• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.223-229
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• 2002

For the research of the natural marine antioxidant, several bacteria were isolated from the coast of jin-Hae in Korea. Among the marine bacteria studied, strain HJ-14, a gram-negative, motile, strait rod, aerobic, and $Na^{+}$ required bacterium showed high activity of 1,1-diphenyl-2-picrylhydrazyl radical scav- enging. The morphological, physiological, and biochemical characteristics of the strain HJ-14 were similar to those of the Alteromonas macleodii ATCC $27126^{T}$ . Thus, it was tentatively identified as Alteromonas sp. HJ-14. The compositions of major fatty acids in cell membrane of Alteromonas sp. HJ-14 were $C_{ 14:0}$ , $ C_{15:0}$ , $C_{16:0}$ and $C_{17:1}$ $_{w8c}$ , which also suggest that it is affiliated with Alteromonas sp. The optimum culture conditions for production of antioxidant materials with Alteromonas sp. HJ-14 were at $25$~$37^{\circ}C$ and pH 6~8. The optimum conditions for the production of antioxidant for carbon, inorganic nitrogen, and sodium chloride sources were 2.5%(w/v) dextrin, 0.5%(w/v) ammonium sulfate, and 2~6%(w/v) sodium chloride, respectively. The hydroxyl radical scavenging ability of Alteromonas sp. HJ-14 broth was 90.03%, which is higher than ascor-bic acid(83.28%) and lower than butylated hydroxyanisole(95.46%) and $\alpha$-tocopherol(97.17%).

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.6
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• pp.818-823
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• 2011

Recently, we showed that green tea extract (GTE) markedly lowers the intestinal absorption of $^{14}C$-benzo[a]pyrene ($^{14}C$-BaP) and enhances its secretion into the biliary route, suggesting a protective role for GTE against body burden. These findings indicate that green tea could be used as an effective dietary means against the toxicity of BaP. The present study, therefore, was designed to investigate if green tea intake could affect the tissue distribution and deposition of $^{14}C$-BaP in rats. Male Sprague-Dawley rats had free access to a nutritionally adequate AIN-93G diet and deionized water. At ~340 g of weight, the rats were injected intraperitoneally with 27.4 kBq of [4-$^{14}C$]-BaP and 5.0 mg of BaP dissolved in $300\;{\mu}L$ of olive oil and then assigned randomly to the following two groups: one group (GTE) of rats was fed the AIN-93G diet with GTE via drinking water at approx. 4.7 mg of catechins/d, whereas the other was fed the same diet but without GTE (control). At 4 wk of dietary treatment with GTE, animals were euthanized and heart, liver, brain, spleen, kidney, retroperitoneal fat, testis, and epididymal fat were collected, weighed, and analyzed for tissue $^{14}C$-BaP. Both the control and GTE groups continuously gained weight throughout the study, but there was no significant difference between the groups. No significant differences were observed in the weights of heart, liver, brain, spleen, kidney, retroperitoneal fat, testis, and epididymal fat. However, the radioactivities of $^{14}C$-BaP, expressed in dpm/g, were significantly lower in the heart, liver, brain, spleen, and epididymal fat of rats receiving GTE as compared to their respective controls. These data indicate that green tea intake markedly lowers tissue accumulation of $^{14}C$-BaP. Taken together, these findings suggest that the decreased tissue levels of BaP by GTE intake may be associated with lowered intestinal absorption of BaP and its enhanced secretion into the bile.

• Journal of the Korean Applied Science and Technology
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• v.14 no.1
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• pp.61-76
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• 1997

