• Journal of Microbiology and Biotechnology
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• 제17권7호
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• pp.1147-1151
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• 2007

Biodegradation of endocrine-disrupting bisphenol A was investigated with several white rot fungi (Irpex lacteus, Trametes versicolor, Ganoderma lucidum, Polyporellus brumalis, Pleurotus eryngii, Schizophyllum commune) isolated in Korea and two transformants of T. versicolor (strains MrP 1 and MrP 13). I. lacteus degraded 99.4% of 50 mg/l bisphenol A in 3 h incubation and 100% in 12 h incubation. which was the highest degradation rate among the fungal strains tested. T. versicolor degraded 98.2% of 50 mg/l bisphenol A in 12 h incubation. Unexpectedly, the transformant of the Mn-repressed peroxidase gene of T. versicolor, strain MrP 1, degraded 76.5% of 50 mg/l bisphenol A in 12 h incubation, which was a lower degradation rate than wild-type T. versicolor. The removal of bisphenol A by I. lacteus occurred mainly by biodegradation rather than adsorption. Optimum carbon sources for biodegradation of bisphenol A by I. lacteus were glucose and starch, and optimum nitrogen sources were yeast extract and tryptone in a minimal salts medium; however, bisphenol A degradation was higher in nutrient-rich YMG medium than that in a minimal salts medium. The initial degradation of endocrine disruptors was accompanied by the activities of manganese peroxidase and laccase in the culture of I. lacteus.

• Journal of Plant Biology
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• 제34권4호
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• pp.289-296
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• 1991

Cultures of hairy root induced from ginseng(Panax C.A. Meyer) transformed with Agrobacterium rhizogenes (strain A4, ATCC 15834) were established and morphologically two different hairy root strains (HB1, HB2) were obtained. To determine the optimum growth rate, the hairy root (HB2) was cultured in various liquid medium supplemented with or without plant growth hormone. The growth rate of hairy root cultured on MS medium was 1.3-3.1 times higher than those cultured on other media, and the optimum sucrose concentration and pH were 3-6%, 5.5-6.5, respectively. Also, the growth rate of hairy root was increased when 0.02 M ammonium nitrate, 1.2 mM potassium phosphate (monobasic) and 0.5 mg/l IBA were supplied to liquid medium. The saponin patterns and contents of hairy root (HB2) were determined by TLC and HPLC. The crude saponin contents were 4.67% and the total saponin contents were 1.0%, on dry weight basis.

• KSBB Journal
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• 제11권5호
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• pp.600-605
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• 1996

Taxus brevifolia와 Taxus cuspidata 현탁세포배 양에서 taxa!의 생산에 가장 적합한 초기 접종농도 를 결정하기 위해 접종농도를 세포생체중량으로 2.5, 5 5, 7.5, 10 g/flask가 되도록 변화시켜 세포의 생장 과 taxol의 생산을 측정하였다. Taxus brevifolia의 경우 초기 접종농도가 높을수록 lag phase가 감소되 는 경향을 보였으며, 두 가지 세포주(Taxus bre­1 vifolia와 Taxus cuspidata)에서 모두 초기 접종농도 를 5 g/flask가 taxol의 생산에 최척 임을 확인할 수 있었다. Taxol 생산에 가장 척합한 초기 접종농도로 생장배지와 생산배지에 세포를 접종시켰을 때 생장 배지에서는 taxal이 검출되지 않았지만 6% 자당을 이용한 생산배지에서는 9일째 taxol이 최대로 생산 되었다가 이후 다시 줄어드는 경향을 보였다.

• 한국축산식품학회지
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• 제31권2호
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• pp.176-182
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• 2011

The bacteriocin-producing lactic acid bacteria Enterococcus faecium DB1 was isolated from Korean traditional gajami sikhae. Culture conditions were optimized by response surface methodology (RSM) to maximize bacteriocin DB1 production. E. faecium DB1 displayed the highest bacteriocin activity when grown in modified MRS medium containing sucrose, rather than glucose, as a carbon source. The effects of temperature, initial pH, and sucrose concentration were tested to determine the optimum conditions for maximum bacteriocin production by E. faecium DB1. A central composite design was used to control the three variables in the experiment. RSM revealed that the optimum values for bacteriocin production were 27.66 g/L sucrose, temperature of $34.37^{\circ}C$, and an initial pH of 6.54. A 2.08-fold increase in bacteriocin production was obtained with sucrose-containing MRS medium compared to production in standard MRS medium.

• Mycobiology
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• 제39권2호
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• pp.85-91
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• 2011

We investigated the effect of nutritional and environmental factors on Ophiocordyceps longissima mycelial growth. The longest colony diameter was observed on Schizophyllum (mushroom) genetics complete medium plus yeast extract, Schizophyllum (mushroom) genetics minimal medium, and Sabouraud dextrose agar (SDA); however, malt-extract yeast-extract agar, SDA plus yeast extract, yeast-extract malt-extract peptone dextrose agar, SDA, oatmeal agar, and potato dextrose agar showed higher mycelia density. A temperature of $25^{\circ}C$ was optimum and 7.0 was the optimum pH for mycelial growth. Colony diameter was similar under light and dark conditions. Maltose and yeast extract showed the highest mycelial growth among carbon and nitrogen sources respectively. The effect of mineral salts was less obvious; however, $K_3PO_4$ showed slightly better growth than that of the other mineral salts tested. Among all nutrition sources tested, complex organic nitrogen sources such as yeast extract, peptone, and tryptone were best for mycelial growth of O. longissima. Ophiocordyceps longissima composite medium, formulated by adding maltose (2% w/v), yeast extract (1% w/v), and $K_3PO_4$ (0.05% w/v) resulted in slightly longer colony diameter. In vitro mycelial O. longissima growth was sustainable and the production of fruiting bodies could be used for commercial purposes in the future.

