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        검색결과 212

        1.
        2024.02 KCI 등재 구독 인증기관·개인회원 무료
        Plants synthesize antioxidant compounds as a defense mechanism against reactive oxygen species. Recently, plant-derived antioxidant compounds have attracted attention due to the increasing consumer awareness in the heath industry. However, traditional methods for measuring the antioxidant activity of these compounds are time-consuming and costly. Therefore, our study constructed a quantitative structure-activity relationship (QSAR) model that can predict antioxidant activity using graph convolutional networks (GCN) from plant structural data. The accuracy (Acc) of the model reached 0.6 and the loss reached 0.03. Although with lower accuracy than previously reported QSAR models, our model showed the possibility of predicting DPPH antioxidant activity in a wide range of plant compounds (phenolics, polyphenols, vitamins, etc.) based on their graph structure.
        2.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Hypertension is characterized by excessive renin-angiotensin system activity, leading to blood vessel constriction. Several synthetic compounds have been developed to inhibit renin and angiotensin-converting enzyme (ACE). These drugs often have adverse side effects, driving the exploration of plant protein-derived peptides as alternative or supplementary treatments. This study assessed the phenolic compound and amino acid content and the antioxidant and antihypertensive activity of 5 South Korean staple crops. Sorghum had the highest phenolic compound content and exhibited the highest antioxidant activity. Millet grains, particularly finger millet (38.86%), showed higher antihypertensive activity than red beans (14.42%) and sorghum (17.16%). Finger millet was found to contain a large proportion of branched-chain, aromatic, and sulfur-containing amino acids, which are associated with ACE inhibition. In particular, cysteine content was positively correlated with ACE inhibition in the crops tested (r=0.696, p<0.01). This study confirmed that the amino acid composition was more correlated with the antihypertensive activity of grains than the phenolic compound content. Finger millet mainly contained amino acids, which have higher ACE inhibitory activity, resulting in the strongest antihypertensive activity. These findings underscore the antihypertensive potential of select crops as plant-based food ingredients, offering insight into their biological functions.
        4,200원
        3.
        2023.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Fulvic acid, a humic substance with unique properties, has sparked interest due to its potential applications in the treatment of allergic diseases, Alzheimer's disease, and as a microplastic adsorbent. However, conventional extraction methods produce insufficient quantities for commercial use, which has prompted research to enhance fulvic acid production. In this study, we investigated the impact of Saccharomyces cerevisiae fermentation on the yield and spectral characteristics of fulvic acid extracted from white peat. Fulvic acid was extracted from both S. cerevisiae-treated and untreated white peats using acid precipitation. The yield of fulvic acid from the S. cerevisiae treated group reached its highest at 3.5 % after 72 hr of fermentation, which was significantly higher than the untreated group (1.1 %). Fourier Transform Infrared (FTIR) analysis revealed similarities in functional groups and characteristic absorption bands between the treated and untreated fulvic acid samples. These findings suggest that S. cerevisiae fermentation can increase the yield of fulvic acid extracted from white peat, providing a promising approach for enhancing the commercial viability of fulvic acid production.
        4,000원
        4.
        2023.10 구독 인증기관·개인회원 무료
        본 연구는 주변 환경의 차이에 따른 화분매개곤충의 유입 특성을 파악하기 위하여 국립수목원 내 진화속을걷 는정원과 부추속전문전시원에 식재된 울릉산마늘의 화분매개곤충을 조사하였다. 2023년 5월 22일부터 6월 2일 까지 꽃이 70% 이상 개화하였을 때 포충망을 활용하여 8일간 곤충을 채집하였고, 각 전시원 별 식생(피도), 기후 (온도·습도·조도)를 조사하였다. 조사 결과 진화속을걷는정원에서 피도 60% 온도 26.4℃, 습도 31.5%, 조도 40953.6lx, 화분매개곤충 20과 450개체, 부추속전문전시원은 피도 90%, 온도 25.6℃, 습도 31.6%, 조도 6387lx, 화분매개곤충 15과 196개체로 나타났다. 온도와 조도가 상대적으로 높은 진화속을걷는정원이 채집된 곤충의 다양성과 방문 빈도가 높았다. 시간대별 곤충의 방문 빈도를 비교해본 결과 온도와 조도는 개체수가 증가할 때 같이 증가하는 경향을 보였으며, 습도는 반대의 경향을 보였다.
