• Journal of Species Research
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• v.11 no.2
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• pp.89-93
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• 2022

Three heterotrophic euglenids from marine water column (Seodo port, Yeosu) and freshwater sediment (Seodong-chun, Incheon), Korea were identified as Entosiphon oblongum Cavalier-Smith and Vickerman, 2016; Euglena longa (Pringsheim, 1936) Marin and Melkonian, 2003; and Keelungia pulex Chan and Moestrup, 2013 based on morphological characters and 18S rDNA sequence analysis. These species are reported taxonomically for the first time from Korea and are described with micrographs. Diagnoses of these species are as follows. Entosiphon oblongum: phagotrophic, gliding, size in vivo, 23.1-29.3 ㎛ (Avg. 26.5 ㎛, n=30) long, ovate with a protrusive feeding siphon (apparatus), several deep grooves and two heterodynamic flagella. Euglena longa: osmotrophic, swimming, size in vivo, 32.3-52.2 ㎛ (Avg. 42.2 ㎛, n=26) long, elongated with many paramylum granules and two flagellar. Keelungia pulex: phagotrophic, gliding, size in vivo, 13.5-19.7 ㎛(Avg. 16.4 ㎛, n=97) long, oblong to ovoid with a hook-shaped ingestion apparatus, several dorsal ridges and two flagella.

• Microbiology and Biotechnology Letters
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• v.46 no.1
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• pp.68-76
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• 2018

Actinobacterial strains isolated from Cow feces were studied for their antifungal attributes against phytopathogens and industrially important enzymes. A total of 30 Actinobacterial strains were obtained from 10 samples of cow feces. All the strains were belonging to the genera Streptomyces on the basis of morphological and chemotaxonomic analysis. During preliminary screening, out of 30 strains, 15 strains (50%) showed antifungal activity against five fungal phytopathogens including Aspergillus niger, Fusarium solani, Fusarium oxysporum, Macrophomina phaseolina and Rhizoctonia solani. While, isolate GBTCF-26 was found to be most active against R. solani with 62.2% inhibition of fungal mycelium, GBTCF-09 was prominent against F. solani and F. oxysporum with percent inhibition of 61.1% and 58.8%, respectively. Out of 30 strains, 19 (63.3%), 16 (53.3%), 11 (36.7%), 10 (33.3%), 4 (13.3%) and 8 (26.7%) strains were producing amylase, caseinase, gelatinase, lipase, chitinase and cellulose, respectively. The selected strains, GBTCF-09, GBTCF-21 and GBTCF-26, were identified as Streptomyces sp. on the basis of their 16S rDNA sequence. The study supports the idea that the Actinobacteria from unique niches (Cow feces) possess the production potential of industrially important enzymes including bioactive molecules.

• The Korean Journal of Mycology
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• v.43 no.3
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• pp.196-199
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• 2015

The occurrence and characterization of yeast isolated from Korean traditional nuruk were investigated. Sequences of the D1/D2 domain of the 26S rDNA were identical for a strain examined and had a similarity value of 100% compared to sequences of the type strain of Saccharomyces cerevisiae (NRRL Y-12632). The isolate able to assimilate with trehalose, raffinose, and methyl-glucoside assimilate was also capable of glucose, galactose, maltose, and sucrose fermentation. It did not proliferate at $40^{\circ}C$ or above, but was able to grow in concentration of 50% glucose and 10% NaCl. By combining nucleotide sequence, morphological observation, and physiological characteristics, the isolate was identified as S. cerevisiae.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.311-314
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• 2005

Approximately twelve hundred strains of Actonomycetes isolated from domestic soli were tested for their ability to produce extracellular phytase. Of all these isolates a strain, YB-26, that had the highest potential for phytase activity was chosen. The nucleotide sequence of 16S rDNA of the isolate YB-26 showed the highest similarity to that of strains beloning to genus Streptomyces. The partially purified extracellular phytase was obtained from the culture filtrate of Streptomyces sp. YB-26 grown on GSM broth by ammonium sulfate precipitation (15-70%), DEAE-Sepharose column and Q-Sepharose column chromatography. The partially purified enzyme showed the maximum activity for hydrolysis of phyate at $60^{\circ}C$ and pH 7.0, and retained 90% of its maximum activity at the range of pH $6.0{\sim}8.0$. It was thermolabile and its thermostability did not increase in the presence of calcium chloride.

