• Journal of Microbiology and Biotechnology
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• 제29권5호
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• pp.765-775
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• 2019

A new ${\alpha}$-amylase-encoding gene (amySL3) of glycoside hydrolase (GH) family 13 was identified in soda lake isolate Alkalibacterium sp. SL3. The deduced AmySL3 shares high identities (82-98%) with putative ${\alpha}$-amylases from the genus Alkalibacterium, but has low identities (<53%) with functionally characterized counterparts. amySL3 was successfully expressed in Escherichia coli, and the recombinant enzyme (rAmySL3) was purified to electrophoretic homogeneity. The optimal temperature and pH of the activity of the purified rAmySL3 were determined to be $45^{\circ}C$ and pH 7.5, respectively. rAmySL3 was found to be extremely halophilic, showing maximal enzyme activity at a nearly saturated concentration of NaCl. Its thermostability was greatly enhanced in the presence of 4 M NaCl, and it was highly stable in 5 M NaCl. Moreover, the enzyme did not require calcium ions for activity, and was strongly resistant to a range of surfactants and hydrophobic organic solvents. The major hydrolysis products of rAmySL3 from soluble starch were maltobiose and maltotriose. The high ratio of acidic amino acids and highly negative electrostatic potential surface might account for the halophilic nature of AmySL3. The extremely halophilic, calcium-independent, and surfactant-resistant properties make AmySL3 a promising candidate enzyme for both basic research and industrial applications.

• Journal of Animal Science and Technology
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• 제59권7호
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• pp.16.1-16.6
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• 2017

Background: This study was performed to investigate the impact of exogenous ghrelin on the pancreatic ${\alpha}$-amylase outputs and responses of pancreatic proteins to ghrelin that may relate to pancreatic exocrine. Methods: Sprague-Dawley male rats (9 weeks old, $300{\pm}10g$) were injected with ghrelin via intraperitoneal (i.p.) infusion at dosage of 0, 0.1, 1.0 and $10.0{\mu}g/kg$ body weight (BW), respectively. The plasma ghrelin and cholecystokinin (CCK) level were determined using enzyme immunoassay kit; the mRNA expression of ghrelin receptor ($GHSR-1{\alpha}$) and growth hormone (GH) receptor were assessed by reverse transcription PCR; the expressions of pancreatic ${\alpha}$-amylase activity, extracellular-signal-regulated kinases (ERK), phosphorylated extracellular-signal-regulated kinases (pERK) and c-Jun N-terminal kinase (JNK) were evaluated by western blotting; moreover the responses of pancreatic proteins to ghrelin were analyzed using the two-dimensional gel electrophoresis system. Results: The exogenous ghrelin (1.0 and $10.0{\mu}g/kg\;BW$) elevated the level of plasma ghrelin (p < 0.05), and suppressed the expression of pancreatic ${\alpha}$-amylase at a dose of $10.0{\mu}g/kg\;BW$ (p < 0.05). No difference in the level of plasma CCK was observed, even though rats were exposed to any dose of exogenous ghrelin. In addition, a combination of western blot and proteomic analysis revealed exogenous ghrelin ($10.0{\mu}g/kg\;BW$) induced increasing the JNK and ERK expressions (p < 0.05) and four proteins such as Destrin, Anionic trypsin-1, Trypsinogen, and especially eukaryotic translation initiation factor 3 in rat pancreas. Conclusions: Taken together, exogenous ghrelin by i.p. infusion plays a role in the pancreatic exocrine secretion via mitogen-activated protein kinase signaling pathway.

• 동의생리병리학회지
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• 제33권2호
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• pp.109-115
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• 2019

Aster Yomena (AY) has been used in traditional medicine to treat diseases such as obesity, hyperlipidemia, atherosclerosis, diabetes and osteoarthritis. However, protective effect of AY on acute pancreatitis (AP) has not been reported. The present study examined the anti-inflammatory effects of an ethanol extract of AY on cerulein-induced AP. AP was induced in mice by intraperitoneally injecting cerulein ($50{\mu}g/kg$) hourly for 6 times. 70% ethanol extract of AY (0.1, 0.2, and 0.5 g/kg) was orally administered for 1 week before acute pancreatitis induction. The mouse was killed at 6 hours after the final cerulein injection. The pancreas and lung were rapidly removed for histological examination and myeloperoxidase (MPO) assay. Blood samples were taken to determine serum amylase and lipase activity. In addition real-time reverse transcription-polymerase chain reaction (RT-PCR) was also performed to investigate mRNA expression of proinflammatory cytokines such as $TNF-{\alpha}$. $IL-1{\beta}$, and IL-6. Administration of AY significantly ameliorated pancreatic weight to body weight ratio, histological damages and MPO activity during AP. In addition, AY inhibited the serum amylase and lipase activity during AP. Also, mRNA expression of $TNF-{\alpha}$, $IL-1{\beta}$ and IL-6 were inhibited by AY against AP. Our results revealed that pre-treatment of AY reduces the severity of cerulein-induced AP. Therefore, AY may have a protective effect drug against AP.

