• Journal of Ginseng Research
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• v.27 no.4
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• pp.195-201
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• 2003

Chlamydospore formation from mycelia and conidia of Cylindrocarpon destructans isolated from the root rot lesion of the Panax ginseng was investigated by scanning electron and light microscopy. Typical chlamydospores were formed only from hyphae but not from conidia on culture media. However, immature chlamydopspore-like cells were formed from microconidia after 12 days of incubation at 20$^{\circ}C$ on Czapek Dox broth (CDB) adjusted to pH 4.0. Chlamydospores were yellowish or reddish brown in color, and produced singly or in chain with the hyphal intercalary or terminal position on potato-dextrose agar, V-8 juice agar and CDB with no addition of nitrogen sources after 16∼20 days of incubation at 20$^{\circ}C$. They were 11.3 to 11.9 $\mu\textrm{m}$ in diameter, having many lumps-like warts on their surface with the length of 1.5 to 1.8 $\mu\textrm{m}$.

• Journal of Microbiology and Biotechnology
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• v.31 no.7
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• pp.999-1010
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• 2021

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the environment. They are highly toxigenic and carcinogenic. Probiotic bacteria isolated from fermented foods were tested to check their ability to degrade and/or detoxify PAHs. Five probiotic bacteria with distinct morphologies were isolated from a mixture of 26 fermented foods co-cultured with benzo(a)pyrene (BaP) containing Bushnell Haas minimal broth. Among them, B. velezensis (PMC10) significantly reduced the abundance of BaP in the broth. PMC10 completely degraded BaP presented at a lower concentration in broth culture. B. velezensis also showed a clear zone of degradation on a BaP-coated Bushnell Haas agar plate. Gene expression profiling showed significant increases of PAH ring-hydroxylating dioxygenases and 4-hydroxybenzoate 3-monooxygenase genes in B. velezensis in response to BaP treatment. In addtion, both live and heat-killed B. velezensis removed BaP and naphthalene (Nap) from phosphate buffer solution. Live B. velezensis did not show any cytotoxicity to macrophage or human dermal fibroblast cells. Live-cell and cell-free supernatant of B. velezensis showed potential anti-inflammatory effects. Cell-free supernatant and extract of B. velezensis also showed free radical scavenging effects. These results highlight the prospective ability of B. velezensis to biodegrade and remove toxic PAHs from the human body and suggest that the biodegradation of BaP might be regulated by ring-hydroxylating dioxygenase-initiated metabolic pathway.

• KSBB Journal
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• v.25 no.5
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• pp.471-477
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• 2010

In order to improve bio-ethanol productivity by various cultivation methods in this paper, the culture modes using food wastes, such as batch culture, high-cell-density fermentation, SSF (simultaneous saccharification and fermentation) by fill & draw, continuous culture by fill & draw were performed and their productivities were compared. SSFs by fill & draw were performed by continuous decompression using 1 L evaporator system, and by 10 L bioreactor without decompression. In addition, the continuous cultures by fill & draw mode using SFW (saccharafied food wastes) medium were performed by changes of 40% culture broth with intervals of 12 h (0.03 $h^{-1}$), 6 h (0.07 $h^{-1}$), 3 h (0.13 $h^{-1}$). Consequently, productivities of bio-ethanol were 2.52 g/L-h and 1.30 g/L-h in batch culture and high- cell-density fermentation, respectively. The productivities of SSF by fill & draw showed 2.24 g/L-h and 2.03 g/L-h in continuous decompression with 1 L evaporator and 10 L bioreactor without decompression, respectively. Also, the productivities in continuous culture by fill & draw modes showed 2.02 g/L-h, 4.07 g/L-h and 6.25 g/L-h by medium change with intervals of 12 h, 6 h, and 3 h, respectively. In conclusion, the highest ethanol productivity was obtained in the continuous culture mode by fill & draw with dilution rate of 0.13 $h^{-1}$.

• Mycobiology
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• v.45 no.1
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• pp.44-47
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• 2017

Ginseng damping-off, caused by the fungal pathogens Rhizoctonia solani and Pythium sp., is a critical disease in ginseng seedling. In a continuing effort to find microorganisms with the potential of acting as a biocontrol agent against Rhizoctonia damping-off, we found that a Streptomyces sp. A501 showed significant antifungal activity against Rhizoctonia solani. In field experiment to test the efficacy of Streptomyces sp. A501 in controlling ginseng damping-off, the incidence of damping-off disease was meaningfully reduced when ginseng seeds were soaked in the culture broth of Streptomyces sp. A501 before sowing. To perform characterization of the antifungal compound, we isolated it from the culture broth of strain A501 through Diaion HP-20 and silica gel column chromatographies and preparative high-performance liquid chromatography. The structure of the antifungal compound was assigned as fungichromin by spectroscopic methods, mainly nuclear magnetic resonance and electrospray ionization-mass analysis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.666-670
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• 1994

To increase the yield of acetic acid production, the author developed the bacterial strain which could brow well in high concentration of ehtanol from the seed culture using in conventional vinegar production factory. By attenuation of the isolated strain in the broth media containing 5-10% ethanol, we could get the strain which could grow in the broth medium containing 10% ethanol. This strain was identified and named as Acetobacter sp. FM-10, and it's cultural characteristics were also investigated. The medium containing 10% ethanol, 5% glucose and 1% yest extract was suitable for the acetic acid production with Acetobacter sp. FM-10. Optimum temperature and pH for the growth of Acetobacter sp. FM-10. were $30^{\circ}C$ and 5.0, respectively. The acidity of culture medium was reached to 9.0 % after 20 days static cultivation at $30^{\circ}C$.

