• 정보처리학회논문지D
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• 제10D권6호
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• pp.897-906
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• 2003

전통적인 동물 계통수(系統樹)는 초기발생 혈질에 기초하여 몸 구조가 단순한 것에서 복잡한 것으로 동물문(animal phylum)들을 배열하는 것이다. 현재 활발하게 연구 진행되는 분자수준에서의 분자계통 분류학(Molecular Systematics) 연구들이 이런 경향을 재평가하고 새로운 계통과 진화의 의미를 제시하고 있다. 본 논문에서는 한 염기서열로부터 획득할 수 있는 특성 값들을 추출하여 트레이닝 데이터를 생성하고, 생성된 데이터를 기반으로 데이터마이닝 기법중의 하나인 분류기법(classification) 을 사용하여 계통수를 생성하였다. 실험용 데이터는 미토콘드리아 염기서열을 사용하였으며 생물학분야에서 사용하는 분석 프로그램인 MEGA 프로그램을 사용하여 이를 증명하였다. 비록 마이닝을 수행한 결과는 생물학적 실험을 거쳐 정확성을 검증 받아야 하지만 인터넷상에 떠다니는 무수한 유전체들에 대한 유효한 분류기준을 제시할 수 있고 계통수 제작을 위한 실험에 소요되는 많은 시간과 노력들을 줄일 수 있다.

• Journal of Microbiology and Biotechnology
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• 제24권7호
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• pp.888-897
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• 2014

A bacterial community analysis of the gut of Tenebrio molitor larvae was performed using pyrosequencing of the 16S rRNA gene. A predominance of genus Spiroplasma species in phylum Tenericutes was observed in the gut samples, but there was variation found in the community composition between T. molitor individuals. The gut bacteria community structure was not significantly affected by the presence of antibiotics or by the exposure of T. molitor larvae to a highly diverse soil bacteria community. A negative relationship was identified between bacterial diversity and ampicillin concentration; however, no negative relationship was identified with the addition of kanamycin. Ampicillin treatment resulted in a reduction in the bacterial community size, estimated using the 16S rRNA gene copy number. A detailed phylogenetic analysis indicated that the Spiroplasma-associated sequences originating from the T. molitor larvae were distinct from previously identified Spiroplasma type species, implying the presence of novel Spiroplasma species. Some Spiroplasma species are known to be insect pathogens; however, the T. molitor larvae did not experience any harmful effects arising from the presence of Spiroplasma species, indicating that Spiroplasma in the gut of T. molitor larvae do not act as a pathogen to the host. A comparison with the bacterial communities found in other insects (Apis and Solenopsis) showed that the Spiroplasma species found in this study were specific to T. molitor.

• Journal of Microbiology and Biotechnology
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• 제30권11호
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• pp.1640-1650
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• 2020

Colorectal cancer (CRC) is the leading cause of common malignant neoplasm worldwide. Many studies have analyzed compositions of gut microbiota associated with various diseases such as inflammatory bowel diseases (IBD) and colon cancer. One of the most representative bacteria involved in CRC is enterotoxigenic Bacteroides fragilis (ETBF), a species belonging to phylum Bacteroidetes. We used ETBF colonized mice with azoxymethane (AOM)/dextran sulphate sodium (DSS) and zerumbone, a compound with anti-bacterial effect, to determine whether zerumbone could restore intestinal microbiota composition. Four experimental groups of mice were used: sham, ETBF colonized AOM/DSS group, ETBF colonized AOM/DSS group zerumbone 60 mg kg-1 (ETBF/AOM/DSS + Z (60)), and only zerumbone (60 mg kg^-1)-treated group. We performed reversible dye terminators-based analysis of 16S rRNA gene region V3-V4 for group comparison. Microbiota compositions of ETBF/AOM/DSS + Z (60) group and ETBF colonized AOM/DSS group not given zerumbone were significantly different. There were more Bacteroides in ETBF/AOM/DSS + Z (60) group than those in ETBF colonized AOM/DSS group, suggesting that B. fragilis could be a normal flora activated by zerumbone. In addition, based on linear discriminant analysis of effect size (LEfSe) analysis, microbial diversity decreased significantly in the ETBF colonized AOM/DSS group. However, after given zerumbone, the taxonomic relative abundance was increased. These findings suggest that zerumbone not only influenced the microbial diversity and richness, but also could be helpful for enhancing the balance of gut microbial composition. In this work, we demonstrate that zerumbone could restore the composition of intestinal microbiota.

