• KSBB Journal
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• v.27 no.4
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• pp.251-256
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• 2012

In this study we investigated the effect of temperature on the two-stage fermentation of Makgeolli using uncooked germinated black rice. The fermentation processes were conducted at $15^{\circ}C$ for three weeks and $25^{\circ}C$ for 7 days. The pH of Makgeolli at $25^{\circ}C$ increased from pH3.0 to pH 4.2, which was consistent with that at $15^{\circ}C$. In contrast total acidity of Makgeolli at $15^{\circ}C$ was about half of that at $25^{\circ}C$ (0.36% and 0.59%, respectively). By the 7 days-fermentation at $25^{\circ}C$, 11% of alcohol was produced, whereas three weeks were required for the same alcohol production at $15^{\circ}C$. In the case of sugar contents, the amounts of total glucose-equivalent reducing sugars and glucose increased at the end of the fermentation at $25^{\circ}C$ up to 2.25 mg/mL and 3.4 mM, respectively, whereas those at $15^{\circ}C$ were maintained at very low levels (0.18 mg/mL and 0.1 mM, respectively). Such limited supplement of sugars at $15^{\circ}C$ seemed to affect metabolism of yeast, resulting in different composition of organic acid. At $25^{\circ}C$, citric acid that was 73.4 ppm at the initial fermentation was consumed completely, whereas 20 ppm of citiric acid was remained at $15^{\circ}C$. In addition, acetic acid and lactic acid in Makgealli at $15^{\circ}C$ were 53% and 14% of those at $25^{\circ}C$.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.20-27
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• 2001

An effective method for production of glucose was developed using enzymatic hydrolysis of Suwon poplar by the cellulase. Enzymatic hydrolysis of wood is the reaction to produce glucose from wood using enzyme which derives from microorganism. Glucose can be transferred easily to ethanol by fermentation. Ethanol is the starting material for producing acetone, butanol, citric acid and lactic acid. The mechanism of the enzymatic hydrolysis of cellulose are reasonably explained in terms of the sequential action of three different types of enzymes, endo-cellulase, ex-cellulase, and $\beta$ -glucosidase. The goal of this work was to investigate the cellulose hydrolysis pretreated polar with various concentration NaOH, the crystallinity of cellulose, lignin contents and the degree of hydrolysis.

• Journal of Microbiology
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• v.43 no.1
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• pp.28-33
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• 2005

The purpose of this study was to develop a multipurpose incubator, without the gas cylinders (bottles) which are required for $H_2$ and $CO_2$ supplementation. In our bottle-free multipurpose incubator, the $H_2$ and $CO_2$ were generated by chemical reactions induced within the chamber. The reaction between sodium borohydride and acetic acid at a molar ratio of 1:1 was used to generate $H_2$, according to the following formula: $4NaBH_4+2CH_3COOH+7H_2O{\rightarrow} 2CH_3COONa+Na_2B_4O_7+16H_2$, whereas the other reaction, citric acid and sodium bicarbonate at a 1:1 molar ratio, was used to generate $CO_2$, according to the following formula: $C_6H_8O_7+3NaHCO_3{\rightarrow}Na_3(C_6H_5O_7)+3H_2O+3CO_2$. Five species of obligate anaerobic bacteria, one strain of capnophilic bacterium, and one strain of microaerophilic bacterium were successfully cultured in the presence of their respective suitable conditions, all of which were successfully generated by our bottle-free multipurpose incubator. We conclude that, due to its greater safety, versatility, and significantly lower operating costs, this bottle-free multipurpose incubator can be used for the production of fastidious bacterial cultures, and constitutes a favorable step above existing anaerobic incubators.

• Journal of Ginseng Research
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• v.9 no.1
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• pp.24-35
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• 1985

Rusty root of ginseng has been known as one of the limiting factors in ginseng production in Korea. An attempt was, therefore, made to elucidate biological and chemical natures of the rusty root, and the redox Potential of the ginseng cultivated soils were measured and compared with diseased and non-diseased soils. Reddish discoloration was most frequently observed on the epidermis of ginseng root and the pigments were accumulated in all epidermal cells of the diseased lesions. The lower the redox potential of the ginseng cultivated soil was, the more severe the rusty root was observed. Fe content in the diseased epidermis was 3 times higher than that of healthy one. Organic acids such as oxalic, malonic, succinic, and citric acids were also higher in the mss root than in the healthy one. Thin layer chromatogram of phenolic acid fractions obtained from the epidermal cells of the rusty root of ginseng exhibited 3 to 4 unidentified substances not found in the healthy root. Also lignification of the epidermal cells and the activity of phenylalanine ammonia lyase were greater in the rusty root than the healthy root. Colony formation and conidia production of F. solani, And mycelial growth and sclerotium formation of Sclerotinia sp. isolated from ginseng root were suppressed in a nutritionally minimal medium supplemented with water extract of rusty ginseng root epidermis. It is, therefore, suggested that rusty root of ginseng is caused by unfavorable rhizosphere environmental stress or stresses resulting abnormal metabolism in the root as a selfdefence mechanism of non-specific resistance responses.

