• Journal of Applied Biological Chemistry
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• v.43 no.4
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• pp.250-253
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• 2000

The effects of high relative humidity (RH) on the physicochemical properties and microbial activity of mature green tomatoes ('Dombito') during refrigerated storage were determined at three temperatures (5, 10, and $15^{\circ}C$) and four different RH levels (91, 94, 97, and 99%). At each temperature, the weight loss rates of tomatoes at different levels of RH were significantly (p<0.05) different from each other. For the samples stored at $10^{\circ}C$, the weight losses were generally higher than those for the samples at $15^{\circ}C$ within the same RH level (i.e., greater vapor pressure deficit). The color change rates ('a' value) showed positive slopes, indicating that the tomato color was changing from green to red. Neither bacteria nor fungi caused visible damages to the samples, and the microbial counts were below 650 colony forming units/$cm^2$ during the test period.

• Journal of Applied Biological Chemistry
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• v.43 no.3
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• pp.161-164
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• 2000

The effects of storage temperature and high relative humidity (RH) on the weight loss, color change, and microbial activity of a mushroom ('Sylvan' hybrid white) were investigated. The experiment was performed at three temperature (5, 10 and $15^{\circ}C$) and four different relative humidity levels (91, 94, 97 and 99%). The weight loss of the tested samples had a highly correlated linear relationship with storage time at each RH level during storage. Both the storage temperature and RH levels in the experiment had signigicant effects (p<0.05) on the weight-loss rate of the tested samples. The loss whiteness of mushrooms was not significantly affected (p>0.05) by RH ranges at the same temperature. No visible damage was caused by either bacteria or fungi in all samples during storage.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.1
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• pp.134-140
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• 1997

Objectives of this study were to determine effects of insulin on acetyl-CoA carboxylase (ACC) activity and correlate this activity with relative amounts of ACC in MAC-T cells. MAC-T cells were grown in Medium 199 supplemented with fetal bovine serum (5%), cortisol ($1{\mu}g/ml$), and insulin ($1{\mu}g/ml$). At confuluence, the cells were transferred to $100mm^2$ culture dishes coated with the extracelluar matrix. After 10 h of incubation, the media were replaced with media without fetal bovine serum and the concentration of insulin was lowered to 5 ng/ml. After 24 h, the media were changed to contain the varying concentrations of insulin and incubations continued for 48 h. The addition of insulin resulted in increases in the specific activity of ACC. The maximal effects of insulin on the ACC activity occurred at concentrations of insulin, 1,000 ng/ml. In contrast, the relative change in lactate dehydrogenase (LDH) activity in response to increasing insulin concentration was minimal as compared to the effects of insulin on ACC. Transblot and enhanced chemiluminescence (ECL) analysis indicated that the increase in ACC activity in MAC-T cells caused by insulin were due to actual increases in amounts of enzyme.

• Mycobiology
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• v.46 no.3
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• pp.287-295
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• 2018

In this study, we evaluated the effect of different temperatures (10, 20, 30, and $40^{\circ}C$) and relative humidities (RHs; 12, 44, 76, and 98%) on populations of predominant grain fungi (Aspergillus candidus, Aspergillus flavus, Aspergillus fumigatus, Penicillium fellutanum, and Penicillium islandicum) and the biocontrol activity of Pseudomonas protegens AS15 against aflatoxigenic A. flavus KCCM 60330 in stored rice. Populations of all the tested fungi in inoculated rice grains were significantly enhanced by both increased temperature and RH. Multiple linear regression analysis revealed that one unit increase of temperature resulted in greater effects than that of RH on fungal populations. When rice grains were treated with P. protegens AS15 prior to inoculation with A. flavus KCCM 60330, fungal populations and aflatoxin production in the inoculated grains were significantly reduced compared with the grains untreated with strain AS15 regardless of temperature and RH (except 12% RH for fungal population). In addition, bacterial populations in grains were significantly enhanced with increasing temperature and RH, regardless of bacterial treatment. Higher bacterial populations were detected in biocontrol strain-treated grains than in untreated control grains. To our knowledge, this is the first report showing consistent biocontrol activity of P. protegens against A. flavus population and aflatoxin production in stored rice grains under various environmental conditions of temperature and RH.

• Journal of Environmental Science International
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• v.31 no.4
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• pp.311-318
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• 2022

In this study, we analyzed the relationships between weather factors and photosystem II activity (F_v/F_m), as a measure of photochemical efficiency, in three cool-season turfgrasses commonly planted on golf courses in Jeju, South Korea: perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.), and creeping bentgrass (Agrostis palustris Huds.). In all three turfgrasses, F_v/F_m was higher during late summer than during early summer. However, in late summer, F_v/F_m was significantly lower in perennial ryegrass than in the other two species. In early summer, F_v/F_m in perennial ryegrass and Kentucky bluegrass was positively correlated with mean low temperature and extreme minimum temperature, whereas, in late summer, this parameter in Kentucky bluegrass and creeping bentgrass was positively correlated with relative humidity, and in creeping bentgrass was negatively correlated with mean high temperature, mean low temperature, and extreme maximum temperature. These results indicate that raising low temperatures is favorable for perennial ryegrass and Kentucky bluegrass in early summer, whereas, in late summer, the lowering of high temperatures proves to be beneficial for creeping bentgrass, and raising relative humidity is conducive to the growth of Kentucky bluegrass and creeping bentgrass. These findings will contribute to improving the selection and management of turfgrasses on golf courses and sports fields.

