• 한국수정란이식학회지
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• 제20권2호
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• pp.113-121
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• 2005

This study was conducted to investigate the effects of different hexoses (glucose, mannose, galactose and fructose) on in vitro development of parthenogenetic embryos in the pigs. When the parthnogenetic embryos were cultured in medium with concentrations of 5mM glucose or 1mM galactose, the rates of embyos developed to morula and blastocyst stages were significantly higher than those in another culture conditions (P<0.05). However, high concentration of galactose inhibited development to morula and blastocyst stages. Addition of hexoses at early stage of porcine parthenogenetic embryos were effective for in vitro development. Especially, the embryos cultured in medium with glucose at early stage were effective for development to 2-cell $(72\%)$ and blastocyst $(19\%)$ stages compared with embryo cultured without glucose. From the present results, it is suggested that development of porcine parthenogenetic embryos can improve in medium with 5mM glucose. The concentration of 1mM galactose was also effective for development of porcine parthenogenetic embryos. It also show that parthenogenetic embryos cultured with glucose at early stage can improve in vitro development.

• 한국미생물·생명공학회지
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• 제6권4호
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• pp.161-165
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• 1978

자연계에서 유기산을 생성하는 균주 11 군주를 분리하여 그 중에 구연산 생성균 1종을 선정하여, 동정한 결과 Aspergillus niger로 나타났다. 분리된 균주로 500ml 삼각 flask에 Sakaguchi 배지 100ml를 넣고 3$0^{\circ}C$에서 발효한 결과 구연산이 17g/ι가 생성되었다. 또한 Sakagnchi 배지를 개량한 결과 즉 배지적응, peptone첨가, 통기 효과, methanol첨가 및 포도당 첨가 결과 구연산이 35g/ι가 생성되었다

• The Korean Journal of Ecology
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• 제17권4호
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• pp.425-434
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• 1994

After two highly weathered soils were treated with glucose, ammonium nitrate, monobasic potassium phosphate and biocides, and incubated for 4 or 6 weeks, adsorption tests were carried out to determine their effect on P adsorption. Glucose addition generally decreased P adsorption. The addition stimulated microbial activity, which might contribure to the reduced adsorption, probably through chelation and anion competition. Consistent endency was not observed with N treatment. Addition of P initially decreased P adsorption, probably through blockage of adsorption sites. Biocides generally decreased adsorption, probably because the microbes that 몬 been killed. Soil 1 with naturally lower levels of C and higher levels of aluminium adsorbed more P than soil 2. These results suggest that in highly weathered soils, which are low in available P and high in exchangeable Al, cultivation techniques which increase soil organic matter will also result in higher levels of plant-available P.

• 한국식품영양과학회지
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• 제19권4호
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• pp.301-304
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• 1990

Factors affecting thermal inactivation and reactivation of korean radish peroxidase were inves-tigated,. The enzyme was stable below pH4.0 and above pH 8.0 The thermostablity of the enzyme was increased by addition of glucose sodium chloride and albuminl The inactivated enzyme by heat treatment was reactivated at room temperaturem The optimal pH for reactivation of the enzyme was pH of 9.0 The reactivation rate of the enyme was not afected by addition of glucose sodium chloride and albumin, The reactivation was completely inhibited by addition of sulfhydryl reagent such as dithiothreitol.

• Mycobiology
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• 제33권1호
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• pp.23-29
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• 2005

The effects of different concentrations of three amino acids as carbon and or nitrogen sources on mycelial dry weights, changes in pH values of synthetic medium, ammonia secretion and extracellular protease activity by three zoosporic fungi, pathogens of fish and shellfish, were studied. As compared with the control, the addition of isoleucine and aspartic acid as nitrogen sources were generally stimulative for mycelial dry weight production whereas phenylalanine was inhibitory irrespective to the tested fungal species. When amino acids served as carbon and nitrogen sources, the mycelial dry weights of the three fungi were increased (mostly non-significantly) relative to untreated control but weights were decreased as the concentrations of the three amino acids raised. The addition of individual amino acids as carbon and nitrogen sources to the medium significantly increased pH values of the medium comparable to the control. The addition of each of the three amino acids as carbon and nitrogen sources to the medium significantly induced ammonia secretion by the three species of zoosporic fungi. Ammonia secretion in synthetic medium amended with amino acids as nitrogen source raised by the three zoosporic fungi relative to untreated control except in case of Achlya racemosa treated with isoleucine. Extracellular protease activity was almost promoted in case of Achlya proliferoides and Saprolegnia furcata cultures treated with isoleucine and aspartic acid individually in presence of glucose and vice versa in case of phenylalanine. However, extracellular protease activity of A. racemosa decreased compared with the control at various concentrations of isoleucine and both phenylalanine and aspartic acid assumed inconsistent effects. Extracellular protease activity of the three zoosporic fungi in the medium devoid of glucose varied depending upon zoosporic fungal species, the tested amino acid and the applied concentrations. The values of protease activity were approximately less two folds than that obtained in presence of glucose.

