• Microbiology and Biotechnology Letters
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• v.49 no.1
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• pp.111-119
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• 2021

A bacterial strain isolated from a Malva verticillata leaf was identified as Bacillus velezensis MV2 based on the 16S rRNA sequencing results. Complete genome sequencing revealed that B. velezensis MV2 possessed a single 4,191,702-bp contig with 45.57% GC content. Generally, Bacillus spp. are known to produce diverse antimicrobial compounds including bacteriocins, polyketides, and non-ribosomal peptides. Antimicrobial compounds in the B. velezensis MV2 were extracted from culture supernatants using hydrophobic interaction chromatography. The crude extracts showed antimicrobial activity against both gram-positive bacteria and gram-negative bacteria; however, they were more effective against gram-positive bacteria. The extracts also showed antifungal activity against phytopathogenic fungi such as Fusarium fujikuroi and F. graminearum. In time-kill assays, these antimicrobial compounds showed bactericidal activity against Bacillus cereus, used as indicator strain. To predict the type of antimicrobial compounds produced by this strain, we used the antiSMASH algorithm. Forty-seven secondary metabolites were predicted to be synthesized in MV2, and among them, fourteen were identified with a similarity of 80% or more with those previously identified. Based on the antimicrobial properties, the antimicrobial compounds may be nonribosomal peptides or polyketides. These compounds possess the potential to be used as biopesticides in the food and agricultural industry as an alternative to antibiotics.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.4
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• pp.500-509
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• 2021

This study investigated the characteristics of a macrobenthos community and sediment environment and assessed the health of tidal flats along the west coast of Korea. A survey was conducted from Ganghwa-do to Mokpo, Jeollanam-do in April (spring) and August (summer) 2017, and April (spring) 2018. The sediment grain sizes in the Chungcheongnam-do region were coarser, and the sediment in the Gyeonggi-do·Incheon, Jeollanam-do, and Jeollabuk-do regions were finer. A total of 140 macrobenthic species were collected from this study and using a cluster similarity analysis of the macrobenthos community, they were divided into four groups. Group2 was associated with Manila clam farm stations, and Ruditapes phillipinarum, Nephtys polybranchia and Lumbrineris nipponica were dominant. Group4 included some sites with finer sediment composed relatively, and Eteone longa and Nemertea unid. appeared at a high frequency. From the health assessment of the western tidal flat, the ISEP and BHI indices had a "High status," and the AMBI index had a "Good status." In conclusion, the tidal flats along the west coast of Korea have good ecological health. However, pollution indicator species such as Theora lata and Capitella capitata have appeared in some areas. Therefore, periodic administration and interventions are necessary to prevent deterioration of the tidal flat environment.

• Journal of Intelligence and Information Systems
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• v.27 no.1
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• pp.47-64
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• 2021

The global spread of COVID-19 around the world has not only affected many parts of our daily life but also has a huge impact on many areas, including the economy and society. As the number of confirmed cases and deaths increases, medical staff and the public are said to be experiencing psychological problems such as anxiety, depression, and stress. The collective tragedy that accompanies the epidemic raises fear and anxiety, which is known to cause enormous disruptions to the behavior and psychological well-being of many. Long-term negative emotions can reduce people's immunity and destroy their physical balance, so it is essential to understand the psychological state of COVID-19. This study suggests a method of monitoring medial news reflecting current days which requires striving not only for physical but also for psychological quarantine in the prolonged COVID-19 situation. Moreover, it is presented how an easier method of analyzing social media networks applies to those cases. The aim of this study is to assist health policymakers in fast and complex decision-making processes. News plays a major role in setting the policy agenda. Among various major media, news headlines are considered important in the field of communication science as a summary of the core content that the media wants to convey to the audiences who read it. News data used in this study was easily collected using "Bigkinds" that is created by integrating big data technology. With the collected news data, keywords were classified through text mining, and the relationship between words was visualized through semantic network analysis between keywords. Using the KrKwic program, a Korean semantic network analysis tool, text mining was performed and the frequency of words was calculated to easily identify keywords. The frequency of words appearing in keywords of articles related to COVID-19 emotions was checked and visualized in word cloud 'China', 'anxiety', 'situation', 'mind', 'social', and 'health' appeared high in relation to the emotions of COVID-19. In addition, UCINET, a specialized social network analysis program, was used to analyze connection centrality and cluster analysis, and a method of visualizing a graph using Net Draw was performed. As a result of analyzing the connection centrality between each data, it was found that the most central keywords in the keyword-centric network were 'psychology', 'COVID-19', 'blue', and 'anxiety'. The network of frequency of co-occurrence among the keywords appearing in the headlines of the news was visualized as a graph. The thickness of the line on the graph is proportional to the frequency of co-occurrence, and if the frequency of two words appearing at the same time is high, it is indicated by a thick line. It can be seen that the 'COVID-blue' pair is displayed in the boldest, and the 'COVID-emotion' and 'COVID-anxiety' pairs are displayed with a relatively thick line. 'Blue' related to COVID-19 is a word that means depression, and it was confirmed that COVID-19 and depression are keywords that should be of interest now. The research methodology used in this study has the convenience of being able to quickly measure social phenomena and changes while reducing costs. In this study, by analyzing news headlines, we were able to identify people's feelings and perceptions on issues related to COVID-19 depression, and identify the main agendas to be analyzed by deriving important keywords. By presenting and visualizing the subject and important keywords related to the COVID-19 emotion at a time, medical policy managers will be able to be provided a variety of perspectives when identifying and researching the regarding phenomenon. It is expected that it can help to use it as basic data for support, treatment and service development for psychological quarantine issues related to COVID-19.