• Journal of Ginseng Research
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• 제36권2호
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• pp.211-217
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• 2012

Endophytic fungi were isolated from various tissues (root, stem, petiole, leaf, and flower stalk) of 3- and 4-year-old ginseng plants (Panax ginseng Meyer) cultivated in Korea. The isolated endophytic fungi were identified based on the sequence analysis of the internal transcribed spacer (ITS), 1-5.8-ITS 2. A morphological characterization was also conducted using microscopic observations. According to the identification, 127 fungal isolates were assigned to 27 taxa. The genera of Phoma, Alternaria and Colletotrichum were the most frequent isolates, followed by Fusarium, Entrophospora and Xylaria. Although 19 of the 27 taxa were identified at the species level, the remainder were classified at the genus level (6 isolates), phylum level (Ascomycota, 1 isolate), and unknown fungal species (1 isolate). Endophytic fungi of 13 and 19 species were isolated from 3- and 4-year-old ginseng plants, respectively, and Phoma radicina and Fusarium solani were the most frequently isolated species colonizing the tissues of the 3- and 4-year-old ginseng plants, respectively. The colonization frequency (CF%) was dependant on the age and tissue examined: the CFs of the roots and stems in the 3-year-old ginseng were higher than the CF of tissues in the 4-year-old plants. In contrast, higher CFs were observed in the leaves and petioles of 4-year-old plants, and endophytic fungi in the flower stalks were only detected in the 4-year-old plants. In conclusion, we detected diverse endophytic fungi in ginseng plants, which were distributed differently depending on the age and tissue examined.

• 농업과학연구
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• 제47권2호
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• pp.219-227
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• 2020

Among insect species, black soldier fly larvae (BSFL) is a promising ingredient for animal feed as a dietary source. Moreover, BSFL contains a high content of lauric acid (C12:0), which has antimicrobial effects. Therefore, this study evaluated the effect of BSFL oil (BSFLO) as a partial or total replacement of soybean oil (SBO) on the cecal microbiota in broilers. A total of 210 male broiler chickens (Ross 308) at one-day of age were randomly allotted to 3 dietary treatments (10 replicates and 7 birds/group): a basal control diet (CON), the basal diet in which SBO was replaced by 50% (50 BSFLO) or 100% (100 BSFLO) BSFLO. At the end of the study (d 35), 18 birds (6 broilers/treatment) were randomly selected and slaughtered. Samples of cecal digesta were collected to verify their cecal microbiota. Overall, 235,978 gene sequences were generated, and a total of 4,398 operational taxonomic units were identified in the three groups. At the phylum level, Firmicutes was the dominant phyla in all three groups. At the genus level, Faecalibacterium was the dominant genera in all the treatments. There were no significant differences in the relative abundances of all the genera between the BSFLO groups and CON. However, the genus Erysipelatoclostridium was more abundant in the 50 BSFLO group than in the CON (p < 0.05). In conclusion, the substitution of SBO with BSFLO in broiler diets had no negative effect on the cecal microbiota of broilers.

• 대한화장품학회지
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• 제41권2호
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• pp.127-134
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• 2015

화장품 및 화장품 함유 방부제에 대한 병원미생물과 사람의 피부서식세균들의 증식에 미치는 효과를 조사하였다. 파라벤, 1,2-헥산디올, 페녹시 에탄올과 같은 방부제를 함유한 토너, 에멀젼, 크림, 유아용크림은 포도상구균, 대장균, 녹농균에 대해 강한 방부효과를 보였으며, 파라벤, 1,2-헥산디올, 페녹시 에탄올과 같은 방부제들은 포도상구균, 대장균, 녹농균과 같은 병원균 및 Staphilococcus epidermidis, Shigella flexneri, Enterobacter aerogenes 등과 같은 일부 피부서식세균에 대한 강한 항균효과를 보였다. 사람의 피부에 페녹시 에탄올 함유 크림을 도포하였을 때, 피부서식 미생물들의 구성이 바뀌었다. 문 수준에서는 Proteobacteria가 증가하였고, 종 수준에서는 4P004125_s가 증가하였고, Propionibacterium humerusii 감소하였다. 이 결과들로부터 파라벤, 1,2-헥산디올, 페녹시 에탄올과 같은 방부제는 병원균에 대한 항균효과를 가짐과 동시에 페녹시 에탄올을 함유한 화장품은 피부세균군집에 변화를 줄 수 있음을 시사하고 있다.

