• Weed & Turfgrass Science
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• v.2 no.3
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• pp.306-311
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• 2013

Pythium blight occurred by Pythium aphanidermatum on chewing fescue cv. "Jamestowm II" from early June, 2010 and 2011 at the test field in Daegu University in Gyeongbuk Province, Korea. Disease symptoms on the turfgrass were leaf blights dying from the leaf tip and root rot, which appeared patches of brown to dark brown color or gray brown color in the field. The pathogens (40-1 isolate) of Pythium blight was isolated from the diseased leaf and crown tissue and cultured on potato-dextrose agar (PDA) for identification. Lobulate sporangia were inflated, complex structures, and filamentous sporangia were usually indistinguishable from vegetative hyphae. Sequences of ribosomal RNA gene of the fungus were homologous with similarity of 100% to those of P. aphanidermatum isolates in GenBank database. Pathogenicity was also confirmed on the chewing fescue, creeping betgrass and Kentucky bluegrass by Koch's postulates. This is the first report of Pythium blight on chewing fescue caused by P. aphanidermatum in Korea.

• Korean journal of food and cookery science
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• v.31 no.1
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• pp.9-17
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• 2015

Shindari is a traditional fermented drink of Jeju in Korea, which is made with boiled barley and nuruk for short fermentation periods. This study determined chemical, microbiological, and sensory characteristics of the modified Shindari with 15% carrots as an additive (carrot Shindari), and this study compared it with a traditional Shindari as a control. After fermentation at $30^{\circ}C$ for a day, the pHs of the carrot Shindari and traditional Shindari largely decreased, and the total acidities increased in both of the Shindari. The significantly higher scores of Hunter's color values were observed more in carrot Shindari than in traditional Shindari. Also, carrot Shindari (0.4954 g/100 g) had a significantly higher content of vitamin C than traditional Shindari (0.0030 g/100 g). The most abundant free sugar and organic acid were glucose and lactic acid, respectively, in both of the Shindari. The total numbers of bacteria, fungi and lactic-acid bacteria in both samples increased by log 3 CFU/mL after fermentation. Based on 16S ribosomal RNA gene analysis, the dominant lactic-acid bacteria was Pediococcus acidilactici in both samples. The DPPH (1.1-diphenyl-2-picrylhydrazyl) radical scavenging activity of carrot Shindari (60.13%) was higher than that of traditional Shindari (23.70%). In sensory evaluations (taste, flavor, color, and overall acceptance), the carrot Shindari had higher scores in all these values. In this study, the modified Shindari with carrot presenting high sensory characteristic as well as chemical and microbiologic characteristics provide an opportunity to improve the application of a traditional fermented drink of Jeju, Shindari.

• Archives of Plastic Surgery
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• v.39 no.1
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• pp.18-24
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• 2012

Background : Infection caused by rapidly growing mycobacteria (RGM) is not uncommon, and the prevalence of RGM infection has been increasing. Clinical diagnosis is difficult because there are no characteristic clinical features. There is also no standard antibiotic regimen for treating RGM infection. A small series of patients with RGM infections was studied to examine their treatments and outcomes. Methods : A total of 5 patients who had developed postoperative infections from January 2009 to December 2010 were retrospectively reviewed. Patients were initially screened using a mycobacteria rapid screening test (polymerase chain reaction [PCR]-reverse blot hybridization assay). To confirm mycobacterial infection, specimens were cultured for nontuberculous mycobacteria and analyzed by 16 S ribosomal RNA and rpoB gene PCR. Results : The patients were treated with intravenous antibiotics during hospitalization, and oral antibiotics were administered after discharge. The mean duration of follow-up was 9 months, and all patients were completely cured of infection with a regimen of a combination of antibiotics plus surgical treatment. Although none of the patients developed recurrence, there were complications at the site of infection, including hypertrophic scarring, pigmentation, and disfigurement. Conclusions : Combination antibiotic therapy plus drainage of surgical abscesses appeared to be effective for the RGM infections seen in our patients. Although neither the exact dosage nor a standardized regimen has been firmly established, we propose that our treatment can provide an option for the management of rapidly growing mycobacterial infection.

