• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.644-651
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• 2009

This study was conducted to investigate the effects of steeping periods and temperatures of waxy rice on the microflora and enzyme activities of steeping water and waxy rice, as well as on the microscopic structures of waxy rice during the preparation of gangjung. When the steeping water was 15 and $35^{\circ}C$, yeast and lactic acid bacteria were the major microflora after 1 day. After 11 days, Lactobacillus spp. were the major bacteria, while Bacillus spp. were the primary microflora after 21 days. At $25^{\circ}C$ the primary species were Bacillus spp., Leuconostoc spp., and Bacillus spp. after 1, 11 and 21 days, respectively. The $\alpha$-amylase activity of steeping water increased proportionally with the increase of temperature and period, while the protease activity tended to increase for 11 days, but decreased at 21 days. The enzyme activities of the steeped waxy rice, especially the $\alpha$-amylase activity, decreased with higher steeping temperature, while the $\beta$-amylase and glucoamylase activity remained constant for up to 21 days. Observation using scanning electron microscopy indicated that intracellular cleavage of steeped waxy rice endosperm resulted in a rough surface morphology due to the exposure of polygonal starch granules. Tiny pinholes on the surface of waxy rice starch granules were also observed after steeping for 11 days.

• Journal of Microbiology and Biotechnology
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• v.2 no.2
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• pp.85-91
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• 1992

The intestinal microflora of humans is an extraordinarily complex mixture of microorganisms, the majority of which are anaerobic microorganisms. The distribution of amylolytic microorganisms in the human large intestinal tract was investigated in various individuals of differing ages using anaerobic culture techniques. A large percentage of the amylolytic microorganisms present belonged to the Genus Bifidobacteria. The number of Bifidobacteria increased significantly at two years of age. Adults and children above 2 years old carried about $0.8{\times}10^9-2.0{\times}10^{10}$ colony forming units (CFU/gram) of amylolytic Bifidobacteria. Among these amylolytic Bifidobacteria, Int-57 was chosen for further studies. Between 65% and 85% of the amylase produced was secreted and the remaining amylase was bound to the cell wall facing the outside. Amylase production could be induced by starch in a stable form. When cells were grown on maltose or glucose, amylase production was much lower than on starch and amylase activity disappeared after 24 hours growth on these media. Partially purified enzymes showed optimum activity at a temperature of $50^{\circ}C$ and at an optimum pH of 5.5, respectively. Heat treatment at $70^{\circ}C$ for 30 minutes almost completely inactivated amylase. The hydrolysis products of starch were mainly maltose and maltotriose. Soluble starch, amylose, amylopectin, and $\gamma$-cyclodextrin($\gamma$-CD) were easily hydrolyzed. The rate of hydrolysis of $\alpha$-CD and $\beta$-CD was slower than that of $\gamma$-CD. Carboxymethyl cellulose, $\beta$-1, 3-glucan and inulin were not hydrolyzed.

• Food Science and Preservation
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• v.23 no.5
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• pp.738-745
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• 2016

We evaluated the distribution pattern of tannin in 164 sorghum breeding lines and the inhibition rates of amylase, protease, and lipase in sorghum lines with different tannin concentrations. Tannin was existed in the testa of sorghum grain. The tannin content in whole grain of Nampungchal sorghum was 11.54 mg/g, and that in grain (milling rate 73%) and bran fractions was 4.57 mg/g and 28.71 mg/g, respectively. The inhibition rate of ${\alpha}$-amylase, ${\alpha}$-glucosidase, and ${\beta}$-glucosidase in sorghum lines with tannin was higher than that in sorghum lines without tannin. The inhibition rate of ${\alpha}$-glucosidase was greater than 97% in sorghum lines with tannin. The inhibition rate of protease ranged from 20% to 70% in the sorghum lines, showing no discernable trends in tannin content. Lipase inhibition was either very low or not observed and did not seem to correlate with tannin concentration.

