• 한국식품위생안전성학회지
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• 제15권3호
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• pp.271-276
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• 2000

시중에서 시판되고 있는 발효비지로부터 총 58종의 균주를 분리하였으며, 그 중 starch 첨가 배지에서 투명환을 형성한 10종을 분리하였다. 이 10종의 균주를 정량적으로 amylase활성 측정을 하여 가장 큰 활성을 가진 2종의 균주를 재분리하여 공시 균주로 선정하였다 공시 균주를 동정한 결과 두 균주 모두 Bacillus sp로 동정되었으며, 각각 을 Bacillus sp. GM7330과 Bacillus sp. GM7312라고 명명하였다. 분리된 2종의 균주는 모두 5% 두부비지 용액에 glucose 3%와 yeast extract 0.15%를 첨가하여 초기 pH를 6.0으로 조정하여 30。C에서 72 hr 배양하였을 때 각각 488 units과 341 units_로 가장 큰 활성의 amylase를 생산하였다.

• Journal of Microbiology and Biotechnology
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• 제7권6호
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• pp.417-422
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• 1997

Recombinant Bacillus subtilis LKS88[pASA240] containing the amylase gene from Streptomyces albus KSM-35 was exploited in fed-batch cultivation for mass production of maltotetraose-producing amylase. The effects of dissolved oxygen, additional organic nutrients (peptone and yeast extract) and mixed carbon sources (glucose plus soluble starch) on amylase production were examined in fed-batch operations in an effort to determine the optimum conditions for a maximum amylase productivity. Under the optimum conditions, maximum amylase activity was about 4.2 times higher than that obtained in batch cultivations, indicating that mass production of maltotetraose-producing amylase could be accomplished in fed-batch cultivation of the recombinant B. subtilis strain.

• Applied Biological Chemistry
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• 제48권1호
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• pp.103-108
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• 2005

${\alpha}-Amylase$ 저해제는 소장에서 전분의 소화를 저해하여 포도당의 흡수를 지연시킴으로써 혈당 조절 목적으로 이용된다. 따라서 본 연구에서는 ${\alpha}-amylase$ 저해제를 탐색할 목적으로 국내 자생 목본류 약 1400여종의 70% ethanol 추출액을 대상으로 ${\alpha}-amylase$ 저해제 분포를 검색하였다. 수종의 목본류에서 ${\alpha}-amylase$ 저해제가 분포하고 있음이 확인되었으며, 그 중 활성이 비교적 높은 말채나무 기원의 저해제를 대상으로 연구를 진행하였다. 기원별 효소에 따른 저해 활성도를 살펴보면 salivary와 pancreatic ${\alpha}-amylase$, 미생물 기원의 ${\alpha}-glucosidase$에는 탁월한 저해 활성을 보인 반면 돼지 기원의 ${\alpha}-glucosidase$ 저해제에 대해서는 매우 낮은 저해 활성을 보였다. ${\alpha}-Amylase$와 ${\alpha}-glucosidase$의 kinetic을 분석하면 salivary와 pancreatic 두 효소에 모두 경쟁적 저해제로, 효모의 ${\alpha}-glucosidase$에는 비경쟁적과 반경쟁적의 혼합형 저해제로 나타났다. 또한 열과 산성에 대한 안정성을 확인한 결과 비교적 안정적인 것으로 나타났다. 본 추출물의 식이 섭취에 따른 혈당 강하 효과와 체중에 미치는 영향에서는 혈당과 체중 상승을 억제하는 효과가 확인되었고, mRNA수준에서 대퇴근 세포에 있어서 GLUT4의 발현이 증가됨을 확인하였다.

