• Journal of Soil and Groundwater Environment
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• v.17 no.3
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• pp.49-58
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• 2012

Batch experiments using indigenous and commercialized adventive microorganisms were performed to investigate the feasibility of the biodegradation process for the diesel contaminated soil, which was taken in US Military Camp 'Hialeah', Korea. TPH concentration of the soil was determined as 3,819 mg/kg. Four indigenous microorganisms having high TPH degradation activity were isolated from the soil and by 16S rRNA gene sequence analysis, they were identified as Arthrobacter sp., Burkholderia sp., Cupriavidus sp. and Bacillus sp.. Two kinds of commercialized solutions cultured with adventive microorganisms were also used for the experiments. Various biodegradation conditions such as the amount of microorganism, water content and the temperature were applied to decide the optimal bioavailability condition in the experiments. In the case of soils without additional microorganisms (on the natural attenuation condition), 35% of initial TPH was removed from the soil by inhabitant microorganisms in soil for 30 days. When the commercialized microorganism cultured solutions were added into the soil, their average TPH removal efficiencies were 64%, and 54%, respectively, which were higher than that without additional microorganisms. When indigenous microorganisms isolated from the contaminated soil were added into the soil, TPH removal efficiency increased up to 95% (for Bacillus sp.). According to the calculation of the average biodegradation rates for Bacillus sp., the remediation goal (87% of the removal efficiency: 500 mg/kg) for the soil would reach within 24 days. Results suggested that TPH removal efficiency of biodegradation by injecting indigenous microorganisms is better than those by injecting commercialized adventive microorganisms and only by using the natural attenuation.

• Mycobiology
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• v.48 no.5
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• pp.392-398
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• 2020

This study was conducted to understand the dynamics of microbial communities of soil microorganisms, and their distribution and abundance in the indigenous microorganisms (IMOs) manipulated from humus collected from the forest near the crop field. The soil microorganisms originated from humus and artificially cultured microbial-based soil amendments were characterized by molecular and biochemical analyses. The bacterial population (2 × 10⁶~13 × 10⁶ CFU/g sample) was approximately 100-fold abundant than the fungal population (2 × 10⁴~8 × 10⁴ CFU/g sample). The 16S rDNA and ITS sequence analyses showed that the bacterial and fungal communities in humus and IMOs were mainly composed of Bacillus and Pseudomonas, and Trichoderma and Aspergillus species, respectively. Some of the bacterial isolates from the humus and IMOs showed strong inhibitory activity against soil-borne pathogenic fungi Fusarium oxysporum and Sclerotinia sclerotiorum. These bacteria also showed the siderophore production activity as well as phosphate solubilizing activity, which are requisite traits for biological control of plant pathogenic fungi. These results suggest that humus and IMOs could be a useful resource for sustainable agriculture.

• The Korean Journal of Mycology
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• v.49 no.4
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• pp.433-440
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• 2021

The fungal genus Trametes is globally distributed and comprises various wood-decay species, including the well-known medicinal mushroom Trametes versicolor, a popular remedy in traditional Asian medicine. Trametes species produce antioxidants, which have a wide range of health benefits. The pressent study evaluated seven indigenous Trametes species from Korea, which were cultivated in three different media (dextrose-yeast extract, DY; malt extract-yeast extract, MY; malt extract broth, MEB) and tested for antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assays. We found that the medium consumption rate did not significantly differ between the media and among the strains (72-76%). However, the T. versicolor strains had a relatively low consumption rate (14-65%). The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) tests demonstrated that culture filtrates of T. cf. junipericola, T. orientalis, T. suaveolens, and T. versicolor possessed antioxidant activity against damage from free radicals. In particular, T. cf. junipericola (DY) and T. versicolor (MY) had >80% activity in the DPPH and ABTS assays, compared with that of the positive control (ascorbic acid). Thus, our study identified promising candidates with substantial antioxidant activity among the indigenous strains of Trametes spp. from Korea.

• The Korean Journal of Mycology
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• v.49 no.2
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• pp.211-242
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• 2021

Indigenous yeasts in Korea have been actively studied since 1910 in light of various fields, including environment, food fermentation, brewing, and medicine. However, a complete list of indigenous yeast species has not been addressed or reported. In this study, a comprehensive analysis of the literature including yeast isolation from Korean materials and the strains preserved at culture collections was performed. The results of this study indicate the following: i) there are 128 genera and 681 species (including 26 variants) of yeast reported in Korea, ii) the reported species were trimmed into 142 genera and 500 species (including 9 variants), iii) among which only 166 species were registered in the National Species List of Korea (2020). Therefore, follow-up studies are required to register more indigenous yeast species in the National Species List of Korea.

