• Korean Journal of Plant Tissue Culture
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• v.21 no.4
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• pp.221-225
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• 1994

This experiment was conducted to identify the optimal in vitro propagation condition of Cnidii rhizoma (Cnidium officinale Makino). It was effective to reduce contamination and improve regeneration of shoot when shoot tips taken in July were cultured in 1/2 strength Murashige and Skoog medium supplemented with 500 mg/L carbenicillin disodium 1.0 mg/L BA and 1.0mg/L $GA_3$followed by surface sterilization of explant source in solution of 1% sodium hypochlorite for 20 minutes. When shoot tips were 쳐cultured in 1/2 strength MS medium with 0.5 mg/L BA and 60 g/L sucrose, shoot elogation and subsequent multiplication of the formed shoot were favorable than in other media. Regenerants were well rooted in 1/2 strength MS medium containing 3.0 mg/L NAA.

• Korean Journal of Environmental Agriculture
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• v.28 no.4
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• pp.403-408
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• 2009

Dandelion (Taraxacum platycarpum) has been widely utilized for medicinal purposes. However, the dandelion seeds are relatively difficult to germinate under cultivation conditions, which hampers seedling propagation of dandelion plants and reduces the opportunity of usage of such a useful medicinal plant. Thus, in this study, in vitro conditions for the dandelion seed germination were optimized to enhance the germination rate. In seed washing steps, the sequential treatments with 20% of ethanol, 20% of NaOCl, and distilled water avoided microbial contamination with the highest in vitro germination rate (67.5%) from seeds sown in germination media. The media supplemented with 1.4 g/L of MS salts and 1% of sucrose significantly enhanced the germination rate compared to the media with 4.4 g/L of MS and 3% of sucrose. Sowing the seeds vertically in the optimized media supplement conditions, 1.4 g/L of MS salts and 1% of sucrose, gave the maximum in vitro germination rate (61%), which was almost three times higher than sowing seeds on a soil pot (23%). Our results indicate that the seed washing and sowing methods including germination medium supplements can be optimized to enhance in vitro seed germination of dandelion.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.13-18
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• 2006

Mandarin juice was processed using a continuous high pressure $CO_2$ system. Response surface methodology was used to investigate the effects of the processing parameters such as temperature, pressure, residence time, and %(w/w) ratio of $CO_2$ to juice on total aerobic count (TAC), pectinesterase (PE) activity, cloud level, $^{\circ}Brix$, pH, and titratable acidity (TA) of the juices. Maximum log reduction (3.47) of TAC was observed at $35^{\circ}C$, 41.1 MPa, 9 min residence time, and 7% $CO_2$. PE was inactivated by 7-51%. The cloud was not only retained but was also enhanced by 38%. Lightness and yellowness increased, and redness decreased. The processing temperature and % $CO_2$/juice ratio significantly affected high pressure $CO_2$ processing of the juice in terms of pasteurization, PE inactivation, cloud increase, and color change. The $^{\circ}Brix$, pH, and TA before and after treatment remained unchanged.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.37-37
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• 2019

Cryopreservation is one of the ideal and suitable methods for long-term storage of plant germplasm. The plant contaminated with diseases and pathogens are decreased the multiplication rate, survival rate and high quality of plants after cryopreservation. The aim of this work was to improve a micropropagation method for lily in Korea, which are cultivars and indigenous plant. In the last process of rinsing scales after surface-sterilization, we tried to control the diseases and pathogens lived within the tissue by rinsing in 0.03% sodium hypochlorite (NaClO) instead of sterile distilled water. Bulb scales of Lilium were cultured in vitro on MS medium supplemented with Plant Preservative Mixture (PPM). The newly small bulb formed from bulb-scales was transferred to MS medium. We checked the non-contamination and survival rate after 2 weeks in culture. Non-contamination was shown to be 70 to 90% in formed small bulbs. This study will help to mitigate microbial contamination in Lilium species micropropagation for cryopreservation.

• The Plant Pathology Journal
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• v.31 no.4
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• pp.343-349
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• 2015

Citrus canker caused by Xanthomonas citri subsp. citri (Xcc) is one of the most important bacterial diseases of citrus. Because citrus canker is not found in many countries including European Union and Australia, Xcc is strictly regulated in order to prevent its spread. In this study, the effects of X-irradiation on Xcc growth either in the suspension or on the surface of citrus fruits were investigated. The suspension containing $1{\times}10^7cfu/ml$ of Xcc was irradiated with different absorbed doses of X-irradiation ranging from 50 to 400 Gy. The results showed that Xcc was fully dead at 400 Gy of X-irradiation. To determine the effect of X-irradiation on quarantine, the Xcc-inoculated citrus fruits were irradiated with different X-ray doses at which Xcc was completely inhibited by an irradiation dose of 250 Gy. The $D_{10}$ value for Xcc on citrus fruits was found to be 97 Gy, indicating the possibility of direct application on citrus quarantine without any side sterilizer. Beside, presence of Xcc on the surface of asymptomatic citrus fruits obtained from citrus canker-infected orchards was noted. It indicated that the exporting citrus fruits need any treatment so that Xcc on the citrus fruits should be completely eliminated. Based on these results, ionizing radiation can be considered as an alternative method of eradicating Xcc for export of citrus fruits.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.4
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• pp.320-326
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• 2019

