• Korean Journal of Plant Taxonomy
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• v.32 no.3
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• pp.257-292
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• 2002

Morphological characters of sections Foetidae(one taxon), Arenariae(one taxon) and Multiflorae(six taxa) of genus Carex(Cyperaceae) were reexamined. The epidermal patterns of perigynium, achene and leaf were investigated using by a scanning electron microscope(SEM) and a light microscope(LM). Morphological characters, such as length and width of stem, leaf, leaf sheath, bract, spike, scale, perigynium and beak of perigynium, length of spike peduncle, size and frequency of stomatal complex of leaf, number of bract, shape of stem transection, scale and apex of scale, beak and base of perigynuim, achene, epidermal cell and cell wall of perigynium, achene, leaf epidermal patterns(fundamental epidermal cell and cell wall, silica body, subsidiary cell), hair, papillae present/absent of perigynium, and leaf were useful for the identification of observed eight taxa. According to the current study, examined eight taxa of sections Foetidae, Arenariae and Multiflorae were distinct from each other with respect to length and width of stem, leaf, bract, perigynium, perigynium beak, length of spike peduncle, shape of bract, scale and apex of scale, perigynium, perigynium beak, hair presence/absence of perigynium and leaf. A key based on data was presented here.

• Korean Journal of Plant Taxonomy
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• v.34 no.3
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• pp.245-264
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• 2004

For nine taxa of the genus Carex which consist of C. arenicola, C. chordorhiza, C. curta, C. gibba, C. laevissima, C. leiorhyncha, C. neuromrpa, C. maakii and C. remouscula with mixed pistillate and staminate flowers, morphological characters such as inflorescense, spikelet, inflorescence bract, utricle, pistillate and staminate scales, achene, length between two spikelets were observed to find useful characters for their identification. Especially, the shape and the number of spikelet were very useful characters to divide the treated nine taxa into two groups, the their keys were prepared. The first group was comprised of five species of C. arenicola, C. chordorhiza, C. curta, C. gibba, and C. remouscula, which were characterized by broadly oboval or narrowly elliptical shape of spikelet, and 3-9 spikelets per infIorescence and gradual decrease in length between two spikelets. The second group was composed of four species of C. laevissima, C. leiorhyncha, C. neurocarpa, C. maakii, which were distinguished by oval shape of spikelet, and 17-20 spikelets per infIorescence and repetition of increase.

• Research in Plant Disease
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• v.25 no.3
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• pp.143-148
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• 2019

An outbreak of new disease with leaf and stem blight symptom occurred at bracken-growing fields in Namhae-gun, Gyeongsangnam-do, Korea during the last 4 years. This new disease caused significant yield losses on bracken production in this area. We have collected diseased leaves and stems showing the blight symptom in May, July, and October 2018 to investigate causal pathogens. A total of 92 fungal isolates were obtained from the diseased samples and their pathogenicity was tested on healthy bracken leaves. From the total isolates, 22 isolates were able to produce the leaf blight symptom similar to the original one found in the fields. To identify two fungal pathogens which showed higher virulence levels compared to other pathogenic isolates, we constructed phylogenetic trees using the nucleotide sequences of genes for ribosomal RNA, RNA polymerase beta subunit, beta tubulin, and internal transcribed region. Most phylogenetic trees constructed indicate that both isolates, which are identical to each other, reside in a clade of the genus Didymella and possibly similar to D. rumicicola or D. acetosellae. Nevertheless, the exact identification of these pathogens at the species level needs further investigations. This is the first report of a blight disease on bracken by Didymella sp.

• Journal of odor and indoor environment
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• v.17 no.4
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• pp.355-361
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• 2018