• 한국미생물·생명공학회지
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• 제22권1호
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• pp.7-12
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• 1994

One bacterial strain, that had made the largest inhibition zone at the antagonism assay and also that lost the inhibition activity by the protease treatment, was isolated from raw milk. That strain was identified as Streptococcus salivarius subsp. thermophilus. The specific growht rate of this strain was maximum at 45$\circ $C. However, at this temperature the strain produced no bacteriocin. The bacteriocin activity was quite stable even at high temperature. Moreover, the activity of the vacteriocin was sensitive to proteases. but not to $\alpha $-amylase, DNase I, or RNase.

• Mycobiology
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• 제29권3호
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• pp.173-175
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• 2001

The fruit body of Ramaria botrytis DGUM 29001 was used to determine enzyme activities of fruit body. The specific activity of laccase was the highest(6.5 unit/mg$\cdot$protein) and that of $\alpha$-amylase and xylanase was relatively high. However, little or no enzyme activity of $\beta$-glucosidase, CMCase, exo-$\beta$-1,4-glucanase, chitinase, lipase and protease was found.

• 한국식품영양과학회지
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• 제38권8호
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• pp.989-995
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• 2009

쓴 메밀의 용매에 따른 추출수율은 물 추출물이 39.0%, 70% 에탄올 추출물이 7.0%, 100% 메탄올 추출물이 6.6%로 물 추출 시 수율이 가장 높았으며 효소처리에 의해 추출수율이 크게 향상되어 $\alpha$-amylase 처리 시 95.1%로 가장 높아 가용성 고형분의 함량이 증가하였다. DPPH radical 소거 활성 측정 결과 메탄올과 에탄올 추출물의 $RC_{50}$ 값이 각각 34.0 $\mu g$/mL, 40.5 $\mu g$/mL로 높은 활성을 지닌 것으로 나타났으며, 효소 처리에 의해 활성이 증가되어 $\beta$-glucosidase 처리구와 cellulase 처리구의 $RC_{50}$ 값이 각각 32.3 $\mu g$/mL, 33.0 $\mu g$/mL 으로 나타났다. ABTS radical 소거 활성 측정 결과 100 $\mu g$/mL의 농도에서 메탄올, 70% 에탄올 추출물이 30%가 넘는 활성을 보였으며, 물 추출물의 소거 활성은 낮았고 효소 처리에 의해 활성이 증가하여 $\alpha$-amylase 처리구를 제외한 모든 효소 처리구의 활성이 대조구인 70% 에탄올 추출구보다 활성이 우수하였다. Hydrogen peroxide 소거 활성 측정 결과 $RC_{50}$ 값이 메탄올 추출물이 32.3 $\mu g$/mL, 70% 에탄올 추출물이 35.9 $\mu g$/mL로 높은 소거 활성을 가지는 것으로 나타났으며 효소처리에 의해 소거 활성이 증가하는 것으로 나타났으나 효소 종류에 따른 유의적인 차이는 없었다. 쓴 메밀 추출물의 $\alpha$-glucosidase 저해 활성은 에탄올 추출물의 $RC_{50}$ 값이 59.9 $\mu g$/mL로 가장 높은 저해 활성을 보였으며 $\alpha$-amylase 처리구가 저해 활성이 가장 높았다. HPLC 분석 결과 메탄올 추출물의 rutin 함량이 4,400.3 mg/100 g, quercetin 함량이 71.9 mg/100 g으로 가장 많은 양의 rutin과 quercetin을 함유하고 있는 것으로 나타났으며, 에탄올 추출물 또한 rutin과 quercetin의 함량이 각각 3,459.8 mg/100 g과 56.9 mg/100 g으로 메탄올 추출물과 비슷한 양을 함유하고 있었으며 물 추출물은 상대적으로 적은 양을 함유하고 있었다. 가수분해 효소 처리 시 $\beta$-glucanase 처리구의 rutin의 함량이 5,057.4 mg/100 g으로 가장 높았다. 결과적으로 쓴 메밀의 메탄올과 에탄올 추출물은 항산화 활성이 뛰어나며 항 당뇨에도 효과가 있으며, 효소 처리에 의해 쓴 메밀에서의 수용성 고형분 함량이 크게 증가하며 항산화 활성과 $\alpha$-glucosidase 저해 활성이 증가하는 것으로 나타났다.

