• Journal of Aquaculture
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• v.19 no.2
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• pp.77-83
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• 2006

This study was conducted to investigate changes of hemolymph count, antioxidant enzyme activities (catalase: CAT and superoxide dismutase: SOD) and Heat Shock Protein 70 (HSP70) mRNA in hemolymph, hepatopancreas and gill of abalone (Haliotis sieboldii) exposed to various water temperatures. Abalones were exposed to 10, 15, 20, 25 or $30^{\circ}C$ for 0, 6, 12, 24 or 48 hours. Survival rate of abalone was 100% at 10, 15, 20 and $25^{\circ}C$, but 0% at $30^{\circ}C$. Hemolymph counts increased at lower water temperatures (10 and $15^{\circ}C$) and decreased at $30^{\circ}C$. SOD activity decreased immediately after exposure to lower or higher water temperatures compared to the control ($20^{\circ}C$) with an exception at $30^{\circ}C$ where the activity increased. At lower temperatures, SOD activity rose high after 24 hours, but decreased again at 48 hours. At $25^{\circ}C$, it decreased compared to the control. CAT activity decreased immediately after exposure to 10 or $25^{\circ}C$ compared to the control, and then was recovered to the initial level after increment. At $15^{\circ}C$, CAT activity was high after 6 hours, and then was recovered to the initial level after increment. At $30^{\circ}C$, the activity decreased throughout the experiment. The HSP70 mRNA expression in gill increased at lower temperatures compared to the control ($20^{\circ}C$) and $25^{\circ}C$. In this study, rapid change of wale, temperature caused stress response in abalone which had been raised at $20^{\circ}C$. At molecular level, HSP70 was expressed rapidly, but antioxidant enzymes like SOD and CAT were expressed later than HSP70. At 15 and $25^{\circ}C$ of water temperatures, the HSP70, SOD and CAT expression were stable with time. However, at $30^{\circ}C$, all abalone died possibly because they could not develop resistance to high temperature.

• The Korean Journal of Malacology
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• v.29 no.2
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• pp.129-137
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• 2013

This study was conducted to find out the changes of survivorship, respiration and organ structure of Mactra veneriformis exposed to copper (Cu). Experimental period was four weeks. Experimental groups were composed of one control condition and three copper exposure conditions (0.025, 0.050 and 0.100 mg/L). The results of the study confirmed that copper induces reduction of survival rate and respiration rate and histopathology of organ structure of the bivalve. In the copper concentration of 0.100 mg/L, mortality was 100% after Cu exposure of 3 weeks. Respiration rate was observed exposure groups lower than control decline by 75%. Histological analysis of organ system illustrated expansion of hemolymph sinus, disappearance of epidermal layer and degeneration of connective tissue layer of the mantle. Also, histological degenerations as epithelial necrosis and hyperplasia of mucous cells are recognized in the gill and it was observed expansion of hemolymph sinus, disruption of epithelial layer, decrease of mucous cell and degeneration of connective tissue layer in the foot. In the digestive diverticulum, it was showed atrophy of basophilic cell and degeneration of epithelial cell in the digestive tubules, and as the concentration of copper increased the accumulation of lipofuscin increased.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.221-227
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• 1996

Four strains of Beauveria bassiana F101, F587, F9 and FJ8, were received from Forestry Research Institute,Seoul. The strain, B. bassiana F101, was the most active in the enzymatic activity and spore production. Whenspores of B. bassiana FlOl were sprayed on the female larva of the black tipped sawfly with various concentrationsof 6 xl 0'~-10s~p ores/ml, insects started to die from 5-7 days, and were covered with mycelia andspores in 24-28 days at 25"C, while the insect did not show visible symptoms even after 50 days at 4'C. Theinsect injected with 5 pl of spore solution (3X l0'~-10s~p oreslml) died within 30-98 and 38-218 hours at25$^{\circ}$C and 4"C, respectively. About 3 days (60 hours) after the injection with a concentration of 3 x lo9 spores1ml, at the point of the insect's death, lots of proteins started to disappear '||'&'||' the hemolymph, fat body and carcaseat 25'C. Esterase activity in the tissues was gone suddenly after that time. Six days after the spray, manyprotein and esterase bands were lost in the hemolymph, but not those in the fat body and carcase. When thefungi growing in the host were exposed in the air, they put energy for spore production, while numerous longand thin mycelia branched out from the host body in the soil.e host body in the soil.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.146-152
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• 1996

The adult of the aphidophagous ladybeetle, Harmonia axyridis, was reared by feeding an artificial diet (chicken's 1iver:sugar = 5:2, v/w). The adult ladybeetle used was from pupae collected in the field in midJuly. Yolk protein production, fecundity and longevity of the adult female were checked under 3OoC, 16L:8D. Yolk proteins (Vg3 and Vg4) were detected from the hemolymph of the female 5 days after the emergence. One hundred pairs of female and male were reared separately. First oviposition started from 7 days afier the emergence and laid an average of 163.9k144.0 eggs during lifetime. Seventeen females did not lay eggs at all. Longevity of the female was 60.6k16.9 days. The application of a JH analog, methoprene (2.5 pg), caused the occurrence of yolk proteins in the hemolymph 1 day earlier than that of the control. Weekly application of 2.5 pg of methoprene induced 83.3% from the 30 females to lay eggs within 15 days after the emergence, while the control had 51% only. Methoprene made all females lay eggs, causing the increase in the fecundity. Though the longevity of the female was not effected by the weekly application of methoprene, one time excess dose (12.5 pg) caused high in mortality and low in fecundity.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.179-185
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• 1998

