• Mycobiology
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• v.28 no.4
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• pp.197-201
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• 2000

The distribution and occurrence of aquatic zoosporic and terrestrial fungi were investigated in 21 well waters in Assiut governorate, Egypt. Using a zoospore capture technique, 923 colonies of aquatic freshwater fungi were recovered from well waters, out of which 811 colonies reached sexual maturity. These colonies were assigned to 23 species which belong to 11 genera. The most common genera were Achlya, Saprolegnia and Dictyuchus. Using two types of media, 35 species in addition to 2 varieties of terrestrial fungi which belong to 18 genera were also recovered. The most frequent glucophilic genera (recovered on glucose-Czapek's agar at $28^{\circ}C$) were Aspergillus, Penicillium and Fusarium. The results obtained on cellulose-Czapek's agar at $2^{\circ}C$ were basically similar to those on glucose agar and the most frequent genera were Aspergillus, Penicillium and Fusarium followed by Chaetomium and Cephalosporium.

• Journal of Mushroom
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• v.14 no.1
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• pp.6-13
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• 2016

This study was carried out to determine the basic mycelial culture conditions for Poria cocos growth. According to colony diameter and mycelial density, suitable media for mycelial growth were Malt yeast extract, Potato dextrose agar, Yeast extract agar, and Yeast malt agar. The optimum temperature for mycelial growth was between 25 and $35^{\circ}C$, and the optimum pH value was between 4 and 7. Carbon and nitrogen sources were fructose and yeast extract. The optimum C/N ratio was about 10 to 1 with 2% glucose. Other minor components for optimal growth were thiamine-HCl and nicotinamide as vitamins, acetic and lactic acid as organic acids, and $MgSO_4{\cdot}7H_2O$ and $FeSO_4{\cdot}7H_2O$ as mineral salts.

• Korean Journal of Pharmacognosy
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• v.15 no.1
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• pp.39-42
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• 1984

To examine stability and a separate quantitative method of a mixed preparation of lactic acid bacteria, a capsule containing Lactobacillus acidophilus, Lactobacillus bulgaricus and Streptococcus thermophilus was suspended and diluted in sterile water. After the diluted suspension was spread on three media of tryptone glucose extract agar, MRS agar and MRS-sucrose agar, their colonies appeared and were counted. The viable counts exceeded the minimum number of the three bacteria and showed that the mixed preparation was stable at least for 18 months. The results also showed that a separate quantitation of viable cells of the each strain was feasible.

• Journal of Food Hygiene and Safety
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• v.27 no.2
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• pp.169-175
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• 2012

Five kinds of selective media, such as mannitol salt agar (MSA), Baird-Parker agar (BPA), Baird-Parker supplemented with rabbit plasma fibrinogen (BPA+RPF), CHROMagar Staphylococcus aureus (CSA), and Petrifilm Staph Express count system (Petrifilm), were compared to recommend the optimum selective media for isolation of Staphylococcus aureus from agricultural products. Seventy four target and non target bacteria were inoculated on five selective media to analyze sensitivity and specificity. In the recovery test of injured S. aureus cells, S. aureus was exposed to acid (1% lactic acid for 10 min), heat ($60^{\circ}C$ for 90s), and cold ($-20^{\circ}C$ for 1h) conditions. And artificially contaminated agricultural products (iceberg lettuce, green pepper, and cherry tomato) was enumerated on five selective media. The sensitivity of BPA+RPF, CSA, Petrifilm, MSA, and BPA were 100%, 100%, 100%, 90.5%, 90.5%, respectively. In addition, the specificity of BPA+RPF, CSA, MSA, BPA and Petrifilm were 100%, 100%, 84.6%, 75.0%, 67.3%, respectively. However, no difference among five selective media was observed in recovery on injured S. aureus cell and enumeration from agricultural products. This results suggest that BPA+RPF and CSA are the optimum media for detection of S. aureus from agricultural products.

• Journal of Mushroom
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• v.11 no.3
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• pp.124-130
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• 2013

The effects of environmental and nutritional requirement such as temperature, pH, different media, carbon, nitrogen, and carbon-to-nitrogen ratio on the mycelial growth of Cordyceps militaris strain 'Yedang 3' were studied. The optimum temperature and pH for the growth of mycelium were $20-25^{\circ}C$ and pH 6-7, respectively. Out of ten media tested, mushroom complete media (MCM) was the best medium for fast mycelial growth, and Sabouraud's dextrose agar yeast extract (SDAY), malt extract yeast extract agar (YMA) also were favored. The color and shape of colonies varied in different media. The best carbon sources for mycelial growth were fructose, mannitol, and sucrose, whereas the best nitrogen sources were tryptone and peptone. However, mycelia grew slowly in inorganic nitrogen compounds such as $NH_4Cl$, $(NH_4)_2SO_4$, $NH_4NO_3$, and $NaNO_3$. The optimum C:N ratio observed on the culture media was 30-40 range. These results provided basic information on cultural characteristics of vegetative growth and might be useful for spawn production in Cordyceps militaris.