• Food Science and Preservation
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• v.6 no.2
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• pp.239-244
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• 1999

Antimicrobial activity to the extracts of Perilla frutescens Briton var. acuta Kudo was investigated against various foodborne pathogenes or food poisioning microorganisms(Aspergillus flavus KCTC 6143 and KCTC 6961, Aspergillus niger ATCC 4695, Listeria monocytogenes ATCC 15313, Staphylococcus aureus 196E ATCC 13565, Escherichia coli O157:H7 ATCC 43895, Salmonella typhimurium ATCC 13311 and Yersinia enterocolitica). The ethanol extract of Perilla frutescens Briton var. acuta Kudo was very stable over heat at $121^{\circ}C$ for 15 min. In concentration of $1000\mu\textrm{g}$/mL into culture broth(TSB), the ethanol extract of Perilla frutescens Briton var. acuta Kudo showed the strongest antimicrobial activities against Listeria monocytogenes, followed by Staphylococcus aureus 196E, Salmonella typhimurium. Gram negative bacteria(Escherichia coli O157:H7, Salmonella 쇼phimurium, Yersinia enterocolitica) were less sensitive than Cram positive bacteria but the growth of Escherichia coli O157:H7 and Yersinia exterocolitica were inhibited with increasing concentrations of the extract in culture broth.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.316-320
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• 2007

Three phytotoxic compounds were isolated from the culture broth of Chaetomium sp. through silica gel column chromatography and HPLC (RP-18). Their chemical structures were elucidated as chaetoglobosin F, chaetoglobosin C and chaetoglobosin E on the basis of instrumental analyses such as $^1H-NMR,\;^{13}C-NMR$, and HMQC. They inhibited the root growth of barnyard grass with the $IC_{50}$ values of 66, 65, and $67{\mu}g/ml$, respectively.

• KSBB Journal
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• v.14 no.2
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• pp.192-197
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• 1999

marine bacterium Pseudomonas sp. CHCS-2 produced the biosurfactant in the culture broth which contained 2%(w/v) arabian light crude oil and the productivity of biosurfactant was increased with the addition of glucose. The crude oil in the culture broth was degraded by this strain and carbon chain of $_nC_{12}~_nC_{22}$ was completely degradaded during the incubation for 196 h. The crude biosurfactant was purified by Amberlite XAD-7, Sepharose CL-4B and DEAE-Sepharose CL-6B column chromatography. Therefore, 0.21g/L of the purified biosurfactnat was obtained. The purified biosurfactant was a type of lipoprotein and the molecular weight was estimated as 67kDa by SDS-PAGE. The lipid composition was identified as octadecanoic acid by gas chromatography/mass spectrometry. And then, the N-terminal amino acid sequence of the protein was determined as Ser-Val-lle-Asn-Thr-lle-X-Met-lle-Gly-Gln-Gln- and the sequence did not show homology to any other known lipoprotein. Therefore, the purified lopoprotein was predicted novel biosurfactant.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.305-311
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• 2011

The distribution of flocculating activity of culture broth was examined and the major constituent with flocculating activity was identified. Most of flocculating activity was found in culture broth without cells. As the activity was maintained by the digestion with pronase, it suggests that the activity is due to the polysaccharide. The bioflocculant obtained from $Lactobacillus$ $jensenii$ YW-33 was precipitated by 60~80% EtOH fractionation (LJ-80). LJ-80 was separated by ion-exchange chromatography using DEAE-Toyopearl 650C and LJ-80-II showed more potent flocculating activity than those of other fractions. The major activity fraction LJ-80-II was further purified on the gel permeation using Sepharose CL-6B to LJ-80-II-1. GPC (Sepharose CL-6B) and HPLC were used to determine whether LJ-80-II-1 has a homogenecity. The molecular weight of purified LJ-80-II-1 was estimated over 800,000 dalton by gel permeation chromatography. Purified LJ-80-II-1 contained 98.4% total sugar, 0.6% protein. Main sugar of purified LJ-80-II-1 was composed of mannose : galactose : glucose with a molar ratio of 1.61 : 0.25 : 1.00.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1157-1157
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• 2001

Yeast, Kurtzurnanomyces sp. I-11, produces biosurfactant, mannosyl erythritol lipid (MEL), from soya oil. The properties of biosurfactant MEL include low-toxicity and high biodegradability. MEL provides new possibilities for a wide range of industrial applications, especially food, cosmetic, pharmaceutical fields and chemicals for biotechnology. In the fermentation process, techniques of measuring and controlling substrates and products are important to obtain high productivity with optimum concentrations of substrate and product in the culture broth. The measurement system for the concentrations of soya oil and MEL in the fermentation process was developed using near-infrared spectroscopy (NIRS). Soya oil and MEL in the culture broth were extracted with ethyl acetate and NIR spectra was carried out between the second derivative NIR spectral data at 1312 and 2040 nm and MEL concentrations obtained using a thin-layer chromatography with a flame-ionization detector (TLC/FID) method. A calibration equation for soya oil was results of the validation of the calibration equation, good agreement was observed between the results of the TLD/FID method and those of the NIRS method for both constituents. NIR method was applied to the measurement of the concentrations of MEL and soya oil in the practical fermentation and good results were obtained. The study indicates that NIRS is a useful method for measurement of the substrate and product in the glycolipid fermentation.