• 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.

• 미생물학회지
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• 제34권3호
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• pp.137-143
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• 1998

수계에서 전분 가수분해 효소의 transglycosylation 반응을 이용하여 배당체(glycoside)를 합성하였다. Glycosyl donor인 가용성전분과 glycosyl acceptor인 benzylalcohol을 기질로 하여 ${\alpha}$-amylase에 의해 합성되는 배당체는 glucose의 1번 OH기에 benzylalcohol이 ${\alpha}$형태로 결합한 benzylalcohol-${\alpha}$-glucoside(BG)와 benzylalcohol-${\alpha}$-maltoside(BM)이었다. pH 5.0의 반응에서는 주로 BG가, pH 8.0의 반응에서는 BM만이 합성되는 특이한 반응양상을 보였다. Transglycosylation 반응의 최적조건은 가용성전분 50 mg/ml, benzylalcohol 50 mg/ml, 온도 $30-35^{\circ}C$, 효소량 10 unit/ml이었으며, 합성된 BG는 ${\alpha}$-glucodisase에 의해 glucose와 benzylalcohol로 가수분해되었으며 BM의 경우는 pH 5.0에서는 glucose와 BG로 가수분해되었으나 pH 8.0이상에서는 전혀 분해되지 않았다. BM과 구조적으로 유사한 maltotriose는 pH 5.0에서 glucose와 maltose로 가수분해 되었으나 transglycosylation반응은 거의 일어나지 않았으며 pH 8.0에서는 가수분해도 transglycosylation반응도 일어나지 않았다.

• 한국미생물·생명공학회지
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• 제19권2호
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• pp.122-127
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• 1991

A bacterial strain NO. 32 which produced thermostable ${\alpha}$-amylase was isolated from soil and identified to genus of Bacillus. To enhance ${\alpha}$-amylase productivity, a successive mutation of Bacillus sp. No. 32 was attempted with treatment of N-methyl-N'-nitro-N-nitrosoguanidine (NTG). The resulting mutant, Bacillus sp. No. 32H417, which is risistant to refampicin and deficient in spore formation, produced about 90-fold high level of ${\alpha}$-amylase when compared with parental strain. The properties of the enzyme for thermostability were investigated. The optimal temperature and pH for enzyme reaction were 95$^{\circ}C$ and pH6.5, respectively, in the presence of 0.3mM $Ca^{2+}$ as an effective stabilizer.

• 한국미생물·생명공학회지
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• 제21권6호
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• pp.534-541
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• 1993

The relationship between Schwanniomyces occidentalis CBS 2863 (formerly castellii) and CBS 1153 (formerly alluvius), and their variety persoonii was examined at alpha-amylase gene level. Using Sch. occidentalis alpha-amylase gene as probe, Sch. occidentalis alpha-amylase gene homologues were obtained from Sch. occidentalis CBS 1153 and Sch. occidentalis var. persoonii. The restriction analysis of these homologues showed that the restriction enzyme sites between Sch. occidentalis CBS 2863 and CBS 1153 was identical but different between these strains and Sch. occidentalis var. persoonii.

• 한국식품영양과학회지
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• 제24권4호
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• pp.556-562
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• 1995

The $\alpha$-amylase inhibitor from naked barley was purified by DEAE-cellulose, Concanavalin-A sepharose and superose 6 column chromatography, and confirmed by capillary electrophoresis. The purified $\alpha$-amylase inhibitor showed a single band of 29KD in molecular weight when estimated by the SDS-PAGE. Its purity was increased by 12-fold as compared to its crude extract, and its specific activity was found to be 336.7units/mg. The major amino acids of the $\alpha$-amylase inhibitor from naked barley was appeared to be glutamic acid, asparitic acid and arginine. The inhibitor from naked barley was glycoproteins and carbohydrate content of inhibitor was 1.0%.

• 미생물학회지
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• 제31권2호
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• pp.175-178
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• 1993

Alkaline .alpha.-amylase expressed in the transformant, Baciollus subtills MB809, containing alkaline amylase gene cloned from alkalophilic Bacillus sp. AL-8, was purified through for step separation processes. The purified alkaline .alpha.-amylase had molecular weight of app[roximately 59, 000 daltons on SDS-PAGE and Sephaex G-100 gel filtration. Amino acid sequence of terminal portion of the enzyme was analyzed with pure amylase eluted form the SDS-PAGE gel. N-terminal amino acid sequence of .alpha.-amylase was determined by the Edman degradation method and resulted in $NH_{2}$-ser-thr-ala-pro-ser-(ile)-lys-ala-gly-thr-(ile)-leu. For C-terminal amino acid sequencing, purified .alpha.-amylase was digested with carboxypuptidase A and B, and reverse-phase HPLC gradient elution system resulted in -thr-trp-pro-lys-COOH.