• 공업화학
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• 제26권1호
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• pp.47-52
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• 2015

본 연구에서는 다중벽탄소나노튜브(multi-walled carbon nanotube, MWCNTs) 기반 바이오센서 전극의 포도당 산화효소(glucose oxidase, GOD) 담지능을 높여 그 민감도를 개선하고자 그래핀 옥사이드(graphene oxide, GO)를 첨가하여 전극을 제조하였다. GO 첨가로 인하여 MWCNTs의 분산뿐만 아니라 전극의 친수성 및 표면에너지가 증가하였다. 또한, MWNCTs 0.05 g에 GO 0.05 g를 첨가하였을 때 $K_m$ (Michaelis-Menten constant)이 0.105로 가장 높은 값을 나타냈음에도 불구하고 GOD 담지능이 높아졌으며, 민감도가 $121{\mu}A\;mM^{-1}$까지 향상됨을 알 수 있었다. 이러한 실험 결과는 GO첨가에 의한 MWCNTs의 분산 안정성 향상, MWCNTs 전극 표면에서 친수성으로 개질 및 표면 자유에너지 증가가 GOD 담지능에 영향을 미친 것으로 사료된다.

• Applied Biological Chemistry
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• 제14권2호
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• pp.117-120
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• 1971

Saccharomyces rouxii $T_9$의 생육에 미치는 당류의 영향과 내당성에 대하여 실험한 결과는 아래와 같다. (1) 생육에 가장 효과 있는 당류로는 inulin, fructose, maltose 등이였다. (2) glucose, saccharose, galactose, arabinose 등은 무염배지에서 보다 20% 식염함유배지에서 더욱 효과가 있었으며 fructose, inulin, xylose, sorbitol, raffinose, mannitol, mannose, trehalose, rhamnose 등은 무염배지에서 더욱 효과가 있었다. (3) maltose 와 lactose는 $5{\sim}10%$ 첨가 했을 경우 식염함유 배지에서 양호하였으며 15%이상 첨가 했을 때는 무염배지에서 더욱 양호하였다. (4) 일반작으로 배지의 당농도는 $15{\sim}30%$ 범위내에서 생육이 양호하였다. (5) glucose는 80%, saccharose와 maltose는 90% 농도에서 생육하였다.

• 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.

• Reproductive and Developmental Biology
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• 제37권2호
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• pp.65-73
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• 2013

The objective of this study was to examine the effects of high concentrations of glucose on porcine parthenotes developing in vitro. Addition of 55 mM glucose to the culture medium of embryos at the four-cell-stage significantly inhibited blastocyst formation, resulting in fewer cells in blastocyst-stage embryos and increased levels of apoptosis and autophagy compared to control. Quantitative reverse transcriptase (RT) PCR analysis revealed that the expression of pro-apoptotic genes (Caspase 3, Bax and Bak) and autophagy genes (Atg6 and Atg8/Lc3) were increased significantly by the addition of 55 mM glucose to the culture medium compared to control. MitoTracker Green fluorescence revealed a decrease in the overall mitochondrial mass compared to control. However, the addition of 55 mM glucose had no effect on mRNA expression of the nuclear DNA-encoded mitochondrial-related genes, cytochrome oxidase (Cox) 5a, Cox5b and Cox6b1. These results suggest that hyperglycemia reduced the mitochondrial content of porcine embryos developing in vitro and that this may hinder embryonic development to the blastocyst stage and embryo quality by increasing apoptosis and autophagy in these embryos.

• Applied Biological Chemistry
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• 제38권5호
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• pp.376-381
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• 1995

내열성 alkaline phosphatase의 탐색을 위해 극도호열균중에서 Thermus caldophilus GK24 균주를 선정하였다. 이 균주를 이용하여 basal salts에 sodium glutamate, bactotryptone, glucose 및 yeast extract를 첨가시킨 배지에서 alkaline phosphatase 생산을 검토하였다. 그 결과 sodium glutamate가 alkaline phosphatase 유도에 효과적인 것으로 판명되었다. Alkaline phosphatase 생산을 위한 최적유도용 배지는 basal salts에 0.3% sodium glutamate, 0.2% bactotryptone, 0.5% glucose를 첨가한 것으로 효소활성은 기본배지보다 약 6배, 표준배지 보다는 약 27.5배 증가하였다. T. caldophilus GK24 alkaline phosphatase는 유도효소로 판명되었다. 무기인산 결핍시에 효소가 생산되며, 생육배지에 무기인산을 첨가하면 효소합성에 저해효과가 있었다.