• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.427-431
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• 2013

Paprika fruits should be stored and distributed at above $7^{\circ}C$ to prevent chilling injury but the small amount of paprika that transports with other horticultural products in refrigerated container by ship usually stored less than $5^{\circ}C$ for other products. In this case, paprika fruits cannot help exposing chilling temperature, so that the paprika must be lost marketable value during a long period of transfer. This study was conducted to compare the alleviated effects of high $CO_2$ treatment (passive MAP), heat (hot water dipping), and UVc treatment on chilling injury of paprika fruits due to low temperature storage, and also to decide if these treatments can be used for transporting under $5^{\circ}C$. After each treatment the paprika were put in the low temperature storage ($4^{\circ}C$) for 20 days and afterwards change the in room temperature ($20^{\circ}C$) for 5 days. The fresh weight loss of all the treatments except the high $CO_2$ treatment showed around 7~12% after 25 days of storage and the ethylene concentration showed periodical increases and decreases as around 3 ${\mu}l/l$. The $CO_2$ concentration was rapidly increased 33% carbon dioxide in high $CO_2$ treatment during room temperature storage after cold storage for 20 days. The firmness which is key quality characteristics during storage and is decreasing caused by chilling injury was not significantly different among all treatments. However, the firmness of stored paprika was maintained highest in the treated with hot water dipping. Therefore, HWD and UVc treatment that showed 60% of electrolyte leakage in the $4^{\circ}C$ control (chilling injury control) and similar level with the $7^{\circ}C$ control (non-chilling injury control) would be effective to alleviate chilling injury in the stored paprika.

• Journal of Bio-Environment Control
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• v.18 no.2
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• pp.148-152
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• 2009

Numerous studies have presented evidence that global atmospheric carbon dioxide ($CO_{2}$ ) concentration and temperature is increasing every year. Both of the $CO_{2}$ and temperature are important components for photosynthesis activity of plants and thusgrowth and yield. However, little information is available in terms of the reaction of vegetable plants to increased $CO_{2}$ concentration and temperature, and also the reaction to a complex condition of both increased $CO_{2}$ concentration and temperature. The aim of this research was therefore to investigate changes in growth, photosynthetic activity and ultra-cellular structure of leaf tissue of Chinese cabbage. Plants were grown under either of elevated $CO_{2}$ concentration (elevated $CO_{2}$, 2-fold higher than atmospheric $CO_{2}$ ) or elevated temperature (elevated temp, 4$^{\circ}C$ higher than atmospheric temperature), under both of elevated $CO_{2}$ concentration and elevated temperature (elevated temp+$CO_{2}$), and under atmospheric $CO_{2}$ concentration and temperature (control). The treatment of 'elevated temp' negatively affected leaf area, fresh weight, chlorophyll and starch content. However, when the treatment of 'elevated temp' was applied coincidently with the treatment of 'elevated $CO_{2}$', growth and photosynthetic performance of plants were as good as those in the treatment of 'elevated $CO_{2}$', Microscopic study resulted that the highest starch content and density of cells were observed in the leaf tissue grown at the treatment of 'elevated $CO_{2}$', whereas the lowest ones were observed in the leaf tissue grown at the treatment of 'elevated temp'. These results suggest that when Chinese cabbage grows under a high-temperature condition, supplement of $CO_{2}$ would improve the growth and yield. In our knowledge, it is the first time to determine the effect of a complex relationship between the increased $CO_{2}$ concentration and temperature on the growth of Chinese cabbage.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.197-203
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• 2019

