• 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.

• 약학회지
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• 제35권1호
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• pp.30-37
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• 1991

Streptomyces actuosus DMCJ-49 and Streptomyces minoensis DMCJ-144 produce the .alpha.-amylase inhibitor. Inerspecific protoplast fusion technique was used to increase the productivity of .alpha.-amylase inhibitor. Four auxotrophic mutants were obtained respectively from two strains by N-methyl-N'-nitor-N-nitrosoguanidine(3mg/ml) treatment. The optimum conditions for the protoplast formation of Streptomyces actuosus DMCJ-49 ade was as follows; 1.2% w/v of glycine, 3mg/ml of lysozyme, and 30 min of lysozyme treatment followed by 36 hr. incubation in the protop-last formation medium. In case of DMCJ-144-his those were 1.2%w/v, 3 mg/ml, 30 minutes and 60 hours, respectively. Regeneration was accomplished with hypertonic soft agar medium that contained 0.4M sucrose, 20mM CaCl$_2$, 50 mM MgCl$_2$ and low levels of phosphate. Fusion of protoplasts carrying different auxotrophic markers was achieved by treatment with polyethylene glycol. The optimum concentration of polyethylene glycol 1450 for the production of recombinants was 40%w/v. When the protoplasts was treated with 40% polyethylene glycol for 30 minutes, the frequency of recombinants was 6.5$\times$$10^{-3}$ and the $\alpha$-amylase inhibition activity of $ade^-his^-$ No. 4, which is the fusant with the most improved activity increased from 33 to 125 I.U./ml.

• 한국축산식품학회지
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• 제30권5호
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• pp.795-803
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• 2010

A DF01 strain that inhibits tyramine-producing Lactobacillus curvatus KFRI 166 was isolated from Dongchimi, a traditional Korean fermented vegetable, and identified as Lactobacillus brevis by biochemical analysis and reverse transcriptase sequencing of 16S rRNA. The antimicrobial compound produced by L. brevis DF01 was secreted at a maximum level of 640 AU/mL in late exponential phase in MRS broth, and its activity remained constant during stationary phase. The activity of bacteriocin DF01 was totally inactivated by $\alpha$-chymotrypsin, pronase E, proteinase K, trypsin, and $\alpha$-amylase, but not by catalase, which indicates the compound was glycoprotein in nature. The activity was not affected by pH changes ranging from 2 to 12 or heat treatment (60, 80, and $100^{\circ}C$ for 30 min), but was reduced after autoclaving. Bacteriocin DF01 had bacteriolytic activity and a molecular weight of approximately 8.2 kDa, as shown by tricine-SDS-PAGE analysis. Therefore, bacteriocin DF01 can be used in the manufacture of fermented meat products due to its inhibition of tyramine-producing L. curvatus and non-inhibition of L. sake, which is used as a starter culture for meat fermentation.

• 한국식품저장유통학회지
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• 제23권5호
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• pp.738-745
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• 2016

본 연구는 수수 계통들의 탄닌 함량별 소화효소 저해율을 조사하여 향후 수수 품종육성과 수수의 이용성 향상을 위하여 실시하였다. 남풍찰수수의 탄닌의 분포를 조사한 결과, 과피와 배유사이의 종피층에 탄닌이 분포함을 알 수 있었다. 도정을 하지 않은 조곡에서 탄닌 함량은 11.54 mg/g이었고, 73% 도정한 종실과 겨에서 각각 4.57 mg/g과 28.71 mg/g으로 가장 높게 나타났다가 65% 도정한 종실과 겨에서 2.06 mg/g과 26.38 mg/g으로 줄었다. 수수 추출물 탄닌 함량별로 15계통을 대상으로 소화효소 반응을 조사한 결과, 탄닌이 함유된 계통들에서 탄닌이 없는 계통들에 비해 당질가수분해 효소인 ${\alpha}$-amylase, ${\alpha}$-glucosidase, ${\beta}$-glucosidase 저해율이 높게 나타났다. 특히 ${\alpha}$-glucosidase의 저해율은 모든 탄닌 계통에서 97% 이상으로 다른 소화효소들에 비해 매우 특이적으로 높은 저해율을 보였다. Protease의 저해율은 탄닌 계통들에서 non-탄닌 계통들에 비해 전반적으로 높게 나타났다. Lipase 저해율은 20% 이하로 저해가 일어나지 않거나 매우 낮아 수수 계통들간의 lipase 저해율의 유의성이 없었다.

• 한국식품저장유통학회지
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• 제18권6호
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• pp.923-929
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• 2011

본 연구는 당뇨처방을 근거로 구성된 생약재 복합물의 항당뇨 효능을 조사하기 위하여 복합물의 인슐린성 물질을 탐색하고 ${\alpha}$-amylase 및 ${\alpha}$-glucosidase 저해활성을 평가하였다. 3T3-L1 세포에 복합 생약재 추출물을 $10{\mu}g/mL$의 농도로 처리하였을 때 지방세포로의 분화능은 151.7%로 인슐린의 작용을 향상시키는 것으로 확인되었다. 혈당저하제로서 생약재 복합 추출물의 ${\alpha}$-amylase에 대한 저해활성은 생약재 복합 추출물 10.0, 1.0 및 0.1 mg/mL의 농도에서 각각 38.4, 31.5 및 16.6%이었으며, ${\alpha}$-glucosidase에 대한 생약재 복합 추출물의 저해활성은 같은 농도에서 각각 81.3, 35.8 및 26.7%였다. 열수 추출물과 80% ethanol 추출물의 각종 용매 분획물에 대한 ${\alpha}$-glucosidase 저해활성은 다양한 용매 분획물 가운데 ethyl acetate층에서 66.9%와 55.1%로 가장 높은 활성을 나타내었다.