• Journal of Applied Biological Chemistry
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• v.62 no.4
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• pp.441-446
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• 2019

The assortment of endophytic lactic acid bacteria (LAB) in kimchi derives from its raw vegetables, which include Chinese cabbage, radish, welsh onion, onion, garlic, red pepper, and ginger. These vegetables were examined during mulkimchi fermentation using gene-specific multiplex polymerase chain reaction and 16S ribosomal RNA sequence analysis. Sixteen species from five LAB genera (Leuconostoc, Lactobacillus, Lactococcus, Pediococcus, and Weissella) appeared in the raw kimchi materials. Interestingly, nine LAB species were identified in mulkimchi on fermentation day 0 as follows: Leuconostoc carnosum, Leuconostoc citreum, Leuconostoc gelidum, Leuconostoc inhae, Leuconostoc mesenteroides, Lactobacillus plantarum, Lactobacillus sakei, Lactococcus lactis, and Weissella confusa. Seven additional LAB species were present in mulkimchi at fermentation day 9 as follows: Leuconostoc gasicomitatum, Leuconostoc kimchii, Lactobacillus brevis, Lactobacillus curvatus, Lactobacillus pentosus, Pediococcus pentosaceus, and Weissella koreensis. These species corresponded completely with the LAB in kimchi vegetables. Wei. confusa was the predominant LAB during early fermentation (pH 6.20 to 4.98 and acidity 0.20 to 0.64%), while Lac. sakei, Lac. plantarum, and Wei. koreensis became dominant later in fermentation (pH 4.98 to 3.88 and acidity 0.64 to 1.26%). These results collectively demonstrate that the LAB involved in mulkimchi fermentation originates from the raw vegetables examined.

• Journal of Food Hygiene and Safety
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• v.15 no.1
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• pp.51-54
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• 2000

In the 5'-flanking region of the D-AAT, AspAT and AlaDH gene, I found three or two pairs of sequences(designated as Pl, P2, P3) which show significant similarity to the E.coli consensus sequences of -35 and -10 for promoters. The spacing between -35 and -10 is 16 to 18bp in all the three putative promoters Pl, P2 and P3 which is in good agreement with the preferred spacer length in E.coli and in B.subtilis. Therefore, the putative promoters may also function to increase the efficiency of transcriptional initiation. The most stable, double-helical“Shine-Dalgarno”pairing is formed with a free energy change(ΔG) of -13.0 kcal/mol, -9.6 kcal/mol, -15.8 kcal/mol.

• Journal of Life Science
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• v.11 no.2
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• pp.74-80
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• 2001

The nucleotide sequences of the internal transcribed spacer regions (ITS1 and ITS2) of ribosomal DNA (rDNA), and the 5.85 rRNA gene, have been determined for 13 strains of dinoflagellates in order to analyze the phylo-genetic relationship. The DNA sequences contained considerable variation in the ITS regions, but little in the 5.85 rDNA. In addition, the ITS1 was more variable than the ITS2 in all species examined. The nucleotide length of this region varied from 519 bp to 596 bp depending on the taxa. The investigated taxa were divided into three large groups based on the ITS length, i. e., a group with short ITS region (A. fraterculus and Alexandrium sp.), a with ITS region group (P. micans, P. minimum and P. triestinum) and a with ITS region group (G. impudicum, C. polykrikoides, G. sanguineum, G. catenatum and H. triquetra). The relationship between nucleotide length of ITS1 and that of ITS2 was negative, whereas G+C content and nucleotide length showed positive correlation. In phylogenetic analyses producing NJ trees, the topology was similar cluster and clearly divided the taxa into three groups based on 5.8S rDNA that were similar to those based on morphological characteristics. In particular, G. impudicum was more closely related to G. catenatum than to C. polykrikoides using phylogenetic analysis. From this study, we chew that the length of ITS region contributes to discriminate Korean harmful algal species and ITS analysis is a useful method for resolving the systematic relationships of dinoflagellates.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1285-1290
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• 2018

Objective: This study shows the effects of dietary fiber levels on cecal microbiota composition in geese at day 70 according to pyrosequencing of the 16S ribosomal RNA gene. Methods: A total of 468 1-day-old healthy male Yangzhou goslings with similar body weight were randomly divided into 3 groups with 6 replicates per group and 26 geese per replicate. Geese were fed diets with fiber levels of 2.5% (low fiber level diet, Group I) and 6.1% (Group III) during days 1-70, respectively, or 4.3% for days 1-28 and 6.1% for days 29-70 (Group II). Results: Low fiber level diet decreased body weight, average daily gain during, increased lower feed conversation rate of geese during day 1 to 70 (p<0.05). Low fiber level diet decreased the total operational taxonomic units, Chao1 index and Shannon index, whereas increased the Simpson index of cecal microbiota in geese at day 70. Low fiber level diet decreased the relative abundance of Bacteroidetes, Firmicutes, Bacteroides, and Paraprevotella in cecum of geese at day 70. The similarity of cecal microbiota between low fiber level diet group and other groups was smaller. Conclusion: This study indicates that the low fiber level diet decreased diversity of microbiota, and relative abundance of some beneficial microbiota in cecum of geese at day 70, implying that the low fiber level diet has negative influence on performance by altering the diversity and population of cecal microbiota in geese.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1373-1380
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• 2018

