• Journal of Plant Biology
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• v.33 no.4
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• pp.309-314
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• 1990

Effect of mannose on auxin-induced ethylene production in corn (Zea mays L.) coleoptiles was studied. Auxin induced ethylene production decreased in proportion to mannose concentrations. The inhibitory effect of mannose appeared after 2 h of incubation. Ethylene production was significantly depressed by mannose at high concentration (10-5M-10-4M) of indole acetic acid (IAA), but not at low concentrations (10-8M-10-6M). The inhibition of auxin-induced ethylene production by mannose was specific, since other sugars such as galactose, glucose, sucrose and mannitol did not have an inhibitory effect. In an effort to elucidate mechanisms of mannose the effect on the auxin induced ethylene production, effect of the sugar on ACC synthase activity and ACC induced ethylene production was studied. Mannose failed to inhibit ACC mediated ethylene production, but decreased both the ACC content and ACC synthase activity in the tissue. These results suggest that the inhibitory effect of mannose on auxin induced ethylene production results from suppression of auxin induction of ACC synthase.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.4
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• pp.300-309
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• 2007

Although parathion is an organophosphate pesticide being legally applied for the purpose of agriculture and is being manufactured, parathion in the air and urinary p-nitrophenol, a metabolite of parathion, were not analysed in Korea. Air of the parathion manufacturing workplace was sampled by OVS-2 tubes using NIOSH 5600 and spot urine of workers was sampled at the end of shift. Parathion and urinary p-nitrophenol were analysed by GC/MS (5973 MSD connected with Agilent 6890 GC) and the protocol was included in this study. It was found that this protocol should be so sensitive that determining parathion in the air and urinary p-nitrophenol below level of ACGIH TLV and BEI be adequate. Another finding was that total sampling volume of air of NIOSH 5600 of 240 L should be adjusted to be less than 120 L due to breakthrough.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.309-310
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• 1998

Visual observation and subjective assessments lack the objective evaluation of laser therapy effects of the epidermal pigmented lesions. In this study, we proposed the two methods; One is CIE(Commission International d'Eclairage) $L^*,\;a^*,\;b^*$ coordinate system($L^*$ : brightness, $a^*$ : red(+) $\sim$green(-) content, $b^*$ : yellow(+) $\sim$blue(-) content), and the other is the relative color difference measurement. And we applied these two methods for quantitative evaluation of the laser therapy effects.

• Journal of Welding and Joining
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• v.14 no.3
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• pp.75-85
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• 1996

In this paper the influence of postweld heat treatment on mechanical properties of SMAW and FCAW stainless steel weldments was examined and the obtained results are as follows ; (1) The amount of $\delta$-ferrite formed by SMAW and FCAW process decreased with increasing holding temperature and time in post weld heat treatment(PWHT), and it was found that the reduced ferrite was transformed into sigma phase after $800^{circ}C{\times}50hr$ PWHT. This sigma phase, even though it was very small, resulted in brittleness of dissimilar weldment between carbon steel and stainless steel in bending test, however in similar weldment between stainless steel and stainless steel was not occured. (2) The chemical composition of sigma phase was measured to 28-30%Cr, 7-9%Mo, 4-6Ni in 316L weldment, and also 35-37%Cr, 0.9-1.0Mo, 6-8%Ni in 309L weldment by EDS analysis.

• Korean Journal of Plant Tissue Culture
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• v.24 no.5
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• pp.295-303
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• 1997

To investigate the response on feeder cell cultures, protoplasts isolated from cell suspensions initiated from mature seed scutellum-derived callus of the Japonica rice variety Taipei 309, were cultured on filter membranes under various conditions. The effects of various factors, such as gelling agents, feeder cell and protoplast densities, species of feeder cells and heat shock treatment, have been investigated to improve protoplast plating efficiencies on filter membranes. Maximum protoplast plating efficiencies were obtained when protoplasts were cultured on KPR medium semi-solidified with Sea Plaque agarose at a density of $5\;\times\;10^{5}\;ml^{-1}$ protoplasts in the presence of Lolium multiflorum as feeder cells (0.5 ml pcv per 10 ml of protoplast culture medium). Pre-culture heat shock treatments for 1 min. and 5 min. to the protoplasts did not give any appreciable increase on the plating efficiency of protoplasts in the presence of feeder cells. Maltose-supplemented medium was superior for plant regeneration from protoplast-derived colonies compared with medium containing only sucrose. The plants were transferred to the glasshouse, flowered and were fertile.

