• Korean Journal of Remote Sensing
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• v.20 no.3
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• pp.163-173
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• 2004

The objective of this study is to develop a method to generate micro-relief digital elevation model (DEM) data of the tidal mudflats using multi-temporal Landsat Thematic Mapper (TM) data. Field spectroscopy measurements showed that reflectance of the exposed mudflat, shallow turbid water, and normal coastal water varied by TM band wavelength. Two sets of DEM data of the inter-tidal mudflat area were generated by interpolating several waterlines extracted from multi-temporal TM data acquired at different sea levels. The waterline appearing in the near-infrared band was different from the one in the middle-infrared band. It was found that the waterline in TM band 4 image was the boundary between the shallow turbid water and normal coastal water and used as a second contour line having 50cm water depth in the study area. DEM data generated by using both TM bands 4 and 5 rendered more detailed topographic relief as compared to the one made by using TM band 5 alone.

• Korean Journal of Pharmacognosy
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• v.52 no.4
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• pp.203-207
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• 2021

LC/MS approach targeting secondary metabolites of bacterial strain resulted in the discovery of boholamide A (1), from the culture of marine actinomycete strain which was isolated from a tidal mudflat in Muan, Republic of Korea. Boholamide A (1), a cyclodepsipeptide with HDMN, APD, glycine, and valine was structurally determined by using 1D/2D NMR spectroscopy, mass spectrometry and UV spectroscopy. Boholamide A (1) showed the inhibitory activity against Bacillus subtilis, with IC₅₀ value of 0.08 mM.

• Journal of Marine Life Science
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• v.2 no.2
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• pp.75-82
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• 2017

Macrobenthos composes the dominant biomass at the mudflat and play an important role in the maintenance of the benthic environments. Organic matter in sedimentary environment affects habitat, feeding behaviors, and survival of benthos. In this study, the relationship between organic matter content in sediment and the distribution of macrobenthos was discussed at two margins (Mokpo and Aphae area) in the mouth of Muan bay. Sediment TOC was higher at Mokpo than at Aphae through the four seasons, and the pollution indicator organism Musculista senhousia was dominant in this area. The macrobenthos distribution was clearly divided into two areas correlated with sediment organic matter content in the mouth of Muan bay.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.421-426
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• 2010

Many bacterial strains inhabit strong saline condition, such as tidal mudflat and salted seafoods, were identified and reported for the proposed protease activities and salt resistance; however antifungal activities against plant fungal pathogen have not well been studied until now. In this study, primary screening was performed for the isolation of promising strains against major plant pathogens like Sclerotinia sclerotiorum, Fusarium oxysporum, Phytophthora capsici, Botrytis cineria, Collectotrichum acutatum and Pythium ultimum. Totally 423 bacterial strain were isolated from laboratory media which was based on different morphological characteristics and all the strains were dual cultured against major fungal pathogens on PDA, finally 40 strains were selected as antifungal bacterial strain and identified by fatty acid phylogenic difference analysis from MIDI shorlock gas chromatography system. As a result, antifungal strains from tidal mudflat were 10 species of 6 genus. Paenibacillus macerans was dominant species; 5 strains among the 17 isolates from tidal mudflat. Antifungal strains from salted seafoods were 7 species of 3 genus and Bacillus atrophaeus was dominant species; 12 strains among the 23 isolates from salted fishes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.7
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• pp.1014-1019
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• 2012

This study was conducted to evaluate the heavy metal contents of mudflat solar salt, salt water, and sea water produced in the nationwide salt pan. In mudflat solar salt, moisture contents were significantly different (p<0.001) between regions, ranging from 7.357% to 14.862%. Arsenic (As) content ranged from 0.007 ppm to 0.497 ppm, cadmium (Cd) from 0.000 ppm to 0.101 ppm, plumbum (Pb) from 0.000 ppm to 0.191 ppm, hydrargyrum (Hg) from 0.006 ppb to 0.180 ppb, and copper (Cu) from 0.039 ppm to 4.794 ppm between regions, which were significantly different (p<0.001). Further, As, Cd, Pb, and Hg contents of sea and salt water were not in excess of their criterion points. Our results suggest that heavy metal contents of mudflat solar salt, salt water, and sea water produced in the nationwide salt pan were at safe levels. However, continuous management of heavy metal contamination, such as PVC met, is still necessary.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05a
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• pp.45-51
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• 2002

• Korean Journal of Microbiology
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• v.23 no.3
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• pp.215-222
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• 1985

Distribution pattern and activity of heterotrophec bacteria were measured in the mudflat of Nakdong river estuary. In March and June, 1985, community sizes of amylolytic, lipolytic and proteolytic bacteria as well as total viable counts were measured. Vertical distribution of bacterial community size increased a few orders of magnitude from Narch to June. Heterotrophic activity was estimated in turnover time with $U-[^{14}C]-glucose$. Turnover time reduced considerably in June compared to that of March. To sxamine correlations for measured bacterial groups, turnover time and environmental factors, correlation coefficient matrix was obtained. These measured characteristics did not consistently correlate well with one another.

• Natural Product Sciences
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• v.22 no.3
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• pp.216-219
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• 2016

The microbial transformation of anthranilic acid (1) by the marine-mudflat-derived fungus Thielavia sp. produced an antibacterial polycyclic quinazoline alkaloid, thielaviazoline (2). The stereostructure of the metabolite was assigned based on detailed spectroscopic data analyses including comparison of the NMR ($^1H$ and $^{13}C$) data with those of reported compound (2). Compound 2 displayed in vitro antimicrobial activity against methicillin-resistant and multidrug-resistant Staphylococcus aureus (MRSA and MDRSA), with minimum inhibitory concentrations (MICs) of 6.25 and $12.5{\mu}g/mL$, respectively. Compound 2 also showed potent radical-scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) with an $IC_{50}$ of $11{\mu}M$, which was more active than the positive control, L-ascorbic acid ($IC_{50}$, $20.0{\mu}M$).

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.110-115
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• 1998

Through the ISODATA method, the micro-landform of Julpo-Bay tidal flat was classified into mudflat, mixedflat, and sandflat using Landsat TM image. Each showed an apparent differences in its topographical characteristics and grain size composition. For example, mudflats are formed with flat faces and tidal channel of dissected gully. Its characteristics of grain size analysis that the grains have less than mean grain size 4 phi. Its sorting is bad (higher than 1 S.D.), and it showed strongly positive skewness. But sandflat is topographically flat without tidal channel. It has developed with ripple marks. According to the grain size analysis of deposits, the soil is coarse size with 90% of sand and its sorting is well(lower than 1 S.D.) Also, it showed strongly negative skewness. Mixed flat is in between mudflat and sandflat in its characteristics.

• Korean Journal of Microbiology
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• v.23 no.2
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• pp.157-165
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• 1985

Bacterial identification was performed with morphological, physiological and biochemical tests to the isolates from the mudflat of 30cm depth sampled in Nakdong river estuary in March and June, 1985. Flavobacterium and Cnterobacteriaceae were regarded as dominants. Pseudomonas, Bacillus, Micrococcus, Vibrio, Aerococcus, Aerononas, Acinetobacter and Staphylococcus were founded in various depth. Vertical composition of bacterial genera in March was more diversiform than that of June. Character analysis was carried out with the calculation of similarity index (S). At a level of 85% similarity, the isolates were clustered into 5 groups and ungrouped 2 strains. Classifying groups of bacterial strains with determination schemes and groups from similarity index were in good agreement.