Triacylglycerols of the seeds of Ginkgo biloba have been resolved by high-performace liquid chromatography(HPLC} in the silver-ion and reverse-phase modes. The fatty acids were identified by a combination of capillary gas chromatography and gas-chromatography /mass spectrometry as the methyl and /or picolinyl ester. The main components are $C_{18:2{\omega}6}$(39.0mol%), $C_{18:1{\omega}7}$(asclepic acid 21.5mol%), and $C_{18:1{\omega}9}$(oleic acid, 13.8mol%). Considerable amounts of unusual acid such as $C_{20:3{\Delta}^{5,11,14}$ (5.7mol%), $C_{18:2{\Delta}^{5,9}$(2.8mol%), and $C_{18:3}{\Delta}^{5,9,12}$(1.6mol%), were checked. In addition, an anteiso-branched fatty acid, 14-methylhexadecanoic acid, was also present as a minor component(0.9 mol%). The triacylglycerols were separated into 17 fractions by reverse-phase HPLC, and the fractionation was achieved according to the partition numnber(PN) in which a ${\Delta}^5$-non methylene interrupted double bond($^5$-NMDB) showed different behaviour from a methylene interrupted double bond in a molecule with a given cahinlength. Silver-ion HPLC exhibited excellent resolution in which fractions(23 fractions) were resolved on the basis of the number and configuration of double bonds. In this instance, the strength of interaction of a ${\Delta}^5$-NMDB system with silver ions seemed to be weaker than a methylene interrupted double bond system. The principal triacylglycerol species are as follows ; $(C_{18:2{\omega}6)2}/C_{18:1{\omega}7}$, $C_{18:1{\omega}9}/C_{18:1{\omega}7}/C_{18:2{\omega}6}$, $(C_{18:1{\omega}7)2}/C_{18:2{\omega}6}$, $C_{16:1{\omega}7}/C_{18:1{\omega}9}/C_{20:3}{\Delta}^{5,11,14}$, $C_{16:1{\omega}7}/C_{18:1{\omega}7}/C_{20:3}{\Delta}^{5,11,14}$, $C_{18:1{\omega}9}/C_{18:1{\omega}7}/C_{18:2{\omega}6}$, $C_{18:1{\omega}9}/C_{18:2}{\Delta}^{5,5}/C_{20:3}{\Delta}^{5,11,14}$, $(C_{18:1{\omega}7)2}/C_{18:2{\omega}6}$ and $(C_{18:1{\omega}9)2}/C_{18:2{\omega}6}$, while simple triacylglycerols without $C_{18:2{\omega}6})_3$ were not present. Stereospecific analysis showed that fatty acids with ${\Delta}^5$-NMDB system and saturated chains were predominantly located at the site of sn-3 carbon of glycerol backbones. It is evident that there is asymmetry in the distribution of fatty acids in the TG molecules of Ginkgo nut oils.

• Korean Journal of Materials Research
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• v.11 no.5
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• pp.431-437
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• 2001

This research was examined the effect of intercritical heat treatment on the mechanical Properties and retained austenite formation in 0.1C-6.5Mn steels for the development of a high strength high ductility steel. using of transformation induced plasticity due to retained austenite. The stability of retained austenite is very important for the good ductility and it depend on diffusion of carbon and manganese during reverse transformation. It is effective to heat treat at$ 645^{\circ}C$ in order to obtain over 30 vol.% of retained austenite. However, it is more desirable to heat treat at $620^{\circ}C$, considering the volume fraction and mechanical stability of retained austenite. The strength-elongation combination in cold rolled steel sheets after reverse transformed at $620^{\circ}C$ for 1hr was about 4000k9/mm7, but it decreased rapidly with increasing holding time at high temperature due to the decrease of ductility. The addition of 1.1%Si in 0.14C-6.5Mn TRIP steel does not improve the mechanical properties and retained austenite formation.

• Applied Biological Chemistry
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• v.45 no.1
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• pp.30-36
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• 2002

A bioconcentration experiment was performed for killifish using nonradioactive and radioactive butachlor. At 0.036 ppm concentration, the highest bioconcentration ratio $(C_f/C_w)$ and BCF at steady state recorded as 296 and 87 respectively. And at 0.0036 ppm concentration, the highest $C_f/C_w$ ratio was 169 and the BCF was 51 at steady state. Considering the experimental variation of the BCF's, the BCF of butachlor was tentatively determined to be $69{\pm}28$. And the $^{14}C-butachlor$ and its metabolites depurated about 50% within 12 hours and 90% within 30 hours after depuration experiment started. And in vivo metabolites, designated as M-I, M-II, and M-III, were found in killifish and the excretes as butachlor was metabolised.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.261-267
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• 1982

The objective of this study was to test germinability of sesame (Sesamum indicum L.) varieties at low temperatures. Seeds of III sesame varieties representing different maturity groups and countries were tested at four different temperatures between $10^{\circ}C$ and $16^{\circ}C$. Average germination percentages of III varieties were 92%, 57% and 3.3% at $16^{\circ}C, 14{\circ}C$ and $12^{\circ}C$.respectively. The highest daily germination percentage was observed after 4 days of incubation at $16^{\circ}C$, while it was after 8 days at $14^{\circ}C$. A regression analysis indicated that $15^{\circ}C$ as the minimum temperature for satisfactory germination in field conditions. In general, Korean local collections had better germinability than introduced varieties from 6 countries at different latitudes. 'San dong', a Korean local cultivar. showed the highest germination percentage (24%) at $12^{\circ}C$ when the average germination percentage of all varieties was as low as $3.3^{\circ}C$. Early maturity varieties germinated better at $12^{\circ}C$ and $14^{\circ}C$ than medium or late maturity groups, but no difference was observed at $16^{\circ}C$. Although larger seeds showed better germinability within a variety, there seems to be no relationship between seed size and germinability in sesame.in sesame.

