• Food Science and Biotechnology
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• 제17권2호
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• pp.417-420
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• 2008

Rheological properties of sweet potato starch (SPS)-glucose composites (5%, w/w) at different concentrations (0, 10, 20, and 30%, w/w) of glucose were investigated in steady and dynamic shear. The steady shear rheological properties of SPS-glucose composites were determined from rheological parameters for power law and Casson flow models. At $25^{\circ}C$ all the samples showed a pronounced shear-thinning behaviors (n=0.29-0.37) with high Casson yield stress. In general, the presence of glucose resulted in the decrease in consistence index (K), apparent viscosity (${\eta}_{a,100}$), and yield stress (${\sigma}_{oc}$). Storage (G') and loss (G") moduli increased with an increase in frequency ($\omega$), while complex viscosity (${\eta}*$) decreased. Dynamic moduli (G', G", and ${\eta}*$) of the SPS-glucose composites at higher glucose concentrations (20 and 30%) were higher than those of the control (0% glucose) and also increased with increasing glucose concentration from 10 to 30%. The effect of glucose on steady and dynamic shear rheological properties of the SPS pastes appears to greatly depend on glucose concentration in the range of 10-30%.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.598-601
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• 2001

Citrobacter sp. Y19 was studied for $H_2$ production from glucose in batch culture. Important conditions studied include phosphate concentration, temperature, glucose concentration, and gas-phase replacement. Optimal $H_2$ production was observed at 140 - 180 mM of phosphate and $36^{\circ}C$. When glucose concentration increased from 0.1 to 5% (w/v), $H_2$ production increased up to 2% and remained constant thereafter. Intermittent purging of the reaction bottle with Ar gas stimulated the $H_2$ production by alleviating the inhibition by $H_2$. The maximum productivity was observed to be 113.2 ml $H_2$/h-1.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.594-597
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• 2001

RhodopseudolllOllas palustris P4 was studied for $H_2$ production from glucose in batch culture. Important conditions studied include phosphate concentration, initial pH, temperature, glucose concentration, and gas-phase replacement. Optimal $H_2$ production was observed at 60 - 300 mM of phosphate and 7.8 - 8.6 of initial pH. The effect of culture temperature was negligible When glucose concentration increased from 0.1 to 5% (w/v), $H_2$ production increased up to 2% and remained constant thereafter. Intermittent purging of the reaction botlle with Ar gas stimulated the Hl production by alleviating the inhibition by $H_2$. The maximum productivity was 111.1 ml $H_2$/h-1.

• Preventive Nutrition and Food Science
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• 제18권1호
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• pp.11-17
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• 2013

Dysfunction of endothelial cells is considered a major cause of vascular complications in diabetes. In the present study, we investigated the protective effect of Padina arborescens extract against high glucose-induced oxidative damage in human umbilical vein endothelial cells (HUVECs). High-concentration of glucose (30 mM) treatment induced cytotoxicity whereas Padina arborescens extract protected the cells from high glucose-induced damage and significantly restored cell viability. In addition, lipid peroxidation, intracellular reactive oxygen species (ROS), and nitric oxide (NO) levels induced by high glucose treatment were effectively inhibited by treatment of Padina arborescens extract in a dose-dependent manner. High glucose treatment also induced the overexpressions of inducible nitric oxide synthase (iNOS), cyclooxygenase- 2 (COX-2) and NF-${\kappa}B$ proteins in HUVECs, but Padina arborescens extract treatment reduced the over-expressions of these proteins. These findings indicate the potential benefits of Padina arborescens extract as a valuable source in reducing the oxidative damage induced by high glucose.

• Preventive Nutrition and Food Science
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• 제18권1호
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• pp.38-44
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• 2013

The protective effect of Polyopes lancifolia extract on high glucose-induced oxidative stress was investigated using human umbilical vein endothelial cells (HUVECs). High concentration of glucose (30 mM) treatment induced HUVECs cell death, but Polyopes lancifolia extract, at concentrations of 25, 50, and $100{\mu}g/mL$, protected cells from high glucose-induced damage. Furthermore, thiobarbituric acid reactive substances, intracellular reactive oxygen species, and nitric oxide levels increased by high glucose treatment were effectively decreased by treatment with Polyopes lancifolia extract in a dose-dependent manner. Also, Polyopes lancifolia extract treatment reduced the overexpressions of inducible nitric oxide synthase, cyclooxygenase-2, and nuclear factor-kappa B proteins activation that was induced by high glucose in HUVECs. These results indicate that Polyopes lancifolia extract is a potential therapeutic material that will reduce the damage caused by high glucose-induced-oxidative stress associated with diabetes.