• Journal of Applied Biological Chemistry
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• v.42 no.1
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• pp.7-11
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• 1999

An extracellular chitinase of the selected strong antifungal microorganism, Serratia sp. 3095, was purified by salting out, affinity adsorption, Sepadex G-100 gel fitration, Sepadex G-75 gel fitration and DEAE Sepadex A-50 chromatography. The molecular weight of the purified chitinase was estimated to be 62,000 dalton by SDS-PAGE. Optimal pH and temperature of the chitinase were pH 7.5 and 45, respectively. The enzyme retained more than 80% of the activity between pH 5.5 and pH 10.5, and below $50^{\circ}C$ but was unstable above $60^{\circ}C$, below pH 5.0. The activity of the chitinase was inhibited about 60% by $Sn^{2+}$, 40% by $Hg^{2+}$ and $Ag^+$, 70% by AHA, 40% by iodoacetate, 35% by thiourea and p-CMB, but stabilized by SDS. $K_m$ value of the purified chitinase was 3.68 mg/ml for colloidal chitin. The chitinase from Serratia sp. 3095 showed antifungal activity to Fusariurm solani.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.162-166
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• 2004

This study investigated tile effect of ozonation on indigenous microorganisms distributed in different size fractions of soil aggregates. Soil was ozonated from 0 to 300 minutes. The treated soils were fractionated into 3 groups (small, <53 $\mu$m; medium, 53-500 $\mu$m; and large, 2000-500 $\mu$m) and total heterotrophic bacteria in the soils were enumerated. Cell number decreased rapidly within 120 minute ozonation and showed slow decrease upon longer ozonation. Abundance of total heterotrophic bacteria in each fraction was in the following order regardless of ozonation time: small>medium>large fractions. Difference in microbial abundance among the fractions was smaller as ozonation time increased.

• Mycobiology
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• v.49 no.5
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• pp.454-460
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• 2021

Daecheongdo and Socheongdo Islands are located in the West Sea of Korea, 210 km away from land, and are military border areas very close to North Korea, making them difficult to access. Although the ecosystem of the islands is relatively well preserved due to the lack of accessibility, research on fungi of the regions is insufficient. Therefore, we aimed to investigate indigenous fungi in these geographically and geopolitically constrained regions. A survey of the indigenous fungal diversity of the islands was conducted in 2018. All specimens were identified at the species level based on morphological and molecular analyses. Among them, six macrofungi-namely, Agaricus menieri, Crepidotus praecipuus, Dichomitus squalens, Hortiboletus amygdalinus, Melanoleuca friesii, and Trametes lactinea-were not previously reported in Korea. Considering that the proportion of unrecorded species is high in the survey area and period as well as the number of samples collected, similar research on adjacent islands may be necessary.

• Journal of Species Research
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• v.11 no.4
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• pp.310-320
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• 2022

As a subset study to discover indigenous prokaryotic species in Korea, we isolated 20 bacterial strains and assigned them to the phyla Actinobacteria, Bacteroidota, Firmicutes, and Proteobacteria. From the high 16S rRNA gene sequence similarity (≥98.7%) and formation of a robust phylogenetic clades, we determined that each strain belonged to independent, predefined bacterial species. There are no official reports of these 20 species in Korea; therefore, 7 strains of the Actinobacteria, 2 strain of the Bacteroidota, 3 strains of the Firmicutes, and 8 strains of the Firmicutes are described in Korea for the first time. Gram reaction, colony and cell morphology, basic biochemical characteristics, and isolation sources are also described in the species description section.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.1
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• pp.35-41
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• 2009

This study was conducted to investigate feasibility of feedstuff for animal using food waste by fermentation mechanism of indigenous microorganism. To achieve this purpose, indigenous bacteria was isolated from soils to use as an inoculant. Enzyme test was performed to verify activity of amylase, protease and lipase using isolated bacteria. Bacteria(H1, D1), which vigorously express the enzyme activity, was selected and used in the fermentation experiments of food waste. From the analysis of 16s rDNA sequencing, H1 and D1 were identified as Bacillus subtilis and Paenibacillus polymyxa, respectively. In the fermentation experiment, food waste was mixed with rice bran and popped rice to control moisture and nutrient content. Isolated bacteria(B. subtilis and P. polymyxa) was used as an inoculant. From the measured data such as temperature, pH and ORP, it can be verified that food waste adding the indigenous bacteria was effectively fermented. From the nutritional analysis of manufactured feedstuff, it showed that the contents of crude protein, crude fat and crude fiber were enough to use as feedstuff for animal. In addition, harmful components such as Pb, Hg, Cd, aflatoxin and salmonella concentration were not exceeded permitted standards. Therefore, fermented food waste using indigenous bacteria can be used as feedstuff.

• Mycobiology
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• v.45 no.4
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• pp.286-296
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• 2017

Ulleung Island is a biodiversity hotspot in South Korea. During a survey of indigenous fungal species from Ulleung Island conducted from 2015 to 2016, we discovered 10 unrecorded macrofungi in Korea. These macrofungi were identified to the species level using morphological features and phylogenetic analysis based on the internal transcribed spacer region: Deconica phyllogena, Mycena zephirus, Phaeomarasmius proximans, Phlebia radiata, Pluteus semibulbosus, Postia alni, Resinicium pinicola, Scytinostroma portentosum, Tricholomopsis flammula, and Tyromyces kmetii. We also provide detailed morphological descriptions for these 10 species.