• The Korean Journal of Mycology
• /
• v.49 no.3
• /
• pp.393-397
• /
• 2021

The unrecorded fungus Galactomyces pseudocandidus de Hoog & M.T. Sm. was isolated and cultured from an introduced species, Procambarus clarkii, in Korea. Two related species, Galactomyces citri-aurantii and Geotrichum candidum, have been reported, but no other Galactomyces spp. have been found in Korea. In this study, we isolated G. pseudocandidus from the digestive tract of American crayfish using RGY (river water-glucose-yeast) medium and then compared the morphological and molecular characteristics of this species with those of related species. As a result, we confirmed that G. pseudocandidus is an unrecorded fungus in Korea, so we described and reported the cultural characteristics and microstructures, such as conidia.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.55 no.1
• /
• pp.37-50
• /
• 2022

The use of uncertain names for imported crustaceans causes considerable confusion for the establishment of government policies and the public market. Therefore, there have been demands for reestablishment of the domestic names of imported fish to correct the market order and to prevent damage caused by confusion among consumers. A total of 118 species of imported fisheries crustaceans were reviewed (47 crab spp., 36 shrimp spp., 27 lobster and crayfish spp., five mantis shrimp spp., and three horseshoe crab spp.). Although not belonging to the Subphylum Crustacea, three species of the Subphylum Chelicerata and five species of the Order Stomatopoda were included for review. Of these, 49 species that require Korean name assignment and reexamination of domestic names were selected and Korean names were assigned.

• Korean Journal of Environmental Biology
• /
• v.41 no.3
• /
• pp.325-334
• /
• 2023

The invasive red swamp crayfish, Procambarus clarkii, is native to south-central United States and northeastern Mexico. Recently, it has been being spreading in the wild in South Korea. However, its primary sources, introduction routes, establishment, and expansion in South Korea remain unclear. Here, we analyzed genetic diversity and population genetic structures of its domestic natural populations during early invasion, commercial stock from local aquaria (a suspected introduction source), and original United States population using mitochondrial COI gene sequences for 267 individuals and eight microsatellite markers for 158 individuals. Natural and commercial populations of P. clarkii showed reduced genetic diversity (e.g., haplotype diversity and allelic richness). The highest genetic diversity was observed in one original source population based on both genetic markers. Despite a large number of individuals in commercial aquaria, we detected remarkably low genetic diversity and only three haplotypes among 226 individuals, suggesting an inbred population likely originating from a small founder group. Additionally, the low genetic diversity in the natural population indicates a small effective population size during early establishment of P. clarkii in South Korea. Interestingly, genetic differentiation between natural populations and the United States population was lower than that between natural populations and aquarium populations. This suggests that various genetic types from the United States likely have entered different domestic aquariums, leading to distinct natural populations through separate pathways. Results of our study will provide an insight on the level of genetic divergence and population differentiation during the initial stage of invasion of non-indigenous species into new environments.

• Journal of Korean Home Economics Education Association
• /
• v.12 no.2
• /
• pp.47-64
• /
• 2000

