• Applied Biological Chemistry
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• v.40 no.5
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• pp.365-368
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• 1997

This study was carried out to investigate the optimum mashing and maturing conditions for Korean traditional Kanjang(soy sauce) production and to reduce the fermentation period. The effects of maturing time of soy sauce mash, maturing temperature, salt concentration and the ratio of Meju to salt brine on the quality of Kaniang(total nitrogen, pH and color) were examined. Soy sauce pigments and about 90% of N constituents contained in soybean Meju(Koji) in soy sauce mash were degraded and solubilized into liquid portion (soy sauce) of the mash within five days of maturing at $30^{\circ}C$ with the mashing ratio(weight/volume) of 1 : 4 of soybean(as raw soybean) to 20% salt brine. No remarkable effects of soy sauce maturing temperature in the range of $5^{\circ}C{\sim}30^{\circ}$ on the digestion and solubilization of N components and pigment extraction during five days of soy sauce mash maturing were observed. Optimum mashing salt brine concentration for the digestion and solubilization of N components and pigment extraction during soy sauce maturing at $30^{\circ}C$ were observed to be in the range of $15{\sim}20%$. The suitable mashing ratio of Meju to salt brine (wt./vol.) to match N content of the standards of identity of Korean traditional Kanjang(soy sauce) was found to be below 1 : 5.

• Applied Biological Chemistry
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• v.43 no.3
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• pp.163-168
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• 2000

To remove phosphate accumulated in the soil and water, Acinetobacter lwoffi PO8 possessing a high ability to accumulate phosphate was isolated from a active sludge. Bacterium was cultured in the liquid medium containing $150\;{\mu}g/mL$ of phosphate at $30^{\circ}C$ in different culture conditions to examine intracellular phosphate uptake. The initial pH in the range of $7.5{\sim}8.5$ was effective on the growth and phosphate uptake of the strain. Glycerol and arabinose used as a carbon sources showed 93 and 91% the phsphate uptake, respectively. Among the nitrogen sources, ammonium salt such as $NH_4NO_3$ and $(NH_4)_2SO_4$ was effectively utilized on the phosphate uptake compared with amino compounds. The rate of phosphate uptake of $NH_4NO_3$, and $(NH_4)_2SO_4$, was 95 and 96%, respectively The growth and Phosphate uptake ability in the strain were significantly promoted when metal ions were added in the medium; $Co^{2+}$, however, was not utilized by the strain. The capacity of phosphate uptake was enhanced to $10{\sim}20%$ when arginine, methionine, or lysine was added. Using $^{32}P$ to examine the uptake Pattern of intracellular phosphate, experiment result showed that polyphosphate was largely found in the fraction of intracellular inorganic phosphate of Acinetobacter lwoffi PO8.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.152-159
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• 2010

The influence of urushiol, as an allergen on laccase property of Fomitella fraxinea was investigated. The enzyme production was reached to the highest level after 10 days, cultivation and the activity and mycelial biomass were increased by 2.5 and 1.5 folds, respectively, by adding urushiol in the culture medium. In liquid cultures using a Cu Mn-free medium, laccase lactivity was decreased by 3.8-9.2 folds, with similar dry cell weight. Two isoenzymes, were purified using anion exchange, hydrophobic interaction and size-exclusion chromatographies. Both isoenzymes are monomeric proteins, with $M_W$ around 67 kDa(Lac1) and 66 kDa(Lac2), and isoelectric points of 3.67 and 3.81. The optimal conditions for purified isoenzymes were found to be pH 4.5-5.0 and $30-35^{\circ}C$. Activity decreased by the addition of $Fe^{2+}$, $Mg^{2+}$, $Na^+$, and strongly inhibited by EDTA and sodium azide.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.160-163
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• 2006

Brown rice contains rice bran and germ with higher nutritional value and dietary fiber content compared with the polished rice. However, brown rice has a limitation of poor digestion. fermented brown rice could be better nutritional source and improve digestibility. Therefore, we tried to select good fermentative microorganisms which have nutritional values with high amylase and protease activities, and probiotic effects. Nineteen micro-organisms, including eight Bacillus strains isolated from Chongkukjang and 11 lactic acid bacteria, were screened for the fermentation ability and enzyme production. The liquid broths containing 2.5%(w/v) of raw brown rice powder as a sole nutritional source were used for culture media. Among the strains tested, all of the Bacillus strains and two lactic acid bacteria (Leuconostoc gelidum and Pediococcus pentosaceus) showed increase in cell population and enzyme activities. The viable cell counts of all the Bacillus strains and two lactic acid bacteria exceeded $10^7 CFU/mL$. The maximal enzyme activities produced by Bacillus sp. Bl, Bacillus sp. B2, Bacillus sp. B11, L. gelidum and P. pentosaceus were 17.85, 17.50, 17.10, 17.10 and 3.24 U/mL for amylase and 22.48, 22.04, 23.76, 12.13, and 3.4 U/mL for pretense, respectively. Therefore, the results of this study demonstrated that the above strains could be potential starters for the fermentation of raw brown rice.

