• Journal of the Korean Wood Science and Technology
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• 제22권3호
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• pp.39-44
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• 1994

This study was carried out to investigate features pertaining to spiral thickenings, which was considered one of the most important diagnostic values, for wood identification. Species, kind of cells with spiral thickening, and ridge numbers of spiral thickening per axial mm were recorded in 71 families, 144 genera, 316 species of Korean hardwoods. Spiral thickening was observed in 128 of 316 species, about 40.5 % of all the investigated, and classified into 6 types on the basis of distributional patterns and morphological features as follows: 1. Type 1, present throughout all vessel element, which was found in 14 families, 19 genera, 43 species. 2. Type 2, present only in small vessel element, which was found in 18 families, 29 genera, 41 species. 3. Type 3, present both in small vessel element and wood fibers, which was found in 8 families, 17 genera, 29 species. 4. Type 4, present in wood fibers, which was found in 1 family, 1 genus, 1 species. 5. Type 5, present only in tail of vessel element, which was found in 4 families, 5 genera, 9 species. 6. Type 6, being present in vessel element faintly or partially, which was found in 2 families, 3 genera, 5 species.

• 한국어류학회지
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• 제7권1호
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• pp.8-11
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• 1995

1986년(年) 5월(月) 제주도(濟州道)에서 채집(採集)한 통구멍과(科) 어류 중 체장(體長) 242.2 mm 되는 1개체(個體)를 동정한 결과(結果) 지금까지 우리나라에서는 서식(棲息)이 확인(確認)되지 않은 미기록종(未記錄種)인 Ichthyscopus lebeck sannio으로 동정(同定)되었다. 본 종은 외부(外部) 형태적(形態的)으로 등지느러미가 1개이고 입술에는 돌기가 발달되어 있고, 체표면에는 커다란 하얀 반점(斑點)이 많이 있으며 쇄골돌기가 없는 점 등이 본종(本種)의 주요(主要) 특징(特徵)으로 나타나고 있다. 본 종의 한국명(韓國名)은 체표면에 흰무늬가 크게 나 있는 것이 눈에 잘 띠기 때문에 "큰무늬통구멍속(屬)"의 "큰무늬통구멍"이라고 명명(命名)하였다.

• 식물분류학회지
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• 제39권3호
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• pp.135-142
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• 2009

엽록체 rbcL gene의 염기서열과 포자의 형태를 바탕으로 고사리삼과 식물의 계통과 제주고사리삼속의 계통학적 위치를 추정하였다. 엽록체 DNA rbcL 염기서열의 분석 결과 고사리삼과는 뚜렷하게 고사리삼계보 (Botrychioid lineage)와 나도고사리삼계보 (Ophioglossoid lineage)의 두 군으로 구분되었다. 고사리삼계보에 있어 제주고사리삼속(Mankyua)은 Helmintostachys속과 함께 분계의 기저에서 고사리삼속(Botrychium)의 자매분류군으로 분지하였으나, 이들 고사리삼속(Botrychium), 제주고사리삼속(Mankyua), 및 Helmintostachys속 사이의 계통적 유연관계는 결정되지 못했다. 고사리삼속의 경우 Sceptridium아속과 Botrychium아속이 뚜렷한 단계통을 형성하였으나, Botrypus아속에 속한 분류군들은 고사리삼속의 기저에서 다른 고사리삼속 분류군의 자매분류군으로 분지하면서 단계통이 아닌 것으로 밝혀졌다. 나도고사리삼계보를 형성하는 나도고사리삼속(Ophioglossum)의 경우, Ophioglossum아속은 단계통을 형성하였으며, Ophioglossum아속에 대해 Cheiroglossa아속 및 Ophioderma 아속이 차례로 자매분류군으로 분지하였다. 염기서열 계통수, 포자의 형태 및 외부형태의 고찰에 있어 제주고사리삼속은 Helminthostachys와 유사하지만, 계통수에서 patristic distance 뿐 아니라 포자소엽의 형태가 뚜렷이 구분되어 이들 2속은 독립된 속으로 판단된다.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3681-3689
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• 2013

