• Applied Biological Chemistry
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• v.27
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• pp.68-79
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• 1984

An increased population and rapidly expanding industrial development have led to enormous amounts of various domestic and industrial wastes. The proper disposal of ever-increasing wastes is a growing global problem. Land treatment is one of the rational approaches that are environmentally safe and economically practical. It has long been practised in many sites. Recycling of industrial wastes on agricultural land can provide better possible means for maintaining environmental quality and utilizing waste-resources. Even though industrial wastes are beneficial as soil amendment and fertilizer, they have some limitation on land application because of wide variability as well as physicochemical problem in their composition. A direct application of solid and liquid wastes on land is being practised in Korea and some experimental results are presented. The direct application of fermentation waste on rice resulted in a 6 percent yield increase. Another organic residue from glutamic acid fermentation is widely used not only as a direct application as a liquid fertilizer but also for a raw material of organic compound fertilizer. These wastes are much promising as sources of plant nutrients, since they have large amounts of nutrients, especially nitrogen with few toxic metals. On the other hand, fertilizers developed from inorganic industrial wastes include calcium silicate, calcium sulfate and ammonium sulfate. The calcium silicate fertilizer simply produced from slag, by-product of iron and steel manufacturing plant is one of the most successful example of the conversion of wastes to fertilizer and slag production capacity totals to over three million MT/year. About 200,000 MT of calcium silicate fertilizer is currently applied in the paddy rice every year. Calcium sulfate, a waste from the wet phosphoric acid process is to some extent used as a filler of compound fertilizers but quite large quantites are directly applied for the reclamation of tidal flat.

• KSBB Journal
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• v.14 no.1
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• pp.51-57
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• 1999

The immobilization of nitrifier consortium was carried out for the application to recirculating aquaculture system(RAS). The abilities of $NH_4^+$-N removal by immobilized nitrifier consortia prepared with boric acid treated, ethanol treated, ad freezing-thawing treated PVA beads at the concentration 15% were examined. To identify the possibility of applying the beads in the fluidized bed reactor, characteristics of beads were evaluated. The suitable bead was boric acid treated beads which had highest ammonia removal rate of 16.09 g/$m^3$/day. It took 12 days for nitrifier consortium immobilized beads to be stable for the removal of $NH_4^+$-N. Life spans of the beads were more than three months with aggressive aeration in the fluidized ed reactor when nitrifier consortia immobilized in PVA beads were used. In order to apply the nitrifier consortium immobilized beads to aquaculture facility, the continuous reactor was used for 49 days with synthetic aquacultural water containing 2 mg/L ammonia. The highest ammonia removal rate of 31.87 g/$m^3$/day was observed when hydraulic residence time was 0.6 hour(36min.).

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.4
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• pp.381-388
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• 1984

Addition of heavy textured red earth is being recommended to improve the texture and nutirent retention capacity of sandy soil in Korea. However, farmers are not favorable to this description because of high transportation cost and hard working. To solve this pending problem a field experiment was carried out to investigate the possibility of application of Zeolite as a foreign earth material to improve the physical and chemical characteristics of sandy soil. The experiment results suggested that Zeolite mixed with the basal N fertilizer would be substituted for other foreign earth materials in aspects of rice yield and nitrogen uptake of rice shoot. On the other hand, ammonium adsorption characteristics of soil and amendments were studied.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.602-609
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• 2012

Burkholderia anthina R-4183, Burkholderia diffusa R-15930 and Burkholderia stabilis LMG 14294 isolated from green house soils (Gongju-Gun area, South Korea) were characterized and their phosphate solubilizing ability was assessed. Under in vitro culture conditions, all three species were proved to be effective in solubilizing phosphates in varying degrees. Strain Burkholderia anthina exhibited the highest phosphate solubilization in NBRIP medium ($665{\mu}g\;ml^{-1}$) followed by Burkholderia diffusa ($630{\mu}g\;ml^{-1}$) and Burkholderia stabilis ($578{\mu}g\;ml^{-1}$). However, solubilization of $FePO_4$ and $AlPO_4$ was found to be poor in all the strains. Acidification by means of gluconic and oxalic acids accumulation in the culture medium could be the possible mechanism responsible for phosphate solubilization. Glucose at the rate of 3% was found be the best carbon source for Burkholderia anthina while other two Burkholderia species showed maximum phosphate solubilization at 2% of glucose. In the case of nitrogen sources, ammonium and nitrate were equally effective in solubilizing phosphates by Burkholderia species. Despite a slight decrease in phosphate solubilization observed at increasing temperature, all three Burkholderia species could withstand a temperature of $30-35^{\circ}C$, pH at the range of 7-9 and the presence of NaCl (up to 2.5%) without much compromising the phosphate solubilization. As shown with potted mung bean seedlings, all the three isolates could enhance soil fertility and plant growth indicating their great potential to be used as bio-inoculants.