• Applied Biological Chemistry
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• 제34권1호
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• pp.67-74
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• 1991

내당 내알콜성 균주인 S. cervisiae D1을 이용하여 알콜 발효를 할 때 ethanol 생산성을 증대시키기 위하여 발효시 $Ca^{2+}$을 첨가하여 발효에 미치는 영향에 관해서 연구한 결과 다음의 결론을 얻었다. 초기 glucose 농도를 400g/l로 하였을 때 $Ca^{2+}$에 의해 ethanol 생산성이 증가하였고 생균수도 증가하였으며 최적 첨가 농도는 0.8 mM이었다. 초기 glucose농도를 달리하고 발효하였을 때는 $Ca^{2+}$의 영향이 초기 glucose 농도가 높을수록 켰다. Ethanol 첨가에 의해 비증식 속도가 감소하였지만 $Ca^{2+}$을 0.8 mM 첨가시 비증식 속도의 저해가 감소되었다. 또한 ethanol을 첨가하지 많았을 때는 $Ca^{2+}$을 첨가한 경우와 첨가하지 않은 경우의 비증식 속도가 같았다. Ethanol 첨가 농도에 의해 사멸 속도가 증가하였으나 $Ca^{2+}$을 0.8 mM 첨가시 비사멸 속도가 감소하였다. Acidification curve에서도 ethanol 첨가시 final pH가 증가하였으나 $Ca^{2+}$을 0.8 mM 첨가하면 final pH가 감소하였다. 따라서 $Ca^{2+}$ 첨가시 ethanol에 대한 내성이 더 증가된다는 것을 알 수 있었다.

• 약학회지
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• 제13권1호
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• pp.16-21
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• 1969

When ultrasonic wave with barium titanate as an ultrasonic transducer (96.84kc, 1.4kv, 240mA) was applied to a dilute glucose solution, glucose was oxidized to glucuronic acid. It was found that the lower the glucose concentration, the higher the oxidation rate. The aeration and the presence of ferrous sulfate as a catalyst were found to increase the rate. The optimal duration for applying the wave to the solution was found to be six hours.

• 한국미생물·생명공학회지
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• 제28권2호
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• pp.105-110
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• 2000

강력한 함암작용을 나타내는 단백다당체를 생산하는 Phellinus linteus WI-001 균주를 대상으로 배양학적 특성 및 초기 배양배지의 탄소원인 glucose 농도에 따른 균사체 생산성을 조사하였다. 배양중 최적 pH와 온도는 각각 5.5와 28$^{\circ}C$인 것으로 나타났다. 특히 pH의 경우 전 배양기간에 걸쳐 5.5에서 6.5의 비교적 좁은 범위에서 변화하였다. 초기 glucose 농도를 0.5%, 1%, 2%, 3% 및 4%에서 균사체 생산량 및 세포비성장속도를 조사한 결과 최종 균사체 생산량은 glucose 농도가 증가할수록 높게 나타났으나, 세포비성장속도가 가장 빠르게 나타나는 초기 1% glucose 조건하에서 배양하다가 추가로 glucose를 간헐적 또는 지속적으로 공급하는 전략으로 생산성 향상을 시도하였다. 그 결과 회분식 배양에 비해 간헐적 공급방식에서는 28% 지속적 공급방식에서는 42%의 수율이 증가되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권3호
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• pp.365-372
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• 2007

This study was conducted to determine effects of salinomycin (SL) on feeding-induced changes in glucose kinetics and blood VFA concentrations in sheep fed a high-roughage diet. Four sheep were fed the diet with or without 20 mg/kg diet of SL once daily for 21 d. Glucose entry and utilization rates were determined during the prefeeding and 3 h postfeeding periods, using a [$^{13}C_6$]glucose dilution method and non-steady state equations. Ruminal characteristics and concentrations of blood VFA, plasma glucose and insulin were also measured during the same periods. A feeding-induced increase in ruminal total VFA concentration tended to be inhibited (p<0.10) with SL, although ruminal pH was unaffected (p>0.10) with SL or by feeding. Salinomycin decreased (p<0.05) acetate proportion and increased (p<0.05) propionate proportion in the rumen, but did not modify these changes in response to feeding (p>0.10). A feeding-induced increase in blood acetate concentration was attenuated (p<0.05) with SL. Salinomycin tended to increase (p<0.10) blood propionate concentration without modifying its response patterns to feeding (p>0.10). Plasma concentrations of glucose or insulin were unaffected (p>0.10) with SL. Salinomycin tended to enhance (p<0.10) glucose entry and utilization rates. Feeding also enhanced (p<0.01) both rates, whereas their interactive effect was not detected (p>0.10). We conclude that SL possibly enhances whole body glucose entry and utilization with an increase in blood propionate concentration in sheep given a high-roughage diet, although SL does not appear to affect their responses to feeding.

• 접착 및 계면
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• 제12권2호
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• pp.56-61
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• 2011

본 연구에서는 glucose oxidase와 catalase를 혼합 분산시키지 않고 phenylboronic acid (PBA)을 이용하여 glucose에 반응하는 hydrogel을 합성하였으며, 합성된 hydrogel의 pH 및 glucose 농도 및 이온 농도에 따른 팽윤-수축 거동에 대하여 연구하였다. PBA를 사용하여 합성된 hydrogel은 glucose의 농도에 따라 팽윤비가 증가되는 것으로 나타났으며, pH의 변화에 따라 급격한 부피 변동성을 나타냈다. 그러나 이온농도에 따른 부피의 변화는 상대적으로 작게 나타난 것으로 보아 안정적인 hydrogel임을 확인할 수 있었다.