This study explored a direct SET-photochemical strategy to construct a new family of thioene conjugated-naphthalamide fluorophore based lariat-crown ethers which show strong binding properties towards heavy metal ions. Irradiations of designed nitrogen branched (trimethylsilyl)methylthio-terminated polyethylenoxy-tethered naphthalimides in acidic methanol solutions have led to highly efficient photocyclization reactions to generate naphthalamide based lariat type thiadiazacrown ethers directly in chemo- and regio-selective manners which undergo very facile secondary dehydration reactions during separation processes to produce their corresponding amidoenethio ether cyclic products tethered with electron donating diethyleneoxy- and diethyenethio-side arm chains. Fluorescence and metal cation binding properties of the lariat type enamidothio products were examined. The photocyclized amidoenethio products, thioene conjugated naphthalamide fluorophore containing lariat-thiadiazacrowns exhibited strong fluorescence emissions in region of 330-450 nm along with intramolecular exciplex emissions in region of 450-560 nm with their maxima at 508 nm. Divalent cation $Hg^{2+}$ and $Pb^{2+}$ showed strong binding to sulfur atom(s) in side arm chain and atoms in enethiadiazacrown ether rings which led to significant enhancement of fluorescence from its chromophore singlet excited state and concomitant quenching of exciplex emission. The dual fluorescence emission responses towards divalent cations might provide a new guide for design and development of fluorescence sensors for detecting those metals.

• Journal of Microbiology and Biotechnology
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• 제22권12호
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• pp.1724-1730
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• 2012

An ${\alpha}$-L-arabinofuranosidase (TmAFase) from Thermotoga maritima MSB8 is a highly thermostable exo-acting hemicellulase that exhibits a relatively higher activity towards arabinan and arabinoxylan, compared with other glycoside hydrolase 51 family enzymes. In the present study, we carried out the enzymatic characterization and structural analysis of TmAFase. Tight domain associations found in TmAFase, such as an inter-domain disulfide bond (Cys306 and Cys476) in each monomer, a novel extended arm (amino acids 374-385) at the dimer interface, and total 12 salt bridges in the hexamer, may account for the thermostability of the enzyme. One of the xylan binding determinants (Trp96) was identified in the active site, and a region of amino acids (374-385) protrudes out forming an obvious wall at the substrate-binding groove to generate a cavity. The altered cavity shape with a strong negative electrostatic distribution is likely related to the unique substrate preference of TmAFase towards branched polymeric substrates.

• Mycobiology
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• 제45권4호
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• pp.255-262
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• 2017

A total of 121 species of lichens belonging to the genus Arthothelium have been described to date, most of which have been found in tropical regions. Here, we describe the discovery of a novel Arthothelium species for the first time in South Korea. Until now, Arthothelium ruanum was the only Arthothelium species reported in South Korea. Among the 113 specimens collected in this study, we identified A. ruanum and a putative new species, Arthothelium punctatum (J. S. Park & J.-S. Hur, sp. nov.). The diagnostic characters of A. punctatum are as follows: apothecia punctate, shortly elongate to branched, small, 0.1-0.2 mm wide, hypothecium hyaline to pale brown and obovate to broadly ellipsoid, muriform ascospores, $29.5-44.6{\times}12.2-18.2{\mu}m$. The new species was found in Mt. Seokbyeong at an altitude of 790 m on smooth bark. Upon phylogenic analysis, the putative new species, A. punctatum, was separated from other Arthothelium species although the specimens analyzed were clustered with Arthoniaceae in phylogenetic trees based on both the mitochondrial small subunit (mtSSU) sequence and combined mtSSU and nuclear ribosomal large subunit sequences. Our data clearly indicate that this species is a new species belonging to the family Arthoniaceae. To elucidate the taxonomic characteristics of the new species, we provide morphological descriptions and a distribution map.

