• Applied Biological Chemistry
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• v.50 no.2
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• pp.101-106
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• 2007

Twenty-two strains of nematophagous fungi were isolated from 100 soil samples. Nematophagous fungi were classified into three categories; 3-dimensional adhesive nets (A group), 2-dimensional adhesive nets (B group) and constricting ring (C group). Nine strains were selected and identified on the basis of morphological characteristics (hypha, conidiophore, form and size of conidia, number of conidia, node of conidophore, number and location of septa, size and color of chlamydospore) and ITS (internal transcribed spacer) region of rDNA sequences. As the results, the isolated were identified as belonging to the species of Monacrosporium thaumasium (Kan-2, Kan-4, Kan-11), Arthrobotrys oligospora (Kan-9, Kan-13, Kan-20, Kan-21), A. musiformis (Kan-12), and A. dactyloides (Kan-22).

• Research in Plant Disease
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• v.25 no.3
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• pp.149-155
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• 2019

Nematode-trapping fungi develop trap and consume nematodes are an important part of the subsoil ecosystem and they share a special predator-prey relationship. Four nematode-trapping species, there with adhesive network, Arthrobotrys oligospora, A. sinensis, A. thaumasia and one with constricting ring, Drechslerella brochopaga were collected from soils in Korea and tested their predacity against 12 different nematode species. They were three feeding groups, plant-parasitic (Meloidogyne incognita and Pratylenchus penetrans), fungivorous (Aphelenchus avenae), bacteriovorous (Betlerius sp. and Diplogasteritus sp. in diplogasterid, Panagrolaimus labiatus, P. multidentatus in panagrolaimid, Mesorhabditis irregularis, Pelodera strongyloides and Rhabditis sp., in rhabditid, and Acrobeloides sp. in cephalobid). Results showed that nematode-trapping fungi successfully captured most of nematodes in Petri dish in the group of plant-parasitic nematodes and rhabditids, moderately and variably in other nematodes in 15 days. But it didn't captured A. avenae and Acrobeloides sp. both belongs to c-p group 2. Numbers of Acrobeloides sp. and A. avenae even increased during the test period. The results of this study indicated that nematode-trapping fungi may have specificity among nematode species.

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.291-301
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• 2019

Nematophagous fungi can capture, kill, and digest nematodes using a specific capturing organ. Of the nematophagous fungi, while Arthrobotrys flagrans and A. superba have been described previously, certain characteristics have not been described. For a detailed description of the two nematophagous fungi, the fungi were isolated from soil samples and produced in a pure culture. Morphological characteristics, such as predatory ability (according to the nematode species), shape, and size of predatory organ, conidia, and chlamydospore were investigated and they were used for identification of the fungal isolates along with molecular phylogenetic analysis. Furthermore, this study provides the classification key for 21 nematophagous species.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.1
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• pp.95-101
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• 2018

The epidermis which is stratified by epithelial tissue renewal based on keratinocyte differentiation protects the organism from various environmental insults by forming a physical barrier. Autophagy is a mechanism which mediates lysosomal delivery and degradation of protein aggregates, damaged organelles and intracellular microorganisms. Recent reports have shown that autophagy has critical roles for proper terminal differentiation to stratum corneum via removing metabolic organelles and nuclei. However, whether increasing autophagy can activate epidermal differentiation is unknown. Here, we screened a library of natural single compounds and discovered that betaine specifically increased the LC3 positive cytosolic punctate vesicles and LC3-I to LC3-II conversion in HaCaT human keratinocyte cell line, indicating increased autophagy flux. mTOR pathway, which negatively regulates autophagy, was not affected by betaine treatment, suggesting betaine-induced autophagy through an mTOR-independent pathway. Betaine-induced autophagy was also observed in primary human keratinocyte and skin equivalent. Furthermore, epidermal thickness was increased in skin equivalent under betaine treatment. Overall, our finding suggests that betaine as a novel regulator of autophagy may induce epidermal turnover and improve the skin barrier abnormality of the aged epidermis.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.22-22
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• 2003

