• 한국약용작물학회지
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• 제27권2호
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• pp.108-114
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• 2019

Background: Rutin is decomposed by rutin-degrading enzymes (RDE) during the processing of buckwheat groats, resulting in a decrease in rutin content and a further increase in the bitterness of processed products. Thus, the present study aimed to examine RDE activity in groats and various tissues of domestic buckwheat varieties and to develop a method to reduce the loss of rutin during the groat processing. Methods and Results: RDE activity and isozymes patterns were determined in Tartary and common buckwheat. RDE activity, measured by quercetin production rate, was 273 and $70{\mu}g/g$ fresh weight/min in mature Tartary and common buckwheat groats, respectively. A total of six RDE isozymes were detected in mature groats of Tartary buckwheat on a non-denaturing gel. In Tartary buckwheat groats, RDE activity decreased by approximately 81 or 71% with roasting or steaming for 5 min respectively. As the roasting or steaming time increased to 30 min, RDE activity decreased by over 95%. These results indicated that RDE was inactivated in groats by roasting or steaming. When untreated Tartary buckwheat groats were kneaded with powder, RDE was activated and the quercetin production rate increased by 62%. However, when roasted groats were kneaded with powder, the quercetin production rate decreased by 93%, mainly due mainly to inactivation of RDE, as indicated by a decrease in band intensities of the six isozymes. Conclusions: These results suggested that the loss of rutin, due to RDE activity during processing, may be reduced by 71 to 100% by roasting or steaming groats for 5 to 30 min, due in large part to the inactivation of RDE isozymes.

• 한국연초학회지
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• 제20권1호
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• pp.80-86
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• 1998

Changes in activity and classification of esterase isozymes during the tire cycle or Plodia inteipunctella (Hiibner) were investigated by the native polyacrylamide gel electrophoresis. The stage specificity in esterase activity and isozyme pattern was observed throughout the larvalpupal-adult transformation. The activity esterase was highest at the 3-day old adult stage, and the lowest level at the prepupal stage. A total of 12 esterase bands were identified throughout the development, and the bands showing high enzyme activity was observed in the middle part of gel. Twelve esterases on the basis of inhibition by the three types of inhibitors (organophosphates, eserine sulfate and sulfhydryl reagents) were classified into three class, namely, carboxylesterase (CE), arylesterase (ArE) and cholinesterase (ChE), and these classes contained 7, 3 and 2 isozymes, respectively.

• 한국식품과학회지
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• 제23권4호
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• pp.442-446
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• 1991

Fuji 사과로부터 acetone 처리 및 CM-cellulose column chromatography를 통하여 3개의 peroxidase isozyme(peak I, II, III)을 분리하고 isoelectric focusing에 의하여 pI값이 각각 3.80, 8.82, 8.35임을 확인하였다. Peroxidase isozyme의 최적 pH는 guaiacol과 $H_{2}O_{2}$를 기질로 하였을 때 peak I이 pH5.0, peak II, III은 pH5.5 이었으며 최적온도는 peak I, II, III 모두 $40^{\circ}C$이었다. $70^{\circ}C$에서 각 isozyme의 D값은 660초, 1,320초, 600초로서 peak II isozyme이 가장 열에 안정하였다. 당(0.032 M)의 존재하에서는 sucrose와 lactose는 효소의 열안정성에 영향을 미치지 않았으나 fructose와 glucose는 열안정성을 현저하게 감소시켰다. 이는 환원당과 효소단백질의 상호작용에 기인한 것으로 생각된다.

• 한국육종학회지
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• 제40권1호
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• pp.26-30
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• 2008

전기영동법과 발색반응법 등의 장 단점 분석을 통해 가장 저렴한 비용으로 신속, 정확하게 lipoxygenase isozymes를 검정하는 분석체계를 확립하여 무비린내 나물콩 품종육성에 활용 가능할 것으로 보인다. 1. SDS-PAGE 전기영동법은 Lx-0, L-1, L-2, 및 L-123의 검정에는 효과적이었으나, L-3, L-13, 및 L-23의 검정에서는 분리능에 있어서 정확도가 떨어져 검정효율은 92.2%를 나타내었다. 2. 발색반응법을 이용한 lipoxygenase isozymes의 검정방법은 간편하고 신속하였으며 검정효율은 95.7%였다. 3. L-1과L-2가 존재하는 종실의 기질용액에서는 1분 이내에 methylene blue의 청색 반응용액을 탈색시켰으며 그 결과가 오랫동안 지속되었다. 4. L-3가 존재하는 종실의 용액에서는 20초 이내에 ${\beta}$-carotene의 황색 반응용액을 탈색시켰으나 그 결과가 오래 지속되지 않아 신속한 결과분석이 요구되었다. 5. L-1, L-2 및 L-3을 동시에 검정하기 위한 전체 시료량은 콩 종자 1알의 약 10 mg 정도이면 충분하였으며, 검정하지 않은 나머지 부분은 파종에 이용될 수 있으므로 F2 종자에서 lipoxygenase isozymes 결핍계통을 조기에 선발 가능하였다. 6. 발색반응법과 SDS-PAGE 전기영동법을 적절히 겸용하여 수행하게 되면 시료 분석에 소요되는 시간은 1인 100점에 6.5시간 재료비는 약 54,000원이 소요되어 이 시스템이 가장 효율적인 lipoxygenase 검정방법으로 판명되었다.

