• Journal of Food Hygiene and Safety
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• v.14 no.3
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• pp.270-276
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• 1999

In previous reports, the authors isolated the algicidal marine bacterium, Alteromonas sp. SR-14 and demonstrated its growth inhibition of diatom, Chaetoceros calcitrans (C. calcitrans). In this paper, we studied the effects of cell free culture filtrate of Alteromonas sp. SR-14 on the growth of C. calcitrans, and the characteristics of the algal growth inhibition substance. The culture filtrate of Alteromonas sp. SR-14 grown in peptone broth showed growth inhibition activity against C. calcitrans. The reasonable culture conditions of the bacterium for producing of algal growth inhibition substances were $15~20^{\circ}$ in temperature, 7.0-9.0 in pH and $23~30{\textperthousand}$ in salinity, respectively. The algal growth inhibition activity of culture filtrate was increased from stationary phase in growth curve of Alteromonas sp. SR-14. The molecular weights of algal growth inhibition substances produced by Alteromonas sp. SR-14 were ranged about from 3 KDa to 12 KDa. Among the substances, less than 10 KDa fraction were stable by heating at $100^{\circ}$ for 10 minutes, while more than 10 KDa fraction were heat labile. According to the experimental results, the algal growth inhibition substance produced by the bacterium was not a single compound.

• Journal of the Korean Wood Science and Technology
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• v.28 no.1
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• pp.48-54
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• 2000

The effects of thiamin on vegetative mycelial growth and fruit body formation of Lentinuia edodes were investigated in basal peptone-glucose liquid medium in relation to the uptake of thiamin. Thiamin was essential for fruit body formation, and the minimum requirements for thiamin were estimated to be approximately 10 ${\mu}g$/L. The vegetative mycelial growth was little influenced by the addition of thiamin in the range of 1.5 ${\mu}g$~1.5 mg/L. While the mycelium was successively transferred to fresh peptone-glucose-agar medium three times, the repression of mycelial growth was not significant. Even in cases using vitamin-free casamino acid or glutamic acid as a nitrogen source instead of peptone, a thiamin deficiency for mycelial growth did not occur as a result of transferring the mycelia to fresh media. Almost all of the thiamin contained in the media accumulated in the mycelia during the first 3 weeks of a 9-week incubation. These results suggest that only trace amounts of thiamin are required for vegetative mycelial growth in Lentinula edodes and that almost all thiamin added to a basal medium will be used for fruit body formation.

• Korean Journal of Microbiology
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• v.51 no.1
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• pp.75-80
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• 2015

Pseudoalteromonas donghaensis HJ51, isolated from the East Sea, has been reported as a novel strain to produce extracellular protease. Crude supernatant was used to determine optimal activity and optimal production conditions for the enzyme. It was found that the optimal temperature and pH of the protease were $40^{\circ}C$ and pH 7.5-10.5, respectively. The enzyme activity was kept to 88% at the pH 11. In metal requirement analysis, the enzyme exhibited the highest activity when 10 mM $Fe^{3+}$ was supplied. While supplementation of additional carbon sources used in study showed no positive effect on cell growth and enzyme activity, the addition of beef extract, tryptone, or casamino acids instead of peptone of PY-ASW containing 1% glucose increased enzyme production to 21, 7, 4%, respectively. Taken together these properties, the enzyme produced from P. donghaensis HJ51 can be applied to the industries that require protease activity under alkaline pH and low temperature.

• Applied Biological Chemistry
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• v.43 no.3
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• pp.202-206
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• 2000

Feasibility of microbial culture media using by-product of salt fermented kanary was investigated. Gram negative strain, Escherichia coli, and Gram positive strain, Bacillus subtilis, and bioluminescent Photobacterium Phosphoreum were incubated with kanary by-Product media (KB media). Compared with LB media, KB media had enough carbon source, but lacked nitrogen source and growth factor. When 0.5% of peptone as a nitrogen source and 0.3% of yeast extract as nitrogen and growth factor source were fortified in KB media, the cell population rate was similar to LB media. Also, when 0.5% of yeast extract was fortified to KB media, it showed the same result as in LB media. The price of KB media with fortification of 0.5% peptone and 0.3% yeast extract, and 0.5% of yeast extract is only 46 and 19% of that of LB media, respectively. These results showed that kanary by-Product could be a good and cheaper bacterial culture media if small amount of nitrogen source and growth factor were added.

