• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.6-11
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• 1994

A cyclodextrin glucanotransferase(CGTase)-producing Bacillus sp. I-5 was isolated from soil and the enzyme exhibited the maximum reaction rate at pH 8.0 and $50^{\circ}C$. It was found that CGTase of I-5 produced ${\beta}-$ and ${\gamma}-CD$ mainly but the production ratio of cyclodextrins (CDs) was influenced by the buffer solution. Sodium acetate significantly stimulated the formation of ${\gamma}-CD$, increasing the content by 35%. The production of CDs was influenced by DE value of starch. The results indicated that DE value in the range of $3.5{\sim}6.0$ were most effective for the CD formation. CGTase was immobilized on the reversibly soluble-insoluble carrier, hydroxypropyl mothylcellulose acetate succinate. The immobilized CGTase was soluble at pH 7.5, and precipitated easily at pH 6.0. Enzyme reactor was designed to produce CD continuously. It was composed of three major stages-CD produttion by immobilized CGTase, conversion of the residual dextrin to glucose by amylase and glucoamylase and alcohol fermentation by yeasts to remove the glucose into alcohol. The yield of total CDs was 3.65g from 10g soluble starch.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1191-1196
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• 2012

The purpose of this study was to investigate the tyrosinase, xanthine oxidase, angiotensin converting enzyme (ACE) inhibitory effects, and nitrite scavenging abilities of Jubak (alcohol filter cake, AFC) hot water and ethanol extracts. Tyrosinase inhibitory effects of Jubak hot water and ethanol extracts were above 85%. Nitrite scavenging ability was higher at pH 1.2 than at pH 4.2 and 6.0. Nitrite scavenging abilities of water and ethanol extracts were above 90% at pH 1.2. Xanthine oxidase inhibitory effect of Jubak hot water and ethanol extracts showed a lower, and the effect did not different by hot water and ethanol. ACE inhibitory effects of Jubak hot water and ethanol extracts were approximately 43~53% and 36~47%, respectively. Overall, our results indicate that Jubak hot water and ethanol extracts may have tyrosinase and ACE inhibitory effects and nitrite scavenging ability, but no xanthine oxidase inhibitory effect. Therefore, Jubak has potential as a cosmetic raw material. Additionally, Jubak could be used as a food additive.

• The Korean Journal of Food And Nutrition
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• v.29 no.4
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• pp.538-546
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• 2016

This study was carried out to evaluate the quality characteristics of Korean domestic commercial white wines. Four sample wines were analyzed in terms of their pH, total acidity, volatile acidity, alcohol content, soluble solid, free $SO_2$, total $SO_2$, color, free sugar content, organic acid, volatile compounds, total polyphenol content, DPPH radical scavenging activity and sensory characteristics. The pH of wines ranged from 3.06 to 3.76 and their total acidity from 0.43 to 0.83% (v/v). The alcohol content of samples ranged from 9.4 to 12.8% (v/v) and their soluble solid contents from 9.9 to $12.3^{\circ}Brix$. The free $SO_2$ and total $SO_2$ contents of the W1 wine were lower than those of the other wines, while the color intensity, a (redness) and b (yellowness) of W1 wine were higher than the values of the other wines. The malic acid contents of the four wines indicated that complete malolactic fermentation (MLF) occurred in W1, incomplete MLF in W3, and was absent in W2 and W4. Aroma analysis resulted in identification of 10 alcohols, 11 esters, 2 ketones and 6 miscellaneous compounds. 2,3-Epoxybutane and 1-(ethenyloxy)-pentane levels in were significantly higher W1 than the other wines, while several types of ester predominated in W2, W3 and W4. W1 had the lowest sensory score among the four wines. Therefore, the quality characteristics of domestic white wines are considered to be acceptable.

• Korean journal of food and cookery science
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• v.17 no.3
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• pp.218-223
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• 2001

This study was conducted to evaluate the functional properties of onion, rosemary and thyme extracts which are the ingredients of onion Kimchi. Onion extract showed a significant difference in antioxidative effect based on peroxide value and thiocyanate method. Antioxidative activity of rosemary extract was similar to those of BHA and BHT. but thyme extract did not show any antioxidative effect.. Onion, rosemary, and thyme extracts showed antimicrobial activities against gram positive bacteria but onion and thyme extracts did not against E. coli, Candida, and molds. Rosemary extract demonstrated a strong activity against L. plantarum which is a major lactobacillus in Kimchi fermentation, and Micrococcus luteus. Onion, rosemary, and thyme extracts showed an effect or hangover relief effect by lowering the alcohol concentration of blood in rat. Blood pressure of the male spontaneous hypertensive rat was suppressed by onion extract after 3 days of feeding, but rosemary and thyme extracts were not effective for lowering blood pressure.

• Korean Chemical Engineering Research
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• v.49 no.1
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• pp.105-108
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• 2011

The increased concern for the security of the oil supply and the negative impact of fossil fuels on the environment, particularly greenhouse gas emissions, has put pressure on society to find renewable fuel alternatives. Compared to the traditional biofuel, ethanol, higher alcohols offer advantage as gasoline substitutes because of their higher energy density and lower hygroscopicity. For this reason, microbial fermentation is known as potential producers for sustainable energy carriers. In this study, bacterial responses including cellular and molecular toxicity were studied in three different microorganisms, such as Escherichia coli, Clostridium acetobutylicum, and Saccharomyces cerevisiae. In this study, it was analyzed specific stress responses caused by ethanol and buthanol using four different stress responsive genes, i.e. fabA, grpE, katG and recA. The expression levels of these genes were quantified by semi-quantitative reverse transcription-PCR. It was found that four genes have shown different responsive patterns when E. coli cultures were under stressful conditions caused by ethanol and buthanol, respectively. Therefore, in this study, the stress responsive effects caused by these alcohols and the extent of each stress response can be analyzed using the expression levels and patterns of different stress responsive genes.

