• Journal of Life Science
• /
• v.33 no.7
• /
• pp.538-548
• /
• 2023

The research has been conducted on the isolation of antimicrobial compounds from plant natural extracts and their potential application in oral health care products. This study aimed to investigate the antimicrobial mechanism by analyzing the changes in gene expression of Streptococcus mutans, a major oral pathogen, in response to complex compounds extracted from Aralia continentalis and Arctii Semen using organic solvents. Transcriptome analysis (RNA-seq) revealed that both natural extracts commonly upregulated or downregulated the expression of various genes associated with different metabolic and physiological activities. Three genes (SMU_1584c, SMU_2133c, SMU_921), particularly SMU_921 (rcrR), known as a transcription activator of two sugar phosphotransferase systems (PTS) involved in sugar transport and biofilm formation, exhibited consistent high expression levels. Additionally, component analysis of the A. continentalis extract was performed to compare its effects on gene expression changes with the A. Semen extract, and two active compounds were identified through gas chromatography-mass spectrometry (GC-MS) analysis of the active fraction. The n-hexane fraction (ACEH) from the A. continentalis extract exhibited antibacterial specificity against S. mutans, leading to a significant reduction in the viable cell counts of Streptococcus sanguinis and Streptococcus gordonii among the tested multi-species bacterial communities. These findings suggest the broad-spectrum antibacterial activity of the A. continentalis extract and provide essential foundational data for the development of customized antimicrobial materials by elucidating the antibacterial mechanism of the identified active compounds.

• Analytical Science and Technology
• /
• v.19 no.2
• /
• pp.155-162
• /
• 2006

In this study, a series of experiments were conducted using a standard solution containing ${\alpha}$ and ${\beta}$-endosulfan to follow the removal effect of residual pesticides on soil and aqueous solution. An analytical method for residual pesticides was established by a gas chromatography equipped Ultra II[$(30m{\times}0.25mm(ID){\times}0.25{\mu}m$] capillary column and a ${\mu}$-electron capture detector(${\mu}$-ECD). Recovery rates of residual pesticides for soil samples were 96-100%. The amount of ${\alpha}$ and ${\beta}$-endosulfan that was spread in the soil was checked for various period of time. It indicated that the amount was reduced to 73 and 61%, respectively. When the water spread amount increased from 10 to 100 mL, ${\alpha}$-endosulfan was eliminated from 45 to 85% and while ${\beta}$-endosulfan from 44 to 88%. Removal rates of ${\alpha}$-endosulfan and ${\beta}$-endosulfan were 99% and 98% respectively within 30 minutes. It was assumed that the organic salts and strong alkali elements contained in the pesticide degradator hydrolyzed the residual pesticide.

• Analytical Science and Technology
• /
• v.19 no.3
• /
• pp.255-262
• /
• 2006

In this study, we attempted to evaluate the sorptive loss of VOC upon their contact with different material surfaces including clothing pieces. For the purpose of this study, we developed a method to evaluate such loss by employing a filter holder pack in the thermal desorption line of the GC/FID system. The calibration curves of different aromatic VOCs including benzene, toluene, and xylene were made by loading them at different quantities through the analytical line. A series of experiments were conducted repetitively to draw calibration data sets for all three materials covering glass fiber, cotton, and nylon. The results were then compared in terms of both material types and of VOC types. The extent of sorptive loss increased in a highly systematic manner across different materials such as glass fiber, cotton, and nylon. The patterns of sorptive loss also increased gradually across VOC type such toward in the direction of increasing molecular weights: benzene, toluene, and xylene. According to this experimental study, it is concluded that sorptive behavior of pollutint compounds like VOC can be controlled by the combined effects of both chemical properties and material characteristics.