• Korean Journal of Microbiology
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• v.34 no.4
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• pp.212-218
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• 1998

An obligately methylotrophic bacterium which produces extracellular polysaccharide (EPS) was isolated through methanol-enrichment culture technique. The isolate was aerobic, nonmotile, and gram negative rod and exibited catalase, but no oxidase, activity. Plasmid, carotenoid, and poly-${\beta}$-hydroxybutyric acid were not found. The guanine plus cytosine content of DNA was 52-56%. The isolate was found to grow only on methanol and monomethylamine. Growth was optimal ($t_d=2.4h$) at $35^{\circ}C$ and pH 6.5 in a mineral medium containing 0.5% (v/v) methanol, 25 mM phosphate, and 0.212% ammonium sulfate. Methanol was assimilated through the ribulose monophosphate pathway. Maximun amount of EPS was produced in cells growing at the mid-stationary growth phase at $30^{\circ}C$ in a mineral medium (PH 6.5) containing 1.0% (v/v) methanol in the CIN ratio of 54.7. Thin-layer chromatographic and high performance liquid chromatographic analysis revealed that the EPS was composed of glucose and galactose. EPS which was not treated with ethanol (Pbe) exhibited stable viscosity under various concentrations of salts and temperatures hut showed high viscosity at low pH. EPS precipitated with ethanol (Pae) was found to be more stable in viscosity than the Pbe at various salt concentrations, temperatures, and pH. The Pae also exhibited higher viscosity than the Pbe and xanthan gum. Scanning electron microscopy revealed that the lyophilized Pbe and Pae have a multi-layered structure and a structure of thick fibers, respectively.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.103-108
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• 2001

The in vitro plantlets of cassava (Manihot esculenta Crantz cv. MColl 22) could be regenerated from nodal explant cultures in a liquid MS basal medium containing 0.01 mg/L zeatin for 2 weeks. The plantlets of 1.5∼2.5 cm in shoot length were transplanted to a glass bottle containing fine sand and acclimated under non-sterile conditions after excising their intact roots by: 1) prune leaving roots base of 1∼1.5 cm; 2) complete removal of roots; and 3) cutting off the rooting zone. The majority of in vitro-formed intact roots continued growth after transferred to soil, and all of the damaged roots stopped further growth. The plantlets with excised roots began to develop new roots within 7∼10 days after being transferred to a glass bottle, and a few of the pruned roots developed lateral roots from the remaining portion. Pruning and removal of in vitro roots resulted in a high survival rate (>87%), and did not significantly affect ex vitro root regeneration and acclimation, but the plantlets in which the rooting zone had been cut-off showed 73% survival rate. Pruning or removal of in vitro roots before transfer of plantlets is recommended for useful method of commercial micropropagation because of easier handling and high survival rate of plantlets.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.77-83
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• 2013

In this study, we observed optimal conditions and suitable bacteria for the fermentation of steam-dried ginseng berry extracts (SGB) and determined antioxidant effects of the fermented extracts. Five bacteria (Lactobacillus fermentarum, L. plantarum, L. brevis, L. casei, Bacillus subtillis) were examined on their growth activities and viabilities in various culture temperatures ($25-35^{\circ}C$) and concentrations (25-100%). L. plantarum was considered to be the most suitable bacteria for the fermentation in both growth activity and viability. Moreover, the extracts fermented with L. plantarum showed more potent antioxidant efficacy in both 1,1-diphenyl-2-picrylhydrazyl radical and hydroxyl radical scavenging assay. High performance liquid chromatography analysis revealed that fermentation with L. plantarum changed the contents and components of ginsenosides. In conclusion, these data suggest that L. plantarum efficiently ferment SGB and the fermented extracts may have therapeutical values against oxidative stress and be a good candidate in adjuvant therapy where ginsenoside would be the main composition.

