• The Korean Journal of Mycology
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• v.28 no.2
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• pp.88-92
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• 2000

Substrate improvement, maturation period and method of pinheading promotion were investigated to establish the culture method of Lyopyllum ulmarium which could obtained high yield in the short culture period. Rice bran+wheat bran (10%+10%) combination was selected from various additives, which showed vigorous growth of fruit body and high yield (133.8 g/850 cc). Oyster shells powder substance increased yield to 155.5 g per 850 cc capacity bottle. The suitable method for pinheading promotion was to stand the bottle reversely. The number of fruit bodies per 850 cc capacity bottle in this method was 27.2 stipes and bunch formation was good. When the maturation period of mycelium culture was 15 days to 30 days, pinheading period was 10 days. But when the maturing mycelium was 30 to 45 days, yield per 850 cc bottle was 148.2 g.

• Korean Journal of Microbiology
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• v.28 no.2
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• pp.162-168
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• 1990

The aims of the present study were to evaluate the effects of culture conditions on the biosynthesis of extra-cellular alkaline protease in Streptomyces sp. The formation of aerial mycelia and spores were compared with the protease production in order to know the relations between the alkaline protease and the cell differentiation. As results, it was found that substrate concentration was very critical to regulate the formation of the protease, aerial mycelia, and spores, which were resulted from the changes of culture pH to acid. When the culture pH was adjusted with phosphate buffer from pH 6 to pH 9, the alkaline protease production was increased as the culture pH increased whereas aerial mycelia and spore formation were reversely related to the culture pH. Therefore, it was thought that the culture pH was an important factor to regulate the alkaline protease synthesis.

• Mycobiology
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• v.51 no.2
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• pp.94-108
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• 2023

Termitomyces sp. that grow in symbiosis with fungus-farming Termites have medicinal properties. However, they are rare in nature, and their artificial culture is challenging. The expression of AXL receptor tyrosine kinase and immune checkpoint molecules favor the growth of cancer cells. The study evaluated the optimal conditions for the artificial culture of Termitomyces and their inhibitory activity on AXL and immune checkpoint molecules in lung adenocarcinoma and melanoma cell lines. The culture of 45 strains of Termitomyces was compared. Five strains with marked growth rates were selected. Four of the selected strains form a single cluster by sequence analysis. The mycelium of 4 selected strains produces more fungal mass in potato dextrose broth than in a mixed media. The bark was the most appropriate solid substrate for Termitomyces mycelia culture. The mycelium of all five selected strains showed a higher growth rate under normal CO₂ conditions. The culture broth, methanol, and ethyl acetate of one selected strain (T-120) inhibited the mRNA relative expression of AXL receptor tyrosine kinase and immune checkpoint molecules in cancer cell lines. Overall, these results suggest the potential usefulness of Termitomyces extracts as a coadjuvant therapy in malignant diseases.

• Journal of Korean Society on Water Environment
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• v.21 no.4
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• pp.347-352
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• 2005

The isolated microorganisms, Pseudomonas stutzeri, Raoultella planticola (Klebsiella), Serratia fonticola from petroleum contaminated soil were enriched on benzene, toluene, ethylbenzene, o-xylene as carbon and energy sources, respectively. And the degradation characteristics of BTEX was observed in the mixed BTEX substrates. We found that the BTEX in mixed substrates were degraded more than 50% by three isolated microorganisms. Among three isolated microorganisms, the highest degradation rate was observed in Pseudomonas stutzeri, but the degradation rate was different according to microorganisms. In order to increase the degradation efficiency, we applied the co-culture of isolated three microorganisms. The mixture rate of pseudomonas stutzeri : Raoultella planticola (Klebsiella) : Serratia fonticola was follows ; 1:2:1, 1:1:2, and 2:1:1, respectively. In two co-culture of 1:2:1 and 1:1:2, degradation rate was lower than isolated microorganisms. However, degradation rate became higher than isolated microorganisms and the degradation rate of benzene, toluene, and ethylene was more than 95% in co-culture of 2:1:1. The degradation rate increased through the co-culture of isolated microorganisms, however, the growth rate decreased. This was resulted from the substrate competition between microorganisms. The co-culture of microorganisms is a effective method to increase the degradation efficiency of BTEX and the co-culture mixing rate is a important factor for determination of degradation efficiency.

• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.101-105
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• 2001

Plant roots are affected by the root zone environment rather than substrate material itself. It is important to provide a suitable environment for the roots by amending the substrate and adjusting supply of the nutrient solution. In an expanded rice hull substrates, 1.5 L nutrient solution was supplied on each day at different frequency. In rice hull substrate, plant growth and yield were the greatest in the treatment where a 1.5L nutrient solution was supplied as 24 equal aliquots, wheres in perlite substrate plant growth and yield were the greatest in the treatment with 16 aliquots. Nitrogen deficiency symptoms caused by early decomposition of rice hulls by microorganisms was recovered by increasing solution EC from 1.7 to EC 2.0 dS.m$^{-1}$ for 25 days after planting. Plant growth and yield increased in the treatment of Ec 3.0 dS.m$^{-1}$ , but the cause for this increase is not clear.