Recently, the application of atmospheric plasma technology in air filtration is increasing. Sterilization by an atmospheric plasma device is very effective. However, ozone gas, which is generated during atmospheric plasma formation, poses a hazard to human health. To reduce the ozone gas during plasma discharge, we fabricated a one-plate hybrid plasma discharge device with a heating element, which can decompose ozone gas effectively by a simple heating action. In this study, we evaluated the plasma discharge characteristics and ozone concentrations with various Ar flow rates and temperatures. With increasing Ar gas flow rate, the ozone concentration and spectrum intensity increased till an Ar gas flow rate of 60 sccm, and decreased thereafter. When discharged in high temperature, the ozone concentration and spectrum intensity decreased. Further, to evaluate the state of the treated surface under various plasma discharge and heating conditions, we measured the variation in the contact angles on the surface. Regardless of the temperature, the contact angle increased with increasing discharge voltage. However, the contact angle increased when discharged at high temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.2
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• pp.262-266
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• 1983

Influence of fungi living on the endocarp surface of depulped seeds of Panax ginseng on the dehiscence was investigated with a fungicidal treatment of the seeds and sterilization of the sand at the beginning of stratification. 1. Isolation frequency of the fungi living on the endocarp surface of de-pulped seed was reduced and hardness of the endocarp did not change significantly in seed treated with a fungicide Captan wp. 50%. A significant negative correlation $(r=-0.984^**)$ was found between the frequency of fungi isolation and the hardness of the endocarp. 2. Increase of water content in the seed treated with the fungicide was delayed 20days compared to the untreated. 3. Growth of the embryo and dehiscence of the seed was suppressed by the fungicide treatment. The length of the embryo was inversely proportional to the hardness of the seed. It is suggested that the fungi facilitate the softening of the endocarp thereby enhancing the supply of oxygen and water necessary for the embryo development, therefore, accelerate the growing of embryo and cause the dehiscence.

• Journal of the Korean institute of surface engineering
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• v.56 no.3
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• pp.208-218
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• 2023

Photocatalysts are advanced materials which accelerate the photoreaction by providing ordinary reactions with other pathways. The catalysts have various advantages, such as low-cost, low operating temperature and pressure, and long-term use. They are applied to environmental and energy field, including the air and water purification, water splitting for hydrogen production, sterilization and self-cleaning surfaces. However, commercial photocatalysts only absorb ultraviolet light between 100 and 400 nm of wavelength which comprises only 5% in sunlight due to the wide band gap. In addition, rapid recombination of electron-hole pairs reduces the photocatalytic performance. Recently, studies on blackening photocatalysts by laser, thermal, and plasma treatments have been conducted to enhance the absorption of visible light and photocatalytic activity. The disordered structures could yield mid-gap states and vacancies could cause charge carrier trapping. Herein, liquid phase plasma (LPP) is adopted to synthesize Ag-doped black ZnO for the utilization of visible-light. The physical and chemical characteristics of the synthesized photocatalysts are analyzed by SEM/EDS, XRD, XPS and the optical properties of them are investigated using UV/Vis DRS and PL analyses. Lastly, the photocatalytic activity was evaluated using methylene blue as a pollutant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.3
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• pp.275-283
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• 2023

This study optimized the vegetable rice porridge preparation process with Israeli carp Cyprinus carpio (VRP-IC). The optimum heating period for Israeli carp paste (IC-P) in a retort was 120 min as per yield results. Response surface methodology was performed with IC-P/[rice (glutinous rice: non-glutinous rice=6:4) (Rice, RI)+vegetable (carrot: zucchini=1:1) (vegetable, VE)] (X₁) and RI/VE (X₂) as independent variables; viscosity (Y₁), hardness (Y₂), amino nitrogen (Y₃), and overall sensory acceptance (Y₄) as dependent variables. Optimum rates of IC-P, RI, and VE were 47.37%, 24.49%, and 28.15%, respectively; predicted multiple response optimum values for the dependent variables were 20,150 mPa·s, 2,002.9 N/m2, 193.1 mg/100 g, and a 6.4 score for Y₁, Y₂, Y₃, and Y₄, respectively. Under optimum conditions, experimental values for Y₁, Y₂, Y₃, and Y₄ were 20,359.8±191.9 mPa·s, 2,015.0±9.6 N/m2, 188.1±4.9 mg/100 g, and a 6.5±0.2 score, respectively, which were not significantly different from the predicted values (P < 0.05). Results of F0 value, viscosity, hardness, volatile odor intensity, and browning suggested that the optimum sterilization period was 25 min. VRP-IC prepared under the optimum conditions was superior to commercial vegetable rice porridges in sensory evaluations.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.3
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• pp.178-188
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• 2017

Purpose: We compared the effects of newly developed diode laser (Bison 808 nm Diode laser) on the treatment of peri-implantitis with conventional products (Picasso 810 nm Diode laser) by comparing the surface temperature of titanium disc and bacterial sterilization according to laser power. Materials and Methods: The titanium disc was irradiated for 60 seconds and 1 - 2.5 W using diode laser 808 nm and 810 nm. The surface temperature of the titanium disc was measured using a temperature measurement module and a temperature measurement program. In addition, in order to investigate the sterilizing effect according to the laser power, 808 nm laser was irradiated after application of bacteria to sandblasted large-grit acid-etched (SLA) and resorbable blast media (RBM) coated titanium discs. The irradiated disks were examined with scanning electron microscopy. Results: Both 808 nm and 810 nm lasers increased disk surface temperature as the power increased. When the 810 nm was irradiated under all conditions, the initial temperature rise rate, the descending rate, and the temperature change before and after was higher than that of 808 nm. Disk surface changes were not observed on both lasers at all conditions. Bacteria were irradiated with 808 nm, and the bactericidal effect was increased as the power increased. Conclusion: When applying these diode lasers to the treatment of peri-implantitis, 808 nm which have a bactericidal effect with less temperature fluctuation in the same power conditions would be considered safer. However, in order to apply a laser treatment in the dental clinical field, various safety and reliability should be secured.