• 폴리머
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• 제39권3호
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• pp.388-393
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• 2015

PC와 SAN 사이의 계면장력 및 친화도에 미치는 저분자량 성분의 영향을 알아보기 위하여 용매 추출법으로 각 고분자에서 저분자량 성분을 추출하였다. GPC(gel permeation chromatography)로 분자량 분포를 확인한 결과, 각 고분자의 저분자량 성분은 용매 추출법에 의해 효과적으로 제거된 것을 확인하였다. 저분자량 성분이 제거된 고분자를 이용하여 계면장력 및 형태학 분석 결과, 저분자량 성분이 제거된 PC와 SAN은 계면장력이 높아졌고 친화도가 떨어진 것을 확인할 수 있었다. 즉 저분자량 성분이 두 고분자 사이에 상용화제와 같은 역할을 하는 것을 알 수 있었다. 두 고분자 중 SAN의 저분자량 성분이 PC의 저분자량 성분보다 상용화 효과에 더 많이 기여하는 것을 확인하였고, 이로서 PC/ABS 제조 시 저분자량 성분이 많이 포함된 SAN을 사용하는 것이 더 유리하다는 것을 알 수 있었다.

• Mycobiology
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• 제32권3호
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• pp.123-127
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• 2004

Sweet persimmons have been increasingly cultivated in the southern part of Korea. However, anthracnose disease caused by Colletotrichum species is one of the major hindrances in cultivation and productions. In this study, we used polymerase chain reaction(PCR) to detect Colletotrichum species with the AFLP(amplified fragment length polymorphism) method. In AFLP, we used E3(5'-GACTGCGTACCAATTCTA-3') and M1(5'-GATGAGTCCTGAGTAACAG-3') primer combination and, as a result, 262 bp segment was observed in Colletotrichum species only. Specific PCR primers were designed from the sequence data and used to detect the presence of the fungus in genomic DNA isolated from symptomless sweet persimmon plants. Based on sequence data for specific segments, Co.B1(5'-GAGAGAGTAGAATTGCGCTG-3') and Co.B2(5'-CTACCATTCTTCTA GGTGGG-3') were designed to detect Colletotrichum species. The 220 bp segment was observed in Colletotrichum species only, but not in other fungal and bacterial isolates.

• Asian-Australasian Journal of Animal Sciences
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• 제22권10호
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• pp.1441-1446
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• 2009

Composition of intramuscular lipids, phospholipid classes and phospholipid molecular species in traditional Chinese duck meat products was investigated. Free fatty acids and phospholipids were identified and quantified by gas and high performance liquid chromatography, and phospholipid molecular species were determined by mass spectrometry. The results showed that raw duck meat had high quantities of phosphatidylethanolamine and phosphatidylcholine. The percentages of phospholipid classes decreased during three kinds of processing of duck meat products. A selective degradation of phospholipid molecular species with polyunsaturated fatty acids was found in dry-cured duck, but was not found in roasted and water-boiled duck products.

• Journal of Species Research
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• 제11권1호
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• pp.1-9
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• 2022

The phylum Actinobacteria includes many groups of aerobic, Gram-stain-positive, rod, or filamentous shaped bacteria. Actinobacteria are known for multicellular differentiation in some groups, and also for production of various secondary metabolites such as antibiotics. During a series of extensive surveys of indigenous prokaryotic species diversity in Korea, bacterial strains belonging to Actinobacteria were isolated from various sources of terrestrial environments. A total of 21 bacterial strains, belonging to 10 genera in 8 families, were isolated as unrecorded species in Korea. Among them, 11 were assigned to the family Streptomycetaceae, two species assigned to each of the families Microbacteriaceae, Mycobacteriaceae and Nocardioidaceae, and one species assigned to each of the families Euzebyaceae, Corynebacteriaceae, Micrococcaceae and Intrasporangiaceae. At the genus level, Streptomyces (10 species) was the most abundant, followed by Microbacterium and Mycolicibacterium(2 species each), and one species in each of the genera Corynebacterium, Euzebya, Arthrobacter, Terracoccus, Kribbella, Nocardioides and Yinghuangia. The detailed descriptions of each unrecorded species are provided.

• Parasites, Hosts and Diseases
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• 제48권3호
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• pp.231-236
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• 2010

Anopheles fluviatilis James (Oiptera: Culicidae) is one of the known malaria vectors in south and southeastern Iran. Earlier ITS2 sequences analysis of specimens from Iran demonstrated only a single genotype that was identical to species Y in India, which is also the same as species T. We identified 2 haplotypes in the An. fluviatilis populations of Iran based on differences in nucleotide sequences of D3 domain of the 28S locus of ribosomal DNA (rDNA). Comparison of sequence data from 44 Iranian specimens with those publicly available in the Genbank database showed that all of the 288-D3 sequences from Kazeroun and Khesht regions in Fars Province were identical to the database entry representing species U in India. In other regions, all the individuals showed heterozygosity at the single nucleotide position, which identifies species U and T. It is argued that the 2 species may co-occur in some regions and hybridize; however, the heterozygosity in the 288-D3 locus was not reflected in ITS2 sequences and this locus for all individuals was identical to species T. This study shows that in a newly diverged species, like members of An. fluviatilis complex, a single molecular marker may not be sufficiently discriminatory to identify all the taxa over a vast geographical area. In addition, other molecular markers may provide more reliable information for species discrimination.