로티퍼는 해산어와 담수어뿐만 아니라 식용어와 관상어에 이르기까지 모든 어류의 인공 종묘 생산 과정에서 초기 먹이생물로 이용되고 있는 중요한 동물 플랑크톤이다. 그리고 로티퍼를 초기 자어의 첫 먹이로 사용하는 것을 시작으로 알테미아, 코페포다 또는 초미립자 사료 등을 사용하는 어류 인공종묘 생산 과정에서의 먹이계열이 확립되어 있다. 그러나, 사육하고자 하는 어종에 따라 초기 자어기에서 로티퍼를 섭이하는 시기와 사육 일령별 자어의 로티퍼 포식수를 알 수 있는 정확한 방법이 없다는 이유로 지금까지는 자어의 로티퍼 최초 포식 일령 및 로티퍼 포식수를 개개의 연구자들 나름대로의 방법으로 관찰하여 왔다. 일반적으로 자어가 로티퍼를 포식하였는지의 여부 및 포식수는 자어 소화기내에 존재하는 소화가 진행되기 전의 로티퍼 몸체의 수를 계수하는 방법으로 이루어졌다. 로티퍼의 체내에는 섬모환으로 모은 수중의 먹이 현탁액을 소화기계로 이동시키기 전에 먹이를 잘게 다지고 부수는 기능을 하는 저작기 (trophi)가 존재한다. 그리고 이 저작기는 로티퍼의 종에 따라서 다른 형태를 하고 있는 것으로 알려져 있다. 이 연구에서는 자어가 섭이한 로티퍼는 어류의 소화기내에서 소화가 진행되는 과정에서 로티퍼의 체 구조 중 저작기가 쉽게 소화되기 어렵고 소화기관의 연동 운동에 의해서도 쉽게 그 모양이 손상되지 않는다는 것을 발견하고 이 저작기의 수를 계수하므로서 로티퍼의 최초 섭이 일령 및 일령별 로티퍼 포식수를 계수할 수 있는 방법을 검토하였다. 그 결과, 소화기내의 잔존 로티퍼 몸체만으로 계수 관찰하던 기존 방법에 비교하여 로티퍼의 저작기를 계수하는 방법을 이용할 경우 보다 신뢰도가 높은 결과를 도출할 수 있음을 확인하였다. 경제적 가치의 우수성 때문만은 아니다. 미국은 자국의 대두 생산자들이 생산해 낸 대두를 판매하면서 조성한 자조금을 모아 대두의 생산성을 향상시키기 위한 연구 개발과 국내외 시장을 확대하기 위한 마케팅 활동에 쓰고 있다. 이런 자조 노력은 비단 미국의 대두 농민들에게만 국한된 것이 아니다. 가깝게는 일본의 수산업과 해산어 양식산업의 발전은 중앙 및 지방 정부, 수협과 같은 어민 조합 및 연근해 수산업 종사자들이 출연한 기금을 통해 이루어지고 있음을 지난 8월 북해도의 양식산업을 시찰했을 때 확인할 수 있었던 사실이다. 이제 우리나라도 국민소득 1만불 시대를 넘어 2만불 시대를 열기 위한 청사진을 그릴 만큼 모든 경제의 규모가 확대되었을 뿐 아니라 질적으로 고도화되었다. 우리에게 필요한 것은 성숙된 산업사회에 걸맞는 각 산업 주체들의 의식이다. 한국의 양식산업도 자조 정신을 갖추어 생산성 향상에 초점을 맞춘 양식기술의 개발, 환경 보전을 고려한 양식장 관리 및 소비를 확대하기 위한 유통시스템의 선진화에 스스로 투자를 해야 할 시기에 와 있다.치가 완전히 익은 15일 후에는 무첨가 김치, 0.1%, 0.2% 및 0.3% 고분자 키토산 김치의 젖산균 수는 5.4X107 cfu/g, 3.3X107 cfu/g, 8.6X106 cfu/g 및 2.6X106 cfu/g로 나타났다. 5. 발효가 진행 중에 대장균 군 수가 시간과 더불어 대장균군 수가 모든 구에 있어서 6일까지는 서서히 증가하다가 그 후부터는 대장균 군 수가 감소하였다. 즉, 발효초기에는 모든 구가 2.0X104∼4.0X105 cfu/g이었고, 6일 경에는 8.9X104∼4.5X105 cfu/g로 약간 증가하였으며 15일후에는 키토산 무첨가 김치가 2.0X

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.398-399
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• 2000

두족류는 연체동물문 두족강에 속하는 무척추동물로 해양에만 서식한다. 조간대에서 심해에 이르기까지 모든 해양 환경에 적응한 두족류는 뛰어난 유영능력과 감각기관을 가지고 활동적인 포식활동을 한다. 이빨고래류, 물개류, 상어류, 어류 등의 먹이가 되며 우리나라를 비롯한 북서태평양 연안국에서는 상업적으로도 중요한 수산자원생물이다. 국내에서는 분류학적 연구와 참갑오징어나 살오징어와 같은 일부 상업성 종류의 자원학적 연구가 이루어져 있으나 두족류 군집 전체를 대상으로 한 연구는 보고된 바 없다. 본 연구에서는 가덕도 주변 해역에 서식하는 두족류 군집의 종조성과 계절변동을 파악하고자 하였다. (중략)