• Journal of Mushroom
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• v.3 no.4
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• pp.133-139
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• 2005

Fruiting bodies of Cordyceps have been regarded as popular folk and effective medicines to treat human diseases such as asthma, bronchial and lung inflammation, and kidney disease. Cordyceps pruinosa (Clavicipitaceae; Hypocreales; Ascomycotina) has received special attention for medicinal purpose due to its various physiological activites. The nucleoside derivative N6-(2-hydroxyethyl) adenosine (HEA) isolated from it showed a $Ca^{2+}$ antagonistic effect and negative inotropic response. The artificial production of fruiting body of C. pruinosa has not been tried successfully yet by using living silkworm substrate. To develop techniques for the production of C. pruinosa stromata on a large scale, the infection of Bombyx mori with C. pruinosa and the growth characteristics of stroma of C. pruinosa were investigated. Also, studied about biological activities of fruiting body formed on silkworm. Infection rate of the silkworm pupae with C. pruinosa was the highest in injection inoculation. The formation of the fruiting body of C. pruinosa was quite good in the room controlled at $21{\sim}25^{\circ}C$, over 91% of relative humidity and over 1500 lx. Glucose concentration was high in the fruiting bodies of the silkworm pupae infected with C. pruinosa on a dry weight basis. The most abundant amino acid in the fruiting bodies was arginine and phenylalanine. The fruiting bodies of silkworm pupae infected with C. pruinosa was rich in oleic acid. The high amount of citric acid was found in the fruiting bodies of silkworm pupae infected with C. pruinosa.

• Journal of Dairy Science and Biotechnology
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• v.33 no.1
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• pp.17-25
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• 2015

The present study was carried out to evaluate the preparation of the fermented milks with rice bran and to prove that the bacteria used are necessary for providing amino acids in this process. The rice bran on fermented milk with Streptococcus thermophilus (ST-body1) and Lactobacillus casei (LC-10). The fermentation limit was set until acidimetry score reaches 1. There are reports of titratable acidity, pH, viable cell count and amounts of organic acids affecting amino acid production about physical and chemical analysis measured using HPLC. Finally, sensory test was surveyed. In this study, the rate of acidification was higher in the fermented milk with rice bran than in the common fermented milk. In case of the number of cells was $1.0{\times}10^8CFU/mL$ in group. The lactic acid and citric acid content in yogurts prepared with rice bran using Streptococcus thermophilus (ST-body1) and Lactobacillus casei (LC-10) was higher than that in the control yogurt. Amino acids derived by rice bran were effected in fermentation for each bacteria's necessary amino acid production, and it made bacteria growth larger. From the physical test of the fermented milk with rice bran, flavor, texture, sweetness, overall taste of the fermented milk of Streptococcus thermophilus (ST-body1) were found to be much better than those of the other groups. The results obtained for the fermented milk prepared with rice bran using Streptococcus thermophilus (ST-body1) are significant.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.235-241
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• 2003

Yogurt base was prepared from whole and skin milk added with $0.5{\sim}2.0%\;(w/v)$ of cultured ginseng ethanol extract and fermented with lactic acid bacteria (Streptococcos thermophilus : Lactobacillus bulgaricus=1:1) at $37^{\circ}C$ for $24{\sim}30\;h$. Quality characteristics of the yogurt were evaluated in terms of acid production, number of viable cells, viscosity, and sensory property during lactic acid fermentation. Total contents of amino acids and some organic acids were analyzed. Addition of cultured ginseng extract stimulated the growth of lactic acid bacteria, and enhanced acid production and viscosity of yogurt. Total contents of amino acids of 0.5% cultured ginseng-added yogurt were higher than control group before fermentation, whereas glutamic acid, cysteine, valine, and phenyalaine contents increased after 30 h incubation. Contents of lactic, citric, and formic acids of 0.5% cultured ginseng-added yogurt increased during fermentation for 24 h. whereas decreased thereafter. Sensory scores of yogurts added with 0.5 and 1 % cultured ginseng extract were significantly higher than other groups in taste and overall acceptability. When cultured ginseng yogurt was kept at $5^{\circ}C$ for 15 days, its quality-keeping property was relatively good.