• The Korean Journal of Food And Nutrition
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• v.7 no.4
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• pp.259-266
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• 1994

The hyperthermophilic archaebacterium Thermococcus profundus Isolated from a deep-sea hydrothermal vent system, produced several amylolytic enzymes such as extracellular amylase and pullulanase, intracellular a-1,4-91ucosidase in respone to the presence of complex carbohydrates In the growth medium. This strain showed high activities on 0.5% maltose than on complex carbohydrates One of the amylases was partially purified by ammonium sulfate precipitation, DEAE-Toyopearl chromatography. The amylase exhibited maximal activity at pH 5.5 and 80$^{\circ}C$, and was stable in the range of pH 5.5 to 9.5 and up to 80$^{\circ}C$ for 30 min. The enzyme activity was no dependence on Ca2+ and not inhibited by detergents. The amylase hydrolyzed soluble starch, amylose, amylopectin and glycogen to produce maltose and maltotriose with trace amounts of glucose, but not pullulan and ${\alpha}$-, ${\beta}$-, ${\gamma}$-cyclodextrin. Malto-oligosaccharides ranging from maltotetraose to maltoheptaose were hydrolyzed in an endo fashion.

• KSBB Journal
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• v.23 no.5
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• pp.419-424
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• 2008

In this study, we examined the anti-diabetic activity in vitro by the crude extracts of Tetragonia tetragonioides which has been known to superior plants for the traditional prevention and treatment of stomach-related diseases. $\alpha$-Amylase and $\alpha$-glucosidase, the principal enzymes involved in the metabolism of carbohydrates, and aldose reductase, the key enzyme of the polyol pathway, have been shown to play the important roles in the complications associated with diabetes. A hexane (HX) fraction of T. tetragonioides were shown to inhibit more than 50% of salivary and pancreatin $\alpha$-amylase activity at concentration of 2.882 mg/mL and 2.043 mg/mL, respectively. In addition, the HX and ethylacetate (EA) fraction showed the highest inhibitory activity on yeast $\alpha$-glucosidase at values of $IC_{50}$ of 0.723 mg/mL and 1.356 mg/mL respectively. The HX, dichloromethane (DCM) and EA fraction showed more higher inhibitory activity on yeast $\alpha$-glucosidase than commercial agent such as 1-deoxynorjirimycin and acarbose. Also, the aldose reductase from human muscle cell had been inhibited strongly by the DCM fraction and HX fraction at 51.95% and 47.22% at a concentration of 1 mg/mL, respectively. Our study, for the first time, revealed the anti-diabetic potential of T. tetragonioides and this study could be used to develop medicinal preparations or nutraceutical and functional foods for diabetes and related symptoms.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1306-1318
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• 2009

The filamentous ascomycete Sclerotinia sclerotiorum is well known for its ability to produce a large variety of hydrolytic enzymes. Two $\alpha$-amylases ScAmy54 and ScAmy43 predicted to play an important role in starch degradation were showed to produce specific oligosaccharides essentially maltotriose that have a considerable commercial interest. Primary structure of the two enzymes was established by N-terminal sequencing, MALDI-TOF masse spectrometry and cDNA cloning. The two proteins have the same N-terminal catalytic domain and ScAmy43 derived from ScAmy54 by truncation of 96 amino acids at the carboxyl-terminal region. Data of genomic analysis suggested that the two enzymes originated from the same $\alpha$-amylase gene and that truncation of ScAmy54 to ScAmy43 occurred probably during S. sclerotiorum cultivation. The structural gene of Scamy54 consisted of 9 exons and 8 introns, containing a single 1,500-bp open reading frame encoding 499 amino acids including a signal peptide of 21 residues. ScAmy54 exhibited high amino acid homology with other liquefying fungal $\alpha$-amylases essentially in the four conserved regions and in the putative catalytic triad. A 3D structure model of ScAmy54 and ScAmy43 was built using the 3-D structure of 2guy from A. niger as template. ScAmy54 is composed by three domains A, B, and C, including the well-known $(\beta/\alpha)_8$ barrel motif in domain A, have a typical structure of $\alpha$-amylase family, whereas ScAmy43 contained only tow domains A and B is the first fungal $\alpha$-amylase described until now with the smallest catalytic domain.

