• Journal of Microbiology and Biotechnology
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• v.27 no.1
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• pp.155-160
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• 2017

The dye decolorization rate in a cell-free culture broth of the white-rot fungus Trametes versicolor CBR43 was studied, including the effects of inhibitors of NaCl, Zn(II), and Cd(II) on dye decolorization activity. The maximum rates of dye decolorization in cell-free culture broth were 1,410, 44.7, 41.2, and $0.19{\mu}mol{\cdot}l^{-1}{\cdot}min^{-1}$ for Acid Blue 62, Acid Black 175, Reactive Blue 4, and Acid Red 114, respectively. The inhibition effects of NaCl, Zn(II), and Cd(II) on dye decolorization were quantitatively compared using the half maximal inhibition concentration ($IC_{50}$), which indicates the concentration of an inhibitor required for 50% inhibition. Based on $IC_{50}$ values, dye decolorization in the cell-free culture broth of CBR43 was most potently inhibited by Cd(II), whereas the inhibitory effect of NaCl was relatively low. The dye decolorization rates and $IC_{50}$ data can be used in the design and development of a dye-wastewater treatment process using T. versicolor CBR43 and its operating factors.

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.759-763
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• 2000

Cell-free culture broth of Phanerochaete chrysosporium has been adopted to biologically degrade 2,4,5-trichlorophenol. Two different medium compositions of nitrogen-sufficient and nitrogen-limited were compared for their distribution of isozymes, activity of lignin peroxidase, and production of oxalate. The two different culture broths were tested for their ability to degrade 2,4,5-trichlorophenol, and the biodegradation efficiency was estimated in terms of the disappearance of 2,4,5-trichlorophenol. The degradation efficiency for the nitrogen-limited culture broth was higher than that of the nitrogen-sufficient culture broth, since the nitrogen-limited culture broth induced lignin peroxidases (LiPs) and manganese peroxidases (MnPs), and contained sufficient oxalate for producing necessary radicals. Finally, the possible mechanism of 2,4,5-CP degradation using the nitrogen-limited culture broth was proposed.

• Mycobiology
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• v.36 no.1
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• pp.13-18
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• 2008

Eight distinct bacteria were isolated form diseased mycelia of the edible mushroom, Pleurotus eryngii. 16S rDNA sequence analysis showed that the isolates belonged to a variety of bacterial genera including Bacillus (LBS5), Enterobacter (LBS1), Sphingomonas (LBS8 and LBS10), Staphylococcus (LBS3, LBS4 and LBS9) and Moraxella (LBS6). Among them, 4 bacterial isolates including LBS1, LBS4, LBS5, and LBS9 evidenced growth inhibitory activity on the mushroom mycelia. The inhibitory activity on the growth of the mushroom fruiting bodies was evaluated by the treatment of the bacterial culture broth or the heat-treated cell-free supernatant of the broth. The treatment of the culture broths or the cell-free supernatants of LBS4 or LBS9 completely inhibited the formation of the fruiting body, thereby suggesting that the inhibitory agent is a heat-stable compound. In the case of LBS5, only the bacterial cell-containing culture broth was capable of inhibiting the formation of the fruiting body, whereas the cell-free supernatant did not, which suggests that an inhibitory agent generated by LBS5 is a protein or a heat-labile chemical compound, potentially a fungal cell wall-degrading enzyme. The culture broth of LBS1 was not inhibitory. However, its cell-free supernatant was capable of inhibiting the formation of fruiting bodies. This indicates that LBS1 may produce an inhibitory heat-stable chemical compound which is readily degraded by its own secreted enzyme.

• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.448-453
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• 1997

Enzyme activities, production of killer toxin and some functionality of forty seven yeasts isolated from traditional Meju were investigated in culture broth and cell free extracts. Activities of $\alpha$-galactosidase, invertase and inulinase were detected in cell free extracts of 38 strains, 43 strains and 45 strains, respectively and acidic and neutral protease activities also were detected in culture broth of all the strains, $\beta$-Galactosidase activity was detected in cell free extracts of OE-20 and S-14 strains. Killer toxins were produced by OE-12, S-8 (Candida spp.), OE-19 (Zygosaccharomyces spp.) and S-3 (Saccharomyces spp.). Culture broth of OE-23 and S-9 showed 61.3% and 59.2% of antioxidant activity to $\alpha$, $\alpha$-diphenyl-$\beta$-picrylhydrazyl(DPPH), but nitrite-scavenging ability as well as inhibition of tyrosinase and polyphenol oxidase were not appeared in all the strains.

