• The Korean Journal of Food And Nutrition
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• v.11 no.6
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• pp.622-628
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• 1998

Microorganisms isolated from soil were tested for their flocculating activity in kaolin suspension, Identification of the best producing CH-23 strain showed that the strain belonged to the Bacillus megaterium. The maximum production of the flocculating from Bacillus megaterium CH-23 was observed in the culture medium containing 2% sucrose, 3% NaNo3, 0.1% K2HPO4, 0.5% NaCl, 0.5% MgSO4.7H2O and 0.01% tryptone at initial pH 7.0 and 25~3$0^{\circ}C$. Flocculating activity was improved to 57% when the culture medium contained Mn2+(0.01% MnSo4). In the culture medium containing Mg2+(0.01% MgSO4.7H2O) and Ca2+(0.01% CaCO3), flocculating activity were reached to 48% and 33%, respectively.

• Korean Journal of Environmental Biology
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• v.19 no.1
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• pp.87-92
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• 2001

For the biological treatment of industrial wastewater containing high concentration of phenol, isolation and characterization of phenol - degrading bacterium were carried out. A bacterial strain P2 capable of degrading phenol was isolated from contaminated soils by enrichment culture technique and identified as the genus Rhodococcus by morphological, cultural, biochemical characteristics, and Biolog system. The optimal medium composition and cultural conditions for the growth and degradation of phenol by Rhodococcus sp. P2 were 0.1% of (NH$_4$)$_2$SO$_4$, 0.2% of KH$_2$PO$_4$, 0.25% of Na$_2$HPO$_4$ㆍ12$H_2O$, 0.2% of MgSO$_4$ㆍ7$H_2O$, and 0.008% of CaC1$_2$ㆍ2$H_2O$ along with initial pH 8.5 at 3$0^{\circ}C$. Rhodococcus sp. P2 could grow with phenol as the sole carbon source up to 1,800 ppm in batch cultures, but did not grow in medium containing above 2,000 ppm of phenol. When 800 ppm phenol was given in the optimal media, Rhodococcus sp. P2 completely degraded it within 24 h. Meanwhile, 1,800 ppm of phenol was degraded within 9 days. Rhodococcus sp. P2 could utilize toluene, n-hexane, xylene and benzene as sole carbon source .

• KSBB Journal
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• v.9 no.2
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• pp.91-97
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• 1994

In this study, Pullulan Production from whey medium by Aureohsidium pullulans was investigated. When the Pullulan production from whey medium was carried outs final cell concentration was similar to sucrose basal medium but Pullulan concentration was less than 5g/$\ell$. For pullulan production from whey medium, adaptation culture technique was tried on lactose and galactose base medium When the adaptation culture technique was not applied, the maximum concentration of pullulan was 3.4g/$\ell$ for lactose, 2.5g/$\ell$ for galactose. Adapted strains produced 10~12g/$\ell$ from lactose, 10~11g/$\ell$ from galactose. The pullulan production from lactose basal medium was 13.5g/$\ell$ for lactose adapted strains and 18.6g/$\ell$ for galactose adapted strains. When the adapted strains were inoculated on whey medium, maximum pullulan production was obtained at initial pH 3.0.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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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.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.235-238
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• 2000

The production of polysaccharide from Paecilomyces japonica was studied in the shake flask culture. For the cell growth and the polysaccharide production, the optimum synthetic medium was glucose peptone(YMP) medium. The flask culture conditions for the polysaccharide production were $27^{\circ}C$ and 200rpm with the initial pH 9 for 8days cultivation.

• KSBB Journal
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• v.7 no.2
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• pp.149-153
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• 1992

Pseudomanas fluorescens was selected from mushroom and studied in both batch and continuous culture in order to find out optimum conditions for cultivation. P. fluorescens is an aerobic bacterium and antagonistic to Pseudomonas tolaasii which causes blotch disease on the mushroom cap. Cells of P. fluorescens were grown well on medium containing 30g/L of glucose, whereas the growth was inhibited with the glucose concentration at higher than 30g/L. The highest value of specific growth rate and productivity were obtained when using 10g/L of yeast extract. Optimum concentrations of $NH_4Cl$ and $(NH_4)_2SO_4$ for culture were found to be 1.0g/L and 0.1g/L respectively. Optimum concentration of $MgSO_4{\cdot}7H_2O$ used as a sulfur source was 1.0g/L. It was also found that the cell concentrations were at the maximum level when grown on the medium containing 1.0g/L of $KH_2PO_4$ and 0.1g/L of $CaCl_2$. Also, the optimum culture conditions were $30^{\circ}C$ and pH 6.0. Cultivation of P.fluorescens at high initial dissolved oxygen (D.O) value led to a decrease of bacterial productivity in batch culture. Maximum productivity was achieved at 68 for the initial D.O value.