• Journal of Species Research
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• 제7권1호
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• pp.24-35
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• 2018

During a series of extensive surveys of prokaryotic species diversity in Korea, bacterial strains belonging to Gammaproteobacteria were isolated from various sources of aquatic and terrestrial environments. A total of 39 isolates were obtained, which represented 39 unrecorded species in Korea belonging to 20 genera in 12 families. Enterobacteriaceae was the largest family, as eight species were assigned, which was followed by Moraxellaceae (6 species) and Pseudomonadaceae (5 species). At the genus level, Marinobacter (6 species), and Pseudomonas (5 species) were the main genera, and at least two species were obtained for Acinetobacter (3 species), Psychrobacter (3 species), Shewanella (2 species), Dickeya (2 species), Salinivibrio (2 species), Vibrio (2 species) and Rhodanobacter(2 species). The detailed description of each unrecorded species is provided.

• Animal Systematics, Evolution and Diversity
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• 제28권1호
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• pp.36-41
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• 2012

The larvae of Chaoborus are widely distributed in lakes, ponds, and reservoirs. These omnivorous Chaoborus larvae are crucial predators and play a role in structuring zooplankton communities, especially for small-sized prey. Larvae of Chaoborus are commonly known to produce predator-induced polyphenism in Daphnia sp. Nevertheless, their taxonomy and molecular phylogeny are very poorly understood. As a fundamental study for understanding the role of Chaoborus in predator-prey interactions in a freshwater ecosystem, the molecular identification and phylogenetic relationship of Chaoborus were analyzed in this study. A molecular comparison based on partial mitochondrial cytochrome oxidase I (COI) between species in Chaoborus was carried out for the identification of Chaoborus larvae collected from 2 localities in Korea. According to the results, the Chaoborus species examined here was identified as C. flavicans, which is a lake-dwelling species. Furthermore, partial mitochondrial genome including COI, COII, ATP6, ATP8, COIII, and ND3 were also newly sequenced from the species and concatenated 5 gene sequences excluding ATP8 with another 9 dipteran species were compared to examine phylogenetic relationships of C. flavicans. The results suggested that Chaoborus was more related to the Ceratopogonidae than to the Culicidae. Further analysis based on complete mitochondrial DNA sequences and nuclear gene sequences will provide a more robust validation of the phylogenetic relationships of Chaoborus within dipteran lineages.

• ALGAE
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• 제33권1호
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• pp.37-48
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• 2018

Alaria is the second largest genus of the Laminariales, which is distributed far into the northern Pacific and Atlantic oceans. Due to its high morphological plasticity, over 100 specific and sub-specific names have been used in Alaria, this has been tailored down to the present 17 species through morphological revision and molecular phylogenetic analysis. Endemic species of Alaria from Russian Far East have not been thoroughly revised since their original description, and few of them were confirmed using molecular data until recently. We carried out morphological and molecular studies on A. paradisea which is an endemic species distributed on the Kurile Islands, first described by Miyabe and Nagai in 1932 as Pleuropterum paradiseum. The range of morphological variability and its distribution was re-evaluated using the type specimen as well as other specimens. Analyses of partial mitochondrial cytochrome c oxidase subunit 1 and nuclear-encoded internal transcribed spacer sequences showed that A. paradisea nested within the genus Alaria, but differs morphologically from any other Alaria species in having additional sporophylls with a central midrib (${\beta}-sporophylls$). Our results showed that A. paradisea clearly belongs to the genus Alaria based on DNA data, although the key morphological character that was used to include this species to the genus Pleuropterum, ${\beta}-sporophylls$, is stable and distinguishes it from other Alaria species.

• 한국식품과학회지
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• 제19권4호
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• pp.377-381
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• 1987

수박씨기름의 triglyceride에서 산정(算定)가능한 분자종(分子種)은 26종류였으며 주요분자종(主要分子種)은 $C_{18:1}{\cdot}C_{18:2}{\cdot}C_{18:1}$ OLO 6.4%, $C_{18:0}{\cdot}C_{18:2}{\cdot}C_{18:2}$ SLL 7.1%, $C_{18:1}{\cdot}C_{18:2}{\cdot}C_{18:2}$ OLL 16.6%, $C_{16:0}{\cdot}C_{18:2}{\cdot}C_{18:2}$ PLL 19.6% 및 $C_{18:2}{\cdot}C_{18:2}{\cdot}C_{18:2}$ LLL 27.6%의 5종류였으며, 77.3%를 차지하였다.

• 한국식품영양과학회지
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• 제16권4호
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• pp.337-342
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• 1987

Triglyceride 조성(組成)과 췌장리파제에 의한 PN별(別) 획분(劃分)의 ${\beta}$위치(位置)의 지방산조성(脂肪酸組成)의 결과로부터, 산정가능(算定可能)한 홍화유의 triglyceride 분자종은 23종류였다. 10% 이상을 차지하는 triglyceride분자종은 $C_{18:1}\;C_{18:2}\;C_{18:2}\;OLL;\;13.5%,\;C_{16:0}\;C_{18:2}\;C_{18:2}\;PLL;\;15.0%,\;C_{18:2}\;C_{18:2}\;C_{18:2}\;LLL;\;50.6%$로서 전체의 79.1%이었다.