Recently, active research in Korea and worldwide has begun to focus on gene function and cultivar development using gene editing tools. This research, in addition to studies on edible mushroom, aims to enhance the physical and biochemical characteristics of mushrooms for applications in materials and substance production. For these studies, efficient isolation of protoplasts from the target mushroom is critical. However, several commercial cell wall-lysing enzyme cocktails, including Novozyme234, Glucanex, and Lysing enzymes, have recently been discontinued. In this study, we aimed to identify alternative enzyme systems to replace the discontinued cell wall-lysing enzymes for stable isolation of protoplasts from Ganoderma lucidum. To select an optimal osmotic buffer, enzyme function in 0.6 and 1.2 M Sorbitol, Sucrose, Mannitol, and KCl was assessed. The effect of reaction time was also evaluated. Protoplast isolation efficiency of each alternative enzyme was tested using lysing enzymes from Trichoderma harzianum, Chimax-N, and Yatalase, either individually or in combination. This matrix of studies identified enzymes and optimal conditions that could replace the discontinued lysing enzymes.

구절초(Chrysanthemum zawadskii var. latilobum (Maxim.) Kitam.)는 linarin, chlorogenic acid 등의 유용성분들을 함유하고 있으며, 산업적으 로 이용가치가 있는 식물이다. 구절초의 산업화를 위해 유용성분인 linarin과 chlorogenic acid의 최적 추출 조건을 구하기 위해 반응표면분석을 수행하였으며, Linarin의 최적 추출 조건은 에탄올 농도 100%, 추출 시간 30h, 추출 온도 75℃였다. 최적 추출 조건에서 예상된 linarin의 값은 33.36 mg/g였으며 실험값은 38.33±2.66 mg/g였다. Chlorogenic acid의 최적 추출 조건은 에탄올 농도 48%, 추출 시간 30h, 추출 온도 65℃로 예상된 chlorogenic acid의 함량은 42.19 mg/g였으며 실험값은 44.34±2.09 mg/g이었다. 반응표면분석법으로 도출된 최적 추출 조건을 통해 구절초에서 linarin과 chlorogenic acid의 효율적인 추출이 가능함을 확인하였다.

Environmental pollution has led to global warming, which threatens human life. In response, hydrogen is gaining attention as a next-generation energy source that does not emit carbon. Due to its explosive nature, special care must be taken in the safe storage and transportation of hydrogen. Among various storage methods, liquefied storage, which can reduce its volume to 1/800, is considered efficient. However, since its boiling point reaches -253°C, the design of an insulation system is essential. For the design of insulation systems applied to large containers, a membrane-type design is required, which necessitates the use of cryogenic adhesives. To evaluate whether the cryogenic adhesive is properly implemented, assessments such as tensile and shear tests are necessary. This study presents a methodology for shear evaluation. Conventional methods for shear evaluation of adhesives result in slippage, preventing proper assessment. Therefore, a method involving drilling holes in the gripper and pulling from the holes must be applied. Optimal design concerning the size and location of the holes is required, and this study derives optimal values based on finite element analysis. By conducting experiments based on the results of this study, it is expected that the risk of gripper damage will be minimized, allowing for accurate evaluation of the adhesive’s performance.

Wastewater management is increasingly emphasizing economic and environmental sustainability. Traditional methods in sewage treatment plants have significant implications for the environment and the economy due to power and chemical consumption, and sludge generation. To address these challenges, a study was conducted to develop the Intermittent Cycle Extended Aeration System (ICEAS). This approach was implemented as the primary technique in a full-scale wastewater treatment facility, utilizing key operational factors within the standard Sequencing Batch Reactor (SBR) process. The optimal operational approach, identified in this study, was put into practice at the research facility from January 2020 to December 2022. By implementing management strategies within the biological reactor, it was shown that maintaining and reducing chemical quantities, sludge generation, power consumption, and related costs could yield economic benefits. Moreover, adapting operations to influent characteristics and seasonal conditions allowed for efficient blower operation, reducing unnecessary electricity consumption and ensuring proper dissolved oxygen levels. Despite annual increases in influent flow rate and concentration, this study demonstrated the ability to maintain and reduce sludge production, electricity consumption, and chemical usage. Additionally, systematic responses to emergencies and abnormal situations significantly contributed to economic, technical, and environmental benefits.

