• KSBB Journal
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• 제13권5호
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• pp.621-625
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• 1998

The raw starch hydrolysis by amylase prepared from alkaline-tolerant Bacillus sp. were investigated. Degree of hydrolysis(%) of 5%(w/v) raw rice, corn and potato starch by this enzyme were about 40, 25 and 20%, respectively. The hydrolysis action on raw starch by change of blue value was similar to the action pattern of exo ${\beta}$-amylase. The hydrolysis products of rice starch were mainly glucose and maltose. Oligosaccarides were also detected. From the above results, this enzyme was considered as exo type ${\alpha}$-amylase. This enzyme activity on the raw starch and the gelatinized starch were 28.40 and 86.60 IU/mg protein, respectively, and the ratio of raw starch-digesting activity to gelatinized starch-digesting activity (raw starch digestivity) was about 32%. The Km values for the raw and the gelatinized starch were 4.22 and 3.0mg/mL, respectively, and the VmaX values were 0.20 and 0.31mg/mL/min, respectively.

• 대한약리학회지
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• 제12권2호
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• pp.7-11
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• 1976

A portion of duodenum laid pancreatic duct opening were perfused continuously with physiological saline under urethane anesthesia in rats. The pancreatic amylase secretory response to caerulein was studied with autonomic blockers, such as phenoxybenzamine, dibenamine, phentolamine, hexamethonium, propranolol, atropine, and cyproheptadine. The pancreatic amylase output to caerulein, 7.5ng/kg i.v., was markedly increased and the value was approximately three times greater than control. The caerulein-stimulated pancreatic amylase secretion was significantly decreased by i.v. phenoxybenzamine and propranolol treatment, but not by phentolamine or dibenamine. Secretory response of pancreatic amylase to caerulein was not affected by i.v. atropine, hexamethonium or cyproheptadine. These result lead to the conclusion that phenoxybenzamine may inherently inhibit the secretory response of pancreatic amylase to caerulein, and this effect was not related with ${\alpha}-adrenergic$ receptor blocking action.

• 한국미생물·생명공학회지
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• 제14권5호
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• pp.359-363
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• 1986

본 실험의 목적은 starch의 alcohol발효에 있어서 전분의 $\alpha$-1.4 linkage을 분해하여 alcohol발효를 하는 S diastaticus와 전분 중의 $\alpha$-1.4, $\alpha$-1.6 linkage를 모두 분해할 수 있는 C. tropicalis 간의 이속간의 protoplast fusion을 시켰다. 이때 세포 융합의 빈도는 $10^{-5}$-$10^{-6}$이였으며, 이틀 융합체중 amylase 생성능과 유전적으로 안정한 융합체를 분리하였다. fusant의 성질을 조사하기 위하여 탄소원 자화능을 조사한바 parent와 달리 탄소원 자화능이 일부 보완됨을 보였고 또한 fusant는 원 parent보다 세포의 크기가 클 뿐만아니라, DNA함량도 많았다. spore형성능은 S. diastaticus A4는 spore를 형성하나 C. tropicalis는 형성할 수 없는 반면에 fusant는 형성하였고, Cu$^{++}$ 내성과 NaCl 내염성도 조사하였는데 fusant는 parent의 중간 성질을 가졌다. Fusant의 증식율을 조사하기 위하여 생육도를 조사한 결과 Parent보다 유도기가 길었음을 알았다.

• Preventive Nutrition and Food Science
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• 제20권2호
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• pp.88-93
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• 2015

The purpose of this research was to investigate the inhibitory effect of jicama extract on ${\alpha}$-glucosidase activity, ${\alpha}$-amylase activity, and postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. Jicama extract showed prominent inhibitory effects against ${\alpha}$-glucosidase and ${\alpha}$-amylase. The $IC_{50}$ values of jicama extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase were $0.083{\pm}0.004$ and $0.091{\pm}0.017mg/mL$, respectively. The increase in postprandial blood glucose levels was more significantly suppressed in the jicama extract-administered group than in the control group of both STZ-induced diabetic and normal mice. Blood glucose levels of the control group increased to $383.75{\pm}11.54$ and $402.50{\pm}15.32mg/dL$ at 30 and 60 min after a meal and decreased to $349.67{\pm}11.62mg/dL$ at 120 min. However, postprandial blood glucose levels were significantly decreased, when diabetic mice were fed with jicama extract ($342.00{\pm}15.73$, $367.00{\pm}13.00$, and $329.67{\pm}12.43mg/dL$ at 30, 60, and 120 min, respectively). Furthermore, the area under the curve was significantly decreased with jicama extract administration in diabetic mice (P<0.05). Therefore, these results indicate that jicama extract may help decrease postprandial blood glucose level by inhibiting ${\alpha}$-glucosidase.