• Journal of Sensor Science and Technology
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• v.27 no.5
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• pp.345-351
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• 2018

We employed an unprecedented technique to synthesize porous $WO_3@SnO_2$ nanofibers exhibiting core-shell and fiber-in-tube configurations. Firstly, 2-methylimidazole was uniformly incorporated in as-spun nanofibers containing ammonium metatungstate hydrate and the sacrificial polymer (polyacrylonitrile). Secondly, the 2-methylimidazole on the surfaces of nanofibers was complexed with tin(II) chloride ($SnCl_2$) via simple impregnation of the as-spun nanofibers in ethanol containing tin(II) chloride dihydrate ($SnCl_2{\cdot}2H_2O$). The presence of vacant p-orbitals in tin (Sn) and the nucleophilic nitrogen on the imidazole ring allowed for the reaction between $SnCl_2$ and 2-methylimidazole, forming adducts on the surfaces of the as-spun nanofibers. The calcination of these nanofibers resulted in porous $WO_3@SnO_2$ nanofibers with a higher surface area ($55.3m^2{\cdot}g^{-1}$) and a better response to 1-5 ppm of acetone than pristine $SnO_2$ NFs synthesized using a similar method. An improved response to acetone was achieved upon functionalization of the $WO_3@SnO_2$ nanofibers with catalytic palladium nanoparticles. This work demonstrates the potential application of $WO_3@SnO_2$ nanofibers as sensing layers for chemiresistive sensory devices for the detection of acetone in exhaled breath.

• Microbiology and Biotechnology Letters
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• v.8 no.1
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• pp.9-18
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• 1980

During an extensive screening tests of yeasts for their RNA formation, it was found that Cryptococcus laurentii had especially high RNA content and high dry cell weight, when hydrolyzate of sliced and dried sweet potatoes was used as a carbon source. Growth conditions of this strain were examined, and the most desirable results were obtained at 48 hours of cultivation on a reciprocal shaker at 3$0^{\circ}C$ with initial pH 6.0. Under the above conditions, the RNA content and yield of dry cells were investigated using various media compositions. Ammonium sulfate 0.40%, peptone 0.6 ％, and yeast extract 0.4% were appeared to be favorable as a nitrogen sources. The optimum concentrations of K $H_2$P $O_4$, M $n^{++}$, C $O^{++}$ were 0.05 ％, 0.1 ％, and 0.001 ％, respectively. Ca-pantothenate, 400$\mu\textrm{g}$/$m\ell$, showed relatively favorable effects as a growth factor. The maximum RNA content obtained in this study was 16.8 ％ of the total dry cell weight.t.t.

• Journal of Microbiology and Biotechnology
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• v.19 no.5
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• pp.462-467
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• 2009

Cyclosporin A (CyA) produced by Tolypocladium inflatum is a promising drug owing to its immunosuppressive and antifungal activities. From an industrial point of view, the necessity to obtain a suitable and economic medium for higher production of CyA was the aim of this work. The present study evaluated the effect of different fermentation parameters in solid state fermentation, such as selection of solid substrate, hydrolysis of substrates, initial moisture content, supplementation of salts, additional carbon, and nitrogen sources, as well as the inoculum age and size, on production of CyA by Tolypocladium inflatum MTCC 557. The fermentation was carried out at $25{\pm}2^{\circ}C$ for 9 days. A combination of hydrolyzed wheat bran flour and coconut oil cake (1:1) at 70% initial moisture content supported a maximum production of $3,872{\pm}156\;mg$ CyA/kg substrate as compared with $792{\pm}33\;mg/kg$ substrate before optimization. Furthermore, supplementation of salts, glycerol (1% w/w), and ammonium sulfate (1% w/w) increased the production of CyA to $5,454{\pm}75\;mg/kg$ substrate. Inoculation of 5 g of solid substrate with 6 ml of 72-h-old seed culture resulted in a maximum production of $6,480{\pm}95\;mg$ CyA/kg substrate.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.4
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• pp.414-420
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• 2006

Effluent from an anaerobic digestion system with an elutriated phased treatment(ADEPT, Anaeorbic Digestion Elutriated Phase Treatment) for piggery waste treatment using anaerobic ammonium oxidation(ANAMMOX) process was used as a substrate of partial nitrification reactor. In mesophilic condition($35^{\circ}C$), controlling parameters of nitrite accumulation were HRT, pH, free ammonia(FA) and hydroxylamine rather than dissolved oxygen. Bicarbonate alkalinity consumption ratio including bicarbonate stripping and buffering was 8.78 g $Alk._{comsumed}/g\;NH_4-N_{converted}$. In steady state for 1 day of HRT and $2.7{\sim}4.4mg/L$ of DO, $NO_2-N/NH_4-N$ ratio of partial nitrification effluent was about $1{\sim}3$, which was applicable to ANAMMOX reactor influent for the combined partial nitrification-ANAMMOX process.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.181-187
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• 1999

For the selection of an effective antagonistic biocontrol agent, we have isolated an antagonistic bacterium which produced extracellular chitinase, from a local soil of Kyongju, Korea. The selected strain was identified as Serratia proteamaculans 3095. The chitinase produced from Serratia sp. 3095 showed antifungal activity which can attack the hypha surface of Fusarium oxysporum and F. solani. The carbon and nitrogen sources for chitinase production were 0.15% colloidal chitin and 0.1% ammonium sulfate, respectively. Glucose in the chitinase production medium might inhibit the production of chitinase by feed back repression. The antagonistic Serratia sp. 3095 also showed a powerful biocontrol activity against F. oxysporum through in vitro test and in vivo pot test.

• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.383-388
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• 2003

A bacterium producing the extracellular xylanase and CMCase was isolated from soil and has been identified as Bacillus sp. The isolate, named Bacillus sp. A-7, was shown to be very similar to Bacillus licheniformis on the basis of its biochemical and physiological properties. The maximum xylanase and CMCase production were obtained when 2.0% (w/v) glucose and 0.3% (w/v) yeast extract were used as carbon source and nitrogen source, respectively. The best mineral conditions for xylanase and CMCase production were 0.1%(w/v) $CaC1_2$. Among the various feedstuffs, 1.0%(w/v) soybean meal was selected for the best xylanase and CMCase production.