influencing the biosensor performance, such as pH potential, were optimized and assessed. This biosensor offered excellent electrochemical responses for glucose concentration below ${\mu}$ mol level with high sensitivity and selectivity and short response time. The levels of the RSDs (<5%) for the entire analyses reflected the highly reproducible sensor performance. A linear calibration range between the current and the glucose concentration was obtained up to $4.5{\times}10^{-4}M$. The detection limit was determined to be $3.0{\times}10^{-6}M$.

• YAKHAK HOEJI
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• v.25 no.2
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• pp.49-55
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• 1981

To elucidate the effect of ginseng saponin on adrenaline-induced hyperglycemia and hyperlipidemia, ginseng saponin was administered before and after administration of adrenaline, and concentration of glucose, triglyceride(TG), and free fatty acid (FFA) as well as lipase activity in plasma was determined. 1) Glucose concentration was slightly increased by administration of ginseng saponin at 1 hour before and 10 minutes after adrenaline administration, but decreased by administration of ginseng saponin at 7 and 4 hours before adrenaline administration. TG and FFA concentration was also greatly inhibited by administration of ginseng saponin in advance. 2) When gineseng saponin 3, 10, 30mg/kg were administered 7 hours before adrenaline administration, glucose and TG concentration as well as lipase activity were inhibited in proportion to the dose of ginseng saponin, but FFA concentration was slightly inhibited. 3) It was suggested that protopanaxatriol group have potentiating effect on adrenaline induced hyperglycemia but protopanaxadiol group have inhibitory effect. And ginseng saponin seems to have strong inhibitory action on TG mobilization into blood and stimulatory effect on esterification of FFA in liver and adipose tissue.

• Journal of environmental and Sanitary engineering
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• v.23 no.2
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• pp.19-25
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• 2008

For measurement of tylosin, ammonia nitrogen, and glucose concentration during the culture of Streptomyces fradiae using Near Infrared Spectroscopy, the calibration using various mathematical models was performed and then, based on the linear model, the validation was carried out. In the case of sucrose concentration using the MLR method, the Standard Error of Prediction and Multiple correlation coefficient were 1.97, and 0.991, respectively. In the case of ammonia nitrogen concentration using the PLSR method, the Standard Error of Prediction and Multiple correlation coefficient were 0.13, and 0.990, respectively. In the case of tylosin concentration using the PLSR method, the standard Error of Prediction and Multiple correlation coefficient were 0.54, and 0.984, respectively.