The purpose of this study was to search the calcium and iron rich foods in Korean people. The food sources presented in the current home economics textbooks of middle and high school were investigated. And 40 kinds of calcium and iron rich foods were selected by the quantity in 100g edible portion. one serving size and according to 1997 food supply data. Also 3 major food groups of calcium and iron supply in Korean were identified, and 10 rich foods for each food groups were selected. The results were summarized as follows. 1. The food sources of calcium 1) The food sources of calcium presented in the home economics textbooks of middle and high school are milk and dairy products. small fishes such as anchovy icefish and dried strip and green vegetables etc. 2) The calcium rich foods by 100g edible portion were in order of skim milk powder river snail sesame sea mustard. whole milk powder. snapping turtle loach sea tangle(dried) opossum shrimp and sea lettuce(dried). And the calcium rich foods by the calcium content in one serving were in order of river snail snapping turtle opossum shrimp loach spiny lobster skate skim milk powder small alaska pollack freshwater crab condensed milk whole milk powder skate ray and milk. 3) The 3 major calcium supply food groups in Korean were vegetables fish and shellfishes and milk and dairy products. 4) The calcium supply foods according to the quantity of food supply in 1997 was in order of sea mustard, milk anchovy chinese cabbage soybean skin milk powder laver shrimp welsh onion and maize. The vegetables were the important sources of calcium in Korean. 2. The food sources of iron 1) The food sources of iron which are commonly presented in the textbooks of middle and high school were meat liver egg(egg yolk) and green vegetables etc 2) The iron rich foods on the basis of the iron content in 100g edible portion were in order of surf clam marsh clam laver(dried)( sea lettuce(dried), crayfish pelilla seed little neck clam orient hard clam, venus clam, and freshwater carab. And the iron rich foods by the iron content in one serving were in order of surf clam marsh clam crayfish little neck clam orient hard clam freshwater crab venus clam hen cockle green confertii(fresh) pen shell and spiny lobster. 3) The 3 major iron supply food groups in Korean were cereals an cereal products fishes and shellfishes and vegetables. 4) The iron supply food according to the quantity of food supply in 1997 was in order of soybean sea mustard maize rice meat edible viscera laver wheat flour, pook, red pepper, egg and bovine meat.

• The Korean Journal of Zoology
• /
• v.29 no.1
• /
• pp.23-30
• /
• 1986

Animals in Order Decapoda consist of a plentiful species and vary in external and internal shape, taste, feeding habit and the feature of alimentary canal. In this case, the morphological study on the midgut epithelium of filter feeding Decapoda in Crustacea, Korean fresh water crayfish (Cambaroides similis Koelbel), the only species dwelling in Korea, were performed by scanning electron microscopy. The anterior-most parts of midgut epithelium appeared to be many shallow, dense and irregular folds where a linear microvilli (MV) (1-3$\\mu$m long) numbered from a few to ten had raised. Middle part of the gut, the folds got gradually shallower. MV arranging on one, two or three lines were slightly thicker than those mentioned above. The number of MV in each group seemed gradual decrease from a apical border with maximum thirty in group to furrow with none. From the middle to posterior parts of the gut, the MV were slightly thinner and longer (2.5-4 $\\mu$m long) and raised twelve on a line and, in some cases, added from one to five on another line. On the posterior-end parts of the gut, the epithelium showed many shallow and dense folds as the anterior parts again. A group of thin and long MV (2-7 $\\mu$m long) countable fifteen on a line were raised to the base of each fold. In some cases, the MV also added utmost in five on the other line. All the MV observed in this study were posteriorly directed.

• Journal of Ecology and Environment
• /
• v.47 no.4
• /
• pp.200-210
• /
• 2023

Background: Cambaroides similis is an endangered candidate species living in the stream of South Korea. Freshwater crayfish is known to decline rapidly not only domestically, but also internationally. Its decline is projected to be further exacerbated due to climate change. Understanding physical characteristics of the habitat is crucial for the conservation of an organism. However, comprehensive data regarding the distribution and physical habitat characteristics of C. similis are currently unavailable in South Korea. Thus, the objective of this study was to ascertain preferred ranges for water depth, current velocity, and streambed substrate of C. similis using Weibull model. Results: In this study, C. similis was found at 59 sites across 12 regions in South Korea. Its optimal water depth preferences ranged from 11.9 cm to 30.1 cm. Its current velocity preferences ranged from 9.8 cm s^-1 to 29.1 cm s^-1. Its substrate preferences ranged from -5.1 𝜱_m to -2.5 𝜱_m. Median values of central tendency were determined as follows: water depth of 21.4 cm, current velocity of 21.2 cm s^-1, and substrate of -4.1 𝜱_m. Mean values of central tendency were determined as follows: water depth of 21.8 cm, current velocity of 22.0 cm s^-1, and substrate of -4.4 𝜱_m. Mode values of central tendency were determined as follows: water depth of 21.7 cm, current velocity of 20.1 cm s^-1, and substrate of -3.7 𝜱_m. Conclusions: Based on habitat suitability analysis, physical microhabitat characteristics of C. similis within a stream were identified as Run section with coarse particle substrate, low water depth, and slow current velocity. Due to high sensitivity of these habitats to environmental changes, prioritized selection and assessment of threats should be carried out as a primary step.

