• 한국식품영양과학회지
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• 제27권3호
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• pp.367-375
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• 1998

The physicochemical properties of the $\alpha$-amylase inhibitors from black bean and naked barley is Korea were investigated. Preincubation time for maximum inhibition was 30min and no activity change was seen after that time. Optimum pH of the $\alpha$-amylase inhibitors from the black bean and naked barley was pH 7.0 and the inhibitory activities were stable in the range of pH 6.0~8.0 in both phosphate and Tris-HCI buffer solutions. Both inhibitors maintained more than 50% of activity after incubation for 17 min at 7$0^{\circ}C$. The inhibitors from the black bean and naked barley maintained more than 50% of activities after treatment for 40 min and 30 min with pepsin, and 30 min and 50 min with trypsin, respectively. Both inhibitors functioned via a noncompetitive mechanism and were active against porcine pancreatic and human salivary $\alpha$-amylases. The activities of both inhibitors were linear for the ionic stength ranging from 0 to 0.9. The addition of 70 mM maltose to the reaction mixture caused a maximum increase in the relative activities of both inhibitors, but it did not affect the dissociation of the EI complex. The activities of both inhibitors were significantly enhanced by adding 1mM of K+ or Mg2+.

• 한국미생물·생명공학회지
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• 제13권3호
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• pp.223-232
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• 1985

한국의 토양에서 분리한 균 중 bacterial $\alpha$-amylase에 저해효과가 있는 균주를 분리하여 DMC-47 균주라 명명하였고, 이 균주는 Streptomyces 속의 균임을 확인하였다. 이 균주를 옥수수 전분 배지에서 진탕 배양한 결과 4일후에 최대 저해 효과를 나타내었다. 이 균주가 생성한 저해물질은 bacterial $\alpha$-amylase, pancreatic $\alpha$-amylase, salivary $\alpha$-amylase, glucoamylase에 저해효과를 보였고, $\beta$-amylase 에는 저해효과가 없었다.

• 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.

• 한국식품저장유통학회지
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• 제1권2호
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• pp.117-124
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• 1994

To investigate characterization of the ${\alpha}$-amylase inhibitors from cereals and legumes produced in Korea, inhibitory activities against ${\alpha}$-amylase with the inhibitor from barley(Hordeum vulgare), wheat(Triticum aestivun), black bean(Glycine max), bean(Cajanus cajon) and pea(Pisum sativum) were measured. Among the samples tested, inhibitors from naked barley and black bean(sabong) which showed the highest inhibitor activities of cereals and legumes, respectively, were characterized according to treatment condition. The results obtained were summarized as follows. During the germination of naked barley and black bean, ${\alpha}$-amylase activities were gradually increased but inhibitory activities against ${\alpha}$-amylases were decreased. Both activities were gradually decreased when naked barley and black bean were stored. More than 50% of activities of the inhibitors from naked barley and black bean were remained at 100$^{\circ}C$ for 15 min and 20 min, respectively, indicating that the inhibitor from black bean was more stable to heat than that of barley.

• 약학회지
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• 제33권3호
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• pp.175-182
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• 1989

To find ${\alpha}-amylase$ inhibitors produced by microorganisms from soil, a strain which had a strong inhibitory activity against bacterial ${\alpha}-amylase$ was isolated from the soil sample collected in Korea. The morphological and physiological characteristics of this strain on several media and its utilization of carbon sources showed that it was one of Streptomyces species according to the International Streptomyces Project method. The amylase inhibitor of this strain was purified by active carbon adsorption, silicagel column chromatography, SP-Sephadex C-25 column chromatography, adsorption on Amberlite XAD-2. The inhibitor was oligosaccharide which was composed of glucose. The inhibitor had inhibitory activity against other amylase such as salivary ${\alpha}-amylase$, pancreatic ${\alpha}-amylase$, fungal ${\alpha}-amylase$ and gluco-amylase.

• Archives of Pharmacal Research
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• 제8권2호
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• pp.67-75
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• 1985

To find emylase inhibitors produced by microorganisms from soil, a strain which had a strong inhibitory activity against bacteria .alpha.-amylase was isolated from the soil smaple collected in Seoul. The morphological and physiological characteristics of this strain on several media and its utilization of carbon sources showed that it was one of Streptomyces specties according to the international Streptomyces Project method. The amylase inhibitor of this strain was purified by means of acetone precipitation, adsorption on Amberlite XAD-2, and column chromatography on Amberlite CG-50 and SP-Sephadex C-25. The inhibitor was stable at the pH range of 1-10 and at 100.deg.C for half an hour, and had inhibitory activities against other amylases such as salivary .alpha.-amylase, pancreatic .alpha.-amylase, fungal .alpha.-amylase and glucoamylase. The kinetic studies of the inhibitor showed that its inhibitory effect on starch hydrolysis by .alpha.-amylase was non-competitive.