• Analytical Science and Technology
• /
• v.20 no.4
• /
• pp.347-354
• /
• 2007

A simple and rapid high-performance liquid chromatography assay for the determination of residual novobiocin levels in bovine, porcine, chicken, flatfish and japanese eel muscle has been developed and validated. The separation condition for HPLC/UV was optimized with phenyl hexyl ($4.6{\times}150mm$, $5{\mu}m$) column with 10 mM monobasic sodium phosphate buffer (pH 2.5)/acetonitrile (50/50, v/v) as the mobile phase at a flow rate of 1.0 mL/min and detection wavelength was set at 254 nm. Residues were extracted from tissue by blending with methanol and lipid materials were removed with n-hexane. Then, the methanol extract was evaporated to dryness under a nitrogen stream, reconstituted in the mobile phase. Aliquot of the organic extract was decanted and filtered through $0.45{\mu}m$ syringe filter. The $20{\mu}L$ of the resulting solution was injected into the HPLC system. The calibration ranges were $0.5{\sim}5{\mu}g/g$ and calibration curves were linear with coefficients of correlation better than 0.95. The limits of quantification were $0.5{\mu}g/g$ for all muscles. The recoveries of bovine, porcine, chicken, flatfish and japaneseel muscles were 99.8%, 102.4%, 91.0%, 104.0% and 93.0%, respectively. The procedures were validated according to the CODEX guideline, determining specificity, linearity, accuracy, precision, quantitation limit and recovery.

• Journal of Korea Water Resources Association
• /
• v.57 no.4
• /
• pp.301-310
• /
• 2024

The spatial and temporal non-uniform distribution of precipitation makes water management difficult. Due to climate change, nonuniform distribution of precipitation is worsening, and droughts and floods are occurring frequently. Additionally, the intensity of droughts and floods is intensifying, making existing water management systems difficult. From June 2022 to June 2023, most of the water storage rates of major dams in the Yeongsan river and Seomjin river basin were below 30%. In the case of Juam dam, which is the most dependent on water use in the basin, the water storage rate fell to 20.3%, the lowest ever. Pyeongnim dam recorded the lowest water storage rate of 27.3% on May 4, 2023. Due to a lack of precipitation starting in the spring of 2022, Pyeongnim dam was placed at a drought concern level on June 19, 2022, and entered the severe drought level on August 21. Pyeongrim dam and Suyangje(dam) have different operating institutions. Nevertheless, the low water level was not reached at Pyeongnim dam through organic linkage operation in a drought situation. Pyeongnim dam was able to stably supply water to 63,000 people in three counties. In order to maximize the use of limited water resources, we must review ways to move water smoothly between basins and water sources, and prepare for water shortages caused by climate change by establishing a consumer-centered water supply system.

• Journal of the Korea Safety Management & Science
• /
• v.25 no.4
• /
• pp.45-56
• /
• 2023

This study attempted to provide implications by analyzing the impact of business Owner's safety commitment on industrial accidents and examining the mediating role of management supervisors' safety leadership and worker participation. Analysis was conducted on 2,067 manufacturing sites with 20 to 50 employees in the 10th Occupational Safety and Health Survey data. SPSS waw used to secure the reliability of the measurement variable. Hypothesis vertification was carried out after securing the suitability and validity of the structural model using AMOS. The direct impact of three latent variables on industrial accidents was confirmed: the business owner's safety commitment, the management supervisor's safety leadership, and the worker participation. The employer's safety will and the management supervisor's safety leadership do not directly affect industial accidents, but it has been verified that worker participation has a diret impact on industrial accident reduction. In addition, it has been confirmed that the safety leadership and worker participation of the management. Supervior have a complete mediating effect on the reduction of industrial accidents by mediating with the safety leadership of the management supervior and the participation of the workers. This study analyzed the impact on industrial accidents by dividing the stakeholders constituting the workplace into three classes: business owners, superviors, and workers, but the results suggest that employers and all workers inside the workplace may be organically linked to achieving the goal of reducing industrial accidents. Therefore, in order to establish an autonomous safety management system for safety and health at workerplaces, efforts are needed to reduce industrial accidents in their respective location by forming an organic community among internal stakeholders.

