• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.24 no.2
• /
• pp.117-122
• /
• 1991

Microbial organisms including yeast, Acinetobacter sp. AG-3, Chlorococcum sp., Chlorella sp. and some of their combinations were tested to evaluate growth efficiency of Tigriopus japonicus. Body length and weight of the copepoda were measured during four days experiment. Acinetobacter sp. AG-3, dried yeast(produced Wago), Chlorella sp., Chlorococcum sp. and mixed culture were used as food sources. Yeast(Y.) was the most effective food for the growth during nauplius stage and efficiencies of bacteria(Bact.)+chlorococcum sp.(RA), Chlorococcum sp.(RA), Bact.+chlorella sp.(Ch.), Bact. and Ch. decreased in odor, while for the growth of copepodite and adult, Bact.+RA was the most effective food with decreased efficiency of Y., RA, Bact. + Ch., Bact., Ch. in order. The ratio of weight gain to the food uptaken, after the weight and food units were converted to carbon, was between 21.6 and $68.7\%$, This result suggests that some kinds of bacteria, algae and mixed cultural microorganisms could be good food sources for the growth of copepoda.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.57 no.1
• /
• pp.111-118
• /
• 2015

This research aims to utilize lapilli from the Mt. Baekdusan as environmently-friendly construction material. First of all, the neutralizing method for fabricating lapilli-cement-mixed bioblock was examined. And then, by use of the neuralized bioblock with microorganism for water purification, the growth inhibition effect against the pathogenic coliform bacillus was evaluated. The result regarding growth inhibition effect on pathogenic coliform bacillus indicates that the pretreatment condition, which is a concurrent procession with aqueous solution of 10% di-ammonium Phosphate after water curing, led to pH degraded below 10 which was the target value. Therefore it was concluded that the method was effective on bio-block neutralization. The microorganisms purifying water and di-ammonium phosphate were detected through the examination for microorganism existence on the bioblock, therefore it was concluded that the bioblock composed of lapilli and cement is able to be utilized in various structures as an environment friendly construction material.

• Microbiology and Biotechnology Letters
• /
• v.16 no.5
• /
• pp.352-357
• /
• 1988

Twenty-five out of 35 strains isolated from fermented corn meal produced folic acid. Bacillus licheniformis strain 6 and Enterobacter cloacae strain 18 produced the largest quantities of 1830$\pm$271 ng and 1350$\pm$161 ng per 100$m\ell$ of the assay broth, respectively. B. licheniformis produced maximum yields when initial pH values were 6,7, or 8 and were incubated at 35$^{\circ}C$ for 5 days. The initial pH (range 4-8) had no effect on folic acid production by E. cloacae； 55 $^{\circ}C$ for 5 days was optimal for this bacterium. Added carbohydrates had no effect on the production of total folic acid in the bacterial cells in pure or mixed cultures. However, in their growth media, carbohydrates enhanced the production of free and total folic acid by E. cloacae and in the mixed cultures. Added carbohydrates had no significant (P < 0.05) effect on the production of free and total folic acid by B. licheniformis.

• Journal of Soil and Groundwater Environment
• /
• v.8 no.1
• /
• pp.27-34
• /
• 2003

In this study, potential degradation of MTBE and other gasoline oxygenates by pure culture ENV425 and mixed culture isolated from gasoline contaminated soil using butane as the sources of carbon and energy was examined and compared. Butane monooxygenases(BMO) of butane-grown ENV425 and mixed culture generated 1-butanol as a major metabolite of butane oxidation and addition of acetylene, specific inhibitor of monooxygenase, inhibited both butane oxidation and 1-butanol production. The results described in this study suggest that alkanes including propane, pentane, and butane are effectively utilized as a growth substrate to oxidize MTBE cometabolically. And also BTEX compounds could be the potential substrate of the MTBE cometabolism. Cell density also affected on the MTBE degradation and transformation capacity(Tc). Increasing cell density caused increasing MTBE degradation but decreased transformation capacity. Other result demonstrated that MTBE and other gasoline oxygenates, ETBE and TAME, were degraded by butane-grown microorganism.

• Journal of Korean Society on Water Environment
• /
• v.23 no.2
• /
• pp.281-286
• /
• 2007

A chemical and biological permeable barrier with economic feasibility is suggested to treat landfill leachate in this study. The proposed composite layers consist of bentonite, and polyurethane (PU) foam that is mixed with powdered activated carbon (PAC) and inoculated with microorganisms from local wastewater treatment plant. Each layer is mixed with local sand, and yellow brown soil. Batch tests were conducted to investigate the sorptions of nitrate on the PU foam and PAC, and nitrification/denitrification rate of each layer material. Nitrification occurred in 30 minutes with initial ammonia concentration of 100 mg/L, and the concentration of nitrate attached in the PU foam increased after 270 minutes. Results of denitrification batch tests showed 76.6%, 87.3% and 88% of nitrate removal efficiency at 10%, 20% and 30% of the volume ratio of PU foam, respectively. The pH increased from 7 to 9.42, and alkalinity increased from 980 mg/L to 1720 mg/L during the denitrification batch tests. In the column experiments using the proposed composite layers with 20% of the volume ratio of the PU foam, about 96% of BOD, 63% of COD, 58.1~79.5% of total nitrogen were removed.