• KSBB Journal
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• v.17 no.6
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• pp.509-514
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• 2002

Experiments were carried out to optimize the fermentation conditions for the production of erythritol by salt-tolerant mutant, Candida magnoliae M26. The optimum conditions of erythritol production showed a 1.0 vvm aeration and 500 rpm agitation at 28$\^{C}$ with an initial medium pH of 7.0. The pH control during the fermentation did not improve the erythritol yield and productivity. The maximum erythritol concentration of 143.3 g/L was obtained with 57% yield and 0.70 g/L-h productivity from 250 g/L of glucose and 5 g/L of yeast extract under an optimum fermentation conditions. The medium containing 0.5 M KCl or 0.5 M NaCl enhanced the production of erythritol and glycerol. However, glycerol production increased and erythrtiol production decreased by increasing the concentration of NaCl or KCl.

• KSBB Journal
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• v.14 no.1
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• pp.31-35
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• 1999

A biosorption of azo and reactive dyes into the intact and modified biomass of Penicillium janthinellum were investigated. Initial pH of medium affected the initial adsorption rate and decolorization. The initial optimum pH was found to be 2.0, and the maximum adsorption rates of dyes were $40^{\circ}C$. The reactive dyes called Apollocion Red 7EB, Apollofix Red SF-3B and Apollocion Red H-E3B showed the high initial adsorption rates as 0.06, 0.086 and 0.079 mg/g.min, respectively. A mixture of dyes containing azo and reactive dyes was adsorbed to the biomass of Pen. janthinellum and revealed that the initial adsorption rate was 0.084 mg/g.min. Both percent decolorization and the influence on the dye adsorption rate. Modified biomass of Pen. janthinellum was also investigated for the dye adsorption and the superior dye loading performance was observed compared with the ion-exchange/chelating resins used for removal of Apollocion Red 7EB.

• Applied Biological Chemistry
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• v.35 no.6
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• pp.443-448
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• 1992

To investigate the production of monoterpenoids by Mentha pipperita cells in suspension culture, effects of media formulation, plant growth hormones, initial pH of the media, and cold stress on the production of essential oil and menthol were analyzed. Among the media employed, Lin-Staba medium resulted in the best essential oil production. Addition of 100 mg/l of yeast extract to the Lin-Staba medium induced the cells to produce large amount of essential oil and high content of menthol (0.39 g/l and 19.6%, respectively). In the effect of plant growth hormone, auxine were more effective than cytokinins. At initial pH of 4.7, oil production was good but menthol content was low. However at pH 5.7 the trend was reversed. When the culture temperature was lowered from $27^{\circ}$ to $10^{\circ}$ during 6 hour-dark period, growth was not changed much but essential oil production and menthol content was increased and reached to 528 mg/l and 21%, respectively.

• Journal of Korean Dental Science
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• v.4 no.2
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• pp.52-58
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• 2011

Purpose: Modifications of implant design have been related to improving initial stability. The purpose of this study was to investigate their respective effect on initial stability between two tapered implant systems (self-tapping vs. non-self-tapping) in medium density bone using three different analytic methods. Materials and Methods: Self-tapping implant (GS III$^{(R)}$; Osstem Implant Co., Busan, Korea) and non-self-tapping implant (Replace Select$^{(R)}$; Nobel Biocare, G$\H{o}$teborg, Sweden) were investigated. In Solid rigid polyurethane blocks of artificially simulated Quality 2 bone, each of the 5 implants was inserted according to the manufacturer's instructions for medium-bone drilling protocol. Evaluation of initial stability was carried out by recording the maximum insertion torque (IT) and performing the resonance frequency analysis (RFA), and the pull-out test. Results: The IT and RFA values of self-tapping implant were significantly higher than those of non self-tapping implant (P=.009 and P=.047, respectively). In the pull-out values, no significant differences were found in implants between two groups (P=.117). Within each implant system, no statistically significant correlation was found among three different outcome variables. Conclusions: These findings suggest that design characteristics of implant geometry significantly influence the initial stability in medium bone density.