• Journal of Applied Biological Chemistry
• /
• v.65 no.3
• /
• pp.203-213
• /
• 2022

Abeliophyllum distichum (A. distichum, Korean endemic plant) is one genus and one species in the Oleaceae family. According to the color variation of petals and calyx, A. distichum is classified as A. distichum (white flower), A. distichum for. lilacinum (pink flowers), A. distichum for. eburneum (ivory flowers), and Okhwang 1 (golden flowers). In previous studies, bioactivities (antioxidant, anti-inflammatory, and anti-cancer) of A. distichum have been reported. We conducted a comparison of the differences in bioactive compounds and the anti-inflammatory effects on macrophages among four flowers of A. distichum (FAD). The identification and quantification of glycosides were analyzed by HPLC/PDA and LCMS. These results were shown FAD has rutin, hirsutrin, and acteoside. Antioxidant activity of FAD significantly decreased reactive oxygen species. In addition, FAD reduced the expression of pro-inflammatory mediators (nitric oxide, iNOS, and COX-2) in lipopolysaccharide-induced RAW 264.7 cells. For further study, we investigated the regulation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. In conclusion, FAD may exert anti-inflammatory effects by suppressing inflammatory mediators via regulations of NF-κB and MAPK signaling pathways. Therefore, these findings suggest that FAD is a potential resource as a preventative or therapeutic agent for inflammation.

• Journal of Mushroom
• /
• v.20 no.2
• /
• pp.69-77
• /
• 2022

Eco-friendly materials, such as alternative vegan materials using various fungal resources, are being actively researched to reduce environmental pollution and facilitate a healthy lifestyle. The fungal mycelium-based mushroom mycelium mat is one such emerging material. In this study, the commonly used mushroom mycelium culture method was modified to reduce the time required to produce the mycelium mat, lower the possibility of contamination, and improve the properties and quality of the mat. Shortening the period required for the previously used primary bag culture and secondary mat production culture. A culture method in which the bag culture was omitted was attempted using a mycelium mutated by gamma irradiation to the mycelium of Trametes orientalis. In addition, various nutrients were added to the fungal solution to observe the change in physical properties of the fungal mat. High-quality mycelium mats were produced in the experimental group containing 1.5% CaCO₃ in sawdust medium, and the period was also reduced by more than 10 days compared to the existing production method. In the future, for mass producing mycelium mats, additional selection of medium components and optimization of culture conditions are essential.

• Korean Journal of Ecology and Environment
• /
• v.55 no.4
• /
• pp.360-367
• /
• 2022

Research on food sources through DNA metabarcoding is being used for various organisms based on high resolution and reproducibility. In the study, we investigated the difference in food sources between pre and post-starving in the three bivalve species (Anemina acaeformis, Anodonta woodiana, and Unio douglasiae) through DNA metabarcoding using 18S rRNA V9 primer. The food source of pre-starving appeared in 87 genera, 71 families, 51 orders, 35 classes, and 22 phyla. The primary food sources were the zoo and phytoplankton, including Chlamydomonadales, Euglenales, Ploima, Sphaeropleales, and Stephanodiscales. However, all zoo and phytoplankton were not observed after starving except Schizopyrenida and Rotifera. In Levin's niche breadth analysis, the Bi index of A. woodiana is 0.3, which was higher than A. acaeformis(0.14) and U. douglasiae (0.21), indicating that they feed on various food sources. The niche overlap of A. acaeformis was measured as 0.78 in A. woodiana, 0.7 in U. douglasiae showing a relative high value compared to other bivalves. The trophic level of A. acaeformis, A. woodiana, and U. douglasiae based on the food source information were investigated as 2.0, 2.0, and 2.5, respectively. The results of the previous study on the trophic level using stable isotopes showed 1.8 to 2.4 values were similar to the results of this study. These results suggest that DNA metabarcoding can be an effective analyzing tool for the gut content in the bivalves.