• Journal of Korean Society of Rural Planning
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• v.24 no.2
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• pp.91-100
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• 2018

This study aims to identify more reasonable and efficient development plans to engage local university students in landscape improvement projects in rural areas. To survey university students, residents, administrators and experts involved in such projects on important considerations in this regard, SWOT analysis was employed to identify important factors, followed by analytic hierarchy process (AHP) to evaluate their relative importance, identify problems and suggest implications for improvement. The results are summarized as follows: the relative importance of the SWOT group was in the order of opportunity, strength, threat, and weakness. For each SWOT factor, the relative importance of strengths was in the order of students' aspiration and passion, availability of creative ideas and designs, and improved attachment to their community. The relative importance of weaknesses was in the order of the lack of spontaneous participation of residents, short preparation periods and insufficient budgets, and the lack of experience in similar projects. The relative importance of opportunities was in the order of young students' activity itself being a boost factor to the community, students' endeavors arising a consensus among residents, and students feeling a sense of duty as representatives of their school. The relative importance of threats was in the order of projects being one-shot, temporary events, immaturity, and differences in preferences between older and younger generations. To draw an overall ranking of the sub-factors evaluated, the overall relative importance of the decision-making factors was evaluated. Among the sub-factors for each SWOT group, young students' activity itself being a boost factor to the community as an opportunity factor was shown to be the most important, while the lack of experience in similar projects was shown to be the least important as administrators and experts made appropriate interventions in each stage.

• Korean Journal of Microbiology
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• v.19 no.3
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• pp.137-141
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• 1981

Occurrence and distribution of sucrose metabolizing enzymes in oral streptococci had been studied. In these studies, the carbohydrate component of the culture medium had been glucose. I have extended these studies by analyzing bacterial culture supernatants for the relative content of hexosyltransferases, namely glucosyl and fructosyltransferase. As a carbohydrate, fructose was used. The growth measured for nine oral streptococci (Strptococcus mutans strains BHT, ING, AHT, 6715, LM-7, and SL-1 ; Streptococcus sanguis 903, 9811, and M-5) varied. The level of glucosyltansferase activity also varied among S. mutans strains, and its level in S. sanguis was relatively low. Fructosyltansferase activity of the various strains fluctuated more than of glucosyltransferase. S.mutans strain LM-7 had significantly higher level of both enzymes. As a whole, fructose-grown cultures had generally an agreeable trend of enzyme activity to those from glucose-grown cultures.

• Journal of Ginseng Research
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• v.5 no.2
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• pp.108-113
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• 1981

Major quality indices for deterioration of red ginseng including oxidation of lipids and change of brown color intensity were periodically investicated during storage of Red Ginseng under various water activity conditions at 3$0^{\circ}C$. The results obtained were summarized as follows. 1. The monolayer moisture contents were 3.25% and 6.3% for red ginseng and red ginseng powder, respectively, and the corresponding water activities were 0.14 and 0.16, respectively. 2. Oxidation of lipids as measured by TBA value increased with an increase in relative humidity and storage period 3. Under storage conditions above 42% R H., brown color intensity also increased in similar fashion to that of oxidation of lipids as relative humidity and storage Period increased 4. It was concluded from above results that water activity of Red Ginseng should be kept less than 0.57 so that red ginseng could Preserve stable qualify.

• Journal of Life Science
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• v.12 no.5
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• pp.544-548
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• 2002

The object of this study was to investigate nitrogen fixation activity of rhizobium inoculated at seed coat when drought condition was applied in flowering period of soybean c.v. Samnamkong. The rhizobia used in this experiment were indigenous rhizobium, R2l4, RJl-29, USDA110 and USDA122. The experiment was done with 1/2000 Wagner pots in laboratory and greenhouse and was tested in completely randomized design with four replications. Nitrogen fixation activity in coventional culture was the highest in R2l4 and indigenous rhizobium among the five rhizobia strains. As given drought condition from flowering to maturity, nitrogen fixation activity was higher in R2l4 and RJl-29 than indigenous rhizobium. Leaf area and relative index (drought/convention) of pod weight were higher in USDA122, RJl-29 and R2l4 than indigenous rhizobium as given drought condition from flowering to maturity. High positive correlation was observed between nitrogen fixation activity of rhizobium and relative index(drought/convention) of pod weight. High negative correlation was observed between respiration of plant and relative index (drought/convention) of leaf area.

• YAKHAK HOEJI
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• v.43 no.2
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• pp.278-284
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• 1999

This study deals with the biological changes in mice after ${\gamma}-irradiated$. Four weeks old BALA/c mice were irradiated with 6.5Gy of ${\gamma}-ray$ on the fifth day after oral administration of radioprotectants such as ascorbic acid, tocopherol and cysteine. Control group was irradiated with 6.5Gy without pre-administration of radioprotectors. Blood cells and sperm cells were counted and body, testis and spleen were weighed 3 days after irradiation. And also liver antioxidant activity and range of spleen immune cells were measured. Differences in most biological parameters were not clearly distinguished between experimental groups. However, the relative spleen weight, the relative testis weight and the population size of spleen immune cells such as T helper cells, B cells and macrophages measured by means of FACS showed significant difference between irradiated and radioprotectant administered group. It is concluded that the relative spleen weight, the relative testis weight and the population size of spleen immune cells are easy and useful parameters for assessing the effect of radioprotective substances and for quantifying biological damage of radiation, as well.