This study was carried out to investigate the effect of chlorine water and plasma gas treatment on the quality and microbial control of Latuca indica L. baby Leaf during storage. Latuca indica L. baby leaves were harvested from a plant height of 10cm. They were sterilized with $100{\mu}L{\cdot}L^{-1}$ chlorine water and plasma-gas (1, 3, and 6hours), and packaged with $1,300cc{\cdot}m^{-2}{\cdot}day^{-1}{\cdot}atm^{-1}$ films and then stored at $8{\pm}1^{\circ}C$ and RH $85{\pm}5%$ for 25days. During storage, the fresh weight loss of all treatments were less than 1.0%, and the carbon dioxide and oxygen concentrations in packages were 6-8% and 16-17%, respectively for all treatments in the final storage day. The concentration of ethylene in the packages fluctuated between $1-3{\mu}L{\cdot}L^{-1}$ during the storage and the highest concentration of ethylene was observed at 6 hours plasma treatment in the final storage day. The off-odor of all treatments were almost odorless, the treatments of chlorine water and 1 hour plasma maintained the marketable visual quality until the end of storage. Chlorophyll content and Hue angle value measured at the final storage day were similar to those measured before storage in chlorine water and 1 hour of plasma treatments. E. coli was not detected immediately after sterilization in all sterilization treatments. After 6 hours of plasma treatment, the total bacteria fungus counts were lower than the domestic microbial standard for agricultural product in all sterilization treatments. The total aerobic counts in the end storage day increased compared to before storage, whereas E. coli was not detected in all sterilization treatments. The sterilization effect against bacteria and fungi was the best in chlorine water treatment. Plasma treatment showed sterilization effects, but within a prolonged period of time. In addition, the sterilization effect decreased gradually. These results suggest that chlorine water and plasma treatment were effective in maintaining Latuca indica L. baby Leaf commerciality and controlling microorganisms during postharvest storage.

• The korean journal of orthodontics
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• v.38 no.4
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• pp.275-282
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• 2008

Objective: The purpose of this study was to investigate the effect of using laser for ceramic bracket bonding of porcelain surfaces and to compare it with conventional treatment of porcelain surfaces. Methods: Ninety feldspathic porcelain specimens were divided into 9 groups of 10, with each group having different surface treatments performed. Surface treatment groups were orthophosphoric acid, orthophosphoric acid with silane, hydrofluoric acid, hydrofluoric acid with silane, sandblasted, sandblasted with silane, laser etched, laser etched with silane, and glazed surface served as a control group. In the laser etched groups, the specimens were irradiated with 2-watt superpulse carbon dioxide ($CO_2$) laser for 20 seconds. Ceramic brackets were bonded with light-cure composite resin and all specimens were stored in water at $37^{\circ}C$ for 24 hours. Shear bond strength was determined in megapascals (MPa) by shear test at 1 mm/minute crosshead speed and the failure pattern was assessed. For statistical analysis, one-way ANOVA and tukey test were used. Results: Statistical analysis showed significant differences between the groups. The HFA + S group showed the highest mean shear bond strength ($13.92{\pm}1.94\;MPa$). This was followed by SB + S ($10.16\;{\pm}\;1.27\;MPa$), HFA ($10.09\;{\pm}\;1.07\;MPa$), L + S ($8.25\;{\pm}\;1.24\;MPa$), L ($7.86\;{\pm}\;0.96\;MPa$), OFA + S ($7.22\;{\pm}\;1.09\;MPa$), SB ($3.41\;{\pm}\;0.37\;MPa$), OFA ($2.81\;{\pm}\;0.37\;MPa$), G ($2.46\;{\pm}\;1.36\;MPa$), Bond failure patterns of HFA and silane groups, except L + S, were cohesive modes in porcelain while adhesive failure was observed in the control group and the rest of the groups. Conclusions : A 2-watt superpulse $CO_2$ laser etching of porcelain surfaces can provide a satisfactory result for porcelain surface treatment for ceramic bracket bonding. Laser irradiation may be an alternative conditioning method for the treatment of porcelain surfaces.