• Journal of Mushroom
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• v.18 no.4
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• pp.365-371
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• 2020

In this study, we analyzed the effect of media on the production of carotenoids and mycelia by using Perenniporia fraxinea. Malt extract-based medium with less than 0.1% peptone stimulated the production of carotenoids, and the one with more than 0.2% peptone inhibited its production. P. fraxinea grown in medium without malt extract did not produce carotenoids, although a small amount of peptone was added to the medium.After carotenoid production, the culture broth was separated using simple centrifugation and the supernatant was harvested as a carotenoid solution. Ethanol was used to extract carotenoids from mycelia. Carotenoid solution separated or extracted from the culture solution showed DPPH radical scavenging activity. The antioxidant carotenoids produced by P. fraxinea are derived from natural products, have no toxicity and side effects, and exhibit excellent antioxidant effects; therefore, they can be effectively used to remove oxides produced by active oxygen.

• The Korean Journal of Mycology
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• v.14 no.2
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• pp.121-130
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• 1986

Factors affecting the productivity of cellulolytic enzymes and the mycelial growth of Ganoderma lucidum CAFM 9065 were examined in synthetic media. Among the carbon sources tested, Na-CMC was the best for the production of avicelase CMC ase, and cellobiose for ${\beta}-glucosidase$. Soluble starch and cellobiose were the best for the mycelial growth. The optimum concentration of Na-CMC for the production of the enzymes was 1.0 %, and mycelial growth increased remarkably with the higher concentration of Na-CMC. Glucose inhibited the production of the enzymes, but stimulated the mycelial growth. Among the nitrogen sources used, peptone was the most effective for the production of the enzymes, and the appropriate concentration of peptone was 0.2%. The mycelial growth was stimulated with the increase of the concentration of peptone up to 0.5%. The optimum concentration of $KH_2PO_4$ for the production of the enzymes and mycelial growth was 0.3 and 0.2%, respectively. The optimum concentration of $MgSO_4{\cdot}7H_2O$ for the production of the enzymes and mycelial growth was 0.02%. The production of the enzymes was facilitated by folic acid at a low concentration (0.03 mg/l), and mycelial growth by inositol. The optimum temperature for the production of the enzymes and mycelial growth was $30^{\circ}C$. The optimum pH for the production of avicelase and ${\beta}-glucosidase$ was 5.0 equally and CMCase 5.5. The activities of avicelase and CMCase were the highest at 8 and 10 days of culture, respectively and that of ${\beta}-glucosidase$ at 16 day culture. The growth of mycelium was the highest at 12 days of culture at pH 5.0.

• Journal of Life Science
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• v.26 no.5
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• pp.571-583
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• 2016

Biogenic amines are produced primarily by microorganisms found in fermented foods and are often implicated in poisoning incidents in humans. In this study, 620 strains of microorganisms were isolated from traditional Korean fermented food in Sunchang in order to screen for non-biogenicamine-producing microorganisms present in these foods. One strain was identified and named Bacillus subtilis SCJ1, by using 16S rRNA sequencing and biochemical characterization. We investigated the cell growth of this organism in order to understand its potential for industrial application. To this end, we optimized the culture medium constituents by using the response surface methodology. The Plackett-Burman experimental design was used for screening of the medium constituents, such as molasses, yeast extract and peptone, for improving cell growth. In order to determine the optimal concentration of each constituent, we used a central composite design. Consequently, the optimized concentrations of molasses, yeast extract and peptone were predicted to be 27.5 g/l, 7.5 g/l and 17.5 g/l, respectively. By model verification, we confirmed that a 1.49-fold increase in dry cell weight compared to the basal medium-from 1.32 g/l, to 1.9722 g/l-was achieved.