• 한국균학회지
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• 제49권1호
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• pp.45-55
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• 2021

본 연구에서는 A. microsporus의 최적 배양 조건을 구명하고자 하였다. A. microsporus 균사체의 효율적 배양을 위한 조건은 최적 배양 온도 25℃, pH 5.0, 탄소원 soluble starch 1%, 유기질소원 malt extract 1%, 무기질소원 NH₄H₂PO₄ 0.1%, 아미노산 asparatic acid 0.1% 조건으로 선발되었고 유기산, 무기염류 첨가 시 균사생육이 저조해지는 영향을 주어 선발되지 않았다. 새로이 SMNA로 명명한 A. microsporus의 최적 배지는 기존의 PDA 배지 상에서 배양한 결과와 비교하였을 때, 균사의 생육이 균일하고 안정적이며 배양 기간을 15.1% 정도 단축하는 효과가 있었다. SMNA 배지는 추후 A. microsporus의 균사체 배양 방법에 널리 활용될 수 있을 것으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제31권2호
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• pp.272-279
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• 2021

Two genes encoding probable α-ʟ-arabinofuranosidase (E.C. 3.2.1.55) isozymes (ABFs) with 92.3% amino acid sequence identity, ABF51A and ABF51B, were found from chromosomes 3 and 5 of Saccharomycopsis fibuligera KJJ81, an amylolytic yeast isolated from Korean wheat-based nuruk, respectively. Each open reading frame consists of 1,551 nucleotides and encodes a protein of 517 amino acids with the molecular mass of approximately 59 kDa. These isozymes share approximately 49% amino acid sequence identity with eukaryotic ABFs from filamentous fungi. The corresponding genes were cloned, functionally expressed, and purified from Escherichia coli. SfABF51A and SfABF51B showed the highest activities on p-nitrophenyl arabinofuranoside at 40~45℃ and pH 7.0 in sodium phosphate buffer and at 50℃ and pH 6.0 in sodium acetate buffer, respectively. These exoacting enzymes belonging to the glycoside hydrolase (GH) family 51 could hydrolyze arabinoxylo-oligosaccharides (AXOS) and arabino-oligosaccharides (AOS) to produce only ʟ-arabinose, whereas they could hardly degrade any polymeric substrates including arabinans and arabinoxylans. The detailed product analyses revealed that both SfABF51 isozymes can catalyze the versatile hydrolysis of α-(1,2)- and α-(1,3)-ʟ-arabinofuranosidic linkages of AXOS, and α-(1,2)-, α-(1,3)-, and α-(1,5)-linkages of linear and branched AOS. On the contrary, they have much lower activity against the α-(1,2)- and α-(1,3)-double-substituted substrates than the single-substituted ones. These hydrolases could potentially play important roles in the degradation and utilization of hemicellulosic biomass by S. fibuligera.

• ALGAE
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• 제39권2호
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• pp.97-108
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• 2024

The Ralfsiaceae family, part of the Ralfsiales order and consisting of crustose brown algae, includes five genera: Analipus, Endoplura, Fissipedicella, Heteroralfsia, and Ralfsia. In this study, a novel crustose genus named Ramipedicella gen. nov. is introduced within the Ralfsiaceae based on molecular and morphological analyses. Phylogenetic analyses using both concatenated dataset (rbcL + COI-5P genes) and rbcL indicate that the crustose brown algae that we collected from Korea and Russia form a unique grouping within the Ralfsiaceae. This grouping is strongly supported by both bootstrap analysis and Bayesian posterior probabilities. The genetic differences in the rbcL and COI-5P sequences between Ramipedicella and other genera within Ralfsiaceae range from 6.7 to 9.3% for rbcL and from 15.5 to 20.8% for COI-5P. Ramipedicella is characterized by crustose thalli having new crusts growing on top of old ones with a hypothallial basal layer and erect perithallial filaments, long cells with width-to-length ratio of 1 : 1-16, single chloroplast per cell, plurangia with one to several sterile cells, one to several unangia produced from unicellular stalks or from the lateral-basal region to the paraphyses, and unangia arising sequencially in irregularly branched specialized filaments. Ramipedicella, the recently identified genus, comprises two distinct species. Ramipedicella miniloba, the type species, is distinguished by crusts with small lobes, numerous hair tufts, plurangia terminated by 1-4 sterile cells, and large oblong unangia. Ramipedicella longicellularis is identified by generally smooth crusts, absence of phaeophycean hairs, plurangia terminated by 1-2 apical sterile cells, and smaller mostly oblanceolate unangia.

