• Korean Journal of Microbiology
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• v.37 no.3
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• pp.177-181
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• 2001

It is previously reported that Bacillus licheniformis B1 strain isolated from nature was successfully used for Chungkookjang fermentation. Antioxidant activity of its powder was determined in this study. Sephadex G-75 gel filtration chromatography was performed, far soluble fractions of the powder extracted by distilled water. The soluble fractions were separated into large and small fractions. The substance 1,1-diphenyl-2-picrylhydrazyl (DPPH) was used as an electron acceptor. Antioxidant activity was found in the small fractions. Five% solution of the Chungkookjang powder was the most effective in the extraction of antioxidant substances from the powder. It was proven in this study that strong antioxidant activity still remained in the Chungkookjang powder.

• The Korean Journal of Mycology
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• v.30 no.2
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• pp.142-146
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• 2002

In order to develop a new traditional liquor by using Paecilomyces japonica, alcohol fermentation condition was investigated. Ethanol was produced maximally when 1% P. japoniea and 10% koji were added into mash and fermented by Saccharomyces cerevisiae at $25^{\circ}C$ for 15 days. Sensory evaluation and physiological functionalities of P. japonica traditional liquors made by different addition ($0.1{\sim}2.0%$) of the fungus were also determined and compared. As 0.1% P. japonica was added to mash, the liquor was best acceptable, and its fibrinolytic activity and nitrite scavenging activity were 11.2U and 19.8%, respectively.

• Microbiology and Biotechnology Letters
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• v.43 no.2
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• pp.169-174
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• 2015

Nuruk has been used as fermentation starter in the alcohol industry for some time in Korea. Various bioactivities, such as antiproliferative and anti-obesity, of R4 nuruk made from Rhizopus oryzae KSD-815 have been previously reported. In this study, the hot water and ethanol extract of R4 nuruk and their subsequent organic solvent fractions were prepared, and their antithrombosis activities were evaluated. The ethylacetate fraction showed strong anti-coagulation activity, and the ethylacetate and butanol fraction from hot water extract demonstrated platelet aggregation inhibitory activity, without hemolysis against human RBC. Our results suggest that R4 nuruk has the potential to act as a new anti-thrombosis agent.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.3
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• pp.273-280
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• 2020

Volatile compounds in fermented ascidians Halocynthia roretzi were analyzed to identify key flavor compounds using SPME/GC/MSD (solid phase microextraction/gas chromatography/mass selective detector) after 60 days of fermentation at 5℃. The control was chopped ascidians subject to anti-browning and 4% salt treatment. product A was made from product C by adding an alcohol extract of red peppers and onion peel, 0.1% of glucose, and 0.55% of mixed amino acids (MAA; 0.05% Glu, 0.1% Pro, 0.3% Ala, and 0.1% Gly). After blanching and anti-browning treatment of chopped ascidians, Product B1 was made by adding 3% anchovy sauce and 6% sorbitol. Product B2 was made by adding 0.1% glucose and 0.55% MAA to Product B1. In total, 78 compounds were identified, including 31 alcohols, 15 aldehydes, and 10 ketones. The alcohols included 12 compounds from the C8-C10 series with floral and fruit odors, including octanol, 3-methyloctanol, 2,6-dimethyl-1-heptanol, (E)-5-octen-1-ol, 6-methyloctanol, (E)-3-octen-1-ol, (E)-3-decen-1-ol, (Z)-1,5-octadien-3-ol, and nonanol. These were detected in high amounts in ascidians and all fermented products. Aldehydes (octanal, (E)-2-octenal, 2,4-heptadienal, and nonanal) and ketones (1-oten-3-one and 2-heptanone) with fatty and mushroom odors were detected as major compounds, whereas nine ethyl esters were detected only in product A.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.5
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• pp.439-446
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• 2003

Various volume of water for the optimal brewing condition of the Korean distilled liquor produced by liquefaction of rice and corn starch was investigated Pilot brewings were carried out by the liquefaction of 5kg of rice and 10kg of corn starch with 150%, 200% and 250% of water regarding the amount of rice and corn starch. The pH, alcohol production and total acidity were normal during the fermentation process. The yield was proportional to the amount of water added and the highest yield was obtained by 250% of water addition without loss of quality. All the test results were not significantly different by the one-way ANOVA and Duncan's multiple range test at p<0.05 and the flavor profiles were also not different according to the amount of water added. As a result, 250% of water addition was the most economical and optimal brewing condition in this study.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.644-648
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• 2005