• Journal of Life Science
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• v.33 no.3
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• pp.260-267
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• 2023

Helicobacter pylori infects the mucosa, induces chronic inflammation and ulcers, and is known as a biological carcinogen. Antibiotics are used as therapeutic agents for H. pylori, but there are problems such as resistance. Thus, research is being conducted on the use of lactic acid bacteria (LAB) as an alternative therapeutic agent. There have been many studies on LAB related to kimchi. However, studies related to Gajami Sikhae, a traditional fermented seafood in Korea, are insufficient. In this study, we investigated the inhibitory effect of LAB isolated from Gajami Sikhae on H. pylori and its use as a probiotic. Forty species of LAB isolated from Gajami Sikhae were identified as Lactobacillus plantarum, Lactobacillus brevis, Leuconostoc mesenteroides, and Weisella paramesenteroides, and 10 strains of 40 species were selected through liquid inhibition assay of H. pylori. The selected LAB supernatant at 1%, 5%, and 10% had a growth inhibitory effect on H. pylori 52, 51, e-53, and 309. The adjusted pH of 7.0 was used for the LAB culture supernatant, in reference to a study that the growth of H. pylori is affected by acid. All 10 strains of LAB at 5% and 10% concentration suppressed the growth of H. pylori 52, and 7 strains of LAB at 10% concentration suppressed the growth of H. pylori e-53. LAB also had the effect of suppressing the activity of urease. Finally, LAB isolated from Gajami Sikhae is expected to be useful for eradicating and preventing H. pylori.

• Korean Journal of Environmental Biology
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• v.31 no.1
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• pp.37-44
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• 2013

This study was to investigate water quality and biotic community characteristics in Juam Lake. In water quality, water temperatures was $3.8{\sim}21.2^{\circ}C$, 6.7~8.6 in pH, $64{\sim}76{\mu}s\;cm^{-1}$ in Conductivity, $5.3{\sim}13.2mg\;L^{-1}$ in DO, $2.5{\sim}3.3mg\;L^{-1}$ in COD, $1.0{\sim}5.1mg\;L^{-1}$ in SS, $0.622{\sim}0.841mg\;L^{-1}$ in T-N, $0.007{\sim}0.019mg\;L^{-1}$ in T-P and $2.8{\sim}8.8mg\;m^{-3}$ in Chl-a. Revised Carlson's Index (TSIm) assessment using total phosphorus (TP) and chlorophyll-a domonstrated that the trophic states of Juam Lake were rated as mesotrophic. A total of 53 species of phytoplankton were identified. They were 28 Bacillariophyceae, 13 Chlorophyceae, 3 Cyanophyceae, and 9 Other algal taxa. The standing crops of phytoplankton was ranged from $113cells\;mL^{-1}$ to $2,909cells\;mL^{-1}$. A total of 16 species of zooplankton were identified (10 rotifers, 4 cladocerans and 2 copepods). Total zooplankton abundance was $309ind.\;L^{-1}$ to $435ind.\;L^{-1}$. The collected benthic macroinvertebrates from the surveyed sites in Juam Lake were 1,038 individuals, 33 species, 21 families and 12 orders. A dominant species was Uracanthella rufa and a subdominant species was Ecdyonurus kibunensis. Hydrophytes recorded from Juam Lake were identified 9 taxa. Emerged plants, floating plants among the hydrophytes was classified 8, 1 taxa, respectively. Ecosystem disturbance wildplant by Environment Ministry found were Paspalum distichum var. distichum and Ambrosia artemisiaefolia. A total of 30 species (6 families) were collected fishs from Juam Lake. There were 10 Korean endemic species (33.3% of collected species number) and 3 exotic species (10.0%).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.309-315
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• 1999

