• Journal of Microbiology and Biotechnology
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• 제20권2호
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• pp.383-390
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• 2010

A newly isolated active producer of raw-starch-digesting amyloytic enzymes, Rhizopus microsporus var. chinensis CICIM-CU F0088, was screened and identified by morphological characteristics and molecular phylogenetic analyses. This fungus was isolated from the soil of Chinese glue pudding mill, and produced high levels of amylolytic activity under solid-state fermentation with supplementation of starch and wheat bran. Results of thin-layer chromatography showed there are two kinds of amyloytic enzymes formed by this strain, including one $\alpha$-amylase and two glucoamylases. It was found in the electron microscope experiments that the two glucoamylases can digest raw corn starch and have an optimal temperature of $70^{\circ}C$. These results signified that amyloytic enzymes secreted by strain Rhizopus microsporus var. chinensis CICIM-CU F0088 were types of thermostable amyloytic enzymes and able to digest raw corn starch.

• The Korean Journal of Physiology and Pharmacology
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• 제15권6호
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• pp.383-388
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• 2011

Regulators of G-protein signaling (RGS) proteins are regulators of $Ca^{2+}$ signaling that accelerate the GTPase activity of the G-protein ${\alpha}$ -subunit. RGS1, RGS2, RGS4, and RGS16 are expressed in the pancreas, and RGS2 regulates G-protein coupled receptor (GPCR)-induced $Ca^{2+}$ oscillations. However, the role of RGS4 in $Ca^{2+}$ signaling in pancreatic acinar cells is unknown. In this study, we investigated the mechanism of GPCR-induced $Ca^{2+}$ signaling in pancreatic acinar cells derived from $RGS4^{-/-}$ mice. $RGS4^{-/-}$ acinar cells showed an enhanced stimulus intensity response to a muscarinic receptor agonist in pancreatic acinar cells. Moreover, deletion of RGS4 increased the frequency of $Ca^{2+}$ oscillations. $RGS4^{-/-}$ cells also showed increased expression of sarco/endoplasmic reticulum $Ca^{2+}$ ATPase type 2. However, there were no significant alterations, such as $Ca^{2+}$ signaling in treated high dose of agonist and its related amylase secretion activity, in acinar cells from $RGS4^{-/-}$ mice. These results indicate that RGS4 protein regulates $Ca^{2+}$ signaling in mouse pancreatic acinar cells.

• 한국식품영양학회지
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• 제13권3호
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• pp.213-220
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• 2000

본 연구는 찹쌀가루액에 효소처리 및 미생물 접종을 시킴으로써 유과의 제조시 수침과정을 거치지 않고도 유과를 만들수 있는 새로운 방법을 개발하기 위하여 시도되었다. 찹쌀 수침액에 분포된 미샐울은 Bacillus sp와 Lastobacillus spp.로 나타났다. 찹쌀 수침액에 인위적으로 상기 미생물을 배양하였을 대 유과를 제조하기 위한 최적 조건은 3$0^{\circ}C$에서 18시간 이었다. 이때 찹쌀수침액의 PH는 배양시간이 증가함에 따라 증가하였다. 이 찹쌀 수침액에서는 수침시간이 증가함에 따라 $\alpha$-amylase 활성이 증가하여 효소처리된 시료액의 효소 활성화 유사한 경향을 나타내었다. 유과의 팽화도는 효소처리시킨 혼합 접종처리 군을 제외한 모든 처리군에서 28일간 수침한것과 유사하게 나타났다. 경도와 peak수는 모든 처리순에서 28일간 수침시킨 대조군에 비해 유의적으로 더 낮게 나타났다.(P<0.05). 미세구조에서 기공수는 효소처리시킨 단독 접종군이 다른 모든 처리군에 비해 더 많은 기공수를 지니고 있었고 기공의 둘레 및 면적도 유의 적으로 낮은 수치를 나타내었다. .(P<0.05). 따라서, 수침공정을 대폭 단축할 수 있었으며, 향후 미생물 접종을 고려한 효소처리 조건을 정밀 분석한다면 수침공정이 없어도 유과의 품질특성을 나타내는것이 가능할 것으로 보인다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권4호
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• pp.500-508
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• 2011

