• KSBB Journal
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• v.14 no.1
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• pp.45-50
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• 1999

This study was focused on investigating the growth properties of a sulfate reducing bacterium Deslfovibrio sp. B5 which has metabolic ability for desulfurization of petroleum. The optimal temperature and pH for growth of Desulfovibiro sp. B5 were $38^{\circ}C$ and 6.6-7.0, respectively. Addition of 10% corn steep liquor to the Postgate medium C resulted in 0.79 g/L cell concentration, corresponding to a 1.8-fold increase in dry cell mass. Acetate concentrations above 10g/$\ell$ inhibited cell growth significantly. $H_2S$ generated from the sulfate reduction also inhibited the growth of Desulfovibrio sp. B5 at a concentration of 10mM total sulfide. But $N_2$ gassing relieved the growth inhibition by $H_2$S and thereby resulted in a 1.75-fold enhancement in specific growth and lactate consumption pattern of Desulfovibrio sp. B5.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.2
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• pp.143-152
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• 1998

The aerosol concentrations of ionic components were measured on a daily basis from a coastal monitoring site located at Kosan, Cheju Island from 26 September to 5 October 1997 as a field-intensive for a LRTAP project The chemical species we investigated include most of important inorganic species (i.e., Cl-, NO3-, F-, SO42-, Na+, NH4+, and K+) and some organic species (i.e. formats, acetate, and methanesulfonate (MSA) ions). The concentration data of those important inorganic and organic species obtained during this study were evaluated to properly address their chemical and physical characteristics. Most of major inorganic components including sulfate, sodium, chloride, and potassium ions exhibited very conservative relationships with each other such that the concentration ratios of any pair are quite analogous to that of seawater ratio. Since the oceans serve as the major sources of ionic constituents, their concentration changes appear to be senstively reflected by the factors affecting air-sea processes such as an increase in wind speed or changes in wind direction. A comparative analysis of sulfur-containing species such as seasalt (SS) and nonseasalt (NSS) sulfate and MSA were also made to assess the factors influencing the S cycling. An evaluation of NSS/SS ratios suggests that most of sulfate be associated with NSS fraction rather than 55 one. The finding of lower MSA/NSS-SO42- ratio along with a line of physical evidence such as intrusion of anthropogenically affected air mass suggests that the oxidation of S species have been promoted under the conditions encountered during the study period. Finally, the concentration data of carboxylic species (such as formats and acetate ions) were also analyzed. Although the existence of temporal trends were difficult to assess, these data indicate that their contribution to the precipitation acidity may not be significant enough.

• Korean journal of applied entomology
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• v.5_6
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• pp.65-69
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• 1968

The effect of respiratory inhibition was investigated by treating conidia or mycelium of Cochliobolus miyabeanus with phenylmercuric 8-oxyquinolinate (PMQ) or. phenylmercuric acetate (PMA) in terms of $O_2$ up take ul/mg dry weight of cells. The results obtained are as follows: 1. In inhibition of mycelial growth, PMQ gave somewhat less effective than PMA, hut there was no remarkable difference between them, and the two indicated strong inhibitory effect on mycelial growth at the range from 0.01 to 1.0 ppm. 2. In inhibition of conidial respiration, PMA gave somewhat stronger than PMQ except at 0.1ppm, but there was no notable difference between them, and it seemed that there was no inhibitory effect at 0.01ppm. 3. PMQ was stronger than PMA in inhibition of mycelial respiration as compared with the cibudail respiration, ration, and the difference between them was about $10\%$. 4. According to the above results, the inhibitory effect of spore germimation by PMQ was the same as to PMA or somewhat lower than that of PMA. The inhibitiry effect of PMQ on mycelial growth was lower than that of PMA.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.433-439
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• 2010

This study was performed to investigate repellent effect of plant essential oils against Bemisia tabaci adult. Among the 20 tested oils, wild mint oil repelled B. tabaci adult significantly (>90%) at a dose of $5{\mu}{\ell}$, but the other oils did not. In dose responses (2, 1, 0.5, $0.1{\mu}{\ell}$) to B. tabaci adult, wild mint oil showed repellent response (77.8~65.7%) significantly with dose-dependent manner. Wild mint oil analyzed by GC/MS revealed that the major components of wild mint oil were menthol (56.5%), menthone (29.0%) and menthyl acetate (14.5%), and the active components responsible for the effective repellency proved to be menthol (77.8%) and menthone (75.8%) when treated the proportion found in original oil. However, menthyl acetate did not show significant repellency. Combined constituents of wild mint oil were showed synergistic effect.