• Korean Journal of Clinical Laboratory Science
• /
• v.48 no.3
• /
• pp.230-236
• /
• 2016

Economic growth has increased the living standards around the world. Water pollution, in particular, is a public relations issue because it poses a direct threat to everyone's lives. As of recently, the production of taste and odor (T&O) compounds has been a common problem in the water industry. The adsorption process using granular activated carbon (GAC) has been the most widely used process. The objectives of this study were to evaluate the microorganisms before and after the backwashing of GAC and to identify the species of the microorganisms found. Five dominants microorganisms were confirmed after the microfiltration process from backwashing of GAC, and the dominant bacterial species were found to be ${\beta}$-proteobacterium species, Porphyrobacter donghaensis, Polaromonas rhizophaerae, Hydrogenophaga species, and Pseudonocardia species. However, when UV treatment after microfiltration was performed, Hydrogenophaga species and Psedonocardia species were eliminated. Herein, I conclude that the UV treatment post microfiltration process is more efficient than microfiltration process alone. The findings of this study may provide useful information regarding the management of microfiltration process.

• Korean Journal of Environmental Agriculture
• /
• v.24 no.4
• /
• pp.379-385
• /
• 2005

This study was conducted to find out a useful bioremediation technology for heavy metal contaminated soil and water. We isolated strain CPB from heavy metal contaminated soil and evaluated the tolerance level and adsorption capacity of strain CPB to heavy metals (Strain is not determined yet). Strain CPB showed variable tolerance limit to different kinds heavy metal or concentrations of heavy metals. The growth of strain CPB was significantly inhibited by mixed heavy metals (Cd+Cu+Pb+Zn) than that of by single heavy metal. Strain CPB showed high binding capacity with Pb (Pb>Cd>Cu>Zn). In general, strain CPB showed high uptake of heavy metals such as Pb, Cd and Cu. It was observed that the capacity of heavy metal uptake from mixture of heavy metals was reduced in comparison with single heavy metal treatment. But total contents of heavy metal bound with cell in mixed heavy metal showed higher than in single heavy metal treatment. Heavy metal adsorption in cells was affected by several external factors, such as temperature and pH etc.. The optimum temperature and pH of the adsorption of heavy metal into cells were ca. $25{\sim}35^{\circ}C$ and pH ca. $5{\sim}7$, respectively. A large number of the electron dense particles were found mainly on the cell wall and cell membrane fractions, which was determined by transmission electron microscope. Energy dispersive X-ray spectroscopy revealed that the electron dense particles were the heavy metal complexes the substances binding with heavy metals.

• Korean Journal of Soil Science and Fertilizer
• /
• v.47 no.6
• /
• pp.510-517
• /
• 2014

The purpose of this study was to analyze microbial hazards for cultivation environments and personal hygiene of strawberry and tomato farms at the growth and harvesting stage. Samples were collected from thirty strawberry farms and forty tomato farms located in Korea and tested for Staphylococcus aureus and Bacillus cereus. To investigate the change in the distribution of the S. aureus and B. cereus, a total of 4,284 samples including air born, soil or medium, mulching film, harvest basket, groves and irrigation water etc. were collected from eight strawberry farms and nine tomato farms for one year. As a result, total S. aureus and B. cereus in all samples were detected. Among the total bacteria of strawberry farms, S. aureus (glove: $0{\sim}2.1Log\;CFU/100cm^2$, harvest basket: $0{\sim}3.0Log\;CFU/100cm^2$, soil or culture media: 0~4.1 Log CFU/g, mulching film: $0{\sim}3.8Log\;CFU/100cm^2$), B. cereus (glove: $0{\sim}2.8Log\;CFU/100cm^2$, harvest basket: $0{\sim}4.8Log\;CFU/100cm^2$, soil or culture media: 0~5.3 Log CFU/g, mulching film: $0{\sim}4.5Log\;CFU/100cm^2$) were detected in all samples. The total bacteria of tomato farms, S. aureus (glove: $0{\sim}4.0Log\;CFU/100cm^2$, harvest basket: $0{\sim}5.0Log\;CFU/100cm^2$, soil or culture media: 0~6.1 Log CFU/g, mulching film: $0{\sim}4.0Log\;CFU/100cm^2$), B. cereus (glove: $0{\sim}4.0Log\;CFU/100cm^2$, harvest basket: $0{\sim}4.3Log\;CFU/100cm^2$, soil or culture media: 0~5.9 Log CFU/g, mulching film: $0{\sim}4.7Log\;CFU/100cm^2$) were detected in all samples. The contamination of S. aureus and B. cereus were detected in soil, mulching film and harvest basket from planting until harvest to processing, with the highest count recorded from the soil. But S. aureus and B. cereus were not detected in irrigation water samples. The incidence of S. aureus and B. cereus in hydroponics culture farm were less than those in soil culture. The amount of S. aureus and B. cereus detected in strawberry and tomato farms were less than the minimum amount required to produce a toxin that induces food poisoning. In this way, the degree of contamination of food poisoning bacteria was lower in the production environment of the Korea strawberry and tomato, but problems can be caused by post-harvest management method. These results will be used as fundamental data to create a manual for sanitary agricultural environment management, and post-harvest management should be performed to reduce the contamination of hazardous microorganisms.