• 수산해양기술연구
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• 제51권1호
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• pp.71-78
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• 2015

In order to deduce an objective evaluation method of motion seasickness incidence (MSI) by ship motions during underway in irregular waves and to present the fundamental data of passenger comfort on the yacht and the passenger ship according to the result, the MSI of the trainees by the questionnaires was analysed and compared with the rate of variation of salivary ${\alpha}$-amylase activity (VSAA) on the training ship "A-ra ho" of Jeju national university. Relationship between rate of variation (x) by salivary ${\alpha}$-amylase activity and motion seasickness incidence (y) was described by the equation, MSI(%) = 0.6073 x + 12.189 including the correlation coefficient ($R^2=0.9853$). The result obtained through the rate of variation of salivary ${\alpha}$-amylase activity which was the quantitative evaluation method for ship motions causing seasickness was most affected by z-vertical acceleration and occurred within the frequency range 0.1 to 0.3Hz centered on 0.2Hz, and the simulation result based on this finding showed the motion seasickness rate at approximately 4% lower than the rate obtained through the survey.

• BMB Reports
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• 제35권6호
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• pp.568-575
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• 2002

An $\alpha$-amylase (EC 3.2.1.1) was purified that catalyses the production of a high level of maltose from starch without the attendant production of glucose. The enzyme was produced extracellularly by thermophilic Streptomyces sp. that was isolated from Thailand's soil. Purification was achieved by alcohol precipiation, DEAE-Cellulose, and Gel filtration chromatographies. The purified enzyme exhibited maximum activity at pH 6-7 and $60^{\circ}C$. It had a relative molecular mass of 45 kDa, as determined by SDS-PAGE. The hydrolysis products from starch had $\alpha$-anomeric forms, as determined by $^1H$-NMR. This maltose-forming $\alpha$-amylase completely hydrolyzed the soluble starch to produce a high level of maltose, representing up to 90%. It hydrolyzed maltotetrose and maltotriose to primarily produce maltose (82% and 62%, repectively) without the attendant production of glucose. The high maltose level as a final end-product from starch and maltooligosaccharides, and the unique action pattern of this enzyme, indicate an unusual maltose-forming system. After the addition of the enzyme in the bread-baking process, the bread's volume increased and kept its softness longer than when the bread had no enzyme.

• 한국식품과학회지
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• 제32권3호
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• pp.610-617
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• 2000

높은 난소화성 획분을 갖는 난소화성 덱스트린은 열처리 덱스트린의 효소 가수분해액을 에탄올 또는 강산성 양이온 교환수지(UBK 530)로 처리함으로써 제조하였다. 난소화성 획분, 식이섬유 및 수출을 고려하여 ${\alpha}-amylase$와 amyloglucosidase를 반응시킨 가수분해액으로부터 난소화성 덱스트린을 제조하기 위한 에탄올 처리의 최적 조건은 에탄올을 30%(w/w) 효소 반응액에 고형분 대비 5배로 첨가하여 상온에서 3시간 동안 방치시키는 공정이었다. 포도당을 포함하는 저분자 당류와 고분자 당류를 강산성 양이온 교환수지에 의해 분리한 결과 내열성 ${\alpha}-amylase$와 amyloglucosidase에 의한 초기 효소 반응액은 43.6%의 DPI(glucose)과 51.5%의 DP4+(maltotetaos이상)를 나타낸 반면, 양이온 교환수지에 의해 초기 효소 반응액의 50%까지 분취한 난소화성 덱스트린은 7.1%의 DPI(glucose)과 91.2%의 DP4+(maltoteoaose이상)를 나타내었다. 따라서, 초기 효소 반응액의 난소화성 획분 44.5%는 저분자 당류의 분리 후 78.9%까지 증가하였다.

