• The Korean Journal of Mycology
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• v.47 no.2
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• pp.121-124
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• 2019

An endophytic fungus, Rhizosphaera pini strain NIE7426, was isolated from the sub-alpine coniferous tree Abies nephrolepis in Mt. Nochu of Gangwon Province. It was characterized by macroscopic and microscopic features, as well as the internal transcribed spacer (ITS) 1, 2 and 5.8S sequences. All morphological and molecular features support the first recognition of this taxon in Korea. In addition, this study adds A. nephrolepis as a host plant R. pini.

• Parasites, Hosts and Diseases
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• v.55 no.1
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• pp.39-45
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• 2017

The present study was performed to reveal the morphological characteristics and molecular phylogenetic position of Platynosomum fastosum Kossack, 1910. A total 167 specimens of P. fastosum were collected in 8 (4.9%) out of 163 sets of gall-bladders and bile ducts of cats. The number of worms was 1-105 per infected cat. This species was characterized by having a long and slender body, slightly larger ventral sucker than the oral sucker, indistinct prepharynx, small pharynx, short esophagus, bifurcation midway between 2 suckers, and ceca extending to the posterior end of the body. The length of the partial sequences of ITS1 and 5.8S rDNA of P. fastosum were 990 bp, GC-rich. AT/GC ratio was 0.9, there were 9 polymorphic sites, and intraspecific variations ranged from 0.1% to 0.9%. Phylogenetic analyses by neighbor-joining phylogram inferred from ITS1 rDNA sequences revealed that the genetic distance between P. fastosum specimens ranged from 0.3 to 1.5% while the smallest interspecific distance among dicrocoeliid species was 20.9 %. The redescription and genetic characters of P. fastosum are taxonomically important to recognize future different species of the genus Platynosomum showing high intraspecific and morphological variability.

• Korean Journal of Plant Taxonomy
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• v.46 no.2
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• pp.129-148
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• 2016

Plant species on oceanic islands comprise nearly 25% of described vascular plants on only 5% of the Earth's land surface yet are among the most rare and endangered plants. Conservation of plant biodiversity on islands poses particular challenges because many species occur in a few and/or small populations, and their habitats on islands are often disturbed by the activity of humans or by natural processes such as landslides and volcanoes. In addition to described species, evidence is accumulating that there are likely significant numbers of "cryptic" species in oceanic archipelagos. Plant systematists, in collaboration with others in the botanical disciplines, are critical to the discovery of the subtle diversity in oceanic island floras. Molecular data will play an ever increasing role in revealing variation in island lineages. However, the input from plant systematists and other organismal biologists will continue to be important in calling attention to morphological and ecological variation in natural populations and in the discovery of "new" populations that can inform sampling for molecular analyses. Conversely, organismal biologists can provide basic information necessary for understanding the biology of the molecular variants, including diagnostic morphological characters, reproductive biology, habitat, etc. Such basic information is important when describing new species and arguing for their protection. Hybridization presents one of the most challenging problems in the conservation of insular plant diversity, with the process having the potential to decrease diversity in several ways including the merging of species into hybrid swarms or conversely hybridization may generate stable novel recombinants that merit recognition as new species. These processes are often operative in recent radiations in which intrinsic barriers to gene flow have not evolved. The knowledge and continued monitoring of plant populations in the dynamic landscapes on oceanic islands are critical to the preservation of their plant diversity.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.566-574
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• 2018

The purpose of this study was to identify the phylogenetic relationships of the plants in the Korean genus Suaeda and to find out the molecular markers that could confirm the interspecies relationships in the family tree through molecular phylogenetic studies. We used the nuclear ribosomal DNA ITS and the chloroplast DNA matK, psbA-trnH, and trnL-trnF as the molecular markers. We could not distinguish between S. japonica and S. maritima and between S. maritima and S. australis in the ITS region and could not distinguish between S. japonica and S. australis with the base sequence in the psbA-trnH and trnL-trnF region. However, we analyzed the combinations of four molecular marker regions and confirmed that each of five plant species of the genus Suaeda formed the independent line. Therefore, it is considered that combinations of molecular markers would be useful for the analysis of phylogenetic relationships in the genus Suaeda. Further investigations of the ecological and morphological characteristics would be needed to understand the phylogenetic relationship and lineage diversification in the genus Suaeda.

• Food Science of Animal Resources
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• v.29 no.4
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• pp.415-422
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• 2009

In this study, several factors were analyzed in an effort to determine the effects of transglutaminase (TGase) treatment on sodium caseinate (NaCN), ${\alpha}--lactalbumin$ (${\alpha}-La$), and ${\beta}-lactoglobulin$ (${\beta}-Lg$) polymerization reactions. The results of SDSPAGE showed that NaCN was slightly hydrolyzed to molecular weights of 50-400 kDa according to activation time. ${\alpha}-La$ formed high-molecular polymers of 30-300 kDa, whereas ${\beta}-Lg$ remained almost completely unhydrolyzed. Melting temperatures of NaCN, ${\alpha}-La$ with and without TGase were all in the range of $100{\pm}10^{\circ}C$ under the endothermic curve, and the melting temperature of ${\beta}-Lg$ with TGase was lower than that with TGase. When the proteins were incubated for 3 h with TGase, the micrographic structures showed a small quantity of sediment and broad layers. The final ${\alpha}-La$ residues remained at a level of 21.38%, and the TGase-treated ${\alpha}-La$ was confirmed to have undergone a profound loss of mass, to 18.25%. The DPPH-radical scavenging activity of NaCN and ${\beta}-Lg$ with TGase treatment was higher than that observed in the untreated sample, while those of ${\alpha}-La$ increased with concentration.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.393-399
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• 2016