• Journal of Korean Foot and Ankle Society
• /
• v.13 no.2
• /
• pp.150-155
• /
• 2009

Purpose: To help the empirical antibiotics selection in diabetic foot infection patients, we investigated prevalence of microorganisms and their antibiotics sensitivity results. Materials and Methods: Patients who came to our clinics to treat diabetic foot infections with deep ulceration and were followed up more than 6 months until complete recovery were adopted. From March 2006 to June 2009, there were 140 patients who corresponded with such a inclusion criteria. Wound cultures were done by deep tissue or bone debris at first visit to our clinics. Microorganisms which was documented by wound culture and most susceptible antibiotics by minimum inhibitory concentrations were surveyed retrospectively. Results: Microorganisms were confirmed in 113 cases (80.7%). In the other 27 cases (19.3%), there were no cultured microorganisms. In bacterial growth group, there were 72 cases (63.7%) of gram-positive bacteria and 41 cases (36.3%) of gram-negative bacteria. All of them were aerobic microorganisms and there were no anaerobic microorganisms. Methicillin-sensitive staphylococcus aureus was the most common pathogen and accounted for 35 cases (31.0%). As other common pathogens, there were Enterobacter cloacae (11 cases, 9.7%), pseudomonas aeruginosa (10 cases, 8.8%), Methicillin-resistant staphylococcus aureus (10 cases, 8.8%) and enterococcus faecalis (6 cases, 5.3%), and so on. Common susceptible antibiotics in gram positive microorganism were vancomycin (60 cases, 83.3%), teicoplanin (60 cases, 83.3%), nitrofurantoin (60 cases, 83.3%) and ciprofloxacin (53 cases, 73.6%). In gram negative ones, common susceptible antibiotics were imipenem (35 cases, 85.3%), piperacillin/tazobactam (33 cases, 80.5%) and gentamicin (31 cases, 75.6%). Conclusion: Methicillin-sensitive Staphylococcus aureus in gram positive and enterobacter cloacae in gram negative was the most common pathogen in each group. Ciprofloxacin and gentamicin might be adaptable as a first-line empirical antibiotics in infected diabetic foot patients.

• Journal of Nutrition and Health
• /
• v.18 no.3
• /
• pp.234-241
• /
• 1985

The purpose of this study was to investigate changes in nutritive quality of fermented wheat bran prepared by culturing with a microorganism, Aspergillus oryzae, in an attempt to improve the quality of protein in feedstuff. After incubation of wheat bran with Aspergillus oryzae, the contents of chemical composition, including amino acids, riboflavin and amino-nitrogen were increased, but the level of nitrogen free extract was reduced. The effects of supplementation of fermented wheat bran on the rat diets were evaluated by measuring growth rate, feed efficiency and biological values, such as NPU, PER and NPR. Sixty four male Sprague Dawley rats of 5-6 weeks of age were adopted for the feeding trial for 10 days period, and levels of dietary protein were set at 10%. The %contribution of protein from casein, wheat bran and fermented wheat bran for the other dietary treatments were, in the order, 50-50-0%, 50-30-20%, 50-20-30% and 50-0-50%, respectively. In the result of this study, no significant difference were observed in the amount of feed intake body weight gain and feed efficiency. On the whole, the values of NPU, PER and NPR of all the fermented wheat bran groups appeared to be higher than those of the group whose half of the protein was from wheat bran.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.21 no.3
• /
• pp.115-120
• /
• 2015

In this experiment, sliced yams (5 mm size) were used for research. Alcohol treatment and blanching treatment were used in this experiments. Color change, hardness, microorganism total count, and PPO activity of the packaged yam were measured. In result, colors of the treated yam were significantly changed in alcohol treatment with different concentration. 5% alcohol treatment is better than 10% alcohol treatment in browning inhibition of fresh-cut yam. But in blanching treatment, color change had no significant different. PPO activity of 1 min blanching packaged yam were decreased 50% and PPO activity of 5 min blanching packaged yam were decreased 85%. In the case of hardness were decreased in both experimental groups. especially 1 min, 3 min and 5 min blanching films, hardness were decreased more than 10 N. Also, both treatments are inhibited the growth of microorganisms effectively.