• Korean Journal of Environmental Biology
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• v.33 no.2
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• pp.248-255
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• 2015

Induction of regeneration and maturation of the free-living gametophytes of Saccharina japonica was studied at four temperatures (5, 10, 15 and $20^{\circ}C$), four levels of irradiance (5, 10, 20 and $40{\mu}mol\;m^{-2}\;s^{-1}$) and three photoperiods (14 : 10, 12 : 12 and 10 : 14 h L : D). Female gametophyte fragments were maintained in active regeneration without reaching sexual maturity under conditions of $15^{\circ}C$, $20{\mu}mol\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D), whereas the conditions for male gametophytes were slightly different at $15^{\circ}C$, $5{\mu}mol\;m^{-2}\;s^{-1}$, 14 : 10 h (L : D). The sexual maturation of female and male gametophytes took place under $5^{\circ}C$, $20{\sim}40{\mu}mol\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D) and $15^{\circ}C$, $40{\mu}mol\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D), respectively. These results provide basic information for controlling the regenerationand maturation of free-living gametophytes for strain improvement and cross breeding of S. japonica.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.622-630
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• 2017

The induction of regeneration and the maturation of the free-living gametophytes of Undaria pinnatifida were studied at temperatures(5, 10, 15 and $20^{\circ}C$), irradiance (5, 10, 20 and $40{\mu}mol\;photons\;m^{-2}\;s^{-1}$) and photoperiods (14 : 10, 12 : 12 and 10 : 14 h L: D). Female gametophyte fragments were maintained in active regeneration without them reaching sexual maturity under conditions of $15^{\circ}C$, $20{\mu}mol\;photons\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D); by contrast, the conditions for male gametophytes were slightly different at $15^{\circ}C$, $5{\mu}mol\;photons\;m^{-2}\;s^{-1}$, 14 : 10 h (L: D). The sexual maturation of female and male gametophytes took place under $5^{\circ}C$, $20-40{\mu}mol\;photons\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D) and $15^{\circ}C$, $40{\mu}mol\;photons\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D), respectively. These results provide basic information for controlling the regeneration and maturation of free-living gametophytes for srain improvement as well as the cross breeding of U. pinnatifida.

• Journal of Soil and Groundwater Environment
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• v.12 no.6
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• pp.53-59
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• 2007

Optimal quenching curves have been studied for the accurate analysis of $^{14}C$ in groundwater polluted by reducing efficiency of volatile organic compounds (VOCs) in liquid scintillation counter (LSC). The quenching parameters (SQP(E)) were measured for ten VOCs such as benzene, toluene, ethylbenzene, o-(m-,p-)xylene, trichloroethylene (TCE), tetrachloroethylene(PCE), carbon tetrachloride and chloroform. The quenching curves were plotted using $^{14}C$ standard solution and chloroform as a quenching agent. Optimal plotting conditions were determined for standard solution, LSC measuring time and the concentration of chloroform. The quenching effects of chlorinated organic compounds such as TCE, PCE, carbon tetrachloride and chloroform were greater than those of BTEX (benzene, toluene, ethylbenzene and xylene). Optimum measuring time was 100 minutes far 7,000 dpm/mL standard solution. A few mL of chloroform should be added for good quenching curves. These quenching curves have good correlation coefficients (> 0.99) and the curves could be applied to accurate analysis of $^{14}C$ in groundwater and tap water.

• Korean Journal of Weed Science
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• v.10 no.2
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• pp.109-113
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• 1990

In order to determine selective mode of action of naproanilide between rice and paddy weeds, absorption and translocation of $^{14}C$-naproanilide in rice, Echinochloa crus galli, Cyperus serotinus, and Sagittaria pygmaea were studied, Rice plant and Echinochloa crus-galli absorbed less amount of $^{14}C$-naproanilide than Sagittaria pygmaeo and Cyperus serotinus. Less amount of $^{14}C$-naproanilide was translocated into shoots and translocation rate was slower in rice and Ecl:inochloa crzis-galli than that of Sagittaria pygmaea and Cyperars serotinus. Also, 30-40% of $^{14}C$-naproanilide was distributed at tubers of Sagittaria pygmaea and Cyperus serotinus, which explained that higher amount of $^{14}C$-naproanilide was absorbed from tubers. $^{14}C$-naproanilide was gradually decreased in all plant species and finally more radioactivity was determined in Sagittaria pygmaea and Cyperus serotinus than in Echinochloa cars-galli and rice plant after $^{14}C$-naproanilide treated plants were transferred to Kasugai solution.