• Journal of the Microelectronics and Packaging Society
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• v.31 no.1
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• pp.1-6
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• 2024

Spiders detect even tiny vibrations through their vibrational sensory organs. Leveraging their exceptional vibration sensing abilities, they can detect vibrations caused by prey or predators to plan attacks or perceive threats, utilizing them for survival. This paper introduces a nanoscale crack-based sensor mimicking the spider's sensory organ. Inspired by the slit sensory organ used by spiders to detect vibrations, the sensor with the cracks detects vibrations and pressure with high sensitivity. By controlling the depth of these cracks, they developed a sensor capable of detecting external mechanical signals with remarkable sensitivity. This sensor achieves a gauge factor of 16,000 at 2% strain with an applied tensile stress of 10 N. With high signal-to-noise ratio, it accurately recognizes desired vibrations, as confirmed through various evaluations of external force and biological signals (speech pattern, heart rate, etc.). This underscores the potential of utilizing biomimetic technology for the development of new sensors and their application across diverse industrial fields.

• Journal of Aquaculture
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• v.19 no.3
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• pp.178-182
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• 2006

We studied new observation method about take process of rotifer by marine fish larvae. Till now, we can not accurate observation and count of first rotifer feeding day and/or feeding numbers of rotifer by marine fish larvae. Because take rotifer is ingested and disappeared in the digestive system of fish larvae. However we suggest possible observation method for these problems. The trophi is mastication organ of rotifer, and has only one in each rotifer individual. The trophi is left in the mastication organ because sole indigestible organ of rotifer. Therefore we can accurate observation and count of first rotifer feeding day and/or feeding rotifer numbers of marine fish larvae by trophi observation method (RTCM; Rotifer Trophi Counting Method).

• Korean journal of applied entomology
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• v.58 no.1
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• pp.9-13
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• 2019

Nematode-trapping fungi use various specialized traps to capture nematodes. A fungus that can capture nematodes in three dimensional adhesive networks was isolated from the soil around the root of Cucumis melo L. (Oriental melon) in Seongju, Korea. The conidiophores were found to be septate, hyaline, erect and $290-528(342.8){\mu}m$ high. It produces obovoid shape and 1-3 septate (commonly 2-septate) conidia with a size of $30.5{\times}20.3{\mu}m$. Molecular analysis of 5.8 S rDNA displayed 99% similarity to Arthrobotrys sinensis. On the basis of morphological, morphometric and molecular studies, the fungus was identified as A. sinensis. It is the first report in Korea which can be one of biological control resource of plant-parasitic nematode.

• Korean Journal of Environmental Biology
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• v.26 no.3
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• pp.145-158
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• 2008

To assess the source of oyster (Crassostrea gigas) and clam (Ruditapes phillippinarum), phytoplankton community structures in the water column and sediment, including the composition of phytoplankton in oyster and clam digestive organs were investigated bimonthly from December 2006 to June 2007 in the Taeahn coastal waters. During the sampling period, water temperature and salinity varied from 7 to 23$^{\circ}C$ and 34 to 35 PSU, respectively. Total phytoplankton abundances at St. O in the water column were higher than those at St. J, whereas total phytoplankton abundances at St. O in the sediment were lower. In addition, total phytoplankton abundances in the water column and sediment were observed to be relatively higher in February and April 2007. Among the diatoms, Paralia sulcata was always dominant, accounting for 41$\sim$87% of total phytoplankton, except St. J for February 2007 during the sampling period. The following phytoplankton compositions observed in the digestive organs of oyster and clam appeared: diatoms such as genus Paralia, Navicula, Melosira and Coscinodiscus, Silicoflagellate Dictyocha, dinoflagellates Prorocentrum and Dinophysis. Phytoplankton compositions observed in the digestive organs of oyster and clam corresponded relatively well with the species composition appeared in the water column and sediments of each season. A significant relationship was found between individual weight of oyster or clam and their digestive organs weight, while there was not a close correlation with total phytoplankton amount. We suggest that P. sulcata always dominated as one of important the food source of oyster and clam in the marine ranching ground of Taeahn coastal waters.