• 생명과학회지
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• 제17권9호통권89호
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• pp.1260-1265
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• 2007

자석으로 분리가 가능한 ${\alpha}-Amylase$가 코팅된 나노고분자를 제조하여 녹말의 분해공정에 활용하였다. 본 연구에서 개발된 고정화 효소의 안정성은 크게 증가하여 상온에서 200rpm으로 교반하면서 보관한 경우 30일 동안에 92.7%의 활성도를 유지하였다 . 고정화 효소를 자석을 이용하여 재사용한 경우 10 회 동안 사용했을 경우 95.2%의 활성도 회수율을 보 여 효소의 재사용 가능성을 확인시켜 주었다 . 고정화 효소 0.5mg을 사용하여 녹말 분해 공정 에 활용하였을 때 2 ml의 40 g/l 녹말 용액을 40분만에 완전히 분해 시켰다, 이러한 고정화 효소를 사용하여 연속 효소반응기를 개발하여 녹말 분해공정에 활용한 결과 체류시간을 1시간으로 하였을 때 녹말 30 g/l를 76% 분해시켜 산업적으로 활용 가능성을 보여 주었다.

• 한국환경과학회지
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• 제14권3호
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• pp.359-366
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• 2005

Starch was crosslinked with epichlorohydrin. Crosslinked starch-filled waterborne acrylate (CSWAC) films were prepared by blending this crosslinked starch with waterborne acrylate. The thermal and mechanical properties of these films were investigated by thermogravimetric analysis (TGA), tensile strength and elongation test. The biodegradability was also studied by determination of reduced sugar products after enzymatic hydrolysis and the surface morphology was investigated by scanning electron microscopy (SEM). The CSW AC film showed significantly higher tensile strength and elongation than those of starch-filled waterbonre acrylate (SWAC). The biodegradability of this film was higher than that of native starch-filled acrylate film, and was increased by the addition of crosslinked starch to the acrylate film.

• Journal of Animal Science and Technology
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• 제62권6호
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• pp.956-958
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• 2020

Lactobacillus plantarum SK156 was isolated from traditional Korean food. The genome of SK156 strain consists of a circular chromosome (3,231,383 bp) with guanine (G) + cytosine (C) content of 44.56%. Among the predicted 2,991 protein-coding genes, the genome included genes encoding for α-amylase, which hydrolyzes α-bonds of polysaccharides. Genomic sequencing of L. plantarum SK156 will give information on the mechanism involved in the enzymatic degradation of polysaccharides and its application for improving feed efficiency.

• 생명과학회지
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• 제18권7호
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• pp.1005-1010
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• 2008

최근 당뇨병 환자가 급속히 증가하고 있으나, 지속적이고 적절한 치료가 어려워 당뇨병성 합병증의 발생을 증가시키고 있다. 당뇨병 발병 이후의 치료는 완치가 거의 불가능하기 때문에 증상을 개선시키고 급만성 합병증을 막는 이차적 예방에 중점을 두고 있다. 따라서 항당뇨 활성을 가지면서 식용 가능한 천연자원의 개발이 절실히 필요하다. 본 연구에서 약용식물로 알려진 사방오리나무에 대해 아직까지 보고가 없었던 항당뇨 활성에 대해 조사하였다. Pancreatin와 salivary ${\alpha}-amylase$ 에 대해 MeOH 추출물과 HX 분획물이 ${\alpha}-amylase$를 효과적으로 억제하였으며, yeast ${\alpha}-glucosidase$에 대한 억제 활성은 MeOH 추출물과 EA 분획물 그리고 BuOH 분획물의 $IC_{50}$이 각각 $137.36\;{\mu}g/ml$와 $171.52\;{\mu}g/ml$ 그리고 $115.14\;{\mu}g/ml$로 나타남으로써, 현재 혈당강하제로 사용되고 있는 acarbose와 1-deoxynorjirimycin보다 높은 억제 효과를 보였다. 또한 폴리올 대상 이상에 의한 당뇨병성 합병증 유발과 관련하여 Aldose reductase 억제활성을 조사한 결과, $50\;{\mu}g/ml$ 농도에서 EA 분획물과 MeOH 추출물이 각각 84.13%와 58.73%로 녹은 저해활성이 나타났다. 따라서 본 연구를 통하여 국내에 자생하는 사방오리나무 추출물로부터 부작용이 적고 혈당강하효과가 뛰어난 새로운 항당뇨 신물질을 탐색하여 산업화 하고자하며 이를 통하여 바이오 소재산업의 활성화와 바이오 식품 나아가 바이오 의약품 개발 등 다양한 측면에서 부가가치를 창출하고자 한다.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2222-2226
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• 2011

Amylase is a digestive enzyme that catalyses the starch into sugar. It has been reported that the green tea flavonoid (or polyphenols) (-)-epigallocatechin 3-gallate (EGCG) inhibits human salivary ${\alpha}$-amylase (HSA) and induced anti-nutritional effects. In this study, we performed docking study for seven EGCG-like flavonoids and HSA to understand the interaction mechanism of HSA and EGCG and suggest new possible flavonoid inhibitors of HSA. As a result, EGCG and (-)-epicatechin gallate (ECG) bind to HSA with complex hydrogen bonding interactions. These hydrogen bonding interactions are important for inhibitory activity of EGCG against HSA. We suggested that ECG can be a potent inhibitor of HSA. This study will be helpful to understand the mechanism of inhibition of HSA by EGCG and give insights to develop therapeutic strategies against diabetes.