• Journal of Applied Biological Chemistry
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• 제58권1호
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• pp.1-3
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• 2015

This study investigated the inhibitory activities of 2-hydroxyquinoline and its analogs against ${\alpha}$-glucosidase and ${\alpha}$-amylase. Based on the $IC_{50}$ values of 2-hydroxyquinoline analogs tested against ${\alpha}$-glucosidase and ${\alpha}$-amylase, 2-hydroxyquinoline had potent inhibitory activity (64.4 and $130.5{\mu}g/mL$, respectively), while 2-methyl-8-hydroxyquinoline showed weakly inhibitory activity (90.7 and $215.4{\mu}g/mL$, respectively). 2-Methylquinoline demonstrated no activity against ${\alpha}$-glucosidase and ${\alpha}$-amylase. In conclusion, 2-hydroxyquinoline analogs, with the existence of a methyl group and hydroxyl on quinoline, can be useful as a new diabetes treatment.

• Journal of Applied Biological Chemistry
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• 제58권1호
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• pp.5-8
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• 2015

This study was to isolate an active component of the chloroform fraction from the methanol extract of Ruta chalepensis leaves and to measure inhibitory effects against ${\alpha}$-glucosidase or ${\alpha}$-amylase. The inhibitory compound of R. chalepensis leaves was isolated using chromatographic methods and identified as quinoline. Quinoline and its structurally related derivatives were tested for their inhibitory activities by evaluating the $IC_{50}$ values against ${\alpha}$-amylase or ${\alpha}$-glucosidase and were compared with that of acarbose. Based on the $IC_{50}$ values, quinazoline exhibited the greatest inhibitory activity ($20.5{\mu}g/mL$), followed by acarbose ($66.5{\mu}g/mL$), and quinoline ($80.3{\mu}g/mL$) against ${\alpha}$-glucosidase. In case of ${\alpha}$-amylase, quinazoline had potent inhibitory activity, followed by quinoline ($179.5{\mu}g/mL$) and acarbose ($180.6{\mu}g/mL$). These results indicate that R. chalepensis extract, quinoline, and quinazoline could be useful for inhibiting ${\alpha}$-glucosidase or ${\alpha}$-amylase.

• KSBB Journal
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• 제14권6호
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• pp.707-712
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• 1999

Dextransucrse와 ${\alpha}$-amylase의 혼합효소반응 통하여 새로운 구조의 올리고당을 생산하였고, 그 특성을 조사하였다. 기질인 설탕과 녹말의 농도를 10%(w/v), 5%(w/v)로 하였을 때 dextransucrase와 ${\alpha}$-amylase의 활성비가 100U대 1000U일 경우 올리고당의 종류와 생산수율이 66.4%로 가장 높았다. 녹말의 분해산물이 dextransucrase의 수용체 반응을 활성화시켜 dextransucrase 활성을 증가시켰다. 혼합효소의 활성이 증가할수록 올리고당보다는 다당을 생산하였다. 5%(w/v)의 녹말을 1시간동안 반응시켜 수용체로 이용될 수 있는 산물의 양을 증가시킨 후 설탕의 농도가 10%(w/v)가 되도록 반응시킨 방법이 녹말과 설탕을 반응초기부터 모두 반응시킨 방법보다 올리고당 생산수율이 12% 더 증가하였다. 새로운 구조의 올리고당은 pH 3에서는 10.6, pH 4에서는 7.8%의 분해를 보였다. 새로운 구조의 올리고당은 pH 6과 140$^{\circ}C$ 고온에서 89.3%까지 안정하였다.

• 한국식품조리과학회지
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• 제15권5호
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• pp.533-538
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• 1999

떡의 노화를 지연하여 상품성을 개량할 수 있는 방법을 개발하고자, $\alpha$-amylase를 첨가하여 백설기를 제조하였다. $\alpha$-amylase는 전분을 가수 분해하여 환원당의 함량을 증가시킴으로써 떡의 수분활성도를 낮추고, 백색도를 감소시키며 이러한 결과 전분의 노화가 지연되는 것을 X-ray 회절 양상의 변화를 통하여 확인하였다. 또한 떡의 관능검사 결과 $\alpha$-amylase를 첨가한 떡은 상온과 냉동 저장 모든 경우에서 더욱 촉촉하고 부드러운 조직감을 나타내어 전분의 노화가 억제됨을 관찰할 수 있었다. 그러나 떡의 수분 함량은 효소를 첨가한 것과 하지 않은 것간에 유의적인 차이를 나타내지 않았으므로 이러한 촉촉한 느낌은 자유수 형태의 수분 함량보다는 환원당의 함량이 증가되어 나타나는 현상임을 확인 할 수 있었다.