• Journal of Sericultural and Entomological Science
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• v.17 no.2
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• pp.125-132
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• 1975

• Biotechnology and Bioprocess Engineering:BBE
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• v.4 no.1
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• pp.12-16
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• 1999

Xenorhabdus nematophilus sp., an insect-pathogenic bacterium, was newly isolated from Korean entomopathogenic nematode of Steinernema carpocapsae, which can be used as a useful bioinsecticide. Primary and secondary form variants of Xenorhabdus nematophilus were observed when cultured in vitro. Primary form variants adsorbed bromothymol blue, while secondary form did not. However, many other characters of two variants were very similar. The variants were all rod-shaped and cell size was highly variable ranging from 0.5 by 2.0 ${\mu}$m to 1.0 by 5.0 ${\mu}$m. Both produced highly toxic substances and killed the insect larva within 20∼38 hr, indicating that insect pathogenicity of Xenorhabdus is not directly associated with its phase variation. In addition, cell-free culture supernatant of Xenorhabdus was sufficient to kill the insect larva by injecting it ito insect hemolymph; however, cell-harboring culture broth was more effective for killing the insect. The use of Xenorhabdus nematophilus may provide a potential alternative to Bacillus thuringiensis (Bt) toxins.

• KSBB Journal
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• v.14 no.2
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• pp.198-204
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• 1999

Asymbiotic bacterium with highly effective toxins was isolated from entomopathogenic nematode Steinernema glaseri which has been widely used against various soil-inhabiting pests. The symbiont of S. glaseri was identified as Xenorhabdus nematophilus sp. by using several biochemical and physiological tests. When this strain was released into the hemolymph of insect larva, it produced highly toxic substances and killed the larva within 2 days. Two colony forms that differed n some biochemical characteristics were observed when cultures in vitro. Phase l colonies were mucid and difficult to be dispersed in liquid. Phase II was not mucoid and was easily dispersed in liquid. It did not adsorb neutral red or bromothymol blue. Rod-shaped cell size was highly variable between two phases, ranging 2-10 ${\mu}{\textrm}{m}$. It was also found that only infective-stage nematodes can carry only primary-phase Xenorhabdus in their intestine.

• Applied Microscopy
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• v.21 no.2
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• pp.29-38
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• 1991

Ventral nephrocytes in the larva of the Lucilia illustris comprise ellipsoid cells situated onto the salivary glands. The cells are $60{\sim}100{\mu}m$ in diameter. Junctional complex beneath the basement membrane hold the plasma membrane in a even contour. Intracellular channels from the juntion complex are well developed at the cortex part of the cell. Coated vesicles pinched off from the channels seems to be connected with the ${\alpha}$-vacuoles via the tubular elements, which is regared as selective absorption system from the hemolymph. Two nuclei are sometimes observed in the medulla part of the cell. Ventral nephrocytes contain well-developed rough endoplasmic reticulum and Golgi complex, and numerous mitochondria. These cellular organelles synthesize lysosome. The lysosome not only digest some cell organells but also seems to be related with the ${\beta}$-vacuoles.

• Parasites, Hosts and Diseases
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• v.39 no.2
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• pp.193-196
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• 2001

We report a case of gastric pseudoterranoviasis proven by gastrofiberscopy on Dec. 13, 1994. The 34-year-old male patient, residing in Chungju-shi, was admitted to Konkuk University Hospital complaining of prickling epigastric pain. The symptoms suddenly attacked him two days after eating raw marine fish at Chonan-shi. By the gastrofiberscopic examination, a long white-yellowish nematode was found from the fundus region of stomach. The worm was $34.50{\;}{\times}{\;}0.84{\;}{\;}mm$ in size. and was identified as a 3rd stage larva of Pseudoterranova decipiens judging from the position of the intestinal cecum. This is the 12th confirmed case of human pseudoterranoviasis in Korea.

• Animal Systematics, Evolution and Diversity
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• v.33 no.1
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• pp.56-59
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• 2017

The external anatomy of the immature stages (last instar larva and pupa) of the crane fly, Tipula (Nippotipula) sinica Alexander, 1935 (Diptera: Tipulidae) is described and illustrated from specimens first collected in Korean peninsula (South Korea). Comments concerning natural history and microhabitats of larvae are provided. This is the first detailed description with illustrations for the last instar larva and pupa of Tipula (Nippotipula) sinica. Pupal characteristics resemble those of most species from advanced lineages within the subfamily Tipulinae. And, also it described with habitats and biological notes of Tipula (Nippotipula) sinica. Crane fly larvae, categorization as found in this survey indicate a taxonomic stream and are expected to help.

• Korean Journal of Ichthyology
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• v.17 no.3
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• pp.217-220
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• 2005

Three specimens of leptocephalus larvae (33.4~35.2 mm in SL) were collected from the southern coast of Jeju Island, Korea, by an aquatic lamp on August 14, 2004. These larvae were identified as Elops hawaiensis because of their having a forked caudal fin, a smaller anal fin than dorsal fin, and anal-fin position posterior to dorsal fin.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.231-233
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• 2003

To understand the physical method for induction of anti-bacterial substances from the silkworm larvae, Bombyx mori, three physical methods, i.e., infrared radiation, ultraviolet radiation and ultrasonic wave, have been used in this study. The results have shown that ultrasonic wave can induce anti-bacterial sub-stances effectively than radiations in the B. mori larva. The induction of anti-bacterial substances was different from silkworm race to race. Summer-autumn silkworm race (Qiufeng${\times}$Baiyu) was easy to induce antibacterial substances. It is suggested that the ultrasonic wave is a simple and easy method for induction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.479-484
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• 2000

흰쥐에 에탄올을 투여해 간 손상을 유도한 후 굼벵이를 투여해 굼벵이가 혈청과 간의 지진대사에 어떠한 영향을 미치는가를 조사하였다. 혈청지질 중 에탄올에 의해 증가된 triglyceride, 총 cholesterol은 굼벵이를 섭취시킴으로써 이의 수치를 감소시켰으며 HDL-cholesterol은 굼벵이의 섭취로 triglyceride 함량은 감소되었다. GOT와 GPT의 활성은 에탄올 투여시 정상식이에 비해 유의적인 증가를 보인 반면, 굼벵이의 섭취로 유의적인 감소를 나타내었다. (p<0.05). 에탄올 추여군의 간조직 세포는 세포질에 지방소적의 축적으로 세포질의 부분적인 괴사현상이 나타났으며 조면소포체와 mitochondria의 형태적 변형이 관찰되었다. 에탄올과 굼벵이의 병용투여군은 지방소적의 크기 및 양적 감소와 세포질의 괴사현상이 약간 회복 되었으나 조면소포체와 mitochondria의 수적인 증가는 미미하였다.

• The Korean Journal of Mycology
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• v.44 no.4
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• pp.355-359
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• 2016

During a survey of fungal diversity in insect guts in Korea, two fungal strains, EML-PGH2 and EML-PUKI88, were isolated from the gut of grasshopper and soldier fly larvae inhabiting the bulrush plants at a pond located in the Chonnam National University Arboretum, Gwangju, Korea. Based on their morphological characteristics and a phylogenetic analysis of the internal transcribed spacer (ITS1 and ITS2) and 5.8S rDNA sequences, the strains were identified as Blakeslea trispora. To our knowledge, the zygomycete species B. trispora has not been previously described in Korea.