Forty-four Gansu Alpine Fine-wool lambs were used to study changes in the activities of three gastric and five pancreatic enzymes under grazing conditions between 0 and 56 days of age. The lambs were slaughtered on days 0, 3, 7, 14, 21, 28, 42 and 56, the abomasal contents, mucosa and pancreas were immediately removed and placed into liquid nitrogen and enzyme activities were determined. Gastric enzyme (chymosin, pepsin and pregastrc esterase) activities were relatively high at birth, especially chymosin, but decreased quickly between day 0 and 21. The activity of pepsin changed insignificantly with increasing age. There was no significant change in the pancreatic enzyme activities (trypsin, chymotrypsin, ${\alpha}$-amylase, lipase and lactase). The activity of trypsin was relatively higher than that of the other pancreatic enzymes, and lactase activity was low. These ontogenic patterns might be under the control of many gut regulatory peptides, the plasma concentrations of which changed simultaneously. Some gastric and pancreatic enzymes were correlated with plasma concentrations of these gut regulatory peptides.

• 한국생활과학회지
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• 제14권6호
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• pp.1037-1046
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• 2005

Using three consecutive years' harvested rices and their starches isolated from rice flours by alkaline method, it was found that no significant aging effect on rice flour and starch was observed based on following results. Proximate data of flours or starches showed in similarity, except high level of crude fat in rice flour and rice starch harvested in 2002. In SEM, the surface of aged rice flour had slightly layered shape due to possible abrasion during storage, and that of aged starch showed more smooth and less rigid polygonal shape. X-ray diffraction patterns of flours and starches were all A type, and crystallinity of rice starch harvested in 2000 had the smallest. From tristimulus colorimetry (Hunterlab Color), total color difference ($\Delta$E) calculated from L, a, and b gave less color difference with the darkest in 2002 harvested one among flours and the lightest in 2001 one among starches. WBCs of both 2002 rice flour and starch were the lowest among samples studied. At 80$^{\circ}C$, swelling power and solubility of rice starches harvested in 2000, 2001 and 2002 were 14.35, 9.75; 14.04, 9.6; and 12.49, 8.82, respectively. The highest peak viscosities measured by RVA were shown both in 2001 rice flour and in its starch. Starch and milled rice flour harvested in 2000 had higher hydrolytic $\alpha$-amylase, compared to other flour and starch samples.

• Nutrition Research and Practice
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• 제6권5호
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• pp.389-395
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• 2012

The study elucidated carbohydrase inhibition, anti-cancerous, free radical scavenging properties and also investigated the DNA and protein protection abilities of methanolic root extract of Rumex crispus (RERC). For this purpose, pulverized roots of Rumex crispus was extracted in methanol (80% and absolute conc.) for 3 hrs for $60^{\circ}C$ and filtered and evaporated with vacuum rotary evaporator. RERC showed high phenolic content ($211{\mu}g$/GAE equivalent) and strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ($IC_{50}$ = 42.86 (absolute methanol) and $36.91{\mu}g/mL$ (80% methanolic extract)) and reduced power ability. Furthermore, RERC exhibited significant protective ability in $H_2O_2/Fe^{3+}$/ascorbic acid-induced protein or DNA damage and percentage inhibition of the HT-29 cell growth rate following 80% methanolic RERC exposure at $400{\mu}g/mL$ was observed to be highest ($10.2%{\pm}1.03$). Moreover, methanolic RERC inhibited ${\alpha}$-glucosidase and amylase effectively and significantly (P < 0.05). Conclusively, RERC could be considered as potent carbohydrase inhibitor, anti-cancerous and anti-oxidant.

