• Korean Journal of Microbiology
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• v.5 no.2
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• pp.43-54
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• 1967

The characteristics of enzymic sources and its effective uses concerned with brewing of Yack-Tack Joo which is traditional and popular liquors for all Korean have been studied. Results obtained are as follows; 1)Kock Ja (enrich of fungi and yeast produced in Korean brewery) is found to be weak in its liquifying(600U.) and saccharifying activity(1300U.), so that it is useful to conbine two factors effectively for better brewing. 2) The additional ratio of Kok Ja per materials is seems proper at line of 20 percent for better fermentation and the enzymic preparations inoculated of microorganisms in wheat bran is seems proper at 25 percent line. 3) Adding the enzymic preperation in which the strain Rhyzopus had been inoculated to the experimental mash at 5 percent per material, the rate of fermentation was revealed highest degree than those of else. 4) It is not proper to add a single Bun Kok in fermentation, as it produce much acid in mash during brewing. 5) However, the enzymic preparation composed of Asp usami and Rhyzopus sp. produced less acid in brewing. 6) The increasing of temparature in enzymic samples, temparatures of the mixtured Kuk(Kok Ja and enzymic preparation) are higher than those of single addition at the first stage in pre-fermentation, but there are no differences at the late stage of post-fermentation. 7) Amount of amino acids in the plot of enzymic prepation are found much more than those of single use at late stage of post-fermentation. In the plot of single use of Kock Ja, the amount was the most than else, the proteinase activity is strongest more than else. 8) In the brewing of Korean Tack-Yack-Joo, it is desirable less amount of acidity, more amount of amino acid, stronger liquifaction of starch and vigorous saccharification. Thren it was found that the application of two prepations(Kock Ja and Bun kok) is most effective to get moderate quality in Tack-Yack-Joo brewing.

• Microbiology and Biotechnology Letters
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• v.14 no.5
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• pp.359-363
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• 1986

S. diastaticus hydrolysised $\alpha$-1.4 linkage of the starch and was known fermenting yeast strain, but poorly hydrolized $\alpha$-1.6 linkage of the starch. To improve the starch fermentation ability of yeast, we tried that protoplast fusion between S. diastaticus and C. tropicalis and finally two starins of fusant (FPDC42, FPDC43) were obtained. C. tropicalis well hydrolysis both $\alpha$-1.4 and $\alpha$-1.6 linkanges in the starch. The protoplast of parental auxotrophic cells were fused in the presence of 10mM CaCl$_2$ and 35% of polyethylene glycol (M. W. 4,000). The fusion frequency was 10$^{-5}$ to 10$^{-6}$. Properties of the fusants(genetic stability, assimilation of carbon sources, random spore formation, copper resistance, NaCl tolerance, DNA content, cell size and growth rate) were investigated.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.2
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• pp.112-127
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• 1997

The purpose of this study is to get optimum operating factors of Upflow Anaerobic Sludge Blanket (UASB) reactor by introducing methods that make it to reduce inhibition possible in each process wastewater treatment. The used substrates, concentrated corn starch liquid (CSL) wastewater, modified starch, filtering and decoloring wastewater, ion refining wastewater, and mixed wastewater including modified starch and not including modified starch, are generated from molasses process. The seeding sludge is the digested sludge that had been applied to molasses wastewater. Batch test to reduce the inhibition factors that might be existed in each wastewater was examined. Based on the this test, the optimum operating factors according to alkalinity and pH variation was studied through the continuous test using three 5.5 L UASB reactor. The first reactor added $NaHCO_3$ to control alkalinity. The hydraulic retention time (HRT) reduced to 8 hours and the organic loading rate increased gradually. The second reactor changed the pH of influent from 7.0 to 6.0 using NaOH. The third reactor was operated without changes to compare the above two reactors. As the result, the inhibition in concentrated CSL wastewater was removed by adding iron (II). When trace metals were added to mixed wastewater not including modified starch, the digestability by gas production rate increased to more fifty percentage than mixed wastewater that was not adding the trace metals. The reason that the inhibition did not decreased in spite of adding trace metals and nutrients was influenced by high concentration generated during the acid fermentation. The UASB reactors using the mixed wastewater with the most effective performance were operated as 500 mg/L as $CaCO_3$ alkalinity and 6.0 pH at steady state, and at this time, the gas production rates were 283 and 311mL gas/g $COD_{added}$. The COD removal rates were 84.7 and 86.3%, respectively.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.29-36
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• 1984

Flow behaviors of rice starch-water systems containing 3-9% (w/v) of native and gelatinized starch solutions were studied with the capillary tube rheometer in the temperature range of $30-80^{\circ}C$. Flow behaviors of rice starch-water systems showed non-Newtonion behavior which could be expressed as ${\gamma}{\;}=\;{\psi}(^{\tau}g_c-{\tau}_yg_c)^N$. Flow parameters ${\psi}$, N and $^{\tau}_y$ were determined for native and gelatinized solutions. These parameters indicated that native rice starch solution shows a dilatancy and the gelatinized solution ranges from pseudoplastic to mixed type flow behavior with increasing concentrations. The value of flow behavior index for gelatinized solutions was about 1.2 in all samples but for native solutions, the values were 0.87-0.90. The values of yield stress, which were negligible below 5%, were increased with the increase in concentration from 5 to 9%. The value of consistency index was exponentially dependent on concentration and temperature. The values of activation energy for native and gelatinized solutions were 0.13-2.71 and 5.39-9.57 kcal/g mole, respectively.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.314-318
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• 1984

Rheological properties of gelatinized chestnut starch solution were investigated with a narrow gap rotational viscometer. The starch solutions at 1.2-1.8% concentration showed pseudoplastic behaviour with yield stress. At higher concentrations (1.65 and 1.8%), the starch solution showed more pseudoplastic tendency and time-dependent characteristics. Values of yield stress were small and independent of concentrations 1.2, 1.35 and 1.5%. Significant increase of yield stress was observed at 1.65% concentration. Consistency index was exponentially dependent on concentration and temperature. The activation energy for 1.65% starch solution was about 5 Kcal/g.mol.