• The Korean Journal of Soil Zoology
• /
• v.8 no.1_2
• /
• pp.7-12
• /
• 2003

Endogeneous endoglucanase (EC 3.2.1.4) cDNA was cloned from a representative species (Eisenia anderi) of the earthworm family Lumbricidae. Endoglucanase from the midgut of the earthworm is composed of 456 amino acids and belongs to glycosyl hydrolase family 9 (GHF9), sharing high homologies (50-51 %) with those of selected termite and crayfish. This endoglucanase consists of three consensus catalytic domains found in most microbial cellulases. A phylogenetic tree was constructed using the amino acid squence data matched through the BLASTX program and showed that GHF9 families could be divided into four groups of arthropoda, bacteria, plant and annelida.

• Journal of Yeungnam Medical Science
• /
• v.27 no.1
• /
• pp.69-73
• /
• 2010

A paragonimiasis infestation is caused by the paragonimus species. Paragonimiasis mainly occurs by ingestion of raw or undercooked freshwater crabs or crayfish. In our country, the prevalence of paragonimiasis was high until late 1960s due to eating habits, but after the 1970s the prevalence of the disease has markedly decreased and now the disease is rarely seen. The diagnosis of tuberculosis by Chest X-ray is often confused with pulmonary carcinoma, bacillary and parasitic infections, and chronic mycosis. Pulmonary paragonimiasis must be considered in the differential diagnosis of lung cancer especially in the appropriate clinical setting because effective treatment with praziquantel can be rewarding. We report a case of a 58-year-old woman with pulmonary paragonimiasis that was suspicious for lung cancer, as detected by biopsy.

• Journal of Life Science
• /
• v.10 no.2
• /
• pp.218-227
• /
• 2000

Bone morphogenetic protein 1 (BMP-1) is part of a complex capable of inducing ectopic bone formation in mammals. Studies on TGF-β1 processing and Drosophila dorsal-ventral patterning have focused attention on BMP-1 as important in mediating the biological activity of this bone inducing complex. Herein, the bacterial expression, refolding, purification, and initial characterization of the BMP-1 proteolytic domain (BPD) are described. A semi-quantitative fluorescence-based thin layer chromatography assay was developed to assist in rapidly screening for optimal renaturation conditions. According to a preliminary screen for optimal conditions for the refolding of BPD , a detectable proteolytic activity against a high turnover substrate for astacin, a homologous protease from crayfish was observed. The conditions identified have allowed the expression of sufficient amounts of BPD for the characterization of the protein. Its proteolytic activity exhibits the same cleavage specificity as astacin against seven substrates that were previously synthesized for studying astacin. Furthermore, this activity is inhibited by the metal chelator 1,10-phenanthroline but not by its analogue 1,7-phenanthroline. The collagenase inhibitor Pro-Leu-Gly hydroxamate was found to inhibit both astacin and BPD activity. The results presented in this paper argue that BMP-1 does in fact possess an intrinsic proteolytic activity.

• Parasites, Hosts and Diseases
• /
• v.38 no.3
• /
• pp.167-171
• /
• 2000

We report a chronic cerebral paragonimiasis from a 41-year-old Korean man who complains a headache and weakness of left motor neuron components. Magnetic resonance images of the brain revealed conglomerates of multiple ring-like enhancements in tempore-occipital and frontal lobes of the right hemisphere. An intradermal test for paragonimiasis westermani was positive. The patient was born near an endemic area of paragonimiasis and used to eat boiled or grilled freshwater crayfish in his childhood. Nodules in the brain were resected through craniotomies. The eggs of P. westemani were identified pathologically and parasitologically in the calcified necrotic lesions. Examinations on sputum and fecal specimens for the eggs of P. westemani were shown to be negative and a chest radiograph was normal. It is presumed that the brain lesions were formed by P. westemani approximately 30 years ago.