• KSBB Journal
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• v.14 no.2
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• pp.181-187
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• 1999

We have investigated industrial media for lactic acid fermentation to reduce the cost of nitrogen sources. Corn steep liquor (CSL) was successfully used at 5% (v/v) in batch fermentations. Use of soluble CSL improved the productivity about 20% with an advantage of clearer fermentation broth. Yeast extract-complemented CSL improved the productivity about 20% with an advantage of clearer fermentation broth. Yeast extract-complemented CSL media further increased the increased the productivity. It was found that 3.1 g/L yeast extract and 5% CSL could be an effective substitute for 15 g/L yeast extract in 10% glucose medium. Brewing yeast was also used as a sole nitrogen source equivalent to 5% CSL. A continuous culture coupled with cell-recycle by microfiltration at the dilution rate of 0.05-0.065 h-1 led to the highest lactic acid productivity. Lactic acid was recovered by electrodialysis from the cell free broth. Depleted cell free broth supplemented with 5-10 g/L of yeast extract performed reasonably in batch and continuous cultures. Reuse of the fermentation broth may reduce the cost of raw materials as well as minimize the fermentation wastes.

• Mycobiology
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• v.35 no.2
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• pp.76-81
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• 2007

Lactobacillus casei KC-324 was tested for its ability to inhibit aflatoxin production and mycelial growth of Aspergillus flavus ATCC 15517 in liquid culture. flatoxin $B_{1}$ biosynthesis and mycelial growth were inhibited in both simultaneous culture and individual antagonism assays, suggesting that the inhibitory activity was due to extracellular metabolites. produced in cell-free supernatant fluids of the cultured broth of L. casei KC-324. In cell-free supernatant fluids of all media tested, deMan, Rogosa and Sharpe broth, potato dextrose broth, and Czapek-Dox broth+1% yeast extract showed higher antiaflatoxigenic activity. In these case, fungal growths, however, was not affected as measured by mycelial dry weight. The antiaflatoxigenic metabolites from L. casei KC-324 were produced over wide range of temperatures between $25^{\circ}C$ and $37^{\circ}C$. However, these metabolites were not thermostable since the inhibitory activity of the supernatant was inactivated within 30 minutes at $100^{\circ}C$ and $121^{\circ}C$. The inhibitory activity was not influenced by changing pH of supernatant between 4 and 10. However, the antiaflatoxigenic activity was slightly reduced at pH 10.

• YAKHAK HOEJI
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• v.47 no.2
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• pp.93-97
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• 2003

Kombucha fermentation broth has been used as a popular health beverage and an alternative therapy with prophylactic and therapeutic benefit. We tried to establish optimal culture conditions for Kombucha fermentation in milk and to investigate cytotoxicity and antioxidative enzyme activity of Kombucha broth against normal human fibroblasts. The optimal conditions of Kombuch culture were established to 3$0^{\circ}C$, 20∼23 hours by DPPH radical scavenging test. There were positive effects on cell growth while no cytotoxicity against primary normal human diploid fibroblasts was found. The activites of glutathione peroxide and catalase in the cells treated by hydrogen peroxide (1 mM) alone and by hydrogen peroxide with Kombucha broth (1 mg/mι) were significantly different (p＜0.05). These results suggest that Kombucha broth could be developed as an antioxidant agent for a new cosmetic material.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.343-347
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• 2005

The polysaccharides were extracted from fruiting body, mycelia, and cell-free broth of Agaricus blazei Murill. The crude polysaccharides were obtained by the ethanol addtion. They were further purified using ion-exchange chromatography and gel chromatography. Ion-exchange chromatography using DEAE-cellulose column separated neutral and acidic polysaccharides. Neutral polysaccharides were then purified with gel filtration chromatography. For single peak obtained from gel filtration chromatography was molecular weight was measured with Sepharose CL-6B. The same procedure with acidic polysaccharides were performed to get the purified polysaccharides.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.783-788
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• 2005

To find antitumor components in liquid cultured cell-free broth and the hot water extract from the fruiting body of Hericium erinaceus, polysaccharides were purified and fractionated by DEAE-cellulose ion exchage column chromatography and Sepharose CL-6B gel filtration chromatography. Among various crude polysaccharides and purified polysaccharides the fractions showing immune-activity were determined by NO assay.

• Journal of Microbiology and Biotechnology
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• v.32 no.1
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• pp.64-71
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• 2022

The discarding of wastes into the environment is a significant problem for many communities. Still, food waste can be used for lactic acid bacteria (LAB) growth. Here, we evaluated three growth media equivalent to de Mann Rogosa Sharpe (MRS), using apple bagasse, yeast waste, fish flour, forage oats, and cheese whey. Cell-free supernatants of eight LAB strains were tested for antimicrobial activity against nine indicator microorganisms. The supernatants were also evaluated for protein content, reducing sugars, pH, and lactic acid concentration. Cell-free supernatants from fish flour broth (FFB) LAB growth were the most effective. The strain Leuconostoc mesenteroides PIM5 presented the best activity in all media. L. mesenteroides CAL14 completely inhibited L. monocytogenes and strongly inhibited Bacillus cereus (91.1%). The strain L. mesenteroides PIM5 consumed more proteins (77.42%) and reducing sugars (56.08%) in FFB than in MRS broth (51.78% and 30.58%, respectively). Culture media formulated with agroindustrial wastes positively improved the antimicrobial activity of selected LAB, probably due to the production of antimicrobial peptides or bacteriocins.