• Korean Journal of Microbiology
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• v.31 no.2
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• pp.105-112
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• 1993

Plesiomonas shigelloides distributed in the aquatic systems was isolated and identified in this study and compared with the c1inica] isolates in view of their physiological characteristics, Biochemica] charactristics of the isolates of P. shigelloides one sample taken from Gupo and two samples taken from Mu]gum, were studied. However, none was isolated in Haeundae, Dadaepo, Kangdong and Nakdong estuary. The isolated bacteria had an optimum growth condition in peptone water of $25~35^{\circ}C$, pH 7.5-8.0 and 1% NaCI concentration. The cell grew most properly on the selective enrichment media which were made from adding inositol to peptone water. DNase was s]owly produced and the results were different from those of other studies. The components of the fatty acid were 3% of 3-hydroxy]ated fatty acid containing $C_{12}~C_{18}$. 0-10% cyclopropane ($C_{17:0}$), 25~30% hexadecanoic acid ($C_{16:0}$), 32~43% hexadecenoic acid ($C_{16:1}$), 1~2% octadecanoic acid ($C_{16:0}$), and 9~14% octadecenoic acid ($C_{18:1}$). Bacterio]ogica] characteristics, susceptibility of antibiotics, and the components of fatty acid of the c1inica] isolates were similar to those of the strains isolated from the aquatic systems. The strains isolated from c1inica] sources degraded lactose more fast than those isolated from the aquatic systems. There existed resistant bacteria to chlorampenicol in the strains from patients, but there were no resistant bacteria in the strains from the aquatic systems. The components of fatty acid of the clinical isolates were 0~2% $C_{17:0 cyclo}$ and 2~3% $C_{18:0}$, but those of the strains from the aquatic systems were 2~10% and 1~2%, respectvely, which showed the quantitative difference between both components.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.100-103
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• 2004

The culture condition and medium composition for the enhanced mycelial growth of Inonotus mikadoi IMSNU 32058 were investigated. The optimal temperature and pH for the mycelial growth were $27^{\circ}C$ and pH 4.5, respectively. Among the complex media tested, the malt extract medium and Phellinus igniarius medium were very good for mycelial growth of I. mikadoi. When Czapek-Dox medium was used as a minimal medium for cultivation of mycelia, xylose, raffinose and carboxymethyl cellulose were very excellent as a carbon and energy source. With respect to carbohydrate, sucrose and glucose were very good carbon sources. In general, organic complex nitrogen sources were better than other inorganic ones. As the organic complex nitrogen sources tested, yeast extract, soytone, proteose peptone and bacto peptone were the best as a source of organic nitrogen. When ammonium sulfate as an inorganic source of nitrogen was used, the enhanced mycelial growth was shown. p-Aminobenzoic acid was proved to be most appropriate source of vitamin. After the mycelia of I. mikadoi was cultivated at $27^{\circ}C$ for 5 days in MEM broth (pH 4.5), the activities of both exomycelial and endo-mycelial enzymes were determined. Among endomycelial enzymes assayed, the specific activity of laccase was much higher than those of other enzymes. When the fungus was grown in MEM broth, exomycelial specific enzyme activity of laccase was comparatively high. However, little or no enzyme activities of protease, chitinase and lipase were found.

• Microbiology and Biotechnology Letters
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• v.37 no.1
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• pp.62-68
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• 2009

The culture conditions to maximize the production of laccase (EC 1.10.3.2) from Fomitopsis pinicola mycelia were investigated. Among the tested media for the enzyme production, mushroom complete medium (MCM ; 2% dextrose, 0.2% peptone, 0.2% yeast extract, 0.05% $KH_2PO_4$, and 0.05% $MgSO_4{\cdot}7H_2O$) showed the highest activity of the enzyme. To optimize the culture condition for the laccase activity, influence of various carbon and nitrogen sources was investigated in MCM. Among various carbon and nitrogen sources, 2% glucose and 0.4% peptone showed the highest production of the enzyme, respectively. For the phosphorus and inorganic source, 0.05% $NaH_2PO_4$ and 0.05% $CaCl_2$ were best for the enzyme activity. The enzyme production was reached to highest level after the cultivation for 8 days at $25^{\circ}C$. Native polyacrylamide gel electrophoresis (PAGE) followed by the laccase activity staining using 2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as the substrate was performed to identify the laccase under culture conditions studied. Zymogram analysis of the culture supernatant showed a laccase band with molecular mass of 52 kDa. The optimum pH and temperature for the enzyme activity were $80^{\circ}C$ and pH 3.0.