• Journal of the Optical Society of Korea
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• v.18 no.2
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• pp.174-179
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• 2014

Since in vitro neural recording and imaging applications based on a surface plasmon resonance (SPR) technique have expanded dramatically in recent years, cytotoxicity assessment to ensure the biosafety and biocompatibility for those applications is crucial. Here, we report the cytotoxicity of the SPR substrate incorporating a flint glass whose refractive index is larger than that of a conventional crown glass. A high refractive index glass substrate is essential in neural signal detection due to the advantages such as high sensitivity and wide dynamic range. From experimental data using primary hippocampal neurons, it is found that a lead-based flint glass is not appropriate as a neural recording template although the neuron cells are not directly attached to the toxic glass. We also demonstrate that the adhesion layer between the glass substrate and the gold film plays an important role in achieving the substrate stability and the cell viability.

• Journal of Applied Biological Chemistry
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• v.59 no.4
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• pp.289-298
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• 2016

FK506 hyper-yielding mutant, called the TCM8594 strain, was made from Streptomyces tsukubaensis NRRL 18488 by mutagenesis using N-methyl-N'-nitro-N-nitrosoguanidine, ultraviolet irradiation, and FK506 sequential resistance selection. FK506 production by the TCM8594 strain improved 45.1-fold ($505.4{\mu}g/mL$) compared to that of S. tsukubaensis NRRL 18488 ($11.2{\mu}g/mL$). Among the five substrates, wheat bran was selected as the best solid substrate to produce optimum quantities of FK506 ($382.7{\mu}g/g$ substrate) under solid-state fermentation, and the process parameters affecting FK506 production were optimized. Maximum FK506 yield ($897.4{\mu}g/g$ substrate) was achieved by optimizing process parameters, such as wheat bran with 5 % (w/w) dextrin and yeast extract as additional nutrients, 70 % (v/w) initial solid substrate moisture content, initial medium pH of 7.2, $30^{\circ}C$ incubation temperature, inoculum level that was 10 % (v/w) of the cell mass equivalent, and a 10 day incubation. The results showed an overall 234 % increase in FK506 production after optimizing the process parameters.

• The Korean Journal of Mycology
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• v.27 no.4 s.91
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• pp.304-311
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• 1999

Batch kinetics during the exo-polysaccharide (EPS) fermentation of Ganoderma lucidum was investigated as a function of different substrates (glucose and starch), substrate concentration $(1{\sim}7%,\;w/v)$ and subculture (3 times). Logistic model for mycelial growth fitted the experimental data better than Monod and two thirds power model. The Luedeking-Pirt equation was adequate to fit the kinetic data of product formation and substrate consumption. The EPS production was strongly non-growth associated, although it was mixed type. The product formation and sustrate consumption by growth associated mechanism decreased as the concentration of glucose increased, while those of the non-growth associated mechanism increased. However, starch medium increased the growth associated and non-growth associated substrate consumption indicating higher availability of substrate. Also, batch culture in starch medium showed the higher specific growth rate and stability during subculture than those in glucose medium. In conclusion, the enhanced EPS production and stability in the subculture was found to be remarkably improved by use of starch as sole carbon source in medium. The maximum mycelium dry weight and EPS production of 9.463 and 10.410 g/l, respectively, were obtained after shake culture of 7 days at $30^{\circ}C$ from the media containing 7% starch.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.440-444
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• 2003

A new approach for ground water treatment combines a permeable Fe(0) barrier to breakdown higher chlorinated solvents like PCE and TCE with a down gradient aerobic biological treatment system to biotransform less chlorinated solvents, such as DCE and vinyl chloride (VC). The expected bacterial performance down gradient of an Fe(0) barrier was evaluated through laboratory batch experiments with a toluene-degrading mixed culture that cometabolically transforms cis-1,2-DCE and VC. The amount of cis-1,2-DCE (initially at 2,000 ppb) and VC (initially at 2,000 ppb) transformed was controlled by the initial toluene(20,000 ppb) concentration. VC was removed much more effectively than Cis-1,2-DCE, and a higher toluene concentration in comparison to the co-substrate concentrations was needed for complete co-substrate removal. Overall, the coupling of an Fe(0) barrier and subsequent biodegradation appears feasible for remediation of complex mixtures of chlorinated solvents and petroleum hydrocarbons in groundwater.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.2
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• pp.169-173
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• 1999

Studies were made to evaluate the specific and combined effects of different fatty acids on the in vitro development of 8-cell rat embryo in culture media with and without carbohydrate substrate. Palmitic, oleic, linoleic and arachidonic acids were added singly and in combination to media which contained fatty acid-free BSA. Cell numbers in blastocysts cultured in the media were counted and compared with cell numbers in blastocysts at the corresponding stage collected from the uterus. Oleic, linoleic and arachidonic acids promoted the rat embryo development from 8-cell to the blastocysts. especially in the absence of carbohydrate substrates. Among these three, oleic acid was the most effective but embryo development was not accelerated by the addition of palmitic acid in either the presence or the absence of carbohydrate substrates. Addition of the mixture of four fatty acids was more effective for rat embryo development than single treatment with any of fatty acids tested. Cell numbers per blastocyst in the presence and absence of carbohydrate substrate were similar, and did not differ from those for blastocysts obtained from the uterus.