• Microbiology and Biotechnology Letters
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• v.15 no.6
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• pp.441-445
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• 1987

The gene coding for alkaline amylase of alkalophilic Bacillus sp. AL-8 was cloned and expressed in Escherichia coli which was lack of amylase activity. For the cloning of the alkaline amylase gene, the chromosomal DNA and plasmid vector pBR322 were cleaved at the site of EcoRI and the gene was cloned. The selection of the transformants carrying the amylase gene was based on the their antibiotics resistance and amylase activity of the transformants. The recombinant plasmids pJW8 and pJW200 containing 5.8Kb and 3.0Kb EcoRI inserts respectively were proved to can the alkaline amylase gene. Alkaline amylase expressed in E. coli was characterized. The enzyme was proved to be stable at the range of alkaline pH.

• Food Engineering Progress
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• v.14 no.3
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• pp.263-270
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• 2010

An alkalophilic microorganism named DK-2386, which produces xylanase, was isolated from soil of Taejo-mountain, Cheonan-si, Chungnam, Korea. The isolated strain was characterized as Gram-positive, with size of 0.4${\times}$2.5 ${\mu}$m, spore forming, anaerobic, catalase positive, possessed with hydrolysis abilities of casein, starch, sodium carboxy methyl cellulose, and xylan, reduction of nitrate to nitrite, resistant against lysozyme, urease positive, and motility positive. The color of culture broth was reddish yellow. The strain DK-2386 was identified as Bacillus agaradhaerens by whole cell fatty-acid composition analysis and 16S rDNA sequence analysis. However, it was not identical to Bacillus agaradhaerens 40952 obtained from the Korean Culture Center of Microorganism in its colour of culture broth. Therefore, we have named the newly isolated strain as Bacillus agaradhaerens DK-2386.

• Microbiology and Biotechnology Letters
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• v.11 no.3
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• pp.187-192
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• 1983

Three kinds of xylanases, X-C, X-I, and X-II, were separated from culture filtrate of an alkalophilic bacteria, Bocillus licheniformis OR-1. Their molecular weights were estimated to be 29, 000, 50, 000, and 34, 000, respectively. They were most active at pH 6.0-6.5, and at temperature of 5$0^{\circ}C$. Mercurc ion and p-chloromercurybenzoate inhibited the xylanase activity of X-C and X-II remarkably, whereas X-I was not affected. Xylanase X-I hydrolyzed barley straw xylan liberating xylose, xylobiose, and arabinose, while X-C and X-II produced only xylobiose and xylotriose.

• Microbiology and Biotechnology Letters
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• v.26 no.3
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• pp.195-199
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• 1998

AH alkalophilic Bacillus SP. AIk-7, isolated from soil, produced ethylene. The characteristics of this microorganism is the ability to grow well under the alkaline condition, at pH 10.3. This strain is similar to Bacillus alkalophilus in terms of morphological, physiological and biological characteristics. In observation of relationship of cell growth and ethylene production according to incubation times, the ethylene synthesis mostly occur from the late exponential phase to the death phase of growth. The purpose of this paper is to study the effects of various substrates on the biosynthesis of ethylene in the intact cell and the cell-free system by the Bacillus sp. AIk-7. In both intact cell and cell-free extract, optimum conditions for ethylene production was achieved at pH 10.3 and 3$0^{\circ}C$. Ethylene was effectively produced from L-Met and 1-aminocyclopropane-1-carboxylic acid (ACC). In this case, ACC as the substrate on ethylene production were two fold higher than L-met at each concentration of substrates. On the other hand, the cell-free ethylene-forming system was used as a tool for the elucidation of the biochemical reaction involved in the formation of ethylene by Bacillus sp. AIk-7. Ethylene production in the cell-free system required the presence of manganese and cobalt ion to be stimulated a little. The result obtained in this work suggests that L-met and ACC may be a precursor more directly related to bacterial ethylene production than any other substrates tested.

• Journal of Soil and Groundwater Environment
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• v.21 no.3
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• pp.6-13
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• 2016

The effect of blast oxygen furnace (BOF) slag used as filling materials on the soil environment was studied using column tests that simulated the flow of the BOF slag leachate through the soil layer. The Cu, Mn, Zn, Ni, and F contents of the leachate affected soil were similar to that of the controls (i.e., soils that were not affected by the leachate). The As, Cd, and Pb contents were lower in the leachate affected soils than the controls. The changes in these contaminants contents can be attributed to the interactions between anions such as alkalinity generating anions (e.g., CO₃²⁻, HCO₃⁻, OH⁻) or calcium ions with heavy metals or F, which consequently affected the fate of heavy metals and F in the leachate affected soils. The germination and growth of Spinapis alba in the soils affected by the leachate and the controls were also similar. However, the proportion of alkalophilic bacteria in the soils affected by the leachate significantly increased, and this can be explained by the increased soil pH due to the alkaline leachate. Overall, this study shows that the alkalinity of the BOF slag leachate, rather than the presence of heavy metals and F in the leachate, needs to be considered when the BOF slag is to be reused as structural filling materials.