• 한국식품과학회지
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• 제32권3호
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• pp.618-628
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• 2000

열처리 덱스트린을 내열성 ${\alpha}-amylase$로 가수분해함으로써 난소화성 텍스트린 I을 제조하였다. 황색 덱스트린으로부터 제조한 난소화성 덱스트린 I의 난소화성 획분과 식이섬유 함량의 평균치는 각각 50%와 25%였다. 또한, 열처리 덱스트린의 효소반응액으로부터 에탄올 처리에 의해 glucose를 포함하는 저분자의 당류를 제거함으로써 난소화성 덱스트린 II를 제조하였다. 초기 효소반응액의 80% 이상의 glucose와 maltose가 제거되어 난소화성 획분과 식이섬유 함량이 증가하였다. ${\alpha}-amylase$ 및 amyloglucosidase에 의한 황색 덱스트린의 가수분해액의 에탄올 침전으로 제조된 난소화성 덱스트린이 다른 효소 조합보다 높은 함량의 난소화성 획분 및 식이섬유를 나타내었으며, 각각 평균 83.6%와 62.8%였다. 따라서, 전분 가수분해 효소에 저항성을 갖는 난소화성 덱스트린은 열처리 덱스트린으로부터 용이하게 제조될 수 있으며, 수용성 식이섬유로서의 생리효과를 발휘할 수 있을 것으로 추정되었다.

• 한국식품조리과학회지
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• 제33권2호
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• pp.181-189
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• 2017

Purpose: This study was conducted to examine the effects of the starch concentration of filled hydrogel and the addition of ${\alpha}-amylase$ and simulated mastication processing in an oral phase on lipid digestion and ${\beta}-carotene$ bioaccessibility of filled hydrogels. Methods: Lipid digestion and ${\beta}-carotene$ bioaccessibility of the filled hydrogels were measured after the samples were passed through an in vitro gastrointestinal tract model consisting of oral, gastric, and small intestinal phases. Results: The initial rate and final extent of lipid digestion were higher in the filled hydrogels than in the emulsion when the filled hydrogels were treated in an oral phase without simulated mastication processing and addition of ${\alpha}-amylase$, regardless of starch concentration. However, when the filled hydrogels were minced using mortar and pestle for 2 min and were exposed to ${\alpha}-amylase$, the filled hydrogel fabricated with 5% starch showed the lowest lipid digestion rate and extent compared to the emulsion and other filled hydrogels. Bioaccessibility of ${\beta}-carotene$ was higher in the filled hydrogels than in the emulsion, regardless of the digestion method performed in an oral phase and starch concentration. However, there were appreciable differences in bioaccessibility of the filled hydrogels depending on whether or not simulated mastication and addition of ${\alpha}-amylase$ were employed. Conclusion: These results suggested that the rheological properties of initial filled hydrogels and simulated mastication processing in an oral phase plays an important role in determining the lipid digestion and ${\beta}-carotene$ bioacccessibility entrapped within filled hydrogels.

• KSBB Journal
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• 제9권4호
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• pp.428-435
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• 1994

탄소원으로 초기 glucose 농도와 초기 maltose 농도를 5g/$\ell$, 109/$\ell$, 20g/$\ell$ 로 한 후 Bacillus a amyloliquefaciens(ATCC 23350 ) 균주를 이용하여 플라스크 배양시의 세포 성장과 생성물 생성에 대한 연구를 수행하였다. 균주의 최대 건조세포농도는 초기 maltose 농도가 증가할수록 증가하였으나, glu­c cose에서는 초기 농도가 109/$\ell$일 때 가장 높았다 최대 비성장속도는 초기 glucose농-토가 109/$\ell$ 일 때 $0.060(hr^{-1})$로 가장 높으며, maltose에서는 초기 농도가 5g/P 얼 때 $0.042(hr^{-1})$이였다. 균주에 의해 생성되는 최대 a-amylase 생산은 초기 maltose 농도가 109/P 얼 때 l49.0unit/ml로 가장 높았으며, 초기 maltose 농도가 증가할수록 증가하였다. 최대 비생성속도는 초기 maltose 농도가 5g/$\ell$ 일 때 3.26unit/ mg- hr로 가장 높았으며 , glucose보다는 maltose에서 더 높았다. 균주에 의해 생성되는 최대 ${\alpha}$-acetic acid는 탄소원의 초기 농도가 증가함에 따라 감소하며, 초기 glucose 농도 109/$\ell$ 일 때 0.94g/$\ell$ 로 가장 많이 생성되였고, lactic acid는 탄소원의 초 기 농도가 증가할수록 증가하였으며, 초기 maltose 농도가 20g/$\ell$일얼 때 8.20g/$\ell$ 로 가장 많이 생성되였 다.