• Animal Bioscience
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• v.36 no.3
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• pp.506-520
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• 2023

Objective: Japanese Brown (JBR) cattle, especially the Kochi (Tosa) pedigree (JBRT), is a local breed of moderately marbled beef. Despite the increasing demand, the interbreed differences in muscle metabolites from the highly marbled Japanese Black (JBL) beef remain poorly understood. We aimed to determine flavor-related metabolites and postmortem metabolisms characteristic to JBRT beef in comparison with JBL beef. Methods: Lean portions of the longissimus thoracis (loin) muscle from four JBRT cattle were collected at 0, 1, and 14 d postmortem. The muscle metabolomic profiles were analyzed using capillary electrophoresis time-of-flight mass spectrometry. The difference in post-mortem metabolisms and aged muscle metabolites were analyzed by statistical and bioinformatic analyses between JBRT (n = 12) and JBL cattle (n = 6). Results: A total of 240 metabolite annotations were obtained from the detected signals of the JBRT muscle samples. Principal component analysis separated the beef samples into three different aging point groups. According to metabolite set enrichment analysis, post-mortem metabolic changes were associated with the metabolism of pyrimidine, nicotinate and nicotinamide, purine, pyruvate, thiamine, amino sugar, and fatty acid; citric acid cycle; and pentose phosphate pathway as well as various amino acids and mitochondrial fatty acid metabolism. The aged JBRT beef showed higher ultimate pH and lower lactate content than aged JBL beef, suggesting the lower glycolytic activity in postmortem JBRT muscle. JBRT beef was distinguished from JBL beef by significantly different compounds, including choline, amino acids, uridine monophosphate, inosine 5'-monophosphate, fructose 1,6-diphosphate, and betaine, suggesting interbreed differences in the accumulation of nucleotide monophosphate, glutathione metabolism, and phospholipid metabolism. Conclusion: Glycolysis, purine metabolism, fatty acid catabolism, and protein degradation were the most common pathways in beef during postmortem aging. The differentially expressed metabolites and the relevant metabolisms in JBRT beef may contribute to the development of a characteristic flavor.

• Food Science and Preservation
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• v.24 no.2
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• pp.254-265
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• 2017

For the production of ${\gamma}-aminobutyric$ acid (GABA) contents increased Seomaeyaksuk fermentant, 0, 0.25, 0.5 and 1.0% of monosodium galutamate (MSG) was added in Seomaeyaksuk water extract 15% contained Sikhye and inoculated with Lactobacillus brevis (KI271266). Physicochemical properties were sampling and analyzed at each 1 day during 3 days fermentation. Goes on fermentation periods, the turbidity was gradually reduced, but lightness and the yellowness was increased, redness was decreased. Soluble solid was also decreased. The reducing sugars content were also decreased during fermentation. pH was 4.65-4.83 before fermentation but it was lower 3.15-3.68 after three days fermentation. The GABA contents increased by fermentation periods and it was the highest in MSG 1.0% added sample (354.38 mg/L). Fructose, glucose and sucrose contents were 50-67% decreased at three days fermentation than before fermentation. Among the organic acids, propionic acid, oxalic acid, citric acid and fumaric acid contents were decreased and lactic acid, acetic acid and succinic acid were increased during fermentation periods. Contents of total polyphenol and DPPH radical scavenging activity were the highest in MSG 0.5% added sample. From these results, we confirmed that increasing of GABA content when the manufacturing of Seomaeyaksuk lactic acid fermentation product, is possibile by addition of MSG without affecting physicochemical characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1341-1350
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• 2007

This study was designed to ultimately develop a highly efficient mass production technology of bacterial cellulose isolated from the citrus gel fermented by G. hansenii TL-2C. Pilot equipment made with FRP vessel length (665 mm) ${\times}$ width (375 mm) ${\times}$ height (210 mm) was developed for mass production of the citrus gel. To develop the optimal conditions for mass production of citrus gel, comprised of citrus juice (6,000 mL) diluted 100 times, containing 5% seed bacteria, 10% sucrose, and 1% ethanol, citrus juice was fermented at $30^{\circ}C$ for 14 days, and gel productivity in pilot system was examined. BC was isolated and purified from the citrus gel, and their chemical composition and physicochemical properties were investigated.