• Journal of the Institute of Convergence Signal Processing
• /
• v.19 no.4
• /
• pp.167-173
• /
• 2018

We propose an air purification system that utilizes aerial plant parts and root zone of indoor plants where light is insufficient and air circulation is bad. In order to maximize the air purification effect of the plant, the aerial plant parts illuminates mixed light combining blue and green LED and CRI(Color Rendering Index) LEDs close to natural light, respectively. And the root zone was forcibly circulated by the fan to use the soil as a filter. The indoor air purification system combined with the light source and the fan removed most polluted air in the shortest. In the case of mixed light and CRI LEDs of indoor air purification system, fine dust decreased by 14%, 14.2%, and TVOC(Total volatile organic compounds) decreased by 7.5% and 9.4%, respectively. In the experiment in which the fan was operated for 15 minutes, the TVOC decreased to 97.8%. The photosynthesis of the plant and the use of soil as a filter were able to purify polluted air in a short time. And the fan's temporary operation gave the similar effect of continuous operation.

• Analytical Science and Technology
• /
• v.20 no.1
• /
• pp.1-9
• /
• 2007

The BOD (biochemical oxygen demand) sensor was fabricated by covering a dissolved oxygen (DO) probe with a microbe-impregnated membrane and a dialysis membrane. Various microorganisms isolated from the soils, water and activated sludge have been evaluated for measuring biochemical oxygen demand (BOD); Bacillus species HN24 and HN93 were selected as they exhibited rapid oxygen consumption and fast recovery. Improved BOD sensor could be prepared by using mixed microbes (Bacillus subtilis, Bacillus sp. HN24 and Bacillus sp. NH93) and silicon rubber gas-permeable membrane for DO probe, and by bubbling 50% $O_2$ ($N_2$ valence) through background buffer solution. This system exhibited excellent analytical performance resulting in good linearity ($r^2=0.9986$) from 0 to 100 mg/L level of BOD.

• Journal of Bio-Environment Control
• /
• v.12 no.4
• /
• pp.207-216
• /
• 2003

Most severe problem in production of potted kalanchoe during summer season is retardation of growth caused by high temperature. The aim of this experiment was aimed to investigate the effects of natural products such as algin-oligosacchride and glucosamine oligosaccharide, plant growth promoting rhizovacteria such as Pseudomonas sp. B and Pseudomonas sp. D2, and AG-solution on the growth of potted kalanchoe under the different root zone temperature in the greenhouse. Growth characteristics in terms of plant height, leaf length, leaf width, leaf area, leaf weight, fresh weight of shoot and root and root length were recorded under three root zone temperatures (25$^{\circ}C$, 30$^{\circ}C$, 35$^{\circ}C$). In 25$^{\circ}C$, the mixed treatment of Pseudomonas sp. B and glucosamine oligosaccharide resulted in the best growth in terms of plant height, leaf area and root weight. In 3-$^{\circ}C$, glucosamine oligosaccharide treatment gave fair result in plant height and leaf weight, but the mixed treatemtn of Pseudomonas sp. D2 and algin-oligosaccharide showed better growth on leaf area and root weight. In 35$^{\circ}C$, the mixed treatment of Pseudomonas sp. B and glucosamine oligosaccharide could greatly improve the plant height, leaf area, leaf weight and root weight. These results demonstrated that the mixed treatment of natural products and microorganisms could overcome the detrimental effects caused by high temeprature in the production of kalanchoe.

• Journal of Soil and Groundwater Environment
• /
• v.7 no.4
• /
• pp.87-91
• /
• 2002

Lab scale batch and column tests were performed to investigate the treatability of petroleum contaminated soil using the in-situ soil flushing method. The pyrex column (4.5$\times$25 cm) was used to investigate optimal washing agent, surfactant concentration, mixing ratio, and inlet velocity. The miked surfactant of $POE_{14}$ and SDS were determined as ideal systems for the batch tests. From the results of preliminary tests, mixed surfactant was found to be more harmful for microorganisms. So $POE_{5}$ and $POE_{14}$ were chosen as the surfactant system for the batch study. The washing efficiency for the diesel contaminated soil was increased until 1 %, and decreased after l %. When applied as selected mixed surfactant, the ideal mixed ratio was recognized as 1:1. Therefore we selected miked surfactant $POE_{5}$ and $POE_{14}$, surfactant concentration 1%, and mixed ratio 1:1 for the remediation of diesel contaminated soil. In column tests, the total removal efficiency was improved as the flux of washing agent was increased. At the same pore volume, small flux showed better removal efficiency.

• Journal of Life Science
• /
• v.21 no.11
• /
• pp.1599-1606
• /
• 2011

To evaluate the effects of microorganism agents on oil biodegradation, treatability and microcosm studies were conducted. Petroleum oil degrading bacteria were isolated from enriched cultures of oil-contaminated sediment samples using a mineral salts medium (MSM) containing 0.5% Arabian heavy crude oil as the sole carbon source. After a 5 day-incubation period using MSM, mixed microorganisms of three species (strains BS1, BS2 and BS4) degraded 48.4% of aliphatic hydrocarbons and 30.5% of aromatic hydrocarbons. Treatability and microcosm tests were performed in the three different treatment conditions (AO: Arabian heavy crude oil, AO+IN: Arabian heavy crude oil+inorganic nutrient, AO+IN+MM: Arabian heavy crude oil+inorganic nutrient+mixed microorganism agents). Among these, significantly enhanced biodegradation of aliphatic hydrocarbons were observed in AO+IN and AO+IN+MM conditions, without showing any different biodegradation rates in either condition. However, the degradation rates of aromatic hydrocarbons in an AO+IN+MM condition were increased by 50% in the treatability test and by 13% in the microcosm test compared to those in an AO+IN condition. Taken together, it can be concluded that mixed microorganism agents enhance the biodegradation of aliphatic and aromatic hydrocarbons in laboratory, a treatability test, and a microcosm test. This agent could especially be a useful tool in the application of bioremediation for removal of aromatic hydrocarbons.