• Journal of Mushroom
• /
• v.21 no.3
• /
• pp.88-92
• /
• 2023

In this review, we examine the latest technological developments in the utilization of truffles, a gourmet ingredient reputed to be one of the "world's three greatest delicacies," considering changing global consumption trends. Global demand for truffles is expected to increase steadily, with an average annual growth rate of 8.9% from 2023 to 2030. As truffles are expensive, the demand for truffles is expected to be concentrated in developed countries such as the United States, European countries, and Japan. In Korea, truffles are utilized in various industries, including food, functional foods, and cosmetics. Korean consumer demand for truffles has consistently remained high since 2019, and truffle products have been performing well in the market. Consequently, there exists substantial potential demand for newly developed truffle-related products and technologies. This review aims to provide objective research information through the systematic analysis of patent applications in Korea and internationally, focusing on technologies involving truffles, and can aid in setting directions for research and development.

• Korean Journal of Ecology and Environment
• /
• v.56 no.1
• /
• pp.70-82
• /
• 2023

Recently, Korean government has introduced Multi Metric Indices (MMI) using various biocommunity information for aquatic ecosystem monitoring and ecosystem health assessment at the national level. MMI is a key tool in national ecosystem health assessment programs. The MMI consists of indices that respond to different target environmental factors, including environmental disturbance (e.g. nutrients, hydrological and hydraulic situation of site etc.). We used zooplankton community information collected from Korean lakes to estimate the availability of candidate zooplankton MMI indices that can be used to assess lake ecosystem health. First, we modified the candidate indices proposed by the U.S. EPA to suit Korean conditions. The modified indices were subjected to individual index suitability analysis, correlation analysis with environmental variables, and redundancy analysis among indices, and 19 indices were finally selected. Taxonomic diversity was suggested to be an important indicator for all three taxonomic groups (cladoceran, copepod, rotifer), on the other hand, the indices using biomass for large cladocerans and copepods, while the indices using abundance were suggested for small cladocerans and rotifers.

• Korean Journal of Environmental Agriculture
• /
• v.41 no.1
• /
• pp.41-49
• /
• 2022

BACKGROUND: The main source of ammonia in soils, South Korea is agricultural emissions (e.g., fertilizer application and livestock manure), with the recent emission inventories reporting them to be approximately 80% of the total emissions. Ammonia as a pollutant is originated largely from agricultural activity and is an important contributor to air quality issues in South Korea. The importance of ammonia in agricultural land is also emerging. In this study, the characteristics of ammonia emission from Chinese cabbage cultivation fields with application rates of urea sere were evaluated. METHODS AND RESULTS: The ammonia emission characteristics were investigated at the different urea application rates (0, 160, 320, and 640 kg ha-1) and the ammonia emission factor in the Chinese cabbage cultivation field was calculated. As application rate of urea application increased, ammonia emissions increased proportionally. In 2020 and 2021, cumulative ammonia emissions with urea 320 kg ha^-1 treatment were 39.3 and 35.2 kg ha^-1, respectively for 2020 and 2021. When urea fertilizer was applied, the ammonia emission factors were 0.1217 and 0.1358 NH₄⁺-N kg N kg^-1 in 2020 and 2021, respectively. CONCLUSION(S): Ammonia emissions increased as application rate of urea increased, and the average ammonia emission factor of the Chinese cabbage cultivation field for two years was 0.129 NH₄⁺-N kg N kg^-1.

• Korean Journal of Ecology and Environment
• /
• v.56 no.2
• /
• pp.140-150
• /
• 2023

The Hangang River^* is necessary to manage the water environment of severe pollution due to the high density of residential areas, parks, and agriculture and the large population concentrated there. Benthic macroinvertebrates, such as chironomids larvae, are bioindicator species that reflect environmental changes and are crucial for water quality monitoring. In this study, we investigated morphological characteristics and molecular analysis of the chironomids larvae inhabiting the Hangang River area for water environment surveys. For this research, 20 rivers, lakes, and urban area in the Hangang River basin were selected. Chironomids larvae were collected from July to September 2022, and their appearance and characteristics were identified through morphological identification. In addition, phylogenetic analysis was performed based on the mtCOI gene sequences of the collected chironomids larvae, and identification at the genus level was confirmed. As a result, 32 species and 18 genera of 3 subfamilies of Chironomidae larvae were identified, and Stictochironomus sp. dominated most sites(6 sites). The morphological characteristics of the identified chironomids larvae, such as the mentum, ventromental plate, and antenna, were organized into table and pictorial keys, and a Bayesian inference molecular phylogeny was presented. These results provide basic morphological information for genus-level identification and can be used as fundamental information for water quality management.