Mold grows more easily when humidity is higher in indoor spaces, and as such is found more often on wetted areas in housing such as walls, toilets, kitchens, and poorly managed spaces. However, there have been few studies that have specifically assessed the level of mold in the indoor spaces of water-damaged housing in the Republic of Korea. We investigated the levels of airborne mold according to the characteristics of water damage types and explored the correlation between the distribution of mold genera and the characteristics of households. Samplings were performed from January 2016 to June 2018 in 97 housing units with water leakage or condensation, or a history of flooding, and in 61 general housing units in the metropolitan and Busan area, respectively. Airborne mold was collected on MEA (Malt extract agar) at flow rate of 100 L/min for 1 min. After collection, the samples were incubated at $25^{\circ}C$ for 120 hours. The cultured samples were counted and corrected using a positive hole conversion table. The samples were then analyzed by single colony culture, DNA extraction, gene amplification, and sequencing. By type of housing, concentrations of airborne mold were highest in flooded housing, followed by water-leaked or highly condensed housings, and then general housing. In more than 50% of water-damaged housing, the level of airborne mold exceeded the guideline of Korea's Ministry of Environment ($500CFU/m^3$). Of particular concern was the fact that the I/O ratio of water-damaged housing was greater than 1, which could indicate that mold damage may occur indoors. The distribution patterns of the fungal species were as follows: Penicillium spp., Cladosporium spp. (14%), Aspergillus spp. (13%) and Alternaria spp. (3%), but significant differences of their levels in indoor spaces were not found. Our findings indicate that high levels of mold damage were found in housing with water damage, and Aspergillus flavus and Penicillium brevicompactum were more dominant in housing with high water activity. Comprehensive management of flooded or water-damaged housing is necessary to reduce fungal exposure.

• Plant Breeding and Biotechnology
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• v.5 no.4
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• pp.334-343
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• 2017

Eclipta prostrata and E. alba are annual herbal medicinal plants and have been used as Chinese medicinal tonics. Both species are widely distributed in tropical and subtropical regions as well as in Korea. Both species have similar morphological features but E. alba has smoother leaf blade margins compared with E. prostrata. Although both species are utilized as oriental medicines, E. prostrata is more widely used than E. alba. Morphological semblances have confounded identification of either species. Here, we report the complete chloroplast genomes of both species to provide an authentication system between the two species and understand their diversity. Both chloroplast genomes were 151,733-151,757 bp long and composed of a large single copy (83,285-83,300 bp), a small single copy (18,283-18,346 bp), and a pair of inverted repeats (25,075-25,063 bp). Gene annotation revealed 80 protein coding genes, 30 tRNA genes and four rRNA genes. A phylogenetic analysis revealed that the genus Eclipta is grouped with Heliantheae tribe species in the Asteraceae family. A comparative analysis verified 29 InDels and 58 SNPs between chloroplast genomes of E. prostrata and E. alba. The low chloroplast genome sequence diversity indicates that both species are really close to each other and are not completely diverged yet. We developed six DNA markers that distinguish E. prostrata and E. alba based on the polymorphisms of chloroplast genomes between E. prostrata and E. alba. The chloroplast genome sequences and the molecular markers generated in this study will be useful for further research of Eclipta species and accurate classification of medicinal herbs.

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

• Microbiology and Biotechnology Letters
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• v.51 no.4
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• pp.517-525
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• 2023

The emergence and spread of multidrug-resistant Pseudomonas aeruginosa (MRPA) have become a serious problem worldwide. The involvement of metallo-β-lactamases (MBLs) in inducing carbapenem resistance is particularly acute. However, unlike other members of the Enterobacteriaceae genus, new clones of P. aeruginosa are constantly emerging and rapidly replacing previously prevalent dominant clones. Therefore, this study aimed to perform antimicrobial resistance gene analysis, integron gene cassette analysis using DNA sequencing, and plasmid transfer analysis by conjugation to investigate the antimicrobial resistance dynamics of 18 P. aeruginosa strains isolated from various medical samples at a general hospital in Busan from September 2017 to September 2019. All 18 strains showed extensively drug-resistant (XDR) phenotype and were resistant to most antibiotics, except colistin (100%) but were susceptible to aztreonam (22.2%) and ceftazidime (16.6%). Approximately 66.7% of the strains had Class 1 integrons showing various antimicrobial resistances. Notably, IMP-6 ST235 (66.7%), VIM-2 ST357 (16.7%), and IMP-1 ST446(16.7%) were identified. The identification of IMP-1-producing ST446, previously unreported in Korea, is noteworthy considering the emergence and prevalence of another MRPA high-risk clone.

• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.293-299
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• 2006

A survey was conducted to find out the major plant parasitic nematode in Chrysanthemum morifolium fields in Korea from May to June in 2005. A genus of Pratylenchus was determined as the most important plant parasitic nematode based on analysis of total 50 samples from 8 cities of chrysanthemum field. Pratylenchus showed 86% occurrence rate and average numbered 1,095 per 200cc soils and 1g root. Five Pratylenchus isolates, 'Muan', 'Masan', 'Tean', 'Gumi', 'Jeongup', were selected for the molecular identification of the species of Pratylenchus, and ITS and D3-28S ribosomal DNA were amplified by PCR. For the ITS, only 'Muan' isolate was differentiated by total 1 kb PCR amplification, which was 200 bp larger than all the other isolates. There was no size variation in amplified D3-28S rDNA and all isolate represented approximately 320 bp of PCR product. Sequence data of D3-28S rDNA were analysed by MegAlign program in DNASTAR software and phylogenetic tree was constructed. Sequence homology was 100% between 'Gumi' isolate and 'Tean' isolate and 'Jeongup' isolate was also close to these isolates by 99.7% sequence homology. 'Gumi', 'Tean' group and 'Jeongup' isolate were determined to be closely related to Pratylenchus vulnus by 96.7% and 96.3% similarity in respectively. D3 sequence of 'Masan' isolate was 100% identical to P. penetrans, and 'Muan' isolate showed 99.7% similarity to P. brachyurus. This result was congruent with the branch divergence pattern shown in phylogenetic tree.

• Food Science and Preservation
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• v.22 no.3
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• pp.443-451
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• 2015

This study was carried out to investigate the quality characteristics and identification of acetic acid bacteria for black waxy rice vinegar. Eight (8) strains of acetic acid bacteria were isolated for the production of acetic acid and their acidities were then compared with commercial acetic acid bacteria. Among them, F1, H4, and two types of commercial bacteria (four best strains by vinegar zymogen) were selected. After analyzing the 16S rRNA sequence, both F1 and H4 strains were identified as acetobacter genus. Therefore, the F-1 and H-4 strains were named as Acetobacter sp. F-1 and Acetobacter sp. H-4, respectively. Acidity of black waxy rice vinegar during fermentation was steadily increased up to 16 days and the acidity was then constant. Total acidity content was higher when used FV-1 strain. In the results of Hunter's color value of black waxy vinegar, L value was at 75.01 to 80.11, while (+a) value was at 3.34 to 3.92, and (+b) value was at 12.84 to 18.09. The major organic acid of the black waxy vinegar was acetic acid. The total organic acid content was high when used H-4, F-1, C-2 and C-1 strains. The total free amino acid content of the black waxy vinegar by strain was the highest (351.43 mg%) of F-1 vinegar strain, and the lowest (247.74 mg%) of C-2 vinegar strain. A sensory evaluation of black waxy vinegar indicated that F-1 vinegar strain was better than the other samples in aspect of flavor, color, and overall preference.

• Korean Journal of Microbiology
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• v.52 no.2
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• pp.192-201
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• 2016

Recently, Psychrobacter sp. ArcL13 strain showing the extracellular lipase activity was isolated from the Chuckchi Sea of the Arctic Ocean. However, due to the low expression levels of the enzyme in the natural strain, the production of recombinant lipase is crucial for various applications. Identification of the gene for the enzyme is prerequisite for the production of the recombinant protein. Therefore, in the present study, a novel lipase gene (ArcL13-Lip) was isolated from Psychrobacter sp. ArcL13 strain by gene prospecting using PCR, and its complete nucleotide sequence was determined. Sequence analysis showed that ArcL13-Lip has high amino acid sequence similarity to lipases from bacteria of some Psychrobacter genus (84-90%) despite low nucleotide sequence similarity. The lipase gene was cloned into the bacterial expression plasmid and expressed in E. coli. SDS-PAGE analysis of the cells showed that ArcL13-Lip was expressed as inclusion bodies with a molecular mass of about 35 kDa. Refolding was achieved by diluting the unfolded protein into refolding buffers containing various additives, and the highest refolding efficiency was seen in the glucose-containing buffer. Refolded ArcL13-Lip showed high hydrolytic activity toward p-nitrophenyl caprylate and p-nitrophenyl decanoate among different p-nitrophenyl esters. Recombinant ArcL13-Lip displayed maximal activity at $40^{\circ}C$ and pH 8.0 with p-nitrophenyl caprylate as a substrate. Activity assays performed at various temperatures showed that ArcL13-Lip is a cold-active lipase with about 40% and 73% of enzymatic activity at $10^{\circ}C$ and $20^{\circ}C$, respectively, compared to its maximal activity at $40^{\circ}C$.