• Food Science and Preservation
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• v.24 no.3
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• pp.351-360
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• 2017

We have studied the technology to extend the storage period of 'Seolhyang' strawberries using modified atmosphere package (MAP) and ethyl pyruvate (EP) treatment for domestic distribution and export. The selected ripe strawberries harvested on December 28, 2016 at the Sancheong farmhouse were transported to the laboratory for 2 h and tested. After a day's precooling at $4^{\circ}C$, the strawberries were divided into seven experimental groups. These groups were control, active MAP using low density polyethylene (LDPE), active MAP using polyamide (PA), active MAP using PA with EP treatment, passive MAP using LDPE, passive MAP using PA and passive MAP using PA with EP treatment. Quality analysis was carried out every 4 days during the storage period of 16 days. During the storage period of 16 days, MAP decreased from 3.5% to less than 1.1% in weight loss ratio compared with control, and decreased from 36% to less than 7% in fungal incidence. In the case of fungi in the EP treatment group, hyphae did not grow on the outside of the strawberry but grew to the inside. This tendency was similar to that in the low oxygen and high carbon dioxide environment of the MAP, the mycelium of the fungus did not grow outside of the strawberry. Fungi are the biggest problem in the distribution and export of strawberries, and these results suggest that MAP alone could inhibit mold and increase shelf life.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.448-454
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• 2021

This study was conducted to the effect of low air temperature and light intensity conditions on yield and quality of tomato at the early stage of growth in Korea. Inplastic greenhouses, low temperature and low temperature with shade treatments were performed from 17 to 42 days after plant. Tomato growing degree days were decreased 5.5% due to cold treatment during the treatment period. Light intensity decreased 74.7% of growing degree days due to shade. After commencing treatments, the plant growth decreased by low temperature and low radiation except for height. Analysis of the yield showed that the first harvest date was the same, but the yield of the control was 3.3 times higher than low temperature with shade treatment. The cumulative yields at 87 days after transplanting were 1734, 1131, and 854 g per plant for control, low temperature, and low temperature with shade, respectively. The sugar and acidity of tomatoes did not differ between treatment and harvesting season. To investigate the photosynthetic characteristics according to the treatment, the carbon dioxide reaction curve was analyzed using the biochemical model of the photosynthetic rate. The results showed that the maximum photosynthetic rate, J (electric transportation rate), TPU (triose phosphate utilization), and R_d (dark respiration rate) did not show any difference with temperature, but were reduced by shading. Vcmax (maximum carboxylation rate) was decreased depending on the low temperature and the shade. Results indicated that low temperature and light intensity at the early growth stage can be inhibited the growth in the early stage but this phenomenon might be recovered afterward. The yield was reduced by low temperature and low intensity and there was no difference in quality.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.267-277
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• 2023

This study is in order to the effect of 1-methlycyclopropene (1-MCP) treatment and film package as modified atmosphere packaging (MAP) on the changes in fruit quality factors of 'Daehong' peaches during cold storage. The concentrations of 1-MCP were treated at 1µL·L^-1 and 2µL·L^-1, and peaches in film package were stored for 28 days in cold storage at 5±1℃ and 85±5% RH. The fruits stored carton box were used as a control of MAP, and 1-MCP free fruits were used as the control of both packages. Rate of fresh weight loss during storage was not significantly different between groups with and without 1-MCP treatment, but was higher in the box package than in the MAP. The control group had a higher incidence of both gases with the 1-MCP treatment group showing statistically significantly low. Carbon dioxide in the package was lowered by about 12% compared to the non-treated group, and the ethylene concentration was maintained at 1µL·L^-1, showing a significance low compared to other treated groups. As the storage period elapsed, the firmness of 1-MCP and MAP treated fruits remained significant at 5-9% compared to the control group. Regardless of the packaging method Hunter a^* values of exocarp and mesocarp were significantly higher in fruit treated with 1-MCP 1µL·L^-1 treatment than in the control group, and anthocyanin was significantly higher in the fruit during the storage period, especially high in MAP. In summary, fruits of MAP group with 1-MCP 1µL·L^-1 had rate of lower respiration and ethylene production, and little changes in firmness, Hunter a^* values of exo-carp and meso-carp, and anthocyanin, which is considered the most suitable method for preserving postharvest quality of the peach cultivar during the storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.592-601
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• 2015