• 대한약리학회지
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• 제17권2호
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• pp.31-36
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• 1981

Heavy metals which are present as trace elements in human body have been known to modify various enzymatic reaction. These metals can be essential or non-essential. Zinc, copper and calcium are essential in maintaining some biological processes, whereas non-essential metals such as cadmium, lead and mercury produce accumulatve toxic effect. Cadmium accumulated in pancreas can cause toxicity and damage of pancreatic cells, thereby influencing CHO metabolism. Lead compounds are known to produce toxic effects on the kidney, digestive system and brain fellowed by inhibition of activity of ${\rho}-aminolevulinic$ acid and biosynthesis of hemoproteins and cytochrome. Evidence has been accumulated that zinc not only acts as a cofactor in enzyme reaction but also prevents toxic effect induced by heavy metal such as copper and cadmium. To demonstrate the effect of heavy metals on pancreatic secretion, part of uncinate pancreas was taken and incubated in Krebs-Ringer bicarbonate buffer with heavy metals used. Additional treatment with CCK-OP was performed when needed. After incubation during different period of time, medium was analyzed for amylase activity using Bernfeld's method. The present study was attempted in order to elucidate the effect of several kinds of heavy metal on exocrine pancreatic secretion in vitro. The results obtained are as follows: 1) CCK-OP stimulated significantly amylase release from pancreatic fragments in vitro. 2) CCK-OP response of amylase release from pancreatic fragments was inhibited by treatmant with cadmium, especially high doses of cadmium. 3) CCK-OP response of amylase release from pancreatic fragments was inhibited when pretreated with $10^{-4}M$ copper chloride. 4) Lead chloride at the concentration of $10^{-3}M\;and\;10^{4}M$ stimulated the basal amylase release in vitro but CCK-OP response did not augment by lead chloride. 5) Zine chloride did not affect amylase release from pancreatic fragment in vitro. From the results mentioned above, it is suggested that CCK-OP response was inhibited it the amylase release from pancreatic fragments pretreated with cadmium and copper chloride.

• The Korean Journal of Ecology
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• 제17권2호
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• pp.171-183
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• 1994

Soil condition, total number of bacteria, soil amylase activity and microbial biomass $(CO_2-C)$ were measured at soil of different forest types. And the difference of the allelopathic effect was determined between fresh leaf extract of Quercus acutissima and Pinus rigida to the bacteria isolated from soil of different forest types. 1. Total number of bacteria in Carpinus laxiflora forest soil was 4~7 times larger than that in pinus desiflora forest soil. 2. Soil amylase activity was positively correlated with total number of soil bacteria and soil organic matter content. The amylase activity at F layer was 4~5 times larger than that at H layer, and that at H layer was 2~4 times larger than that at A layer. 3. Seasonal changes of microbial biomass showed a peak in summer, and vertical distribution of microbial biomass decreased with increasing soil depth. The microbial biomass in Pinus densiflora forest soil was larger than that in Quercus serrata forest soil. 4. Fresh leaf extract of Pinus rigida and Quercus acutissima showed an acceleration or inhibition effect on the growth of soil bacteria, and that of !. acutissima inhibited larger number of soil bacterial strains than that of P. rigida. 4.2% and 25% of soil bacterial strains isolated from soil of P. rigida and Q. acutissima forests were inhibited by fresh leaf extract of P. rigida and Q. acutissima, respectively.

• 한국약용작물학회지
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• 제15권2호
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• pp.128-131
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• 2007

This study was carried out to investigate inhibitory effect of extracts from Artemisia capillaris Thumb. on maltase, sucrase, ${\alpha}-amylase$, nonspecific ${\alpha}-glucosidase$, and postprandial hyperglycemia. Methanol extract and organic solvent (n-hexane, ethyl acetate, butanol, aqueous) fractions from the medicinal herb were determined for the inhibitory activities against maltase, sucrase and ${\alpha}-amylase$. The methanol extract from A. capillaris strongly inhibited maltase (57%) and ${\alpha}-glucosidase$ (72%) at the concentration of 100 ${\mu}g/m{\ell}$. Among the four fractions (n-hexane, ethyl acetate, butanol, aqueous) examined, the butanol fraction from A. capillaris showed potent inhibitory effects on maltase (73%), sucrase (33%), and ${\alpha}-amylase$ (75%) at the concentration of 100 ${\mu}g/m{\ell}$. The butanol fraction from Artemisia capillaris also exhibited significant reductions (20%) of blood glucose elevation in mice loaded with maltose. These results suggest that the extract from Artemisia capillaris can be used as a new nutraceutical for inhibition on postprandial hyperglycemia

• 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+.

• 생약학회지
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• 제42권1호
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• pp.61-67
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• 2011

In this study, we evaluated the bioactivities of methanol extract and its solvent fractions of Sonchus asper (L.) Hill. The EtOAc fraction of S. asper exhibited more strong antioxidant activity than other extracts as evidenced by the strongest 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity with a $EC_{50}$ value at $33.55\;{\mu}g/mL$ and reducing power, the total polyphenol (180.71 mg GAE/g) and flavonoid contents (145.86 mg QE/g) of S. asper extract were higher than other extracts. The EtOAc fraction of the S. asper also showed 47.38% mushroom tyrosinase inhibition activity, 56.22% ${\alpha}$-glucosidase inhibition and 46.58% ${\alpha}$-amylase inhibition ratio at 1 mg/mL. Both methylene chloride and EtOAc fractions of methanol extract of S. asper effectively reduced of the 86.34% and 62.03% angiotensin I converting enzyme (ACE) activity at 2 mg/mL, respectively. These findings suggest that the EtOAc fraction of the S. asper could be a potential antioxidant in food additive, medicinal, and industry product.