• 생약학회지
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• 제9권4호
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• pp.173-175
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• 1978

The repeated administration of the cherry bark extract and its some fractions suppressed profoundly the antibody production in mice which were immunized with bacterial ${\alpha}-amylase$.

• 생명과학회지
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• 제23권5호
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• pp.616-621
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• 2013

진범은 열독을 제거하고 발한을 유도하여 몸의 수분을 조절하는 효과를 가져 한방에서 사용되어 왔으며, 항염증 활성과 장기의 면연체계를 조절하는 효과가 있는 것으로 알려졌다. 본 연구에서는 진범 추출물의 항노화와 항당뇨 활성을 조사하였다. 물과 에탄올을 이용하여 진범을 추출하고 그 추출물이 가지는 DPPH, ABTS 라디칼 소거활성, PF 및 TBARs와 같은 항산화 활성과 ${\alpha}$-amylase와 ${\alpha}$-glucosidase 저해활성을 측정하였다. 진범 물과 에탄올 추출물의 농도 $100{\mu}g/ml$, $50{\mu}g/ml$ 처리군부터 50% 이상의 DPPH 라디칼 소거활성이 나타났고, ABTS 라디칼 소거활성은 에탄올 추출물의 농도 $1,000{\mu}g/ml$ 처리군에서 $99.8{\pm}0.1$%로 가장 높게 나타났다. 베타카로텐리놀레이트 모델 시스템을 이용한 항산화 활성 측정결과 $500{\mu}g/ml$ 이상의 농도로 첨가하였을 때 물 추출물에서 1.27 PF, 1.33 PF값을, 에탄올 추출물에서는 1.40 PF, 1.49 PF로 나타났으며, 에탄올 추출물의 농도 $1,000{\mu}g/ml$ 처리군에서 $0.16{\pm}0.03{\mu}M$로 가장 낮은 TBARs값을 나타내었다. 물 추출물의 농도 $1,000{\mu}g/ml$ 처리군와 에탄올 추출물의 100~$1,000{\mu}g/ml$ 처리군에서 90% 이상의 ${\alpha}$-amylase 저해 활성과 60% 이상의 ${\alpha}$-glucosidase 저해 활성을 나타내었다. 이러한 결과를 종합하여 볼 때 진범의 생리활성을 이용하여 항노화 화장품 원료와 항산화 및 항당뇨 예방물질 소재로의 활용이 가능할 것으로 판단된다.

• 환경위생공학
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• 제24권1호
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• pp.40-46
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• 2009

The enzyme expressed from strain L-49 was 2.01 times higher than that of original strain. Strain L-49 can grow on culture plate with $50{\mu}g/mL$ ampicillin. The synthesis of $\alpha$-amylase was greatly suppressed when strain L-49 was grown on monosaccharide such as glucose and polysaccharide at the same time cell concentration was low. Amylase production was enhanced when the bacterium was grown on starch and dextrin. Among different nitrogen sources tried, yeast extract was found to be the best followed by panpeptone, peptone, meat extract, bean meal, and corn steep liquor. The average rate of enzyme production was enhanced for 3~4 times in fermentation time from 24h to 44h. The sugar uptake rate has also increased. Low oxygen supply rate enhanced the rate of strain propagation but depressed the enzyme production. Hence it is benefit to obtain high enzyme activity that agitation speed maintained not lower than 400r/min and aeration rate maintained greater than 1:1vvm.

• Journal of Korean Biological Nursing Science
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• 제25권4호
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• pp.306-315
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• 2023

Purpose: This study aimed to evaluate the rest-activity circadian rhythm (RAR) using data obtained from wearable actigraph devices in hospitalized older adults with mild cognitive impairment (MCI), and to investigate its relationship with salivary alpha amylase (sAA). Methods: This secondary data analysis used data from the Hospitalized Older Adults' Cognition and Physical Activity Study. Actigraph data for 3-4 days were analyzed for RAR. RAR indices such as interdaily stability (IS), intradaily variability (IV), activity level during the most active 10-hour period and during the most least active 5-hour period, and relative amplitude (RA) were calculated. Data on sAA collected in the morning and general characteristics, including body mass index (BMI), were analyzed. Results: Data from 92 hospitalized older adults with MCI were analyzed. The IS, IV, RA were 0.23, 0.73, 0.88, respectively. The average level of sAA was 77.02 U/mL, and a higher level of sAA was significantly associated with better IS and RA in the regression analysis, while age, BMI, and cognitive level were not. BMI showed positive correlations with IS and RA. Conclusion: RAR in the hospitalized older adults with MCI was attenuated, showing especially low IS, which implies they failed to maintain regular and repetitive 24-hour RAR. Increased sAA and BMI were associated with robust RAR. Nurses need to pay attention to maintain robust RAR in hospitalized older adults with MCI, and strategies should be developed to improve their RAR.