• Journal of Nutrition and Health
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• v.54 no.1
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• pp.23-38
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• 2021

Purpose: This study was undertaken to evaluate the health, nutritional status and metabolic syndrome risk according to the dietary pattern of adult single-person households, using information obtained from the Korea National Health and Nutrition Examination Survey (KNHANES). Methods: Data were collected from the 2013-2016 KNHANES, of adults aged 19-64 years, belonging to single-person households. Based on cluster analysis, the dietary patterns of subjects were classified into three groups. The dietary behavior factors, health-related factors, nutritional status, and prevalence of metabolic syndrome obtained from KNHANES questionnaires were compared according to the individual dietary pattern. The nutrient intake data of the subjects were calculated using the semi-food frequency questionnaire. Moreover, blood and physical measurement data of the subjects were analyzed to obtain the prevalence of metabolic syndromes. Results: The major dietary intakes of subjects were classified as 'Rice and kimchi', 'Mixed', and 'Milk·dairy products and fruits' patterns. Characteristics of subjects based on their dietary pattern, gender, age, and education level were significantly different. The 'Milk and fruits' pattern showed low frequency of skipping breakfast and eating out, and had higher intake of dietary supplements. Frequency of alcohol intake and smoking rates were highest in the 'Mixed' pattern. Maximum nutrient intake of fat, vitamin A, riboflavin, vitamin C, niacin, calcium, phosphorus, and potassium was obtained in the 'Milk·dairy products and fruits' pattern. According to dietary patterns adjusted for age and gender, the risk of metabolic syndrome was 0.380 times lower in the 'Milk·dairy products and fruit' pattern than in the 'Rice and kimchi' pattern. However, when adjusted for other confounding factors, no significant difference was obtained between dietary patterns for metabolic syndrome risk. Conclusion: These results indicate that the health and nutritional status of a single-person household is possibly affected by the dietary intake of subjects.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.4
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• pp.64-73
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• 2021

The purpose of this study is to present a method to assess the landscape aesthetic value of Bukhansan National Park using geotagged images that have been shared on social media sites. The method presented in this study consisted mainly of collecting geotagged image data, identifying landscape images, and analyzing the cumulative visibility by applying a target probability index. Ramblr is an application that supports outdoor activities with many users in Korea, from which a total of 110,954 geotagged images for Bukhansan National Park were collected and used to assess the landscape aesthetics. The collected geotagged images were interpreted using the Google Vision API, and were subsequently were divided into 11 landscape image types and 9 non-landscape image types through cluster analysis. As a result of analyzing the landscape types of Bukhansan National Park based on the extracted landscape images, landscape types related to topographical characteristics, such as peaks and mountain ranges, accounted for the largest portion, and forest landscapes, foliage landscapes, and waterscapes were also commonly found as major landscape types. In the derived landscape aesthetic value map, the higher the elevation and slope, the higher the overall landscape aesthetic value, according to the proportion and characteristics of these major landscape types. However, high landscape aesthetic values were also confirmed in some areas of lowlands with gentle slopes. In addition, the Bukhansan area was evaluated to have higher landscape aesthetics than the Dobongsan area. Despite the high elevation and slope, the Dobongsan area had a relatively low landscape aesthetic value. This shows that the aesthetic value of the landscape is strongly related not only to the physical environment but also to the recreational activities of visitors who are viewing the scenery. In this way, the landscape aesthetics assessment using the cumulative visibility of geotagged images is expected to be useful for planning and managing the landscape of Bukhansan National Park in the future, through allowing the geographical understanding of the landscape values based on people's perceptions and the identification of the regional deviations.