        5.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cordycepin (3'-deoxyadenosine) is a nucleoside analog known for its diverse range of biological activities. This study investigated the effect of different types of sawdust on the production of the bioactive compound cordycepin. The results of the study showed that different types of wood sawdust affected the biosynthesis of cordycepin and a significant increase was observed when the conventional SDB medium was replaced with 1% NaOH treated pine sawdust. To optimize cordycepin production from Paecilomyces tenuipes in a medium containing 1% NaOH-pretreated pine sawdust, we employed Response Surface Methodology (RSM) in its Box-Behnken design (BBD) canonical form. The optimal conditions were determined as follows: a particle size of 109.5111-mesh (140 m) for 1% NaOH-pretreated pine sawdust, an input weight of 21.1679 g/L, and an incubation time of 73.8423 hours. According to our model, this combination is expected to yield a maximum cordycepin content of 896.1428 g/mL. Experimental validation of this prediction was performed using the suggested optimal conditions, resulting in an average cordycepin content of 922.6771 g/mL across three replicates, thus confirming the model's accuracy.
        4,000원
        6.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cordyceps militaris (C. militaris) is a unique and valuable medicinal fungus belonging to the Cordyceps species. C. militaris is the only fungus that contains cordycepin which is a biologically active compound. In previous studies, light-emitting diodes (LEDs) are known to be effective in increasing cordycepin content, but metabolic profiling of LED-stimulated C. militaris has not been confirmed. Metabolic profiling is essential to understanding the metabolic regulation of cordycepin. This study studied the physiologically active secondary metabolites of C. militaris according to the presence or absence of stimulation of LEDs through GC-MS analysis. Most of the metabolites were detected in both samples, but there was a clear difference in the detected concentration. In particular, C. militaris had a significant difference in amino acid levels when stimulated with LEDs. Our results suggested that LEDs could stimulate amino acid synthesis in C. militaris mycelium to increase the cordycepin content.
        4,000원
        7.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Roridin E, a constituent of Podostroma cornu-damae, has excellent medicinal properties and exhibits powerful anticancer effects. However, being a poisonous mushroom, P. cornu-damae is difficult to find in its natural environment. Therefore, only a limited amount of roridin E is isolated from P. cornu-damae. We isolated roridin E from mycelial culture medium of P. cornu-damae and examined its effects on five breast cancer cell lines. The purity of the isolated roridin E was 96%. It exhibited anticancer effects on all five breast cancer cell lines, with an IC50 of at least 0.0006 mg/L. To the best of our knowledge, this is the first report on the investigation of effects of roridin E isolated from the mycelium of P. cornu-damae mushrooms on five breast cancer cell lines. However, safety issues should be investigated and addressed in future studies before roridin E is used in clinical settings.
        4,000원
        8.
        2023.05 구독 인증기관·개인회원 무료
        In the event of a radioactive release, it is essential to quickly detect and locate the source of the release, as well as track the movement of the plume to assess the potential impact on public health and safety. Fixed monitoring posts are limited in their ability to provide a complete picture of the radiation distribution, and the information they provide may not be available in real-time. This is why other types of monitoring systems, such as mobile monitoring, aerial monitoring, and personal dosimeters, are also used in emergency situations to complement the information provided by fixed monitoring posts. Also, the monitoring system can be improved by using the Kriging technique, which is one of the interpolation methods, to predict the radiation dose in the relevant districts. This can be achieved by utilizing both the GPS information and the radiation dose measured at a particular point. The Kriging method involves estimating the value between different measurement points by considering the distance between them. The model used GPS and radiation data that were measured around the Hanbit NPP. The data were collected using a radiation measuring detector on a bus that traveled around the NPP area at 2-second intervals for one day. From the collected data, 200 data points were randomly selected for analysis, excluding the data measured at the bus garage out of a total of 16,550 data points. The average dose of the daily measurement data was 117.94 nSv/h, and the average dose of the 200 randomly extracted data was 119.17 nSv/h. The GPS and radiation dose data were utilized to predict the radiation dose around the Yeonggwang area where the Hanbit NPP is located. In the event of an abnormal release of radioactive material, it can be difficult to accurately determine the dose unless a monitoring measurement point is present. This can delay the rapid evacuation of residents during an emergency situation. By utilizing the Kriging model to make predictions, it is anticipated that more accurate dose predictions can be generated, particularly during accident scenarios. This can aid in the development of appropriate resident protection measures.