This study was performed to investigate antioxidant and anti-inflammatory activities of perilla(Perilla frutescens L.) seed, flower and leaf according to extraction condition. Perilla seed extracts(PSE), perilla flower extracts(PFE), perilla leaf extracts(PLE) was extracted by stirring extraction (STE, 25°C), shaking extraction (SHE, 80°C), and sonication assisted extraction(SAE, , 25°C) with 94% ethanol, 60% ethanol and distilled water, followed by analysis of total polyphenol and flavonoid and testing radical scavenging activities. The highest total polyphenol content (5.47, 9.36, 38.58 mg gallic acid equivalent/g), total flavonoid content(5.77, 8.62, 46.44 mg catechin equivalent/g), ABTS(10.68, 19.46, 63.56 mg trolox equivalent/g) and DPPH(6.51, 7.69, 79.73 mg trolox equivalent/g) radical scavenging activity of PSE, PFE and PLE was observed in the HWE with 60% ethanol,. Among the three extraction method, SHE provided the best results for yield, polyphenol, flavonoid content of perilla seed, flower, leaf in comparison to STE or SAE. SHE with 60% ethanol of perilla seed, flower, leaf more effectively inhibited secretion of nitric oxide(NO) and pro-inflammatory cytokine in RAW 264.7 macrophage exposed to LPS compared to other extraction solvent and method. Therefore, these extracts obtained from perilla seed, flower, leaf could be used antioxidant and anti-inflammatory ingredients in the food industry.

Protein is an essential nutrient for humans to sustain life, but it is predicted that it will be challenging to secure protein through the traditional livestock industry in the future. Microalgae has high future value as an alternative protein food source due to resource utilization and sustainability advantages. In order to increase productivity, the culture conditions of microalgae, Chlorella vulgaris, Dunaliella salina, and Scenedesmus obliquus were examined in this study. The optimal culture conditions of C. vulgaris were mixotrophic culture, 25oC culture temperature, 7.0 initial pH, 10% initial inoculation, stirring culture, 3000 Lux light intensity, and 24L:0D light/dark cycle period with red LED. For D. salina, the optimal culture conditions were mixotrophic culture, 20oC culture temperature, 8.0 initial pH, 10% initial inoculation, stirring culture, 6000 Lux light intensity, and 12L:12D light/dark cycle period with white LED. For S. obliquus, the optimal culture conditions were mixotrophic culture, 30oC culture temperature, 8.0 initial pH, 10% initial inoculation, stirring culture, 4500 Lux light intensity, and 14L:10D light/dark cycle period with fluorescent light. These findings can be used as important information for increasing the production of microalgae as an alternative protein material resource in the future.

프로바이오틱스 제품에 대한 수요가 지속적으로 증가하 고 있으며, Lactobacillus 균주가 가장 대중적인 프로바이 오틱스로 널리 사용되고 있다. 프로바이오틱스는 기준에 적합한 균수의 확보가 중요하며 제조원가나 시간 등을 낮 추기 위해 배양법의 개발이 필요하므로 Lactobacillus 생 산을 위한 배양 조건이 최적화되었다. 반응표면방법론에 의한 통계적 최적화에서 반응 변수에 영향을 미치는 독립 변수의 최적 조건은 Lactobacillus acidophilus의 경우 22.55 시간(배양시간), 25oC(배양온도), 3.41%(프리바이오틱스 농 도); Lactiplantibacillus plantarum의 경우 24시간, 30.86oC, 2.00%; Lacticaseibacillus rhamnosus의 경우 66.67시간, 35oC, 3.41%이었다. Lactobacillus의 최적 배양조건은 예측 한 결과와 실제 결과가 밀접하게 일치하는 것을 확인하였 다. 이러한 데이터는 수율 높은 Lactobacillus를 생산하는 데 중요한 포인트를 제공할 것이다.