• Journal of Life Science
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• v.31 no.6
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• pp.543-549
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• 2021

Approximately 10% of all angiosperms belong to the Asteraceae family. Plant species belonging to this family have traditionally been used as medicinal plants in the Korean Peninsula. We investigated the antioxidant activity of seed extracts from 14 species belonging to the Asteraceae family. Seeds with ≥ 90% percentage of filled seed and ≥ 50% final germination were used. The total phenolic content was the highest in Dendranthema zawadskii var. tenuisectum (13.5 mg of gallic acid equivalents (GAEs)/g seeds), followed by Dendranthema zawadskii var. latilobum (11.8 mg of GAEs/g seeds), and Callistephus chinensis (11.0 mg of GAEs/g seeds). The total flavonoid content was highest in C. chinensis (9.8 mg of quercetin equivalents (QEs)/g seeds), followed by D. zawadskii var. tenuisectum (7.2 mg of QEs/g seeds) and Taraxacum officinale (6.3 mg of QEs/g seeds). Our results showed that 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging activity was highest in D. zawadskii var. tenuisectum (57.4 ㎍/ml), followed by T. officinale (59.1 ㎍/ml) and D. zawadskii var. latilobum (65.0 ㎍/ml), with a half maximal inhibitory concentration (IC₅₀) of DPPH scavenging activity. Furthermore, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity was highest in C. chinensis (26.2 ㎍/ml), followed by D. zawadskii var. tenuisectum (38.4 ㎍/ml), T. officinale (40.2 ㎍/ml), with a half maximal inhibitory concentration (IC₅₀) of ABTS scavenging activity. Based on a cluster analysis according to the antioxidant activity, the 14 species were classified into five groups, with group 4 having the highest antioxidant activity and group 0 having the lowest antioxidant activity. D. zawadskii var. latilobum, D. zawadskii var. tenuisectum, T. officinale, and C. chinensis belonging to groups 3 and 4, exhibited high phenolic content and antioxidant activity and can be considered potent plant-derived natural antioxidants.

• Journal of Life Science
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• v.31 no.6
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• pp.559-567
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• 2021

This study compared the nutritional characteristics and antioxidant effects of sea mustards sourced from five different areas (Barammaegi, Gultongmeori, Chanmulgae, Johongtaek, and Goraedeung) in Taejongdae, Youngdo, Busan. The contents of total flavonoids and phenols and fatty acid composition were measured. To evaluate their antioxidant effects, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays were used. Acetone/methylene chloride (A+M) extracts from all the sea mustards contained higher amounts of total flavonoids and phenols than methanol (MeOH) extracts. Among the sea mustards obtained from the different areas, the total flavonoid and total phenolic content of the A+M extract of the sea mustard from Gultongmeori was 1.44±0.04 mg/g and 1.72±0.06 mg/g, respectively. In terms of the fatty acid composition, the Gultongmeori sea mustard had higher percentages of total n-6, total n-3, eicosapentaenoic acid (EPA, 20:5n-3), and docosahexaenoic acid (DHA, 22:6n-3) than the sea mustards from the other areas. The A+M extract of the sea mustard from Gultongmeori was more effective in terms of scavenging free radicals as compared with that of the other sea mustards, as assessed by the DPPH and ABTS assays (p<0.05). In a 120-minute reactive oxygen species (ROS) production assay, all the extracts tested decreased cellular ROS production induced by H₂O₂ compared to that produced by exposure to an extract-free control (p<0.05). The extracts from Barammaegi and Gultongmeori had a greater inhibitory effect on cellular ROS production. These results indicated that the antioxidant effects of sea mustards might be associated with a higher amount of flavonoids and phenols. This study suggests that food-processed products from sea mustard can be developed as functional foods for promoting health in the local population.