• Korean Journal of Microbiology
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• v.18 no.3
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• pp.148-152
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• 1980

The microwave of 2450 MHz, generated by a household cooking oven, was evaluated for its applicability to melt various rehydrated media and to remove dissolved oxygen from tubed media for anaerobic culture. The effect on the sterilization of E. coli in selective media was also evaluated. The following results were obtained. 10 The microwave oven was useful in saving time for melting media and in eliminating heat and combustion gas from the laboratory, which were inevitable by-products in the conventional flame method. 2) Dissolved oxygen could be removed without boiling over by exposing the tubes of anaerobic culture medium after putting them in a wire basket in a beaker with water. 30 The count of E. coli during the melting of MacConkey and EMB agar were similar to those treated with open flame. The microwave treatment was not considered a possible mean to replace autoclaving even in these selective media.

• Journal of Applied Biological Chemistry
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• v.50 no.2
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• pp.41-45
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• 2007

Polaromonas naphthalenivorans CJ2, responsible for naphthalene degradation at a coal tar contaminated site, was isolated on MSB agar media supplied with naphthalene vapor as the sole carbon source at $10^{\circ}C$. The strain is not isolated under the same isolation condition using the same soil sediment at $20^{\circ}C$ although its optimum temperature is about $20^{\circ}C$. In this work we explored the reason why strain CJ2 could not have been isolated on MSB agar with naphthalene vapor at $20^{\circ}C$. Dispersed CJ2 cells in PBS buffer formed colonies on MSB agar with naphthalene vapor at $10^{\circ}C$ with low naphthalene vapor pressure, but not at $20^{\circ}C$ with high naphthalene vapor pressure. However, streaked cells without resuspension grew on MSB agar with naphthalene vapor at $10^{\circ}C,\;20^{\circ}C$, and even $25^{\circ}C$. Investigation of scanning electron microscopy showed that CJ2 cells formed extracellular polysaccharide (EPS) capsules, which were released easily from CJ2 cells by just dispersion. Therefore, it is concluded that strain CJ2 is able to overcome the naphthalene toxicity by forming a capsule-type barrier around the cells although it is susceptible to naphthalene toxicity at high temperature.

• The Korean Journal of Mycology
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• v.51 no.2
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• pp.101-109
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• 2023

A fungal strain designated KNUF-21-66Q1 was isolated from soil in Chungcheongbuk Province, Korea. Moderate growth of colonies was observed on potato dextrose agar, oatmeal agar (OA), malt extract agar, and cornmeal agar media at 25℃, and the detailed morphology was examined on OA medium. The colonies on OA medium were flat, had entire margin, hyaline, and yellow concentric rings in 3-4 weeks. Conidiomata were pycnidial, solitary or clustered, globose to subglobose, black-brown, and 300-500 ㎛ in diameter. Conidiogenous cells were smooth, hyaline, globose to ampulliform, and 6.0-9.0×3.0-6.0 ㎛ in size (n=15). Conidia were hyaline to pale brown, slightly golden, obovoid to slightly ellipsoidal, smooth, guttulate, and 3.0-4.7×2.1-3.3 ㎛ in size (n=100). The strain was confirmed based on phylogenetic analysis using internal transcribed spacer regions, the partial 28S rDNA of large subunit, and β-tubulin gene sequences. The morphological observations and phylogenetic analysis revealed that the strain KNUF-21-66Q1 was similar to the previously described Paraconiothyrium kelleni. To our knowledge, this is the first report of P. kelleni in Korea.

• Journal of agriculture & life science
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• v.44 no.3
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• pp.23-30
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• 2010

The optimal growth condition of in vitro stem cutting of Dendrobium nobile 'Hamana Lake Dream' ${\times}$ 'No. 55' was investigated. Among various media and their concentrations, MS media had better effect on the growth of micro stem cutting than Hyponex media in all concentration levels except stem length. The activated charcoal concentration in MS media showed different effects on number of stem and root, leaf length, and fresh weight: the most effective in the range of 0.1 to 1.0 g/L and barely effective above 2.0 g/L. Addition of agar 5 g/L, sucrose at 40 g/L, and peptone at 1 g/L to MS media increased significantly stem length, leaf width, and fresh weight, internode length and number of roots, and the number of stem and leaves. On the other hand, addition of gelite with any concentration had no effect on the growth of micro stem cutting compare to that of control. The optimal temperature for growth of micro stem cutting was $28^{\circ}C$. Under the same temperature, MS medium was better than Hyponex medium for the growth of stem. In addition, sucrose at 40 g/L was the most effective on growth at $28^{\circ}C$.

• KSBB Journal
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• v.22 no.4
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• pp.239-243
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• 2007

A method of forming agar microcapsule with fibroin coating was developed in this report. The capsules were prepared from a W/O emulsion of hot agar in mineral oil and were subsequently coated by fibroin. The capsules were harvested as precipitated aggregates, which can be dispersed in an aqueous media. The diameter of the microcapsule was less than $10{\mu}m$ by microscopic observation and 90% of them were between $1.32{\mu}m\;and\;6.0{\mu}m$. The structure of the aggregates and their dispersed microspheres were investigated by scanning electron microscope. Confocal microscopy was applied to visualize the core-shell structure of the agar microcapsule with fibroin coating. Thermogravimetric analysis (TGA) measured their composition to be agar 51.2%, fibroin 13.8%, Span 80 1.4% by weight.