• The Korean Journal of Mycology
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• v.44 no.4
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• pp.252-258
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• 2016

In this study, endophytic fungi were isolated from the leaves of five species of woody plants in Jeju, Korea, namely Chamaecyparis obtusa, Cryptomeria japonica, Torreya nucifera, Ilex crenata, and Camellia japonica. The isolated fungal endophytes were identified based on their morphological and molecular characteristics including a sequence analysis of the internal transcribed spacer and 26S regions of rDNA and ${\beta}$-tubulin genes. Ten species of fungal endophytes have not been previously reported in Korea, namely Mycosphaerella aleuritidis, Neofusicoccum eucalyptorum, Neofusicoccum parvum, Phyllosticta citrichinensis, Phyllosticta cryptomeriae, Phomopsis cotoneastri, Sphaerulina rhododendricola, Guignardia mangiferae, Lophodermium jiangnanense, and Lophodermium minus.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1439-1445
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• 2016

A yellow, rod-shaped, non-motile, gram-negative, and strictly aerobic bacterial strain, designated LPB0005^T, was isolated from a marine gastropod, Reichia luteostoma. Here the genome sequence was determined, which comprised 3,395,737 bp with 2,962 protein-coding genes. The DNA G+C content was 36.3 mol%. The 16S rRNA gene sequence analysis indicated that the isolate represents a novel genus and species in the family Flavobacteriaceae, with relatively low sequence similarities to other closely related genera. The isolate showed chemotaxonomic properties within the range reported for the family Flavobacteriaceae, but possesses many physiological and biochemical characteristics that distinguished it from species in the closely related genera Ulvibacter, Jejudonia, and Aureitalea. Based on phylogenetic, phenotypic, and genomic analyses, strain LPB0005^T represents a novel genus and species, for which the name Cochleicola gelatinilyticus gen. nov., sp. nov. is proposed. The type strain is LPB0005^T (= KACC 18693^T = JCM 31218^T).

• Research in Plant Disease
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• v.19 no.1
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• pp.12-20
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• 2013

To isolate antagonistic bacteria against sclerotinia rot of lettuce, caused by Sclerotinia sclerotiorum, soil samples were collected from the diseased greenhouse field in Namyangju city, Gyeong-gi province from 2007 to 2008. A total of 196 bacterial isolates were isolated using serial dilution method. In dual culture assay in vitro, 26 isolates showed more than 80% of inhibition rates of mycelial growth of S. sclerotiorum. Based on 16S rDNA sequence analysis, the 26 isolates were identified as Bacillus megaterium, B. cereus, B. subtilis, Arthrobacter nicotianae, A. ramosus, Pseudomonas filiscindens, Stenotrophomonas maltophilia, Brevibacterium frigoritolerans and Sphingobacterium faecium. The 26 isolates inhibited the mycelial growth of S. sclerotiorum up to 80% and the sclerotial germination 0-100%. In the greenhouse pot test of ten isolates conducted in summer, 2 isolates B. megaterium (DK6) and B. cereus (C210) showed control efficacy on sclerotia viability of S. sclerotiorum, 20% and 35%, respectively. In the greenhouse pot test in winter, the disease incidence of the control group was 80%, whereas those of 9 isolates among 26 were approximately 20%. From the result, the 9 isolates are expected as potentially antagonistic bacteria for biological control of sclerotinia rot of lettuce caused by S. sclerotiorum.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.116-124
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• 2006