• Journal of Food Hygiene and Safety
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• v.36 no.6
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• pp.481-487
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• 2021

The purpose of this study was to provide safety management information by analyzing the survival and growth-related properties of foodborne pathogens from Romaine lettuce. After cultivating E. coli O157:H7 for 72 h on Romain lettuce via spray inoculation, the bacteria population increased by 2.0 log CFU/g from the initial population, confirming the possibility of survival and multiplication of the pathogen thereon. The study also revealed that there is no significant difference in the cultivation of E.coli O157:H7 after 72 h from inoculation on damaged and undamaged lettuce leaves. As a result of investigating distribution of E.coli O157:H7 on damaged lettuce leaves, it was found that the bacteria is unlikely to adhere on the smooth surface of undamaged leaves and, thus, results in a low population density, whereas the bacteria cluster on the rough surface of damaged leaves and easily enter through the damaged tissues. Furthermore, after 24 h of cultivation of the pathogenic microbe in the extract with concentrations of 10-100%, utilization of the lettuce extract by the pathogen was found to be 8.9 log CFU/mL E. coli O157:H7, 8.6 log CFU/mL L. monocytogenes, and 8.8 log CFU/mL P. carotovorum. The increase in the population of both the pathogenic microbe and foodborne pathogen reached over 4 log CFU/mL, implying the microbe can utilize the lettuce extract as a source of nutrition. Compared to the initial inoculation concentration in 0.1% lettuce extract, the final concentration has increased up to 2.7 log CFU/mL E. coli O157:H7, 1.3 log CFU/mL L. monocytogenes, and 2.9 log CFU/mL P. carotovorum. Accordingly, the study confirms that the minimal growth concentration of the pathogenic microbe is lower than 0.1% and that the pathogen possibly survive and multiply inside the lettuce leaves given the lettuce extract with concentration of 0.1% is consistently supplied through the damaged tissues.

• Korean Journal of Plant Resources
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• v.35 no.1
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• pp.1-9
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• 2022

Perilla is an annual plant in the family Lamiaceae and are widely cultivated in Asian countries. Perilla leaves are important sources of bioactive compounds and are reported to exhibit anti-inflammatory, antibacterial, anti-cancer and antioxidant effects, drawing attention as functional food materials. We examined caffeic acid, rosmarinic acid, total phenol content, and antioxidant activity in the leaves of 18 perilla accessions obtained from the gene bank of the National Agrobiodiversity Center, Jeonju, Korea. The caffeic acid content ranged between 9.86-27.52 mg/g with an average content of 17.75 mg/g while the level of. rosmarinic acid was in the range between 49.14 and 90.30 mg/g with an average content of 61.88 mg/g. The total polyphenol content ranged between 138.39 ㎍ GAE/mg dried extract (DE) and 378.19 ㎍ GAE/mg DE with an average content of 225.93 ㎍ GAE/mg DE. Cluster analysis based on the content of caffeic acid, rosmarinic acid. and antioxidant activity showed that the accessions collections were grouped in two distinct classes. The first group contained six genetic resources with high content of rosmarinic acid, and antioxidant activities respectively. The second group contained 12 genetic resources with high content of caffeic acid. These results could help develop new varieties of nutrient dense perilla resources.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.27 no.2
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• pp.87-102
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• 2022

To clarify the spatial distribution pattern of macrozoobenthos in Korean coastal waters in the summer season and investigate the relationship between community structure and benthic environmental factors, field surveys on community structure and benthic environmental factors were conducted at 117 stations in August 2017. A total of 613 macrobenthic species were identified, with the mean density of 1,228 ind./m² and the mean biomass (wet weight) of 110.9 g WW/m². Rich biodiversity was found at stations near Wando and along the coast of the East Sea, and there is a trend that stations with greater biodiversity also showed higher mean density as well. The dominant species in all the coastal areas in Korea was Heteromastus filiformis, which were found at most of the stations during the survey. The relatively deep areas in the East Sea were dominated by Magelona johnsoni and Maldane cristata, which were the third and ninth dominant species in the study areas, respectively. Pseudopolydora kempi and Rhynchospio sp. were observed only at the station located in the Nakdong River estuary. From the cluster analysis the stations could be clustered into three station groups with more similar faunal composition. Group A was located in the eastern coast, characterized with deep water depth and low levels of sand contents, while Group B was located in the southern coast, characterized by shallow depth of water and high content of mud and organic matter. Lastly, Group C was in the western coast, demonstrating low levels of mud content and organic matters. The biodiversity of macrobenthic species in the study area showed high positive correlation coefficients with benthic environmental factors such as sorting, clay, silt, and contents of organic matter in sediments, but negatively correlated with the sand contents. Major dominant species, Theora lata and Eriopisella sechellensis, both showed negative correlation coefficients with the sand contents, but a relatively high positive correlation with the levels of organic contents.It can be concluded that the spatial distribution patterns of macrobenthic organisms in Korean coastal waters are affected by depth, sediment type, and contents of organic matters.