• 한국미생물·생명공학회지
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• 제45권4호
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• pp.277-283
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• 2017

전통 양조법을 활용하여 인공감미료를 첨가하지 않고 단맛이 보완된 전통주를 개발하기 위하여 고문헌에 기록된 주류 제조 시 쌀의 전처리 8가지 방법 즉, 죽, 범벅, 설기떡, 구멍떡, 물송편, 인절미, 개떡, 고두밥과 누룩에 존재하는 당화효소인 ${\alpha}$-, ${\beta}$-glucoamylase에 의한 당의 생성을 확인하였다. ${\alpha}$-amylase에 의해 생성된 maltose의 경우 반응 초기에는 개떡 > 설기떡 > 범벅 > 물송편 > 죽 > 인절미 > 구멍떡 > 고두밥의 순이었으나 48시간 후에는 인절미 > 범벅 = 고두밥 > 구멍떡 > 개떡 = 물송편 > 설기떡 > 죽의 순서로 생성양의 차이를 보였다. ${\beta}$-amylase 처리구의 maltose 생성은 ${\alpha}$-amylase 처리구와 유사한 결과를 보였으며, glucoamylase는 고두밥에서 약 10 mg/ml의 glucose가 생성되어 maltose의 생성과는 달리 8가지 전처리 방법 중 최대의 glucose 생성을 보였다. ${\alpha}$-amylase, ${\beta}$-amylase, glucoamylase 병행 처리한 경우는 ${\alpha}$-와 ${\beta}$-amylase에 의해 가수분해 되어 생긴 말단에 glucoamylase가 작용하여 glucose의 생성이 증가되었다. 술덧의 당 함량 변화를 보면 쌀의 전처리 방법에 따라 최종 잔당 함량에 차이를 보여 감미료를 첨가하지 않고 멥쌀로도 단맛이 보완된 술을 제조할 수 있는 배합비와 제조공정이 가능하게 되었다.

• 한국동물학회지
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• 제30권2호
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• pp.193-209
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• 1987

Patterns of amylase secretion in mouse pancreatic fragments were studied over a period of time after the tissue was stimulated by acetyicholine and MNNG. MNNG is known to activate guanylate cyclase and thus increase the cGMP concentration in the pancreatic acinar cell. These amylase secretion patterns were studied to investigate the role of cGMP in reaction cascade during secretion response of the tissues stimulated by acetyicholine. Cellular response of amylase secretion in the pancreas by acetyicholine was divided into two phases. During the first phase, zymogen granules which had existed in the cells were secreted by the action of $Ca^2$+ and calmodulin immediately after secretagogue administration, this being known as the initial response. When the tissue was stimulated by acetylcholine in a $Ca^2$+-deficient medium or one containing trifluoperazine as a calmodulin antagonist, this initial response was reduced. In the second phase, newly formed zymogen granules were secreted as sustained response after protein synthesis was triggered by secretagogue. This response was provoked by an activation of protein kinase C. When either cycloheximide as a protein synthesis inhibitor or dibucaine as a protein kinase C inhibitor were added to the incubation medium, this sustained response was remarkablely depressed in the pancreatic fragments stimulated with acetylcholine. In the pancreatic acinar cell, phosphatidylinositol turnover plays an important role in the secretion response and hexachlorocyclohexane inhibits this phosphatidylinositol turnover. The pancreatic tissue treated with the hexachlorocyclohexane exhibited inhibition on both initial and sustained responses of amylase secretion by acetylcholine. MNNG also accelerated amylase secretion from the tissue gradually along incubation time. The 22 minutes fraction of the pancratic secretion after administration of both acetylcholine and MNNG showed higher amylase activity than the neighboring fractions. Guanylate cyclase potentiated the sustained response. Even if it is experimented with an indirect method, guanylate cyclase was found responsible for activation of the sustained response of a step prior to the action of protein kinase C. As conclusion, it was considered that amylase secretion in mouse pancreatic fragments stimulated by acetylcholine is a three phasic response.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제2권2호
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• pp.159-168
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• 1998