• Bulletin of the Korean Chemical Society
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• 제25권7호
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• pp.997-1002
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• 2004

A hydrogenperoxide sensor containing peroxidase extracted from horseradish was constructed and pH effect on its sensing ability was investigated. Current profiles of the biosensor with pH and the electrophoretic analysis showed that horseradish peroxidase consists of two isozymes. Assuming that it is a hypothetical twoisozyme mixture, the current profiles were deconvoluted into two Gaussians. Application of the new Michaelis-Menten equation connoting pH concept to this system enabled to find all the related dissociation constants of the isozyme-substrates and the isozyme-proton complexes and to determine pHs for the maximal isozyme activities.

• 약학회지
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• 제16권1호
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• pp.34-46
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• 1972

Lactate dehydrogenase isozymes in heart, kidney, liver and skeletal muscle of 15 species of vertebrate animals belonging to 5 classes were separated by cellulose acetate electrophoresis and the levels of them were measured and compared with each other. Lactate dehydrogenase isozyme patterns were different from each other among animal species and among tissues. The activity of LDH$_{5}$ was superior in anaerobic tissues such as liver and skeletal muscle, and the activity of LDH$_{1}$ was superior in aerobic tissues such as heart and kidney. The level of LDH of vertebrate animals of the 5 classes has found approximatry increasing in the following order: Pisces>Amphibia>Reptelia

• 미생물학회지
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• 제38권1호
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• pp.54-56
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• 2002

Induction of laccase isozymes under acidic stresses were determined in Trametes versicolor, Pleurotus ostreatus and Ganoderma lucidum isolated in Korea, and in Lentinus squarrosulrs isolated in Thai. When cultures of these fungi were transferred to acidic liquid media (pH 3.0-4.0), the activities of secreted extralcellular laccases were increased 60% and 400% in T. versicolor and G. lucidum respectively. However, there was no such induction in L. squarrosulus or P. ostreatus. In L. squarrosulus, different laccase isozymes in the electrophoretic mobilities were induced under acidic conditions.

• 분석과학
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• 제16권6호
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• pp.504-508
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• 2003

A carbon paste electrode was constructed with peroxidase extracted from Horseradish and the variation of the response of the sensor with pH was investigated. Current profiles showed two highest sensitivities at two pH values respectively. In addition, two bands were observed in the electrophoretic expansion. A coincidence of the two experimental results added support to the possibility that the biosensor has two different isozymes. Assuming that current profiles are the sum of two gaussians, we deconvoluted them and determined the optimum pH of peroxidase isozymes.

• 한국식품영양과학회지
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• 제17권4호
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• pp.348-357
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• 1988

갈변반응에 관여하는 polyphenol oxidase(PPO : EC 1.10.3.1)를 한국산 고구마(Ipomoea batatas, val : Hong-mi)로부터 추출하여 ammoniun sulfate 분획 및 DEAE-cellulose column chromatography법에 의하여 정제한 결과, 효소활동도는 23.1배였으며 enzyme activity 수율은 41.5%이었다. 이 효소는 일반 전기 영동법에 의하여 8개의 isozymes 으로, 또한 isolectric focusing에 의하여 pI가 각각 다른 12개의 isozymes으로 분리되었고 그 pI의 범위는 3.2-9.6이었으며, Isoelectric focusing에 의하여 분리된 각 isozyme의 specific activity는 6,000-46,700U/mg protein의 범위에 있었다. 고구마 중의 PPO는 $65^{\circ}C$이하에서는 안정하였으며 $65^{\circ}C$ 에서는 1분 가열에 의하여 약 50%의 효소활성이 상실되었고, pH optimum은 6.0-6.5이었다. o-diphenol이 이 효소의 가장 좋은 기질로서, 이 효소는 o-diphenolase임이 확인되었고, catechol에 대한 Km치는 6.7mM로 나타났다. 또한 이 효소에 대한 저해작용은 dithiothreitol, cysteine 및 ascorbic acid 순으로 크게 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권8호
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• pp.1060-1068
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• 2011

The LDH isozymes are key catalysts in the glycolytic pathway of energy metabolism. It is well known that the distribution of the LDH isozymes vary in accordance with the metabolic requirements of different tissues. The substrates required for energy production change noticeably at successive stages of testes development suggesting a significant flexibility in the expression of glycolytic enzymes. Therefore, expression of LHDA and LDHB mRNAs was examined in adult and prepubertal quail testis. The mRNA of both LDHA and LDHB were expressed and no significant difference was observed in prepubertal testes. The mRNA levels of LDHB significantly increased during testicular development. In the adult testis, LDHA mRNA was not expressed. Expression studies revealed the presence of different LDH isozymes during testicular development. In contrast, electrophoresis of both testicular samples revealed only single band at a position indicative of an extreme type of LDH isozyme in quail testes. Furthermore, nucleotide and amino acid sequence analysis revealed significant similarity to chicken, duck and rock pigeon. These sequence results confirmed the similarity of LDHA and LDHB subunit protein in different avian species.