• Microbiology and Biotechnology Letters
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• v.43 no.1
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• pp.56-64
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• 2015

It has been known for some time to the wine industry that non-Saccharomyces yeasts play an important role in increasing volatile components through the secretion of extracellular enzymes. The objective of this study was to investigate what types of enzymes are produced by 1,007 non-Saccharomyces yeast strains isolated from Korean fermented foods. Among 1,007 yeast strains, the 566, 45 and 401 strains displayed β-glucosidase, glucanase and protease activity, respectively. In addition, the 563 and 610 strains possessed tolerances against cerulenin and TFL, and the 307 strain was tolerant to 15% ethanol. Yeasts producing harmful biogenic amines and hydrogen sulfide were excluded from further study, and eventually 12 yeast strains belonging to the genera Wickerhamomyces, Hanseniaspora, Pichia, Saccharomyces were identified, based on the 26S rRNA gene sequences. Among the 12 strains, the 9 and 5 strains possessed glucose and ethanol tolerance, respectively. Yeasts belonging to the genus Saccharomyces produced more than 8% alcohol, but non-Saccharomyces yeasts produced only 3% alcohol.

• Applied Biological Chemistry
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• v.24 no.1
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• pp.21-28
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• 1981

Brewing method and quality of 15 samples of traditional Kochuzang in Junrabook-do area were investigated. Average combination ratio of glutinous rice: Meju (soybean Koji): red pepper powder was 2 : 0.7 : 1.1. In order to improve the taste of Kochuzang, some amount of natural soysauce was added in the Kochuzang at early stage of fermentation. Average content of sodium chloride was 7.32%; amino nitrogen, 123.3%; total sugar, 31.9%; reducing sugar, 19.4%; ethyl alcohol, 1.13% and the activity of acid protease was 0.07; liquefying amylase, 9.67 and saccharogenic amylase was 15.82. Five samples were selected as excellent Kochuzang through sensory evaluation. These samples were similarly strong in hot and sweet taste with alcoholic flavor, glossy surface and brownish red color.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1189-1194
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• 2011

This study was conducted to compare the quality characteristics of Korean traditional wine fermented from different rice cultivars. Two kinds of rice cultivars, Seolgaengbyeo and Chucheongbyeo, were used. The hardness values of Seolgaengbyeo and Chucheongbyeo were 2126.6 g/sec and 4056.1 g/sec. The alkali digestion value (ADV) and amylose contents of Seolgaengbyeo and Chucheongbyeo were 6.6 and 6.4, 19.8 and 19.3%, respectively. Amylogram results were not significantly different between Seolgaengbyeo and Chucheongbyeo using a rapid visco analyzer (RVA). After fermentation for 7 days, the alcohol contents of the fermented wines ranged from 17.34 to 17.53%. The pH, total acidity, and glucose contents of the wines fermented with Seolgaengbyeo and Chucheongbyeo were 3.63 and 3.64, 0.17 and 0.17 mg/mL, 3.22 and 3.65 mg/mL, respectively. Finally, sensory evaluation of wine fermented with Seolgaengbyeo showed better taste than that of wine made with Chucheongbyeo.

• Journal of Life Science
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• v.18 no.4
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• pp.447-453
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• 2008

Zinc is an essential trace element in Human Being. Highly zinc containing yeast strain isolated from the tropical fruit, rambutan and the zinc concentration in this yeast strain was 306 ppm (30.6 mg%)per dry matter basis. This strain was found to be a rounded type, normal size, and multi-polar budding. Phylogenetic analysis using the ITS1-5.85 rDNA sequences from isolated strain is most similar to yeast Saccharomyces cerevisiae at the level of nucleotide sequence identity at 99%. This strain was produced alcohol by about 12% using fully colonized koji-rice with Aspergillus oryzae. In conclusion, the isolated strain was found to be closely related to the S. cerevisiae based on its morphological and physiological properties, and alcohol fermentation. The phylogenetic analysis of strain FF-10 using ITS 5.8S rDNA sequence data also supported the closely related to the S. cerevisiae. Accordingly, the isolated yeast was named as S. cerevisiae FF-10. Further studies on the best culture conditions for zinc production from zinc-enriched S. cerevisiae FF-10 are under investigation.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.603-610
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• 2001

The quality characteristics of soy yogurt prepared with different proteolytic enzymes and starter culture were evaluated. In order to facilitate the growth of lactic acid bacteria and subsequent production of lactic acid, soy protein isolate(SPI) was hydrolyzed using three kinds of proteases; one extracted from Aspergillus oryzae, bromelain and ${\alpha}-chymotrypsin$. The cultural systems employed thereafter for lactic fermentations were: 1) Bifidobacterium bifidum, 2) B. bifidum and Lactobacillus acidophilus, 3) B. bifidum and Lactobacillus bulgaricus. In soy yogurt, pH was more decreased by mixed culture method than single culture method with the accumulation of lactic acid. Viable cells of lactic acid bacteria in soy yogurts were measured $10^8$ CFU/g by the single culture method while $10^9$ CFU/g by the mixed culture method except ${\alpha}-chymotrypsin$ treatment. The amount of free amino acids in soy yogurts were substaintially increased by enzyme treatment. Viscosity was decreased by enzyme treatment, resulting in higher viscosity by ${\alpha}-chymotrypsin$ treatment. Water holding capacity was found to be higher in the single culture method in case of enzyme treatment. Among the various volatile flavor components isolated and identified after enzyme hydrolysis, acetaldehyde, ethanol, diacetyl, butyl alcohol contents tended to increase by lactic fermentation.