• 생명과학회지
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• 제22권10호
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• pp.1286-1294
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• 2012

섬진강에서 2009년과 2010년 사이의 대형무척추동물에 대한 생물학적 군락 분석을 실시하였다. 조사 정점에 재해 총 10목 24과 106종이 채집이 되었다. 비록 정점별 종과 개체수는 다르지만 조사 시기별로는 정점 간 유의한 차이를 나타내지 않았다. 정점별 우점종은 달랐다. 2009년 5월 정점에 대해 정점 1이 5종인 반면 정점 2는 66종으로 차이를 보였으며 평균 종수는 38.3종이었다. 반면에 정점 2는 2009년 11월에 가장 많은 종수를 나타내었고 정점 3은 가장 낮았다. 대형무척추동물 중에서 절지동물문(Phylum Arthropod)이 종 수준 또는 개체 수준에서 우점이었는데 종 수준으로 5월은 63.2%, 11월은 60.9%였다. 조사 정점에 대한 환경 인자 분석의 결과 대형무척추 동물의 서식에 미치는 인자로 용존산소량(DO), 생물학적 산소요구량(BOD), 화학적 산소요구량(COD)이 중요한 것으로 나타났다. 생물학적 종다양도는 섬진강 상류에서 하류로 갈수록 낮아지는 경향을 나타내었다.

• 한국환경농학회지
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• 제30권4호
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• pp.367-376
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• 2011

논 토양의 미생물 생태 다양성을 조사하기 위한 효과적인 방법으로 qRT-PCR을 적용하고자 본 연구를 수행하였다. 논 토양 미생물의 gDNA를 분리하기 위하여 Mo Bio kit를 사용한 효과적이고 안정적인 gDNA 분리 방법을 확립하였다. 논 토양 미생물 다양성을 qRT-PCR로 검출하기 위하여 bacteria를 세분한 ${\alpha}$-Proteobacteria, ${\beta}$-Proteobacteria, Actinobacteria, Bacteroidetes, Firmicutes 다섯 가지 문과 전체 bacteria, 전체 fungi를 구분할 수 있는 특이 primer set을 선정하여 다양한 조건의 시험을 통하여 최종 조건을 확립하였으며 재현성 실험을 통하여 방법의 유의성을 검증하였다.

• 한국균학회지
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• 제42권4호
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• pp.269-275
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• 2014

7종의 자생 염생식물은 천일사초, 갯질경, 퉁퉁마디, 나문재, 칠면초, 해홍나물, 그리고 지채로서 태안반도에서 채집되었다. 염생식물의 뿌리로부터 분리된 37균주의 내생진균은 ITS영역 염기서열에 대하여 분석하였다. 모든 내생진균들은 다양성 지수들을 이용하여 분석되었다. 분리된 내생진균은 Eurotiales (78%), Capnodiales (5%), Hypocreales (5%), Agaricales (3%), Corticiales (3%), Glomerellales (3%), Pleosporales (3%)으로 7개 목으로 분류되었다. 그리고 분리된 내생진균의 속을 분석한 결과 자낭균문과 담자균문에 포함되는 Alternaria, Aspergillus, Cladosporium, Paecilomyces, Penicillium, Phanerochaete, Schizophyllum, Talaromyces, Verticillium등 9개 속으로 분류되었다. 내생진균을 분석하였을 때, Penicillium이 염생식물로부터 가장 많이 분포하고 있었다. 본 연구는 태안반도에 자생하는 염생식물들에 대한 내생진균의 분포와 다양성을 분석하였다.

• Mycobiology
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• 제45권4호
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• pp.392-400
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• 2017

Peanut yield and quality are seriously affected by pod rot pathogens worldwide, especially in China in recent years. The goals of this study are to analyze the structure of fungal communities of peanut pod rot in soil in three peanut cultivars and the correlation of pod rot with environmental variables using 454 pyrosequencing. A total of 46,723 internal transcribed spacer high-quality sequences were obtained and grouped into 1,706 operational taxonomic units at the 97% similarity cut-off level. The coverage, rank abundance, and the Chao 1 and Shannon diversity indices of the operational taxonomic units were analyzed. Members of the phylum Ascomycota were dominant, such as Fusarium, Chaetomium, Alternaria, and Sordariomycetes, followed by Basidiomycota. The results of the heatmap and redundancy analysis revealed significant variation in the composition of the fungal community among the three cultivar samples. The environmental conditions in different peanut cultivars may also influence on the structure of the fungal community. The results of this study suggest that the causal agent of peanut pod rot may be more complex, and cultivars and environmental conditions are both important contributors to the community structure of peanut pod rot fungi.