In this study was performed to analyze quantitatively the number of viable but non-culturable bacteria in the Pine and Quercus forest soil by improved direct viable count (DVC) and plate count (PC) methods. The number of living bacteria of Pine and Quercus forest soil by PC method were less then 1% of DVC method. This result showed that viable but non-culturable (VBNC) bacteria existed in the forest soil with high percentage. Diversity and structure of VBNC bacterial populations in forest soil were analyzed by direct extracting of DNA and 16S rDNA-ARDRA from Pine and Quercus forest soil. Each of them obtained 111 clones and 108 clones from Pine and Quercus forest soil. Thirty different RFLP types were detected from Pine forest soil and twenty-six different RFLP types were detected from Quercus forest soil by HeaIII. From ARDRA groups, dominant clones were selected for determining their phylogenetic characteristics based on 16S rDNA sequence. Based on the 16S rDNA sequences, dominant clones from ARDRA groups of Pine forest soil were classified into 7 major phylogenetic groups ${\alpha}$-proteobacteria (12 clones), ${\gamma}$-proteobacteria (3 clones), ${\delta}$-proteobacteria (1 clone), Flexibacter/Cytophaga (1 clone), Actinobacteria (4 clones), Acidobacteria (4 clones), Planctomycetes (5 clones). Also, dominant clones from ARDRA groups of Quercus forest soil were classified into 6 major phylogenetic groups : ${\alpha}$-proteobacte,ia (4clones), ${\gamma}$-proteobacteria (2 clones), Actinobacteria (10 clones), Acidobacteria (8 clones), Planctomycetes (1 clone), and Verrucomicobia (1 clone). Result of phylogeneric analysis of microbial community from Pine and Quercus forest soils were mostly confirmed at uncultured or unidentified bacteria, VBNC bacteria of over 99% existent in forest soil were confirmed variable composition of unknown micro-organism.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.10
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• pp.979-985
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• 2010

This study was performed to detect enterococci strain as an indicator of faecal contamination, to identify of 16S rDNA sequence and vancomycin resistance by MIC (Minimum Inhibitory Concentration) test from drinking spring-water samples in Seoul. The detection frequency of enterococci was 42 (19.8%) among 212 samples, and its concentration was ranged from 0 to 110 CFU/100 mL. These results were confirmed the possibility as an indicator microorganisms that similar to the frequency of E. coli detection (t test p-value 0.268, significant level 0.05). Isolated 56 enterococci samples were identified by 16S rDNA sequence data and their NCBI BLAST searching. They were identified to Enterococcus faecalis of 24 samples, E. faecium (10), E. casseliflavus (10), E. gallinarum (3), E. hirae (2), E. durans (2), E. sanguinicola (1). E. faecalis was dominant species that clinical case report of a domestic was similar. Vancomycin resistant enterococci (VRE) of 53 samples showed that vanB and vanC1/C2 type with 2 and 12 case, respectively. These results indicated that the drinking spring-water quarantined to fecal pollution for block out outbreak of gastrointestinal symptom with using such as disinfection process.

• The Korean Journal of Mycology
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• v.49 no.4
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• pp.545-553
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• 2021

In 2021, seven yeast strains were isolated from earthworm (Eisenia andrei) gut samples collected from the Nanji Water Regeneration Center in Goyang City, Gyeonggi Province, Korea. A total of seven yeasts were isolated, of which three strains have not been previously reported in Korea. To identify the yeasts, pairwise sequence comparisons of large subunit (LSU) rDNA sequences were performed using the basic local alignment search tool (BLAST). Assimilation test and cell morphology analysis were performed using the API 20C AUX kit and phase contrast microscope, respectively. Five of the seven strains were assigned to the genus Candida of the order Saccharomycetales of the class Saccharomycetes, and two to the genus Apiotrichum of the order Trichosporonales of the class Tremellomycetes. The yeast strain Candida sojae E2 belongs to the family Debaryomycetaceae, and Apiotrichum laibachii E8 and A. laibachii E9 belong to the family Trichosporonaceae. All strains were cultured in yeast mold agar for three days and showed different colony forms. C. sojae E2 was round and entire shaped, while A. laibachii E8 and A. laibachii E9 was round and convex shaped. This study focuses on the description of the three yeast strains that have not been officially reported in Korea.