This study was conducted to investigate whether the presence of mcy gene and microcystin production are related to morphological characteristics of Korean Microcystis species. We isolated 6 different species of Microcystis (M. aeruginosa, M. ichthyoblabe, M. flos-aquae, M. novacekii, M. viridis and M. wesenbergii) from drinking water supply dams (Yeongchun, Ankei, Gachang), and used microscopic method for morphological identification, molecular method for amplifying a partial region of mcyB gene and ELISA method for microcystin analysis. In the present study, 80% of M. aeruginosa strains contained mcy gene, followed by 45% (10 strains) of M. icthyoblabe, 33% (1 strain) of M. wesenbergii, and 11% (4 strains) of M. flos-aquae. Each percentage of mcy gene in Microcystis morphospecies was similar to that of microcystin production in Microcystis morophospecies. In conclusion, the present study shows that molecular method using mcy gene primers can be used as an indirect indicator for the monitoring of toxic cyanobacteria (Microcystis).

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.1 no.1
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• pp.52-57
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• 2020

Bacterial symbionts are common across insects, including ants (Hymenoptera: Formicidae). Reproduction-manipulating endosymbionts, such as Wolbachia, Spiroplasma, Rickettsia, and Cardinium, are closely associated with many aspects of host-insect life. In addition, phage WO plays an essential role in the phenotypic effects of Wolbachia. Although endosymbionts are possible biological control agents, there is a lack of knowledge of their rate of infection of ants in Korea. We tested a range of Korean ant species for the presence of Wolbachia, Spiroplasma, Rickettsia, Cardinium, and phage WO by extracting DNA from the ants and using specific primer sets to test the status of infections. In addition, the mitochondrial cytochrome c oxidase I (COI) gene of the host ants was amplified to confirm the molecular identification and phylogenetic relationship between the hosts. We found that infection with Wolbachia (29.6% of species) is relatively common when compared with that of other endosymbionts. Only one species was infected with Spiroplasma. Infection with Rickettsia and Cardinium was not detected in the examined ants. Most Wolbachia in ants were infected with phage WO. Although the phenotypic effects of endosymbionts in ants are still unknown, this first survey of endosymbionts in Korea is the first step toward the use of reproduction-manipulating endosymbionts.

• Journal of Ecology and Environment
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• v.37 no.4
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• pp.387-393
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• 2014

We propose Cryptonemia asiatica sp. nov. from Korea and Japan. We used molecular analyses of plastid-encoded rbcL and morphological observations to resolve the taxonomic identities of C. lactuca from Korea, C. luxurians from Japan, and C. seminervis from Spain. Specimens of C. lactuca and C. luxurians fell within the same molecular phylogenetic clade (with 100% bootstrap support) and were clearly separated from specimens of C. luxurians collected from the type locality in Brazil. Our analyses demonstrated identical molecular sequences between C. seminervis specimens from Spain and C. lomation specimens from France. Morphological characteristics of the new species, C. asiatica include prominent midribs through the mid thallus, a cortex 4-6 cells thick, and a blade with undulate margins. Molecular evidence indicates that specimens from Korea and Japan previously assigned to C. lactuca and C. luxurians, respectively, should be reassigned to Cryptonemia asiatica. Binomial C. luxurians from Brazil should be resurrected as the independent species of Cryptonemia.

• The Korean Journal of Ecology
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• v.28 no.2
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• pp.63-67
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• 2005

The eleven local samples of six species including Corbicula leana examined in this study were collected from the Nam River and the Nakdong River in Korea. Buzas's new formula was used to evaluate the ecological biodiversity among eleven populations and six species. In addition, enzyme electrophoresis was used to genetic diversity within and among populations of C. leana. The upper populations of the river have fewer species than the middle and low populations of this river. The genetic diversity trends to increase from the source of the main river to the mouth. It suggests that the population of downstream might be expanded toward upstream.

• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.682-688
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• 2014

The in vitro digestibility and molecular and crystalline structures of rice starches (Seilmi, Dasan1, and Segoami) with differing amylose content were investigated. Segoami had the highest amylose content (30.9%), whereas Dasan1 had the lowest amylose content (21.2%). The molecular weight ($\bar{M}_w$) of amylose and amylopectin in Segoami was much lower than that of the other two rice starches. Segoami had the highest proportion (8.7%) of amylopectin short branch chains (DP 6-12) and the lowest proportion of B1 chains (DP 13-24). The relative crystallinity, intensity ratio of $1047-1022cm^{-1}$ (1047/1022) and gelatinization enthalpy followed the order: Segoami>Seilmi~Dasan1. Segoami showed substantially low pasting viscosity. Rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) contents showed the highest value in Seilmi, Dasan1, and Segoami, respectively. The expected glycemic index (eGI) of Segoami was lower than that of the other two rice starches. Overall results suggested that the digestibility of rice starch could be highly influenced by their molecular and crystalline structure.