• BMB Reports
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• 제37권6호
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• pp.642-647
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• 2004

The lysine residues of Bacillus licheniformis $\alpha$-amylase (BLA) were chemically modified using citraconic anhydride or succinic anhydride. Modification caused fundamental changes in the enzymes specificity, as indicated by a dramatic increase in maltosidase and a reduction in amylase activity. These changes in substrate specificity were found to coincide with a change in the cleavage pattern of the substrates and with a conversion of the native endo- form of the enzyme to a modified exo- form. Progressive increases in the productions of $\rho$-nitrophenol or glucose, when para nitrophenyl-maltoheptaoside or soluble starch, respectively, was used as substrate, were observed upon modification. The described changes were affected by the size of incorporated modified reagent: citraconic anhydride was more effective than succinic anhydride. Reasons for the observed changes are discussed and reasons for the effectivenesses of chemical modifications for tailoring enzyme specificities are suggested.

• Journal of Animal Science and Technology
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• 제54권2호
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• pp.133-139
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• 2012

Bacillus 균주가 생산하는 효소를 식품과 동물사료 첨가제로 이용하기 위해서 맥아로부터 단백질 분해능력과 전분 분해능력이 우수한 균주를 분리 동정하여 $Bacillus$ $amyloliquefaciens$ CNL-90으로 명명하였다. 분리된 $B.$ $amyloliquefaciens$ CNL-90이 생산하는 ${\alpha}$-amylase의 안정성은 pH는 7, 온도는 $40^{\circ}C$, protease의 경우는 pH가 7, 온도는 $50^{\circ}C$에서 안정했다. $B.$ $amyloliquefaciens$ CNL-90을 밀기울에 접종하여 고체 배양한 결과 ${\alpha}$-amylases의 효소활성은 6일 배양 후 290,000 unit/kg이었고, protease의 효소활성은 310,000 unit/kg으로 나타났다. 밀기울에 고체 배양한 생균수는 배양 6일 후에는 $2.2{\times}10^9$ CFU/g으로 높았다. 사료 요구율 개선은 $B.$ $amyloliquefaciens$ CNL-90 배양액 0.2% 첨가구가 대조구에 비해서 일당 증체량은 6.66% 높았고, 사료 요구율은 0.05% 효과가 있었다. 이러한 결과는 $B.$ $amyloliquefaciens$ CNL-90이 생산하는 단백질 분해효소와 전분 분해효소는 식품산업 및 가축사료 첨가제 산업에 응용할 수 있는 가능성을 확인하였다.

• BMB Reports
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• 제40권4호
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• pp.494-500
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• 2007

The endophytic bruchid pest Callosobruchus maculatus causes severe damage to storage cowpea seeds, leading to economical losses. For this reason the use of $\alpha$-amylase inhibitors to interfere with the pest digestion process has been an interesting alternative to control bruchids. With this aim, $\alpha$-amylase inhibitors from baru seeds (Dipteryx alata) were isolated by affinity chromatographic procedures, causing enhanced inhibition of C. maculatus and Anthonomus grandis $\alpha$-amylases. To attempt further purification, this fraction was applied onto a reversed-phase HPLC column, generating four peaks with remarkable inhibition toward C. maculatus $\alpha$-amylases. SDS-PAGE and MALDI-ToF analysis identified major proteins of approximately 5.0, 11.0, 20.0 and 55 kDa that showed $\alpha$-amylase inhibition. Results of in vivo bioassays using artificial seeds containing 1.0% (w/w) of baru crude extract revealed 40% cowpea weevil larvae mortality. These results provide evidence that several $\alpha$-amylase inhibitors classes, with biotechnological potential, can be isolated from a single plant species.

• Journal of the Korean Wood Science and Technology
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• 제42권2호
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• pp.149-156
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• 2014

Termites are wood pests that cause vast economic damage every year. They digest both cellulose and starch, but the enzymes for starch digestion have not been well characterized. We obtained complete amino acid sequence information on the KME1 ${\alpha}$-amylase from Reticulitermes speratus KMT1 through analysis of total mRNA sequences. The KME1 enzyme has two ${\alpha}$-amylase domains and is 68% identical to the ${\alpha}$-amylase from Blattellager manica, its closest relative in the GenBank database. Some unique features of its conserved region and its distant evolutionary relationship to other insect ${\alpha}$-amylases suggest that KME1 is a new type of ${\alpha}$-amylase.

• Preventive Nutrition and Food Science
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• 제19권1호
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• pp.5-9
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• 2014

This study was designed to investigate the inhibitory effects of Polyopes lancifolia extract (PLE) on ${\alpha}$-glucosidase activity, ${\alpha}$-amylase activitiy, and postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. The results of this study revealed a marked inhibitory effect of PLE on ${\alpha}$-glucosidase and ${\alpha}$-amylase activities. The $IC_{50}s$ of PLE against ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.20 mg/mL and 0.35 mg/mL, respectively. PLE was a more effective inhibitor of ${\alpha}$-glucosidase and ${\alpha}$-amylase activities than acarbose, the positive control. The postprandial blood glucose levels of STZ-induced diabetic mice were significantly lower in the PLE treated group than in the control group. Moreover, PLE administration was associated with a decreased area under the curve for the glucose response in diabetic mice. These results indicate that PLE may be a potent inhibitor of ${\alpha}$-glucosidase and ${\alpha}$-amylase activities and may suppress postprandial hyperglycemia.