        12.
        2023.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aimed to verify the whitening effect of Cordyceps militaris, which is distributed in several countries worldwide, including Korea, Japan, and China, and has various medical effects. To screen the efficacy of C. militaris, the inhibitory activity of tyrosinase, which was 66% at a concentration of 1 mg/mL, was measured. Thereafter, the survival rate of melanoma cells was measured, and cell experiments were conducted at a concentration of 90% or more in which C. militaris was not toxic to cells. After measuring the inhibitory effect of TRP-1, TRP-2, tyrosinase protein, and mRNA expression, which are factors influencing melanin synthesis, C. militaris was found to decrease in all factors, with an expression level that was significantly lower compared to quercetin. This confirmed that C. militaris stimulated with LED has excellent whitening activity and can be used as a functional whitening cosmetics material.
        4,000원
        13.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 SAP를 국화(Chrysanthemum morifolium) 분화 생산에 활용하고 SAP의 혼합 비율에 따른 물 사용량과 국화 의 생육을 비교하고자 수행하였다. SAP를 배지의 부피비인 0, 0.05, 0.1, 0.2%로 섞었으며 각각의 처리구는 토양수분함 량 0.50m3・m-3로 일정하게 유지시켰다. 국화의 성장은 초장, 초폭, 뿌리 길이, 개화소요일수를 조사하였다. SAP 0, 0.05, 0.1, 0.2% 처리구에 따르면 식물체의 초장, 초폭, 생체중은 처리구간에 유의한 차이가 없었다. 그러나 지하부 건물중에서 는 0.2% SAP 처리가 대조구보다 유의하게 높았다. 실험 기간 동안 SAP의 혼합 비율에 따라 사용되는 관수량에는 상당한 차이가 있었다. 관수량은 0, 0.05, 0.1, 0.2% SAP 처리에서 각각 43.5, 37.2, 30.1, 29.4L이었다. 결론적으로 동일한 토 양수분조건하에서 SAP의 양에 따른 국화의 생육에는 차이가 없었으나, SAP를 통해 토양의 보수력을 향상시켜 사용되는 물의 양을 크게 줄일 수 있었다.
        4,000원
        14.
        2022.10 구독 인증기관·개인회원 무료
        Republic of Korea (ROK) is operating the Integrated Environmental Radiation Monitoring Network (IERNet) in preparation for a radioactive emergency based on Article 105 of the Nuclear Safety Act (Monitoring of Nationwide Radioactive Environment). 215 radiation monitoring posts are monitoring a wide area, but their location is fixed, so they can’t cover areas where the post is not equipped around the Nuclear Power Plants (NPPs). For this, a mobile radiation monitoring system was developed using a drone or vehicle. However, there are disadvantages: it is performed only at a specific cycle, and an additional workforce is required. In this study, a radiation monitoring system using public transportation was developed to solve the above problems. Considering the range of dose rates from environmental radiation to high radiation doses in accidents, the detector was designed by combining NaI (TI) (in the low-dose area) and GM detector (in the high-dose area). Field test was conducted by installed on a city bus operated by Yeonggwang-gun to confirm the performance of the radiation monitoring system. As a result of the field test, it was confirmed that data is transmitted from the module to the server program in both directions. Based on this study, it will be possible to improve the radiation monitoring capability near nuclear facilities.
        15.
        2022.05 구독 인증기관·개인회원 무료
        Once a radioactive material is released from the nuclear power plant (NPP) by accident, it is necessary to understand the behavior of radioactive plume to protect residents adequately. For this, it is essential to measure the radiation dose rate around NPPs at important locations. Our previous study developed a movable radiation detector that can be installed quickly in an accident to measure gamma dose rate in areas where environmental radiation monitoring system is not installed. The data measured by the detector are transmitted to the server in real-time through LoRA wireless communications. There are two methods to use LoRA communications; one is self-network, and the other is the network provided by the mobile carrier. A signal receiver, called a gateway, should be equipped near the installation location of radiation detectors to use a self-network without using the mobile carrier’s system. In other words, the movable radiation detectors we made can function if there should be any gateway near them. The distance capable of communication between gateway and detector is about 8 km in an open area without significant obstacles. Korea has many significant obstacles, such as mountains around most NPPs. Thus, the gateways could be installed in the proper position before the accident to operate the movable radiation detectors without problems. If the gateway is located at a high position like a mountain top, it could cover a wide area. In this study, the elevation database in the area around the NPPs was collected and analyzed to determine where gateways should be installed. The analysis range is limited in the urgent protective action planning zone. The optimization was also performed to minimize the number of gateways.