• Preventive Nutrition and Food Science
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• v.3 no.1
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• pp.98-104
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• 1998

As an efffort ot construct LAB (latice acid bacteria), capable of utilizing starch as fermentation substrate without the aid of externally supplied enzymes, plasmid vectors containing the amyL($\alpha$-amylase/pullulansase gene) from Clostridium thermophydrosulfuricum, and glucoamylase cDNA from Asperigillus shirousamii were constructed and introduced itno E. coli and L. lactis. For expression in procaryotes , 1.9kb glucoamylase cDNA encoding the mature form of enzyme was PCR amplified and translationaly fused to a PCR amplified 260 bp fragment containing the promotor and secretion signals of amyl in the same reading frame. The production of $\alpha$-amylase, Apu, and glucoamlase in E. coli and L. lactis was confirmed by enzyme assay and zymography . Enzymeswere detected in both cellpellets and supernatants, indicating theworking of scretion signals in heterologous hosts. The efficiencies of secretion were varibale depending on the gene and host. The highest $\alpha$- amylase acitivity observed was 1.1 units and most activiity was detected from thecell pellets. The degree of gene expression in both hosts and the effect on the growth of hosts were examined.

• Korean Journal of Environmental Biology
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• v.21 no.4
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• pp.377-383
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• 2003

The functional Jeungpyuns with dietary fiber containing cereals such as brown rice and barley flour were developed and physiochemical properties were investigated. The water binding capacity had significantly the highest value of 28.4% in raw rice flour, followed by brown rice flour and barley flour. The lowest reducing sugar value was seen in unpolished rice substituted Jeungpyun with value of 5.420 (P<0.05). The amount of reducing sugar decreased slightly after steaming, due to the increased degree of sugar dissociation. The L value of the lightness decreased significantly with the substituted samples (P< 0.05). The barley substituted samples were darker than that of brown rice sample groups with less green and yellow color. Microstructures of starch particles after fermentation showed completely dispersed starch particles with air bubbles and sponge-like structure in all samples after steaming. Thus, functional Jeungpyun replaced with brown rice and barley flour can be successfully formulated and has been influenced by the physicochemical properties.

• Journal of Life Science
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• v.9 no.2
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• pp.5-8
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• 1999

We isolated a sphingonyelinase (SMase) inhibitor, which would be a potential reagent to regulate cell proliferation, oncogenesis, and inflammation, from a strain of Streptomyces sp.. In this paper, we report the optimal conditions for the production of SMase inhibitor, designed as sphinin, from Streptomyces sp. F50970. The optimal carbon and nitrogen source were 1% soluble starch and 0.05%-0.15% trypton. Most of monosaccharides and high concentration of soluble starch above 1.0% caused falling of pH and sphinin production. Zn2+, Cu2+, Fe2+, Mn2+, and Co2+inhibited cell growth and the production of sphinin. Inorganic phosphate promoted the sphinin production. Optimal initial pH for the production of sphinin was 7.5-8.0. Addition of CaCO3 to the medium resulted in an increase of inhibitor production. Based on these results, we designed a fermentation medium for the production of a SMase inhibitor, sphinin, from Streptomyces sp. F50970.

• Microbiology and Biotechnology Letters
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• v.14 no.4
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• pp.293-298
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• 1986

Sisomicin, which is one of aminoglycoside antibiotics, was produced by Micromonospora inyoensis. The effects of carbon sources on sisomicin production were studied in batch cultures. Starch, dextrin and maltose were good carbon sources for the production of sisomicin. However, when glucose was used, the antibiotic productivity decreased significantly due to a carbon catabolite regulation. The carbon catabolite regulation depends mostly on carbon catabolite repression, but not on carbon catabolite inhibition. On the other hand, the growth-production curves of batch cultures show that sisomicin is produced most actively during the idiophase.

• Korean journal of food and cookery science
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• v.14 no.3
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• pp.261-265
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• 1998

The activity and characteristics of ${\alpha}$-amylase in soy milk as well as in Jeungpyun batters were determined to investigate the enzyme system related to Jeungpyun preparation. ${\alpha}$-Amylase activity was detected in soy milk as well as in Jeungpyun batters. Soy milk had ${\alpha}$-amylase activity of 0.79 units/mg protein for gelatinized starch and 0.036 units/mg protein for raw starch. ${\alpha}$-Amylase in soy milk showed maximum activities at pH 5.92∼6.87 and at 60$^{\circ}C$ for both gelatinized starch and raw starch. ${\alpha}$-Amylase activities of Jeungpyun batters containing soy milk were 25.59 units/mg protein for gelatinized starch and 1.37 units/mg protein for raw starch. Jeungpyun batters without soy milk demonstrated ${\alpha}$-amylase activities of 3.37 units/mg protein for gelatinized starch and 0.49 units/mg protein for raw starch. ${\alpha}$-Amylase of Jeungpyun batters showed an optimal activity at pH 5.25 and at 60$^{\circ}C$ for both gelatinized and raw starch. The results demonstrated that Jeungpyun batters with soy milk showed significantly higher ${\alpha}$-amylase activity than the ones without soy milk.