• 약학회지
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• 제32권5호
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• pp.304-307
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• 1988

394 strains of soil microorganism were isolated from the Korean soil samples. The isolated strains were shake-cultured in oat-meal medium. The filtrates of the cultures were screened for the production of ${\alpha}-amylase$ inhibitors. Five strains were identified to produce ${\alpha}-amylase$ inhibitors. And these strains were identified as Actinomycetes.

• Advances in Traditional Medicine
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• 제4권4호
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• pp.227-234
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• 2004

An ${\alpha}-Amylase$ was purified to apparent homogeneity from germinating soybean seeds (Glycine max). Enzyme showed high specificity for starch. ${\alpha}-Amylase$ from soybean has optimum pH at 7.6 in the pH range 4.0-10.6. At this pH, the $K_m$ of starch was 2.63 mg/ml and the $V_{max}$ was equal to 52.6 mg/ml/min protein. Optimum temperature of the enzyme was found to be $55^{\circ}C,\;Q_{10}$ equal to 1.85 and energy of activation equal to 12 kcal/mol. Additives like, EDTA reduced the activity of ${\alpha}-amylase$ whereas PMSF enhanced the activity. ${\alpha}-Amylase$ was inhibited by several heavy metal ions.

• Food Science and Biotechnology
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• 제17권2호
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• pp.302-307
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• 2008

Novel amylase inhibitors were synthesized via transglycosylation by Thermotoga maritima glucosidase (TMG). TMG hydrolyzes acarbose, acarviosine-glucose, and maltooligosaccharide by releasing $^{14}C$-labeled glucose from the reducing end of each molecule. When TMG was incubated with acarviosine-glucose (the donor) and glucose (the acceptor), two major transfer products, compounds 1 and 2, were formed via transglycosylation. The structures of the transfer products were determined using thin-layer chromatography (TLC), high-performance ion chromatography (HPIC), and $^{13}C$ nuclear magnetic resonance (NMR) spectroscopy. The results indicate that acarviosine was transferred to glucose at either C-6, to give a $\alpha-(1{\rightarrow}6$) glycosidic linkage, or at C-3, to produce an $\alpha-(1{\rightarrow}3$) glycosidic linkage. The transfer products showed a mixed-type inhibition against porcine pancreatic $\alpha$-amylase; therefore, they may be useful not only as inhibitors but also as acarbose transition-state analogs to study the mechanism of amylase inhibition.

• 한국식품과학회지
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• 제33권1호
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• pp.117-121
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• 2001

Phaseolus vulgaris을 분쇄한 후 ethanol 70% 및 80% 포화도에서 침전을 행하고 그 침전물을 다시 ammonium sulfate로 재침전한 후, DEAE-Sephadex ion exchange chromatography 및 Sephadex G-100 gel의 chromatography를 행하여 활성을 보인 fraction I-1-f와 I-2-f를 분획하였다. 그 결과 분리된 I-1-f의 총 단백질량은 12.0 mg/L, 총 활성은 2784 unit/L, 비활성은 232 unit/mg이였으며 정제도는 15.0배 증가하였고 수율은 5.56%이였다. 또한 I-2-f의 총 단백질량은 14.0 mg/L, 총 활성은 3210 units/L, 비활성은 229.28 units/mg protein이였으며, 정제도는 14.8배 증가하였으며 수율은 6.4%이였다. 또한 polyacrylamide gel electrophoresis를 행한 결과 단백질 band가 각각 하나로 확인되어 각각 단일 성분으로 판단되었다. 정제 ${\alpha}-amylase$ 저해제 I-1-f와 I-2-f의 분자량은 gel filtration과 SDS-polyacrylamide gel electrophoresis를 행한 결과 50,000과 45,000이었다. 또한 구성성분의 함량을 측정한 결과 각각 $17.6{\sim}17%$의 당과 $79{\sim}80%$의 단백질로 구성되어 있으며 당은 glucose : xylose : mannose : N-acetylglucosamine의 함량이 5 : 3 : 50 : 42의 구성성분을 갖고 있음을 확인하였다.