• Journal of Microbiology and Biotechnology
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• 제12권2호
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• pp.279-285
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• 2002

Phytase (myo-inositol hexakisphosphate phospho-hydrolase, EC 3.1.3.8) catalyzes the hydrolysis of phytate (myo-inositol hexakisphosphate) to release inorganic phosphate. A bacterial strain producing phytase was isolated from soil around a cattle shed. To identify the strain, cellular fatty acids profiles, the GC contents, a quinine-type analysis, and physiological test using an API 20NE kit were carried out. The strain was identified to be a genus of Pseudomonas sp. and named as Pseudomonas sp. YH40. The optimum culture condition for the maximum productivity of phytase by Pseudomonas sp. YH40 were attained in a culture medium composed of $1.0\%$ (w/v) glycerol, $2.0\%$ (w/v) peptone, and $0.2\%$ (w/v) $FeSO_4{\cdot}7H_2O$. Within the optimal medium condition, the production of phytase became highest after 10 h of incubation, and the maximal phytase production by Pseudomonas sp. YH40 was observed at $37^{\circ}C$ and pH 6.0.

• 한국미생물·생명공학회지
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• 제24권5호
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• pp.560-566
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• 1996

A strain capable of producing thermostable chitinase suitable for chitooligosaccharide production was isolated from high temperature environment and identified as Bacillus licheniformis. The chitinase from Bacillus licheniformis KFB-Cl4 was only induced by addition of colloidal thitin into the basal medium as carbon source, showing the decrease of the chitinase production by supplernental addition of other carbon sources into the medium containing 1.0% colloidal chitin. Among organic and inorganic nitrogen sources, yeast extract was the most effective for the increase of total activity and specific activity, and had high affinity for the enzyme production. The optimum temperature of cell growth and thermostable chitinase production was 55$\circ$C. The optimum culture medium was composed of 1.2% colloidal chitin, 0.15% K$_{2}$HPO$_{4}$, 0.05% KH$_{2}$PO$_{4}$, 0.01% MgSO$_{4}$-7H$_{2}$O, 0.1% yeast extract (pH 6.5). Bacillus licheniformis KFB-C14 produced the thermostable chitinase of 3.89 units per ml culture fluid and 7.4 units per mg protein under rotary shaking at 150 rpm for 40 hr.

• 자연과학논문집
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• 제12권1호
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• pp.69-79
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• 2002

PDA-calcium phosphate 평판배지를 이용하여 인산가용화활성을 가진 850종의 세균을 분리한 후 인광석에 대한 인산가용활성이 가장 강한 HS-2 균주를 선발하였다. 선정 균주의 형태학적, 배양학적 및 생리생화학적 특성 등을 조사한 결과 Azotobacter sp. HS-2로 동정되었고, 이 균주을 인광석을 0.1%함유한 Potato dextrose Broth배지 (pH 6.0)에 접종하여 $30^{\circ}C$에서 5일 배양했을 때 인광석이 가장 많이 분해되었고 0.5M의 수산을 첨가했을 때 분해율이 약 50% 증가되었다.

• Journal of Dairy Science and Biotechnology
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• 제39권3호
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• pp.87-93
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• 2021

This study analyzed and compared growth characteristics under large-scale fermentation at 35℃ of three microorganisms with the ability to reduce odor-producing substances in livestock. The three microorganisms (Bacillus subtilis FWC1, Bacillus amyloliquefaciens NAAS1, and Pichia farinosa NAAS2) evaluated in this study have been proven effective in reducing odor-inducing substances. Bacillus subtilis FWC1 exhibited the highest viable cell count when using 2% maltodextrin as carbon source, 0.05% soy-peptone as nitrogen source, and 0.3% yeast extract. The optimum media composition for B. amyloliquefaciens NAAS1 was 1.2% modified-starch with 0.8% yeast extract. The spore formation rate in the mass production of the Bacillus strains was over 90%, indicating that optimal growth medium compositions have been identified. In the case of P. farinosa NAAS2, our optimized growth medium [2% (w/v) glucose and 1% (w/v) yeast extract] improved biomass production.

• 한국미생물·생명공학회지
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• 제24권1호
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• pp.92-100
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• 1996

For the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)(P(3HB-co-3HV)) from butyric acid and valeric acid, 10 strains of bacteria capable of producing P(3HB-co-3HV) were isolated from soil. Among them, the strain HJ-067 showed the best ability of producing P(3HB-co-3HV), and was indentified as a Azotobacter sp. For the production of P(3HB-co-3HV), the optimum concentrations of butyric and valeric acid were 3.0g/l, respectively. The most effective nitrogen source was $(NH_4)_{2}SO_4$ at an optimum concentration of 0.75g/l, which was equivalent to 21.36 in C/N ratio. Deficiency of the cationic metal ions ($Zn^{2+},\;Co^{2+},\;Mn^{2+}$) in the proguction medium had stimulating effect on P(3HB-co-3HV) accumulation, especially in the manganese. deficient medium. The optimum temperature for P(3HB-co-3HV) production was 27$^{\circ}C$ and the optimum initial pH was 7.0. Under the optimum conditions, 1.82g/l of P(3HB-co-3HV) and 3.00g/l of dry biomass were produced after 36 hour cultivation, and the P(3HB-co-3HV) yield and HV% were 60.60% (w/w), 15.92%, respectively.