        17.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cordyceps militaris, a well-known traditional Chinese medicine, has multiple health-promoting effects. It is used as a herbal remedy and health food in Asian countries. Cultured mycelia are often used as a substitute for natural C. militaris. In the present study, the mycelia and fruiting bodies of artificially cultured C. militaris were analyzed using a metabolomics approach. The protein and crude fat contents of the mycelia were substantially higher than those of the fruiting bodies. The top three abundant amino acids in the mycelia were proline (3.9 g/100 g), aspartic acid (2.9 g/100 g), and glutamic acid (2.7 g/100 g). The carbohydrate content was similar in the fruiting bodies and mycelia. Analysis revealed that both the fruiting bodies and mycelia are rich in phenolic compounds and exhibit antioxidant activity. Further, six metabolites were significantly different between the mycelia and fruiting bodies. The levels of Ca, glucose, Mg, and Se were higher in the mycelia than in the fruiting bodies. In contrast, mannitol and Zn were more abundant in the fruiting bodies. The current study provides a comprehensive metabolic profile of the mycelia and fruiting bodies of artificially cultured C. militaris. Such an exercise is potentially important for understanding the metabolism of C. militaris and facilitating the use of cultured mycelia as a supplement to C. militaris fruiting bodies in traditional Chinese medicine.
        4,000원
        18.
        2021.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The Mn-Zn ferrite powders were prepared by high energy ball milling, then compacted and sintered at various temperatures to assess their sintering behavior and magnetic properties. The initial ferrite powders were spherical in shape with the size of approximately 70 m. After 3 h of ball milling at 300 rpm, aggregated powders ~230 nm in size and composed of ~15 nm nanoparticles were formed. The milled powders had a density of ~70 % when compacted at 490 MPa for 3 min. In the samples subsequently sintered at 1,273 K ~ 1,673 K for 3 h, the MnZnFe2O4 phase was detected. The density of the sintered samples had a tendency to increase with increasing sintering temperature up to 1,473 K, which produced the highest density of 98 %. On the other hand, the sample sintered at 1,373 K had the highest micro-hardness of approximately 610 Hv, which is due to much finer grains.
        4,000원
        19.
        2021.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, we investigated the effect of solid culture medium on the production of cordycepin in Cordyceps militaris. The regression equation was expressed as follows: Y1= 755.3-58.6625X1+4.79432E-14X2-46.6625X3-5.66269E-14X1X2- 0.025X1X3+1.62475E-14X2X3-160.6625X1 2+0.0125X2 2-206.9625X3 2, where, Y represents the value of cordycepin content (μg/g), X1 corresponds to the weight of M. alternatus in solid culture medium (g/bottle), X2 to the water content of the solid culture medium (%), and X3 to the culture period (day). The solid culture medium was optimized using the response surface methodology, and the optimal medium composition was as follows: the weight of M. alternatus in solid culture medium and water content were 16.2% and 100.7% (20.14 mL water/20 g solid culture medium), respectively, with a culture period of 39 days. Under these conditions, the cordycepin content of the fruiting bodies reached 150.0 μg/g (actual value). The supplementation of M. alternatus in solid culture for improved cordycepin content of C. militaris seems to be a promising alternative to wild and solid cultivation.
        4,000원
        20.
        2021.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Roridin E, produced by Podostroma cornu-damae, is a mycotoxin with anticancer activity. To increase the content of roridin E, submerged culture conditions were optimized using response surface methodology. Three factors, namely, medium initial pH, incubation time and agitation speed were optimized using a Box–Behnken design. The optimum submerged culture conditions to increase the content of roridin E included a medium with an initial pH of 4.0, an incubation time of 12.90 days, and an agitation speed of 63.03 rpm. The roridin E content in the submerged culture, under the aforementioned conditions, was 40.26 mg/L. The findings of this study can help lower the current price of roridin E and promote its related research.
        4,000원
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