• Journal of Christian Education in Korea
• /
• v.75
• /
• pp.7-31
• /
• 2023

Purpose of study: The purpose of this essay is to seek an alternative direction for confirmation education within the context of Korean Protestant Church, addressing the following issues: 1) Confusion in the use of terminology on confirmation, 2) Superficial understanding of confirmation, and the absence or privatization of confirmation theology, 3) Formalized confirmation education based on the concept of rites of passage, and 4) The absence of denominationally structured confirmation education. Research content and method: To achieve this purpose, this essay attempts to foster an intradisciplinary and interactive dialogue on confirmation through a biblical, historical, and theological approach. Biblically, confirmation is to be understood as the unity of the baptism of water and the baptism of Holy Spirit, associated with the consecration of the baptized as royal priests through the baptism of Holy Spirit. Historically, as a part of the rite of Christian initiation, confirmation was a unified rite that has undergone a process of separation and reunification. Theologically, the rite of confirmation affirms the covenant of the Triune God given in baptism and is positioned between baptism and the Lord's Supper. Conclusions and Suggestions: In conclusion, this essay suggests an alternative form of Confirmation education that is oriented towards the following objectives: 1) Education that forms the identity given in the baptismal covenant, 2) Education that reflects characteristics of both baptism and the Lord's Supper, 3) Education that integrates the Bible, doctrine, and life of confirmand and, 4) Education based on an organic educational system.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.12
• /
• pp.1757-1763
• /
• 2011

The physico-chemical properties of broccoli sprouts cultivated in a plant factory system with different lighting conditions were investigated. We reported that there were significant differences among the chemical and nutritional properties of the broccoli sprouts grown under different light sources. Two kinds of sugars (glucose and fructose) were detected in the plants. The amount of glucose was 2.94~3.12% and that of fructose was 1.54~2.04%. Total chlorophyll was $1,157{\pm}0.004$ mg% and chlorophyll-a $777{\pm}0.01$ mg%. All over the test materials, 2 kinds of organic acids (citric acid and malic acid) were detected. The level of citric acid was 908~1,136 mg% and its highest level was under the (Blue LED) light source. The level of malic acid was 514~834 mg% and its highest level was under the (Red LED) light source. Seven different minerals were also analyzed. The amount of K was 518 mg% and its amount was significantly higher than that of Mg or Na. There were also negligible amounts of Zn, Fe and Cu. The amounts of vitamin A, C and E under the Red LED were, $860.62{\pm}0.02\;{\mu}gRE$, $134.570{\pm}0.14$ mg% and $1.44{\pm}0.1$ IU. The amounts under the Blue LED were, $432.48{\pm}0.05\;{\mu}gRE$, $137.05{\pm}0.1$ mg% and $1.11{\pm}0.12$ IU. The amounts under both Red and Blue LEDs were, $667.33{\pm}0.11\;{\mu}gRE$, $118.50{\pm}0.09$ mg% and $1.47{\pm}0.1$ IU. And finally, the amounts under a White LED were, $640.25{\pm}0.08\;{\mu}gRE$, $119.87{\pm}0.07$ mg% and $1.31{\pm}0.15$ IU. In this study, significant changes were shown in the chemical and nutritional properties of the broccoli sprouts. These findings indicate that LED light sources stimulated germination of the plants.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.1
• /
• pp.66-74
• /
• 2005

This survey was conducted to assess the consumer perceptions of food-related hazard in 500 housewives from all over Korea. The subjects were selected by stratified random sampling method. The survey was performed using structured questionnaire through telephone interview by skilled interviewers. The results showed that 34.6% of the respondents felt secure and were not concerned about food safety, and 65.4% were concerned about food safety. Logistic regression analysis showed that the increasing concern on food brands, food additives (such as food preservatives and artificial color), and imported foodstuffs indicated the current increasing concern on food safety. Other related factors indicating the increasing concern on food safety were education level and care for children's health. The respondents who cared about food safety expressed a high degree of concern on processed foodstuffs such as commercial boxed lunch (93.3%), imported foods (92.7%), fastfoods (89.9%), processed meat products (88.7%), dining out (85.6%), cannery and frozen foods (83.5%), and instant foods (82.0%). The lowest degree of concern was on rice. All the respondents perceived that residues of chemical substances such as pesticides and food additives, and endocrine disrupters were the most potential food risk factors, followed by food-borne pathogens, and GMOs (Genetically Modified Organisms). However, these results were not consistent with scientific judgment. Therefore, more education and information were needed for consumers' awareness of facts and myths about food safety. In addition, the results showed that consumers put lower trust in food products information such as food labels, cultivation methods (organic or not), quality labels, and the place of origin. Nevertheless, the respondents expressed their desire to overcome alienation, and recognized the importance of knowing of the origin or the producers of food. They identified that people who need to take extreme precautions on food contamination were the producers, government officials, food companies, consumers, the consumer's association, and marketers, arranged in the order of highest to lowest. They also believed that the production stage of agriculture was the most important step for improving the level of food safety Therefore, the results indicated that there is a need to introduce safety systems in the production of agricultural products, as follows: Good Agricultural Practice (GAP), Hazard Analysis and Critical Control Point (HACCP), and Traceability System (75).