• Journal of Life Science
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• v.29 no.2
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• pp.158-163
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• 2019

The purpose of this study was to isolate a new marine agarase-producing bacterium. Agarase can hydrolyze agar and agarose to produce agarooligosaccharides or neoagarooligosaccharides, which possess many physiological functions. Strain DH-3 was isolated from seawater collected from the coast of Yeosu at Jeollanam province, Korea. A 16S rDNA sequence analysis showed this strain to be Persicobacter sp. DH-3. Extracellular agarase was prepared from culture media of Persicobacter sp. DH-3 and used for characterization. Relative activities at 20, 30, 40, 50, 60, and $70^{\circ}C$ were 50, 55, 70, 100, 90, and 50%, respectively. Relative activities at pH 5, 6, 7, and 8 were 75, 100, 90, and 75%, respectively. The enzyme showed maximum activity at $50^{\circ}C$ in a 20 mM Tris-HCl buffer at pH 6. This enzyme could be useful, as agar is in liquid state at $50^{\circ}C$. Agarase activities were maintained at 80% or more for 2 hr at 20, 30, and $40^{\circ}C$. Thin layer chromatography analysis suggested that Persicobacter sp. DH-3 produced extracellular ${\beta}$-agarases as it hydrolyzed agarose to produce neoagarohexaose and neoagarotetraose. In addition, zymogram analysis confirmed that Persicobacter sp. DH-3 produces at least three agar-degrading enzymes with molecular weights of 45, 70, and 140 kDa. Therefore, it is expected that agarases from Persicobacter sp. DH-3 could be used to produce functional neoagarooligosaccharides.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.329-336
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• 2021

Cellulophga sp. J9-3, is a gram-negative, aerobic marine bacterium belonging to the family Flavobacteriaceae. In addition to cellulose degradability, the J9-3 strain is also capable of hydrolyzing agar in the solid and liquid medium, and the production of agarase in the presence of agarose can be remarkably induced by the bacterium. From the cell culture broth of Cellulophga sp. J9-3, ammonium sulfate precipitation and three kinds of column chromatography were successively performed to purify a specific agarase protein, the AgaJ93. Purified AgaJ93 showed the strongest hydrolyzing activity towards agarose (approximately 22%), and even displayed activity towards starch. AgaJ93 hydrolyzed agarose into neoagarotetraose and neoagarohexaose via various oligosaccharide intermediates, indicating that AgaJ93 is an endo-type β-agarase. AgaJ93 showed maximum activity at a pH of 7.0 and temperature of 35 ℃. Its activity increased by more than six times in the presence of Co²⁺ ions. The N-terminal sequence of AgaJ93 showed 82% homology with the heat-resistant endo-type β-agarase Aga2 of Cellulophaga sp. W5C. However, the biochemical properties of the two enzymes were different. Therefore, AgaJ93 is expected to be a novel agarose, different from the previously reported β-agarases.

• Journal of Ginseng Culture
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• v.3
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• pp.119-131
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• 2021

The purpose of this study was to explore the characteristics of and solution to thermogenic reactions to Korean ginseng through bibliographic research. A review of bibliography on the thermogenic reaction induced by ginseng indicated that people who lack fluids, have fever in lungs, a stuffy chest, coughing up sputum, a strong pulse, and constipation due to fever in the stomach may exhibit such a reaction. In the herbal medicine book of the Qing Dynasty, Bon-Cho-Jeong-Ui (本草正義) recorded that wild simulated ginseng is slightly cold and replenishes the body's liquid reserves. The book also describes the field cultivated ginseng is slightly warm and enhancing stamina. Bon-Kyung-Bong-Won (本經逢源), Bon-Cho-Pyon-Dok (本草便讀), and Bon-Cho-Jeong-Ui were published authors in the Qing Dynasty, and they explained that ginseng fine root is bitter, supplements bodily fluids, and can be easily ingested because it is cold. Wol-Ji-In-Sam-Jeon (月池人蔘傳) and Bon-Cho-Bi-Yo (本草備要) described fresh ginseng assweet, bitter, and slightly cold in the Ming and Qing Dynasties, respectively. On the basis of this bibliographic description, the thermogenic reaction induced by Korean ginseng can be overcome by using ginseng fine root, fresh ginseng, or wild simulated ginseng. These ginseng radices are slightly cool, replenish human bodily fluids, and show the physiological effects of easy ingestion properties.