• Mycobiology
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• v.38 no.3
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• pp.189-194
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• 2010

This study investigated the cultural characteristics of Shimizuomyces paradoxus in different nutritional and environmental conditions. The highest mycelial growth was observed in Schizophyllum (mushroom) genetics complete medium plus yeast extract agar medium, and the optimal temperature and pH were $25^{\circ}C$ and pH 8.0, respectively. The optimal carbon and nitrogen sources were 1% dextrose and 1% peptone in agar. However, in liquid culture the highest dry mycelium weight was found for the potato dextrose agar and potato sucrose agar broths. The optimum inoculum size was five mycelial discs (5 mm) per 100 mL of broth, and the optimum liquid culture period was 25 days. This is the first ever report of S. paradoxus cultural characteristics.

• ALGAE
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• v.20 no.1
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• pp.61-67
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• 2005

Agar was extracted from Gelidium amansii, which was harvested at the shores of Jeju Island in South Korea. As a unique solvent, the ability of dimethyl sulfoxide (DMSO) was used to separate agarose from agar by removing agaropectine and quality of the resultant agarose was characterized for chromatography purposes. Agar sample was agitated by motor-driven stirrer with DMSO in a water bath (at 70$^{\circ}C$ for 2 h) and centrifuged (3,000 rpm for 20 min). Resultant upper agarose layer was gelled, washed, dried and milled. The quality of agarose was evaluated by the analysis of proximate chemical composition, sulfate content, gelling strength and DNA migration. In this study, the separated agarose showed low sulfate amount (0.28%) and showed high gel strength (1190 g ${\cdot}\;cm^{-2}$). The resolution power and the ligase activities gave clear picture about the suitability of the present agarose for practical purposes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.927-935
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• 1997

This study was conducted to investigate the effect of nondigestable substances and calcium such as oligosaccharide, agar, saponin, tannin and calcium on the reduction of lipid status in rats fed high fat diet. In order to make the observation, the lipid content in plasma, liver and the feces, and bile acid excretion were measured of r 4 weeks. the results obtained from this research are as follows. Concentration of total lipid in plasma seemed highest in the control group and were significantly lower in groups oil-gosaccharide, agar and calcium-tannin, compared to the control group. Concentration of total cholesterol in plasma was significantly lower in groups oligosaccharide, agar, calcium and calcium-saponin, compared to the control group. The improvement in lipid status seems to be insignificant with oligosaccharide, showed increase in total bile acids excretion in feces and decrease in total cholesterol in plasma, compared to the control group. These evidence seems to indicate improvement of the plasma lipid status by calcium and agar supplementation.

• Journal of Microbiology
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• v.34 no.4
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• pp.384-386
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• 1996

Application of polyacrylamide gel (PAG) instead of agar to solid cultures of Streptomyces spp. was studied. The improved media were prepared by 1) gelling 20 ml of 5% acrylamide in a glass petri dish at room temperature, 2) washing by running water for more than 8 hr to remove residual reaction reagents, 3) drying at 5$0^{\circ}C$ for 12 hr to make a gel film, 4) autoclaving at 121$^{\circ}C$ for 15 min, and 5) swelling gel for about 4 hr by adding sterile liquid medium. In PAG media there were no differences from the observation of morphological characteristics showing during the cellular differentiation on agar media, whereas the ability to utilize carbohydrates differed somewhat from agar media. Agar media thus were little favorable for biochemical tests which the growth was determined depending on the formation of colony, but washed PAG was superior to serve as a solidifying agent.

• Microbiology and Biotechnology Letters
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• v.21 no.3
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• pp.288-292
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• 1993

An agar medium(HY) was developed to detect the urease-producing lactic acid bacteria. HY medium was prepared with the addition of tryptone, glucose and tween 80 to the supernatant of autoclaved skim milk and yeast extract mixture. There was no difference in eumeration of lactic acid bacteria between the HY and commercial media, such as M17, MRS and BCP agar. The urease activity of Streptococcus salivarius subsp. thermophilus was detected on the HY agar medium contained urea by the color change of bromocresol purple as the pH indicator, but not on the commerical agar media. Furthermore, it was succeeded to screen the urease activity of bacteria in skim milk used as a raw material in dairy product manufacture. Therefore, HY medium was proved to be suitable for the screening of urease-producing lactic acid bacteria.