Rice seedling test was conducted to check the loging tolerance at ripening stage through evaluating the root characters. Thirteen Korean and foreign rice cultivars with direct seeding adaptable or high quality characteristics were grown in a cell pot and under submerged paddy. The root characters and pushing resistance of rice hill were determined at seedling and ripening stage, respectively. The diameter of crown root at the 7th and 8th leaf stages was thicker in lodging tolerance cultivars than those of others and showed significant-positive correlation with both pushing resistance and crown root diameter of mature plants. Also, the tensile strength of crown root at the 7th and 8th leaf stage showed highly positive correlation with the tensile strength of crown root of mature plants. The number of crown root at 7th leaf stage was significant-positively correlated with that of mature plant. The diameter of seminal root was not significantly correlated with the diameter of crown root throughout the whole growth stage. These results indicate that the diameter, tensile strength and number of crown root associated with root lodging tolerance can be detected with the seedling at about 7th or 8th leaf stage, and the seedling test using the cell pot is an useful and practical method to select lodging tolerant cultivars or lines of rice based on root characters, especially diameter of crown root.

• Korean Journal of Agricultural Science
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• v.44 no.2
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• pp.196-210
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• 2017

The synergistic effect on phosphate solubilization of single- and co-inoculation of two phosphate solubilizing bacteria, Burkholderia cepacia (C1) and Alcaligenes aquatilis (H6), was assessed in liquid medium and maize plants. Co-inoculation of two strains was found to release the highest content of soluble phosphorus (309.66 ?g/mL) into the medium, followed by single inoculation of B. cepacia (305.49 ?g/mL) and A. aquatilis strain (282.38 ?g/mL). Based on a plant growth promotion bioassay, co-inoculated maize seedlings showed significant increases in shoot height (75%), shoot fresh weight (93.10%), shoot dry weight (84.99%), root maximum length (55.95%), root fresh weight (66.66%), root dry weight (275%), and maximum leaf length (81.53%), compared to the uninoculated control. In a field experiment, co-inoculated maize seedlings showed significant increases in cob length (136.92%), number of grain/cob (46.68%), and grain weight (67.46%) over control. In addition, single inoculation of maize seedlings also showed improved result over control. However, there was no significant difference between single inoculation of either bacterial strains and co-inoculation of these two bacterial strains in terms of phosphate solubilization index, phosphorous release, pH of the media, and plant growth parameters. Thus, single inoculation and co-inoculation of these bacteria could be used as biofertilizer for improving maize growth and yield.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.306-309
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• 2005

본 연구는 기능성 발효유로서 티벳산 발효유에서 분리한 효모(Kluyveromyces marxianus)와 유산균(Lactobacillus bulgaricus)의 혼합스타터를 이용한 발효유를 제조하여 배양 기간별 균수측정, pH, 적정산도, Alcohol 함량, 항암활성에 대해 알아보았다. 배양은 산도 0.68%, 최종 pH가 4.5가 되는 시점에서 마치게 되는데 이때의 배양 온도는 $30^{\circ}C$, 배양기간은 36시간이었다. 이때의 균수는 K. marxianus는 $5.3{\times}10^9$) CFU/mL, L. bulgaricus는 $3.2{\times}10^9$ CFU/mL였고 Alcohol 함량은 0.35%까지 증가하였다. 36시간 배양하여 제조된 발효유의 항종양 활성은 Hep-2에 대해서는 90.5%, HEC-1B는 86.6%, SW-156은 60.3%, SK-MES-1은 57.14%의 높은 항종양활성을 나타내었다. 이상의 결과 기존의 유산균 발효유에 효모를 첨가한 알코올 발효유의 제조가 가능하며, 제품의 항종양 활성의 측면에서도 높은 기능성을 나타내는 것으로 나타났다.