As the capacity of renewable power generation facilities rapidly increases, the variability of electric power system and gas turbine power generation is also increasing. Therefore, problems may occur that require urgent repair while the gas turbine rotor is stopped. When the gas turbine rotor turning is stopped and then restarted, if the turning period is not appropriate, severe vibration may occur due to rotor bending. As a result of the experiment, it was confirmed that normal operation is possible when the gap data measured at the start of rotor turning after maintenance work is similar to the existing value. And the vibration value at the start of rotor turning was lower as the rotor temperature was lower or the stop period was shorter.

본 논문에서는 한국전통게임에 사용되는 접이식 종이구조물(이하 딱지)의 접이과정을 모델링하고 게임의 승리조건을 만족시키는 충돌조건을 유전알고리즘을 이용하여 산정하는 과정을 서술하였다. 딱지는 A4용지 2장으로 구성되는 것을 가정하였다. 접이과정은 강제경계조건을 부여하여 날개부분을 꼬임의 위치로 변형시키고 강체판의 강제경계조건을 이용하여 딱지를 압착하였다. 이후 복원 력에 의한 완화해석을 수행하여 게임에 사용된 딱지의 형상과 응력상태를 구성하였다. 얻어진 동일한 2개의 딱지 중 타격딱지를 주어 진 충돌위치로 강제변위에 의해서 이동시키고 주어진 충돌속력에 대한 충돌해석으로 게임의 진행과정을 해석하였다. 이 때 승리조건 인 피격딱지의 반전을 일으키는 충돌조건을 산정하기 위하여 유전알고리즘을 이용한 최적화해석을 수행하였다. 이 과정에서 효율적 인 해석을 위하여 충돌해석을 2단계로 나누고 1단계의 해석결과 피격딱지에 반전이 발생할 가능성이 있는 경우에만 2단계해석을 진 행하였다. 1단계 해석에서 유전알고리즘의 적합함수는 피격딱지의 방향코사인이었고 2단계해석에서는 속도의 역수로 하여 전체적 으로는 가장 낮은 충돌속력을 가지는 충돌조건을 찾아내고자 하였다. 해석수행결과 다양한 압착두께에 따른 최적의 충돌조건을 찾아 낼 수 있었다.

한국에서 알스트로메리아(Alstroemeria)는 저온 작물로 난 방비 절감 효과가 있고 장식용 절화 소재로 꾸준히 소비되어, 일정 재배면적이 유지되고 있다. 본 연구는 알스트로메리아 ‘한에로스’의 기내 대량증식과 뿌리 발근 조건을 구명하고 무 균묘 생산 시스템을 구축하기 위해 수행했다. 기내 대량 증식 조건 구명 실험에는 Murashige and Skoog(MS) 배지(3% sucrose, 0.25% gelrite)에 BA 단용 처리(BA 0.25, 0.5, 0.75mg･L-1)와 NAA 0.2mg･L-1에 BA를 농도(BA 0.25, 0.5, 0.75mg･L-1)에 따라 혼용 처리하였다. 발근 조건 구명을 위 해 MS배지(3% sucrose, 0.25% gelrite)에 BA 0.25 mg･L-1 단용 처리와 BA 0.25mg･L-1에 NAA를 농도(NAA 0.1, 0.2, 0.3mg･L-1)에 따라 혼용 처리하였다. 뿌리줄기 증식 실험 결 과, 호르몬 첨가에 따른 생육차이는 뿌리줄기 수를 제외한 나 머지 부분에서 뚜렷하게 확인되었다. 단용 처리구 보다 혼용 처리구에서 많은 신초가 유도되었다. BA 0.5mg･L-1와 NAA 0.2mg･L-1 혼용 배지에서 가장 많은 1.43개의 신초가 유도되 었다. 발근 실험 결과, ‘한에로스’는 BA 0.25mg･L-1 와 NAA 0.3mg･L-1 혼용 배지에서 뿌리 수가 3.96개로 가장 많고, 뿌 리가 짧고 두꺼워 순화 과정 중에 뿌리 손실이 적었다. 또한, 순화 과정 중 묘가 고사하지 않았다. 종합적으로, ‘한에로스’ 는 BA 0.5mg･L-1와 NAA0.2 mg･L-1 혼용 배지에서 증식을 하는 것이 적절하며, BA 0.25mg･L-1와 NAA 0.3mg･L-1 혼 용 배지에서 발근 후 순화하는 것이 최적의 기내 배양 조건으 로 사료된다. 본 연구의 결과로 알스트로메리아 무균묘의 보 급 확대에 기여하고자 한다.