• The Korean Journal of Mycology
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• v.42 no.1
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• pp.40-49
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• 2014

The mycelial growths of wood-decaying mushroom strains collected from Korean forests were investigated on solid media under different culture media and temperatures. Most of strains showed the higher mycelial growth on potato dextrose agar (PDA) than malt extract agar (MEA) or sabouraud dextrose agar (SDA) plates. Except for a few strains, they grew well on PDA at $25^{\circ}C$ and showed a poor growth at low temperature ($10^{\circ}C$) than high temperature ($30^{\circ}C$). All strains showed the carboxymethylcellulase (CM-cellulase) and laccase activities on solid media containing the specific substrates for two different enzymes.

• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1320-1324
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• 2006

The pancreatic and neutrophil elastases are associated with several illnesses including lung and vascular diseases, various cancers, and pancreatitis. The development of a potent and specific inhibitor to the elastases could lead to new therapies. In this study, an agar diffusion method was modified to include a substrate-dye conjugate (Elastin-Congo red) as a substrate of elastase and an indicator of elastase inhibitory activity. The Elastin-Congo red agar plates consisted of 0.1 % Elastin-Congo red and 2.5% agar. The elastase and elastase inhibitors were simultaneously loaded into wells, ultimately resulting in halo formations in which the halo diameter decreased as the concentration of elastase inhibitor increased. The concentration of elastase inhibitor in the samples, therefore, was inversely proportional to the halo diameters. This simplified method provided an excellent correlation with the standard microplate technique, which uses a chromogenic substrate. The concentration of elastase inhibitor obtained from the culture supernatant of a recombinant elastase inhibitor produced by the yeast Pichia pastoris was easily determined. This study has established a simple modified and inexpensive agar diffusion method that is potentially useful for the identification, quantification, and screening of new elastase inhibitors.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.183-186
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• 2007

The type of mixed gel network of $\kappa$-carrageenan/agar was determined by applying rheological principles. Apparent Young's modulus of the mixed gels was mathematically analyzed with (a) simply adding the moduli of two component gels, (b) phase-separated type's upper and lower bound models, (c) interpenetrating type's logarithmic model. The experimental data fitted the estimates from the operation (a). Whereas, as for the models (b), the experimental values in the agar-rich region fitted the estimates of the upper bound model, but in the $\kappa$-carrageenan-rich region slightly deviated from those of the lower bound model. It reflected an evidence of a phase-separated type, although it was not typical, that there must be data good-fit in the agar-rich and $\kappa$-carrageenan-rich regions with the upper and lower bound models, respectively. Experimental values disagreed with estimates of the model (c). Gel time was analyzed to evince the phase-separated type. As agar concentrations increased at a fixed amount of $\kappa$-carrageenan, gel time gradually decreased and then sharply increased and decreased again. The pattern of such change in gel time also represented a typical behavior of phase-separated type's mixed gels.

• The Journal of the Korean Society for Microbiology
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• v.19 no.1
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• pp.73-77
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• 1984

Vibrio vulnificus is an organism capable of causing septicemia and wound infection in compromised patients. The source of infection is known to be raw oysters and others. The prevalence of the organism in Korean sea water and shellfish is not known. The authors surveyed shellfish and other specimens obtained mainly from a market in Seoul and from ones in Inchon. Five cultures of V. vulnificus were isolated from oyster and clam samples. Two isolates had typical characteristics of the strains isolated from patients, i.e., definite hemolysis and typical biochemical reactions. However, other 2 isolates were sucrose positive, although the identity were confirmed by Center for Disease Control. We do not know wether such strains are pathogenic or not. For the isolation of V. vulnificus from environmental samples, TCBS agar and VV agar were not very selective or differential. We isolated our strains with the use of OF-lactose agar and SPS agar. However OF-lactose agar did not support good growth of V. vulnificus, while SPS agar did not suppress other vibrios.

• The Korean Journal of Community Living Science
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• v.16 no.2
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• pp.17-26
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• 2005

This study was conducted to investigate the usefulness of a hot water extract of licorice root as a source for production of healthy food. The electron donating capacity of the hot water extract of licorice root was very strong. This activity decreased by $6.9\%$ after keeping it in 5 days of cold storage, but it was not significantly different. Ten types of licorice jellies were prepared, using agar, agar-pectin, agar-cellulose, 2 different proportions of agar-pectin-cellulose as a gelling agent, and 2 levels of sugar. Among the 5 jellies containing $10\%$ sugar, the elasticity and overall acceptance of the agar jelly obtained the highest sensory score, but the color and flavor were not affected by the type of gelling agents. As the sugar concentration increased to $15\%$, the elasticity of the agar jelly was also evaluated as being the best one among the 5 jellies, but the overall acceptance was not significantly different from the others.