Dextranase (${\alpha}$-1,6-D-glucan-6-glucanogydrolase:E.C. 3.2.1.11) catalyzes the hydrolysis of ${\alpha}$-(1.6) linkages of dextran. A lsd1 gene encoding an extracellular dextranase was isolated from the genomic DNA of L. starkeyi. The lsd11 gene is a synthetic dextranase (lsd1) after codon optimization for gene expression with Pichia pastoris system. A open reading frame of lsd11 gene was 1827 bp and it was inserted into the pPIC3.5K expression vector. The plasmid linearized by Sac I was integrated into the 5'AOX region of the chromosomal DNA of P. pastoris. The lsd11 gene fragment encoding a mature protein of 608 amino acids with a predicted molecular weight of 70 kDa, was expressed in the methylotrophic yeast P. pastoris by controling the alcohol oxidase-1 (AOX1) promoter. The recombinant lds11 was optimized by using the shake-flask expression and upscaled using fermentation technology. More than 9.8 mg/L of active dextranase was obtained after induction by methanol. The optimum pH of LSD11 was found to be 5.5 and the optimum temperature $28^{\circ}C$.

• BMB Reports
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• v.32 no.1
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• pp.39-44
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• 1999

Pyruvate decarboxylase (PDC) catalyzes the conversion of pyruvate to acetaldehyde as the penultimate step in alcohol fermentation. The enzyme requires two cofactors, thiamin diphosphate (ThDP) and $Mg^{2+}$, for activity. Zymomonas mobilis PDC shows a strong preference for pyruvate although it will use the higher homologues 2-ketobutyrate and 2-ketovalerate to some extent. We have investigated the effect of mutagenesis of valine 111 and leucine 112 on the substrate specificity. V111 was replaced by glycine, alanine, leucine, and isoleucine while L112 was replaced by alanine, valine, and isoleucine. With the exception of L112I, all mutants retain activity towards pyruvate with $k_{cat}$ values ranging from 40% to 139% of wild-type. All mutants show changes from wild-type in the affinity for ThDP, and several (V111A, L112A, and L112V) show decreases in the affinity for $Mg^{2+}$. Two of the mutants, V111G and V111A, show an increase in the $K_m$ for pyruvate. The activity of each mutant towards 2-ketobutyrate and 2-ketovalerate was investigated and some changes from wild-type were found. For the V111 mutants, the most notable of these is a 3.7-fold increase in the ability to use 2-ketovalerate. However, the largest effect is observed for the L112V mutation which increases the ability to use both 2-ketobutyrate (4.3-fold) and 2-ketovalerate (5.7-fold). The results suggest that L112 and, to a lesser extent, V111 are close to the active site and may interact with the alkyl side-chain of the substrate.

• The Korean Journal of Food And Nutrition
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• v.30 no.3
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• pp.599-608
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• 2017

This study investigated the quality characteristics and volatile flavor components of aronia wine (Aronia melanocarpa (0~100%)). After 12 days of fermentation, the alcohol contents of aronia wines ranged between 9.0~12.0%. The pH level and total acidity of aronia wines were 3.20~3.68 and 0.57~0.76 g/100 mL, respectively. The organic acid analysis of wine containing 100% aronia, revealed malic acid content at 3.70 mg/mL, followed by tartaric acid, lactic acid, and citric acid. As the aronia content increased, both the total polyphenol content and the antioxidant activity (the DPPH radical scavenging activity) also significantly increased. The total polyphenol content was the highest in the wine with 100% aronia (461.33 mg%), and the antioxidant activity showed the highest values in the wine with 100% aronia (91.91%). Volatile flavor component analysis of aronia wines identified 8 alcohols, 12 esters, 4 ketones, and 7 other compounds. In the sensory evaluation, the color, flavor, and taste of wine with 20% aronia showed higher values than other aronia wines. Based on the results of the present study, we suggest that 20% aronia is most beneficial in improving the quality as well as sensory characteristics of the wine.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.935-939
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• 1996

A Candida sp. strain was isolated from honeycombs and used to produce erythritol, which was identified by HPLC and gas chromatography-mass spectrometry. This strain grown in the YPD medium containing 100 g/l of glucose was able to produce 21 g/l of erythrtiol without formation of by-products such as glycerol and ethanol. The yield of erythritol production was further improved by growing in the YPD medium containing 300 g/l of sucrose. The maximum erythritol concentration, 80.2 g/l was obtained with an erythritol yield of 0.345 g erythritol/g sucrose and productivity of 0.472 g/l hr.

• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.109-113
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• 2002

To develop a new traditional liquor by using chamomile, the condition of alcohol fermentation was investigated by the addition of 5%, 10%, 15% nuruk, and 20% chamomile into mash. The maximum amount of ethanol was produced when 20% chamomile and 15% nuruk were added to cooked rice and fermented by Saccharomyces cerevisiae at $25^{\circ}C$ for 10 days. The acceptability and physiological functionalities of chamomile liquors with different concentrations $(1{\sim}20%)$ of chamomile were compared. The C-5 chamomile liquor which was prepared by adding 5% chamomile into mash showed the best acceptability in the sensory evaluation test and color test, and its fibrinolytic activity, tyrosinase inhibitory activity, and nitrite scavenging activity were good.