Dongchimi is one of the most representative types of watery kimchi in Korea. Although the scope of application of dongchimi has been expanded, research on the quality of dongchimi is insufficient compared to that of baechu kimchi. This study aimed to find the optimal manufacturing condition of high-acidity dongchimi and investigate the effects of potassium citrate (P) and sugar (S) on quality. Different dongchimi samples (Control, S, P) were prepared and stored at 15oC for 15 days. Among the various sugars, sucrose made the highest acidity of dongchimi. When potassium citrate was added as a pH buffer, the acidity was 2.2 times higher than the control group. In the PS group, where sucrose and potassium citrate were added, the acidity and organic acid content were 3-fold and 3.7-fold higher, respectively, than those in the control group. As a result of the analysis of the free sugar content, the metabolism of lactic acid bacteria was expected to be relatively more activated in the PS group. Therefore, this study could be utilized in the dongchimi manufacturing industry or as primary data for other dongchimi research.

In this study, a new type of composite material combined with carbonyl iron, a relatively strong ferromagnetic material, was prepared to overcome the current application limitations of Prussian blue, which is effective in removing radioactive cesium. The surface of the prepared composite was analyzed using SEM and XRD, and it was confirmed that nano-sized Prussian Blue was synthesized on the particle surface. In order to evaluate the cesium removal ability, 0.2 g of the composite prepared for raw cesium aquatic solution at a concentration of 5 μg was added and reacted, resulting in a cesium removal rate of 99.5 %. The complex follows Langmuir’s adsorption model and has a maximum adsorption amount (qe) of 79.3 mg/g. The Central Composite Design (CCD) of the Response Surface Method (RSM) was used to derive the optimal application conditions of the prepared composite. The optimal application conditions achieved using Response optimization appeared at a stirring speed of pH 7, 17.6 RPM. The composite manufactured through this research is a material that overcomes the Prussian Blue limit in powder form and is considered to be excellent economically and environmentally when applied to a cesium removal site.

The carbon concentration in the carburized steels was measured by electron probe microanalysis (EPMA) for a range of soluted carbon content in austenite from 0.1 to 1.2 wt%. This study demonstrates the problems in carbon quantitative analysis using the existing calibration curve derived from pure iron (0.008 wt%C) and graphite (99.98 wt%C) as standard specimens. In order to derive an improved calibration curve, carbon homogenization treatment was performed to produce a uniform Kα intensity in selected standard samples (AISI 8620, AISI 4140, AISI 1065, AISI 52100 steel). The trend of detection intensity was identified according to the analysis condition, such as accelerating voltage (10, 15, 30 keV), and beam current (20, 50 nA). The appropriate analysis conditions (15 keV, 20 nA) were derived. When the carbon concentration depth profile of the carburized specimen was measured for a short carburizing time using the improved calibration curve, it proved to be a more reliable and accurate analysis method compared to the conventional analysis method.