• Korean Journal of Environmental Agriculture
• /
• v.42 no.2
• /
• pp.159-167
• /
• 2023

Food waste (FW) emissions in South Korea amounted to 4.77 million tons in 2021, and continue to increase. Various technologies have been developed to treat FW, with recent research focusing on biochar production through pyrolysis to reduce FW. However, the agricultural application of food waste-biochar (FWBC) is limited by the salt accumulated during pyrolysis. This study investigated salt removal from and the kinetic characteristics of FWBC, and subsequently evaluated its agricultural applications. FW was pyrolyzed at 350℃ for 4 h, and subsequently washed for 0.1, 0.25, 0.5, 0.75, 1, 5, 15, and 30 min to remove salt. FWBC had a salt concentration of 5.75%, which was effectively removed through washing. The salt concentration decreased rapidly at the beginning (1 min) and then slowly decreased, unlike in FW, in which the salt decreased continuously and slowly. The salt removal speed constant (K) was 1.5586 (Stage 1, FWBC) > 0.0445 (Stage 2, FWBC) > 0.0026 (FW). In a lettuce cultivation experiment, higher biomass was achieved using washed FWBC than when using unwashed FWBC and FW, and soil properties were improved. Overall, these findings suggest that although FW reduction using pyrolysis causes a salt accumulation problem, the salt can be effectively removed through washing. The use of washed FWBC can enhance plant growth and soil properties.

• Korean Journal of Remote Sensing
• /
• v.39 no.6_2
• /
• pp.1529-1539
• /
• 2023

The data from Geostationary Ocean Color Imager-II (GOCI-II), which observes the color of the sea to monitor marine environments, undergoes various correction processes in the ground station system, producing data from Raw to Level-2 (L2). Quality issues arising at each processing stage accumulate step by step, leading to an amplification of errors in the satellite data. To address this, improvements were made to the GOCI-II ground station system to measure potential optical quality and geolocation accuracy errors in the Level-1A/B (L1A/B) data. A newly established Radiometric and Geometric Performance Assessment Module (RGPAM) now measures five optical quality factors and four geolocation accuracy factors in near real-time. Testing with GOCI-II data has shown that RGPAM's functions, including data processing, display and download of measurement results, work well. The performance metrics obtained through RGPAM are expected to serve as foundational data for real-time radiometric correction model enhancements, assessment of L1 data quality consistency, and the development of reprocessing strategies to address identified issues related to the GOCI-II detector's sensitivity degradation.

• Korean Journal of Remote Sensing
• /
• v.39 no.6_2
• /
• pp.1541-1551
• /
• 2023

Radiometric calibration is a fundamental step in ocean color remote sensing since the step to derive solar radiance spectrum in visible to near-infrared wavelengths from the sensor-observed electromagnetic signals. Generally, satellite sensor suffers from degradation over the mission period, which results in biases/uncertainties in radiometric calibration and the final ocean products such as water-leaving radiance, chlorophyll-a concentration, and colored dissolved organic matter. Therefore, the importance of radiometric calibration for the continuity of ocean color satellites has been emphasized internationally. This study introduces an approach to improve the radiometric calibration algorithm for the visible bands of the Geostationary Ocean Color Imager-II (GOCI-II) satellite with a focus on stability. Solar Diffuser (SD) measurements were employed as an on-orbit radiometric calibration reference, to obtain the continuous monitoring of absolute gain values. Time series analysis of GOCI-II absolute gains revealed seasonal variations depending on the azimuth angle, as well as long-term trends by possible sensor degradation effects. To resolve the complexities in gain variability, an azimuth angle correction model was developed to eliminate seasonal periodicity, and a sensor degradation correction model was applied to estimate nonlinear trends in the absolute gain parameters. The results demonstrate the effects of the azimuth angle correction and sensor degradation correction model on the spectrum of Top of Atmosphere (TOA) radiance, confirming the capability for improving the long-term stability of GOCI-II data.