• 한국식품영양과학회지
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• 제39권1호
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• pp.54-63
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• 2010

Flavonoid 계열의 한 종류인 baicalin은 항염증, 항암, 항바이러스, 항세균 등의 효능을 가진다. 본 연구진은 선행연구를 통한 이전의 보고에서 baiclain이 adipogenesis pathway(지방세포 형성 경로)의 anti-adipogenic(지방세포 형성억제)과 pro-adipogenic(지방세포 형성 유도) factor들을 조절함으로써 비만 및 adipogenesis를 억제함을 밝혔다. 본 연구에서는, microarray 기술을 이용하여 3T3-L1 세포에서 baiclain이 유도하는 지방세포 형성 억제 효과에 대한 분자적 기작을 보다 상세하게 연구하고자 하였다. 지방세포의 분화 시간(0일, 2일, 4일 및 7일)과 분화 시 baicalin의 처리 유무에 따라 유전자 발현 양상을 분석하기 위해 해당 시료들을 microarray에 적용하였다. Microarray 결과로부터 2배이상의 변화가 있는 3972개의 유전자를 확보하였다. 그 유전자들의 발현 양상을 좀 더 자세히 살펴보기 위해 hierarchical clustering 분석을 진행하였고 그 결과로 20개의 cluster를 분류할 수 있었다. 그들 중 4개의 cluster는 분화의 전반적인 기간에서 baicalin의 첨가에 의해 뚜렷하게 상승(cluster 8과 cluster 10)하거나 반대로 뚜렷하게 감소(cluster 12와 cluster 14)하는 양상을 보였다. Cluster 8과 cluster 10에는 CHOP(CCAAT/enhancer-binding protein homologous protein), INSIG1(insulin induced gene 1), WISP2(WNT1 inducible signaling pathway protein 2), ADM(adrenomedullin), CCND2(cyclin D2), GRN(granulin) 및 TGFB3(transforming growth factor, beta 3)과 같은 세포 증식과 지방세포 형성 억제를 상승시키는 유전자들이 다수 포함되었다. 반대로 cluster 12와 cluster 14에는 세포 증식 억제, 세포 주기 억제 및 세포 성장 억제와 연관되거나 지방세포를 유도하는 유전자인 LTA(lympotoxin A), ACADSB(acyl-Coenzyme A dehydrogenase, short/branched chain), HMGCS2(3-hydroxy-3-methylglutaryl-Coenzyme A synthase 2), IGFBP7(insulin-like growth factor binding protein 7), MERTK(c-merproto-oncogene tyrosine kinase), RASSF2(ras association(RalGDS/AF-6) domain family 2), RHOU(ras homolog gene family, member U) 및 SESN1(sestrin1) 등이 포함되었다. 결론적으로 baicalin은 세포 증식 및 지방세포 형성과 연관된 유전자들을 조절함으로써 지방세포의 분화를 억제하는 것으로 사료된다. 이러한 결과는 baicalin이 유도하는 지방세포 형성 억제 및 비만 억제 효과의 분자적 기작에 대한 중요한 정보를 제시한다.