Objective: This study was designed to investigate the effects of temperature and storage time on the evolution of bacterial communities in swine manure. Methods: Manure was stored at $-20^{\circ}C$, $4^{\circ}C$, $20^{\circ}C$, or $37^{\circ}C$ and sampled at 7-day intervals over 28 days of storage, for a total of 5 time points. To assess the bacterial species present, 16S ribosomal RNA gene sequences were analyzed using pyrosequencing. Results: After normalization, 113,934 sequence reads were obtained, with an average length of $466.6{\pm}4.4bp$. The diversity indices of the communities reduced as temperature and storage time increased, and the slopes of rarefaction curves decreased from the second week in samples stored at $-20^{\circ}C$ and $4^{\circ}C$. These results indicate that the richness of the bacterial community in the manure reduced as temperature and storage time increased. Firmicutes were the dominant phylum in all samples examined, ranging from 89.3% to 98.8% of total reads, followed by Actinobacteria, which accounted for 0.6% to 7.9%. A change in community composition was observed in samples stored at $37^{\circ}C$ during the first 7 days, indicating that temperature plays an important role in determining the microbiota of swine manure. Clostridium, Turicibacter, Streptococcus, and Lactobacillus within Firmicutes, and Corynebacterium within Actinobacteria were the most dominant genera in fresh manure and all stored samples. Conclusion: Based on our findings, we propose Clostridium as an indicator genus of swine manure decomposition in an anaerobic environment. The proportions of dominant genera changed in samples stored at $20^{\circ}C$ and $37^{\circ}C$ during the fourth week. Based on these results, it was concluded that the microbial communities of swine manure change rapidly as storage time and temperature increase.

• The Plant Pathology Journal
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• v.36 no.3
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• pp.244-254
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• 2020

Gom-chwi (Ligularia fischeri) is severely infected with Phytophthora drechsleri, the causal organism of Phytophthora root rot, an economically important crop disease that needs management throughout the cultivation period. In the present study, Phytophthora root rot was controlled by using bacterial isolates from rhizosphere soils collected from various plants and screened for antagonistic activity against P. drechsleri. A total of 172 bacterial strains were isolated, of which, 49 strains showed antagonistic activities by dual culture assay. In the seedling assay, six out of the 49 strains showed a predominant effect on suppressing P. drechsleri. Among the six strains, the ObRS-5 strain showed remarkable against P. drechsleri when treated with seed dipping or soil drenching. The ObRS-5 strain was identified as Enterobacter asburiae based on 16S ribosomal RNA gene sequences analysis. The bacterial cells of E. asburiae ObRS-5 significantly suppressed sporangium formation and zoospore germination in P. drechsleri by 87.4% and 66.7%, respectively. In addition, culture filtrate of E. asburiae ObRS-5 also significantly inhibited sporangium formation and zoospore germination by 97.0% and 67.6%, respectively. Soil drenched bacterial cells, filtrate, and culture solution of E. asburiae ObRS-5 effectively suppressed Phytophthora root rot by 63.2%, 57.9%, and 81.1%, respectively. Thus, E. asburiae ObRS-5 could be used as a potential agent for the biological control of Phytophthora root rot infecting gom-chwi.

• Journal of Microbiology and Biotechnology
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• v.31 no.11
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• pp.1526-1532
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• 2021

Suaeda australis, Phragmites australis, Suaeda maritima, Suaeda glauca Bunge, and Limonium tetragonum in the Seocheon salt marsh on the west coast of the Korean Penincula were sampled in order to identify the endophytes inhabiting the roots. A total of 128 endophytic fungal isolates belonging to 31 different genera were identified using the fungal internal transcribed spacer (ITS) regions and the 5.8S ribosomal RNA gene. Fusarium, Paraconiothyrium and Alternaria were the most commonly isolated genera in the plant root samples. Various diversity indicators were used to assess the diversity of the isolated fungi. Pure cultures containing each of the 128 endophytic fungi, respectively, were tested for the plant growth-promoting abilities of the fungus on Waito-C rice germinals. The culture filtrate of the isolate Lt-1-3-3 significantly increased the growth of shoots compared to the shoots treated with the control. Lt-1-3-3 culture filtrate was analyzed and showed the presence of gibberellins (GA₁ 2.487 ng/ml, GA₃ 2.592 ng/ml, GA₉ 3.998, and GA₂₄ 6.191 ng/ml). The culture filtrate from the Lt-1-3-3 fungal isolate produced greater amounts of GA₉ and GA₂₄ than the wild-type Gibberella fujikuroi, a fungus known to produce large amounts of gibberellins. By the molecular analysis, fungal isolate Lt-1-3-3 was identified as Gibberella intermedia, with 100% similarity.