• Microbiology and Biotechnology Letters
• /
• v.44 no.3
• /
• pp.333-340
• /
• 2016

An alkaline protease was purified and characterized from an alkalophilic microorganism, Bacillus sp. DK1122, isolated from soil in central Korea. The optimum temperature and pH for the growth of the producer strain were 40℃ and pH 9.0, respectively. The protease was produced aerobically at 40℃ after 24 h incubation in modified Horikoshi I medium (pH 9.0) containing 0.5% (w/v) glucose, 0.8% (w/v) yeast extract, 0.5% (w/v) polypeptone, 0.1% (w/v) K₂HPO₄, 0.02% (w/v) MgSO₄·7H₂O, 1% (w/v) Na₂CO₃, and 3% (w/v) NaCl. The alkaline protease was purified by 70% ammonium sulfate precipitation of the culture supernatant of Bacillus sp. DK1122, followed by CM-Sepharose chromatography. The molecular weight of the enzyme was estimated to be 27 kDa on the basis of SDS-PAGE. The optimum temperature and pH for the protease activity were 60℃ and pH 9.0, respectively. Addition of CaCl₂ increased the thermal stability of the purified protease, where 90% of protease activity was retained at 60℃ for up to 3 h. Consequently, it is expected that the alkaline protease from this study, exhibiting stability at pH 7–9 and 60℃, may be promising for application in the food and detergent industries.

• Microbiology and Biotechnology Letters
• /
• v.39 no.4
• /
• pp.330-336
• /
• 2011

Bacterial strains exhibiting fibrinolytic activity were screened from traditional Korean soybean sauce. The Fibrinolytic activities of the various isolated microorganism were further examined and the superior strain YJ11-21 was selected for further analyses. Gene sequence analysis of 16S rDNA of the YJ11-21 strain revealed Bacillus licheniformis. Optimal culture conditions were investigated in order to maximize the production of the fibrinolytic enzyme by YJ11-21. Amongst the carbon sources tested, glucose was the most effective for enzyme production and amongst the nitrogen sources tested, yeast extract was seen to be the most effective. A one percent addition of NaCl to the medium resulted in the highest fibrinolytic activity. Interestingly, a 10% addition of NaCl resulted in a high activity together with a high cell growth rate. Therefore, YJ11-21 is speculated of being a halotolerant. The optimum pH and temperature for enzyme production were a pH of 9.0 and $30^{\circ}C$, respectively.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.8
• /
• pp.1219-1225
• /
• 2010

Actinobacillus succinogenes, a representative succinicacid-producing microorganism, is seriously inhibited by ammonium ions, thereby hampering the industrial use of A. succinogenes with ammonium-ion-based materials as the pH controller. Therefore, this study isolated an ammonium-ion-tolerant mutant of A. succinogenes using a continuous-culture technique in which all the environmental factors, besides the stress (ammonium ions), were kept constant. Instead of operating the mutant-generating system as a nutrient-limited chemostat, it was used as a nutrient-unlimited system, allowing the cells to be continuously cultured at the maximum specific growth rate. The mutants were isolated on agar plates containing the acid-base indicator bromothymol blue and a high level of ammonium ions that would normally kill the parent strain by 100%. When cultured in anaerobic bottles with an ammonium ion concentration of 354 mmol/l, the mutant YZ0819 produced 40.21 g/l of succinic acid with a yield of 80.4%, whereas the parent strain NJ113 was unable to grow. When using $NH_4OH$ to buffer the culture pH in a 3.0 l stirredbioreactor, YZ0819 produced 35.15 g/l of succinic acid with a yield of 70.3%, which was 155% higher than that produced by NJ113. In addition, the morphology of YZ0819 changed in the fermentation broth, as the cells were aggregated from the beginning to the end of the fermentation. Therefore, these results indicate that YZ0819 can efficiently produce succinic acid when using $NH_4OH$ as the pH controller, and the formation of aggregates can be useful for transferring the cells from a cultivation medium for various industrial applications.

• Journal of Conservation Science
• /
• v.32 no.3
• /
• pp.353-364
• /
• 2016

The materials of sculptured stone property around the Hyeonleung Royal Tomb in Guri consist mainly of high weathered of granitic rocks with magnetite-series. Deterioration characteristics occurred highly with microorganism, soil inflow and black contaminants at the burial mound zone. As a result of deterioration evaluation, stone surface around the burial mound zone show serious comprehensive damage of soil inflow (50.5%) and lichen coverage (47.6%) which are the major damaging factors, and there are about 8.6% of biological growth noticeably in the north side. Surface contaminants and the discoloration had the complex causes. Gypsum occurred between joints of stones and the major contaminant type, darkening which was analyzed organic bodies caused discoloration. From result of ultrasonic velocity measurements, there are mean value of 2,195 m/s with highly weathered (HW) grade. Most of the stone properties showed 4 to 5 weathered grade. Therefore, it turned out that sculpture stone properties require conservation treatments. To remove soil accelerating damage factors and lichen occupying high percents, the cleaning process is necessary and consolidation, rejoining and filling are needed as well. Also, consideration on removing conservation materials containing Ca and e fflorescence is required and retreatments need to be considered.