Effect of plant growth regulators and end-product on the enzyme activities in cotyledons of Vigna angularis during germination was investigated by measuring the changes of $\alpha-amylase$ activities in attached and detached cotyledons applied growth regulators and sugars. The higher levels of $\alpha-amylase$ in detached cotyledons than those in cotyledons attached to the embryonic axis were due to both faster synthesis and slower degradation of the enzyme in the detached cotyledons than in the attached cotyledons. Levels of $\alpha-amylase$ activity were reduced by high concentrations of glucose and sucrose, and it is suggested that this effect was caused mostly by osmotic stress and partly by end-product repression. In detached cotyledons exogenously supplied $GA_3,$ IAA, kinetin, or their combinations has a small promotive effect on the developmental patterns of $\alpha-amylase$ activity ABA and uniconazole both prevented the synthesis of $\alpha-amylase$. Glucose inhibition of enzyme activity was partly reversed by the application of $GA_3,$ and CAMP. $GA_3,$ and cAMP seemed to act through a similar mechanism. The addition of inhibitors of protein and RNA synthesis largely prevented the increase of enzyme activity in the presence or absence of exogenous $GA_3,$. The pretreatment experiments with canavanine indicated that the earlier the time of addition was, the lower the amylase activity was.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.563-568
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• 2010

The Val289 residue in the $\alpha$-amylase of Bacillus amyloliquefaciens, which is equivalent to the Ala289 and Val286 residues in the $\alpha$-amylases of B. stearothermophilus and B. licheniformis, respectively, was studied by site-directed mutagenesis. This residue was substituted with 10 different amino acids by random substitution of the Val codon. In these mutant $\alpha$-amylases, Val289 was substituted with Ile, Tyr, Phe, Leu, Gly, Pro, Ser, Arg, Glu, and Asp. Compared with the wild-type $\alpha$-amylase, the mutant $\alpha$-amylase Val289Ile showed 20% more hydrolytic activity, whereas Val289Phe and Val289Leu showed 50% lesser activity. On the other hand, the mutant $\alpha$-amylases Val289Gly, Val289Tyr, Val289Ser, and Val289Pro showed less than 15% activity. The substitution of Val289 with Arg, Asp, or Glu resulted in complete loss of the $\alpha$-amylase activity. Interestingly, the mutant $\alpha$-amylase Val289Tyr had acquired a transglycosylation activity, which resulted in the change of product profile of the reaction, giving a longer oligosaccharide.

• 한국미생물·생명공학회지
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• 제27권2호
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• pp.129-135
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• 1999

EH-1 was highest at 9 days of incubation. This regrowth and enzymatic activity of Haloarcular sp. EH-1 was highest at 9 days of incubation. This amylase was purified by acetone fractionation, DEAG-Cellulose column chromatography, 1st Sephadex G-75 gel filtration, CM-Cellulose column chromatography and 2nd Sephadex G-75 gel filtration. The amylase was purified about 98.64 fold with a yield of 11.75%. The molecular weight of amylase was estimated to be about 43,000and 40,000 by gel filtration and SDS-polyacrylamide gel electrophoresis, respectively, suggesting that the enzyme was a monomer. Amylase had an optimal temperature of 4$0^{\circ}C$, and an optimum pH of 7.0, and the thermal stability was observed the above 50% at 10$0^{\circ}C$ after 1 hour, and the stable range of pH was 6.0 to 8.0. The enzymatic activity was increased in the presence of 10 mM 2-mercaptoethanol, slightly by 10 mM SnCl2.2H2O.FeCl2.4H2O.CuCl2.2H2O.HgCl2.6H2O and SDS. End products from soluble starch were glucose, maltose and maltotriose, and Km value for soluble starch was 2.5mg/ml.