• Journal of Microbiology
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• 제43권3호
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• pp.244-250
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• 2005

The effect of cytochrome $c_{550}$ encoded by cccA in Bacillus subtilis during the event of sporulation was investigated. The sporulation of cccA-overexpressing mutant was significantly accelerated, while disruptant strain showed delayed sporulation in spite of the same growth rate. Activity of sporulation stage-0-specific enzyme, extracellular $\alpha-amylase$ of mutant strains was similar to that of the control strain, but cccA-overexpressing mutant exhibited higher activity of stage-II-specific alkaline phosphatase and stage-III-specific glucose dehydrogenase when compared to deletion mutant and control strain. Northern blot analysis also revealed that cccA-overexpressing mutant showed high level of spo0A transcripts, while the disruptant rarely expressed spo0A. These results suggested that although cytochrome $c_{550}$ is dispensable for growth and sporulation, expression of cccA may play an important role for initiation of sporulation through regulation of spo0A expression.

• 한국응용과학기술학회지
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• 제1권1호
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• pp.23-31
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• 1984

In order to investigate the acute toxicity of autoxidized methyl linoleate(AOML) on the activity of serum enzymes in the mouse, we administered once 0.45ml of AOML to ICR strain mouse by using stomach tube. The following results were obtained: The total lactic dehydrogenase(LDH) activities in the serum of AOML group were generally increased than those of normal group. According to electrophoresis, the activities of LDH, were increased while those of LDH, were decreased. The activities of glutamic oxaloacetic transaminase(GOT), glutamic-pyruvic transaminase(GPT) and ${\alpha}-amylase$ in the serum of AOML group were increased more than those of normal group. The activities of alkaline phosphatase in the serum of AOML group were increased but those of isozyme were not confirmed in the normal and AOML group. In the serum protein of AOML group, albumin was increased, on the other hand ${\gamma}-globulin$ was decreased. At the peripheral blood slide smear, lymphocytes were significantly decreased but neutrophils were increased and the morphological change of erythrocytes was observed. From these results we conclude that the AOML fed to mouse influences on the activity of various serum enzymes and blood cells in the mouse.

• 한국미생물·생명공학회지
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• 제24권2호
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• pp.247-253
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• 1996

Changes in microorganisms, enzyme activities and major components of two types of Doenjang prepared with spring Meju and autumn Meju and Kochujang were investigated during 4 months of fermentation. The viable cell counts of aerobic bacteria in Doenjang and Kochujang were increased up to 60 days of fermentation, but viable cell counts of anaerobic bacteria did not show remarkable changes during fermentation. Viable cell count of yeast showed a rapid increase up to 15 days of fermentation in Doenjang and 60 days in Kochujang. It was found that $\alpha$-amylase activity of autumn Meju Doenjang and glucoamylase activity of Kochujang were higher than the other. Acidic and neutral protease showed the highest activity during 15-30 days of fermentation. The pH of Doenjang was increased up to pH 7.0 until 60 days of fermentation, but pH of Kochujang gradually decreased during fermentation. Moisture content of spring Meju Doenjang and Kochujang decreased to 40% during ferme- ntation and reducing sugar content of Kochujang increased up to 15 days of fermentation, but decreased after that.

• Journal of Microbiology and Biotechnology
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• 제3권4호
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• pp.298-302
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• 1993

Pullulan was produced from starch hydrolysate with Aureobasidium pullulans SH8646. We could measure the correct amount of pullulan produced without the interference of starch from the culture supernatant by using a bacterial $\alpha$-amylase treatment and ethanol: acetone (1:1) precipitation. When 5% acid-hydrolyzed starch was used as a carbon source, the dry cell weights obtained were similar irrespective of DE values of starch hydrolysates. The dry cell weights of those on the starch hydrolysate media prepared with 0.1 N HC1 treatment, were slightly higher (9.5~10.5 g/l) than those on the starch hydrolysate media prepared with 1.0 N HCl (8.5~9.5 g/l). And among the starch hydrolysates showing DE values lower than 50, maximum pullulan production of 15 g/l was obtained at DE 30~40 starch hydrolysate but those showing DE values higher than 50, the pullulan production was increased with the increase of the DE value of starch hydrolysates. From the media containing 5%, 10%, and 15% starch hydrolysate (DE 25, 45, and 75), about 20~34% pullulan yield was obtained and the maximum pullulan yield of 34% (17g/l) was obtained from 5% DE 75 starch hydrolysate. The pullulan yields from starch hydrolysate media were much lower than those from glucose, maltose, maltotriose, and sucrose media.