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.6
• /
• pp.836-842
• /
• 2009

The objectives of this study were to evaluate potential benefits of intercropping of corn with runner bean for a smallsized farming system, based on land equivalent ratio (LER) and silage yield and quality of corn intercropped with runner bean (Phaseolus vulgaris L.), in arid conditions of Turkey under an irrigation system. This experiment was established as a split-plot design in a randomized complete block, with three replications and carried out over two (consecutive) years in 2006 and 2007. Seven different mixtures (runner bean, B and silage corn sole crop, C, 10% B+90% C, 20% B+80% C, 30% B+70% C, 40% B+60%C, and 50% B+50%C) of silage corn-runner bean were intercropped. All of the mixtures were grown under irrigation. The corn-runner bean fields were planted in the second week of May and harvested in the first week of September in both years. Green beans were harvested three times each year and green bean yields were recorded each time. After the 3rd harvest of green bean, residues of bean and corn together were randomly harvested from a 1 $m^{2}$ area by hand using a clipper when the bean started to dry and corn was at the dough stage. Green mass yields of each plot were recorded. Silages were prepared from each plot (triplicate) in 1 L mini-silos. After 60 d ensiling, subsamples were taken from this material for determination of dry matter (DM), pH, organic acids, chemical composition, and in vitro DM digestibility of silages. The LER index was also calculated to evaluate intercrop efficiencies with respect to sole crops. Average pH, acetic, propionic and butyric acid concentrations were similar but lactic acid and ammonia-N levels were significantly different (p<0.05) among different mixtures of bean intercropped with corn. Ammonia-N levels linearly increased from 0.90% to 2.218 as the percentage of bean increased in the mixtures up to a 50:50 seeding ratio. While average CP content increased linearly from 6.47 to 12.45%, and average NDF and ADF contents decreased linearly from 56.17 to 44.88 and from 34.92 to 33.51%, respectively, (p<0.05) as the percentage of bean increased in the mixtures up to a 50:50 seeding ratio, but DM and OM contents did not differ among different mixtures of bean intercropped with corn (p>0.05). In vitro OM digestibility values differed significantly among bean-corn mixture silages (p<0.05). Fresh bean, herbage DM, IVOMD, ME yields, and LER index were significantly influenced by percentage of bean in the mixtures (p<0.01). As the percentage of bean increased in the mixtures up to a 50:50 seeding ratio, yields of fresh bean (from 0 to 24,380 kg/ha) and CP (from 1,258.0 to 1,563.0 kg/ha) and LER values (from 1.0 to 1.775) linearly increased, but yields of herbage DM (from 19,670 to 12,550 kg/ha), IVOMD (from 12,790 to 8,020 kg/ha) and ME (46,230 to 29,000 Mcal/ha) yields decreased (p<0.05). In conclusion, all of the bean-corn mixtures provided a good silage and better CP concentrations. Even though forage yields decreased, the LER index linearly increased as the percentage of bean increased in the mixture up to a 50:50 seeding ratio, which indicates a greater utilization of land. Therefore, a 50:50 seeding ratio seemed to be best for optimal utilization of land in this study and to provide greater financial stability for labor-intensive, small farmers.