Rubus coreanus is known as Korean black raspberry, native to Korea, Japan, and China. Preliminary studies evaluating their potential for cancer treatment in mammalian test systems are ongoing. In recent years, interest has been renewed due to their high levels of anthocyanins. Anthocyanins in black raspberry are important due to their potential health benefits as dietary antioxidant, anti-inflammatory compound, and as a chemopreventive agent. In the present study, Saccharomyces cerevisiae BA29 was isolated from black raspberry fruit and fruit juice as a biogenic amine non-producing strain for manufacturing of black raspberry wine, after which we investigated its characteristics: biogenic amine-producing ability, cell growth ability, alcohol-fermentation ability, and resistance to alcohol, glucose, and sulfur dioxide. Based on preliminary experiments, we optimized culture medium compositions for improving dried cell weight of S. cerevisiae BA29 by response surface methodology (RSM) as a statistical method. Design for RSM used a central composite design, and molasses with the industrial applicability was used as a carbon source. Through statistical analysis, we obtained optimum values as follows: molasses 200 g/L, peptone 30 g/L, and yeast extract 40 g/L. For the model verification, we confirmed about 3-fold improvement of dried cell weight from 6.39 to 20.9167 g/L compared to basal yeast peptone dextrose medium. Finally, we manufactured black raspberry wine using S. cerevisiae BA29 and produced alcohol of 20.33%. In conclusion, S. cerevisiae isolated from black raspberry fruit and juices has a great potential in the fermentation of black raspberry wine.

• Journal of Animal Science and Technology
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• v.45 no.6
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• pp.1061-1066
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• 2003

The present study was performed to investigate the effect of ozonation of the swine nursery building on indoor air quality and growth efficiency of the weanling piglets. Forty 21-day-old, cross-bred weanling piglets were housed in two ozonated or unozonated pens(10 males and 10 females per pen) for 3 wk alternately in a swine nursery building and this procedure was repeated three times. Ozone was generated using a commercial apparatus outside the nursery building and infused into the nursery building through a duct at a level of 0.03 ppm. Indoor concentrations of harmful gases were measured at 2-h intervals for a 24-h period per each 3-wk feeding trial. Indoor ammonia and carbon dioxide gas concentrations were reduced by the ozonation(P〈0.01) by 21% and 7%, respectively, compared with those of the control(unozonation), although hydrogen sulfide concentration was not affected by the treatment. However, the weight gain, feed intake and feed/gain of the piglets did not change due to the ozonation. Results suggest that ozonation of the swine nursery building is effective for improving the indoor air quality without affecting the production efficiency of weanling piglets.

• Journal of Veterinary Clinics
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• v.27 no.6
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• pp.668-673
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• 2010

This study was to evaluate the effects of tramadol and medetomidine administration on minimum alveolar concentration (MAC) of isoflurane in dogs. MAC of isoflurane was determined in four occasions; 1 ml saline (Control), $2{\mu}g$/kg medetomidine (M2), 4 mg/kg tramadol (T4), $2{\mu}g$/kg medetomidine-4 mg/kg tramadol combination (M2T4). Heart rate, blood pressure, respiratory rate, end-tidal carbon dioxide concentration, saturation of hemoglobin with oxygen and body temperature were recorded. After administration of M2 ($0.81{\times}0.18%$), T4 ($0.81{\times}0.14%$) and M2T4 ($0.62{\times}0.12%$), less isoflurane was required than the control value ($1.13{\times}0.19%$). Significantly lower heart rate than the control value was detected after treatment of M2, T4, and M2T4. When only M2T4 was administered, blood pressure was significantly higher than the control value. In conclusion, administrations of tramadol, medetomidine and medetomidine-tramadol combination decreased the MAC of isoflurane in dogs. Especially, medetomidine-tramadol combinations could be useful as a premedication because of the anesthetic sparing effect and moderate changes in cardiovascular system.