• Journal of Microbiology and Biotechnology
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• v.22 no.6
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• pp.800-805
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• 2012

Licochalcone E was firstly isolated from licorice root in 2005, which belongs to the retrochalcone family. Studies on the biological activities of licochalcone E were in the initial stage. In the study, we demonstrated that licochalcone E has potent antimicrobial property against Staphylococcus aureus. Furthermore, via hemolysis, Western blot, and real-time RT-PCR assays, we have shown that subinhibitory concentrations of licochalcone E dose-dependently reduces the production of ${\alpha}$-toxin in both methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA). The data suggest that licochalcone E may deserve further investigation as a potential therapeutic against S. aureus infections, or the structure of licochalcone E may be used as a basis for chemical synthesis of novel anti-S. aureus compounds.

• Atmosphere
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• v.19 no.2
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• pp.183-198
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• 2009

The purpose of this study is to summarize the tropical cyclone (TC) activity of 2008 over the western North Pacific including the verification of the official track and intensity forecast errors of these TCs. The TC activity - frequency, Normalized Typhoon Activity (NTA), and life span - was lower than 58-year (1951-2008) average. 22 tropical cyclones of tropical storm (TS) intensity or higher formed in the western North Pacific and the South China Sea in 2008. The total number is less than 58-year average frequency of 26.4. Out of 22 tropical cyclones, 11 TCs reached typhoon (TY) intensity, while the rest 11 TCs only reached severe tropical storm (STS) and tropical storm (TS) intensity - six STS and five TS storms. One typhoon KALMAEGI (0807) among them affected the Korea peninsula. However, no significant impact - casualty or property damage - was reported. On average of 22 TCs in 2008, the Korea Meteorological Administration (KMA) official track forecast error for 48 hours was 229 km. There was a big challenge for individual cyclones such as 0806 FENGSHEN and 0817 HIGOS presenting significant forecast error, with both intricate tracks and irregular moving speed. The tropical cyclone season in 2008 began in April with the formation of NEOGURI (0801). In May, four TCs formed in the western North Pacific in response to enhanced convective activity. On the other hand, the TC activity was very weak from June to August. It is found that the unusual anti-cyclonic circulation in the lower level and weak convection near the Philippines are dominant during summertime. The convection and atmospheric circulation in the western North Pacific contributed unfavorable condition for TC activity in the 2008 summertime. The 2008 TC activity has continued the below normal state since mid 1990s which is apparent the decadal variability in TC activity.

• Journal of Life Science
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• v.25 no.12
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• pp.1458-1469
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• 2015

Many organic solvent-tolerant bacteria have been isolated from all environments such as soil, waste-water, even deep sea after first isolation report of organic solvent-tolerant bacterium. Most organic solvent- tolerant isolates have been determined to be Gram-negative bacteria, because Gram-negative bacteria have inherent tolerance property toward hostile organic solvents more than Gram-positive bacteria. The mechanisms of organic solvent tolerance have been elucidated extensively using mainly organic solvent-tolerant Gram-negative bacteria. The solvent-tolerance mechanisms in Gram-positive bacteria can be found in comparatively recent research. Organic solvents exhibited different toxicity depending on the solvent, and the tolerance levels of organic solvent-tolerant bacteria toward organic solvents were also highly changeable among species and strains. Therefore, organic solvent-tolerant bacteria could coped with solvent toxicity and adapted to solvent stress through the multifactorial and multigenic adaptative strategies. They could be survived even in the hyper concentrations of organic solvents by mechanisms which include: changes in cell morphology and cell behaviour, cell surface modifications, cell membrane adaptations, solvent excretion pumps, chaperones and anti-oxidative response. The aim of this work is to review the representative solvent tolerant bacteria and the adaptative and tolerance strategies toward organic solvents in organic solvent-tolerant bacteria, and their potential industrial and environmental impact.