• Journal of Plant Biology
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• v.17 no.4
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• pp.143-156
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• 1974

The purpose of this experiment was to study one side of germination physiology based on that protein profiles and protease relating to protein metabolism, that peroxidase, catalase, $\alpha$-amylase, $\beta$-amylase, and malate dehydrogenase involved in the carbohydrate metabolism of seed germination. All these experiments were divided into the two groups with and without acetone treatment, and were carried out. The protein bands of each germinating stage between the groups treated with and without acetone showed certain basic pattern in polyacrylamide gel disc electrophoresis. However, there was a little difference in the number of protein band, optical density, and migration velocity between two groups. The isozyme bands of peroxidase, and catalase between two groups in polyacrylamide gel disc electrophoresis did not show the numeral difference, but the optical density of certain germinating stage treated with acetone was higher than the group untreated with it and it showed their enzyme activity. The $\alpha$-amylase and $\beta$-amylase activities which involved in starch metabolism of seed germination were higher in the treated group than the other. On one hand, the protease activity of hydrolase occurred in the seeds for germination was also higher, more or less in the treated group than in the other. The isozyme band pattern of malate dehydrogenase in TCA cycle of energy metabolism pathway was very different between two groups growing for 72 hours with and without acetone treatment in cellulose acetate electrophoresis. It indicated that two isozyme bands of malate dehydrogenase was high. Consequently these experimental results mentioned above indicated that acetone treatment before sowing had an effect on dissolving certain complexed lipid substance involved in the seed coats, the activity of carbohydrate hydrolase increased with water absorption which was most comfortable in its germination, dissolved glycerin and fatty acid became certain energy source, and they stimulated the acceleration of respiration metabolism.

• Applied Biological Chemistry
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• v.35 no.4
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• pp.232-236
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• 1992

In order to manufacture of soy paste, Changes of chemical composition and enzyme activity of soybean by different processing method were investigated. The results are summarized as follows: Changes of chemical compositions were; Raw(A) and soaked(B) soybeans contain about 2% of more crude fat than roasted(C) and steamed(D) soybeans, roasted and steamed soybeans contain $1.16{\sim}1.74%$ of more protein than those of raw and soaked soybeans, and Raw and roasted soybeans contain $0.11{\sim}0.41%$ of more crude fiber than those of soaked and steamed soybeans. ${\alpha}-amylase$, ${\beta}-amylase$, protease, lipase activity of raw and soaked soybeans were $2{\sim}5$ folds higher than those of roasted and steamed soybeans. Trypsin inhibitor activity of raw, soaked, roasted and steamed soybeans was indicated 56.7%, 42.9%, 32.9% and 20.8% in the order, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.2
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• pp.1-6
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• 1982

The constituents of sugar, enzyme activity and number of pollens in standard honey (gathered from my own honey comb.) and commercial ones collected from local markets) were determined to know the difference between above two kinds of honey. The results obtained were as follows. 1. The constitution of saccharides in commercial honey was higher at 1% than the standard one. The average content showed 45% of fructose,41% of glucose, 3% of dextrin and 2% of sucrose. 2. Pollen contained in honey were mainly composed of oval and globe shape. The nunlber of pollen contained in standard honey was five times more than that in commercial ones .3. ${\alpha}-amylase$, ${\beta}-amylase$ and protease activity of standard honey were greated 5,2,2 times respectively comparing with that of commercial one, and acid protease activity with each sample was higher than the neutral.

• Microbiology and Biotechnology Letters
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• v.7 no.4
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• pp.217-223
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• 1979

Six strains of mold which had high saccharifying and acid-productive ability were isolated from wild sources. The strain M-80 among them and Aspergillus kawachii, which was generally used as rice makkulli koji were used for this studies. The results obtained were summarized as follows. 1) $\alpha$-amylase activities of the strain M-80 and Asp, kawachii showed similarly as about 140W. V., while $\beta$-amylase activity of M-80 was 54 A. U. and Asp. kawachii was 40 A. U. 2) Acid protease activity of M-80 was higher then Asp. kawachii but alkaline protease activity was lower Asp. kawachii respectively. 3) The contents of total acid, ethanol and fusel oil in makkulli brewing with M-80 were higher those of Asp. kawachii and methanol contents of the tested two strains were about 33mg/％. 4) Fifteen kinds of free amino acid were detected from makkulli brewing of two strains, and free amino acid contents of M-80 were 10％ higher than those of Asp. kawachii.