• Journal of Microbiology and Biotechnology
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• 제18권4호
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• pp.695-703
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• 2008

A locally isolated thermophile, Geobacillus sp. SAB-40, producing thermostable extracellular amylase constitutively and an induced intracellular ${\beta}$-galactosidase was characterized and identified based on 16S rRNA sequencing. A phylogenetic analysis then revealed its closeness to Geobacillus stearothermophilus. To evaluate the effect of the culture conditions on the coproduction of both enzymes by G stearothermophilus SAB-40, a Plackett-Burman fractional factorial design was applied to determine the impact of twenty variables. Among the tested variables, $CaCI_2$, the incubation time, $MgSO_4{\cdot}7H_2O$, and tryptone were found to be the most significant for encouraging amylase production. Lactose was found to promote ${\beta}$-galactosidase production, whereas starch had a significantly negative effect on lactase production. Based on a statistical analysis, a preoptimized medium attained the maximum production of amylase and ${\beta}$-galactosidase at 23.29 U/ml/ min and 12,958 U/mg biomass, respectively, which was 3-and 2-fold higher than the yield of amylase and lactase obtained with the basal medium, respectively.

• 농업과학연구
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• 제15권2호
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• pp.153-163
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• 1988

Amylase 생산능(生産能)이 강(强)한 사상균(絲狀菌)을 얻기 위하여 온천부근(溫泉附近)의 공기(空氣), 토양(土壤), 퇴비(堆肥) 등(等)을 분리원(分離源)으로 하여 $45^{\circ}C$ 이상(以上)의 고온(高溫)에서 생육(生育)하는 200여(餘) 균주(菌株)를 분리(分離)하고 이 중(中)에서 amylase 생산능(生産能)이 우수(優秀)한 균주(菌株) L-11을 선정(選定)하여 형태학적(形態學的) 특성(特性)을 조사(調査)한 결과(結果) Mucor sp.로 동정(同定)되었다. 본(本) 실험(實驗)에서는 밀기울 고체배지(固體培地)를 사용(使用)하여 효소(酵素)의 생산조건(生産條件)과 작용조건(作用條件)을 검토(檢討)하였고, 더욱 효소(酵素)를 정제(精製)하고, 그 정제효소(精製酵素)의 성질(性質)들을 조사(調査)하여 다음과 같은 결과(結果)를 얻었다. 1. 선정균주(選定菌株)의 amylase 생산최적조건(生産最適條件)은 밀기울에 대(對)한 수분첨가율(水分添加量)이 80~100%이고, $50^{\circ}C$에서 2일간(日間) 배양(培養)하였을 때 가장 좋았다. 2. 선정균주(選定菌株) L-11의 조효소액(粗酵素液)을 DEAE-Sephadex A-50 column chromatography법(法)으로 정제(精製)하여 2종(種)의 amylase활성(活性) peak를 얻었으며 그 중(中) 1종(種)이 주효소(主醒素)(B peak enzyme) 이었다. 3. 선정균주(選定園妹)의 주요(主要) amylase의 정제효소(精製醒素)(B peak enzyme)는 전기영동적(電氣泳動的)으로 단일효소(單-醒素)라고 인정(認定)되었다. 4. 주요(主要) amylase의 정제효소(精製醒素)에 의(依)한 soluble starch의 분해반응(分解反應)에 있어서, 초기(初期)에는 소당류(小糖類)로서 주(主)로 maltose와 maltotriose를 생성(生成)하였으며, 반응(反應)이 진행(進行)됨에 따라 glucose와 maltose의 생성량(生成量)이 증가(增加)되었다. 5. 공식균주(供試菌株)는 주(主)로 ${\alpha}-amylase$를 강력(强力)하게 생산(生産)하며 glucoamylse는 거의 생산(生産)하지 않는 특이(特異)한 균주(菌株)라고 인정(認定)되었다. 6 주요(主要) amylase(B peak enzyme)인 정제(精製) ${\alpha}-amylase$의 작용(作俑) 최적(最適) pH는 4.0, 작용(作用) 최적(最適) 온도(溫度)는 $60{\sim}65^{\circ}C$, 안정(安定) pH 범위(範圍)는 4.0~9.0, 내열성(耐熱性)은 $70^{\circ}C$ 이상(以上)이었다.