The effect of physiological factors of beet armyworm, Spodoptera exigua (Hubner), on esterase variation was analyzed by comparing electrophoretic esterase isozymes. Each esterase isozyme was also characterized by substrate and inhibitor specificities. A total of 28 esterase isozymes were separated on 10% nondenaturing polycarylamide gel electrophoresis (PAGE). These isozymes were denoted from El to E28 according to cathodal migration distances. There was a variation in esterase isozymes among developmental stages. Larvae and pupae had more isozymes than did adults. Eggs had only eight isozymes. The isozymes of El and E2 were specific only in the first instar larvae. Esterases also showed variation according to different tissues. More kinds of esterase isozymes were found in epidermis and gut tissues than in hemolymph and fat body. Some isozymes were specific in epidermis (from El to E6), gut (E10, El 1, E25, E26, and E27), and hemolymph (E18). Among 10 naphthyl esters, a-naphthyl propionate was the most reactive substrate to the esterase isozymes. The isozymes were classified into cholinesterases (El0 and E24), arylesterases (E4, E9, E17, E19, E21, and E23), and carboxylesterases (the others) on the basis of inhibition by the esterase inhibitors-eserine, dichlorovos, moncrotophos, and paraoxon.

• Journal of Life Science
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• v.26 no.6
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• pp.737-748
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• 2016

By this time, insect antimicrobial peptides (AMPs) have been characterized more than 150 peptides since purification of cecropin in the hemolymph of pupae from Hyalophora cecropia in 1980. Therefore, it is considered that insects are good sources of AMP selection. Insect AMPs are small (low molecular weight) and cationic, and amphipathic with variable length, sequence, and structure. They perform a pivotal role on humoral immunity in the insect innate immune system against invading pathogens such as bacteria, fungi, parasites, and viruses. Most of the insect AMPs are induced rapidly in the fat bodies and other specific tissues of insects after septic injury or immune challenge. Then the AMPs subsequently released into the hemolymph to act against microorganisms. These peptides have a broad antimicrobial spectrum against various microbes including anticancer activities. Insect AMPs could be divided into four families based on their structures and sequences. That is the α-helical peptides, cysteine-rich peptides, proline-rich peptides, and glycine-rich peptides/proteins. For instance, cecropins, insect defensins, proline-rich peptides, and attacins are common insect AMPs, but gloverins and moricins have been identified only in lepidopteran species. This review focuses on AMPs from insects and discusses current knowledge and recent progress with potential applications of insect AMPs.

• The Korean Journal of Zoology
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• v.28 no.1
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• pp.44-59
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• 1985

The epithelium of the hindgut in the german cockroach, Blattella germanica Linne, was observed with electron microscope. The epithelium of the ileum, which is located at the anterior hindgut, is composed of a single layer of squamous and cuboidal cells. The liminal surface of the epithelium is lined with the cuticular intima. The epithelial cells contain cell organelles expected to be found in absorptive cells, and some epithelial cells have numerous lamelated crystals, the "spherites". The rectal epithelium of posterior hindgut is composed of rectal pads which are covered with cuticular intima on the luminal side. The rectal pads are composed of columnar absorptive cells and basal cells. The apical plasma membrane of columnar cell is made of microvilli, where mitochondria associated with some of the microvilli. The lateral plasma membrane is highly infolded and space is an uniform width of approximately 200$\\AA$. Well developed mitochondria are found closely associated with the infoldings and this is referred to as the "mitochondrial-scalariform complex". A septate junction is found near the apical zone between the columnar absorptive cells, whereas many desmosomes and intercellular spaces are formed between the columnar cells. Basal cells are bowl-shaped where the convex surface is inlaid into the basal surface of the columnar cells while the concave surface faces the basal lamina. The cytoplasm of the basal cell is electron dense and contains well developed cell organelles. The basal sheath is located between the basal membrane and basal lamina, providing barrier between the epithelium and the hemolymph. The epithelium is surrounded by the subepithelial space and muscles. The subepithelial space, which is composed of fibrous connective tissue, is innervated by many tracheoles and axons.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.2
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• pp.131-135
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• 2000

The vitellin of the fireflies, Luciola unmunsana and L. lateralis was characterized. The vitellin of L. unmunfon is composed of two subunits, designated Vnl (195 kDa) and Vn2 (185 kDa) in SDS-polyacryamide gel electrophoresis. These two subunits of vitellin of L. unmunsana gradually decreased during embryogenesis. As expected, these protein bands were presented in female adult hemolymph and egg extracts, but not in male. The vitellin of L. lateralis is also composed of two subunits, designated Vnl (195 kDa) and Vn2 (180 kDa) in SDS-PAGEi and these two protein bands gradually decreased during embryogenesis. Western blot analysis using each of polyclonal antiserum against vitellins of L. unmunsana and L. lateralis showed that two antisera strongly crossereacted with vitellin subunits of L. unmunsana and L. lateralis, suggesting that vitellins of L. unmunsana and L. lateralis have similarity with each other.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.2
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• pp.205-211
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• 2002

Previously, genetic relationships among 321 silkworm races preserved in the Department of Sericulture and Entomology, NIAST, RDA were studied using six isozymes comprising 20 loci. As a part of additional studies, three additional isozymes with 7 loci [phos-phoglucomutase (PGM), glucose phosphate isomerase (GPI), malete dehydrogenase (MDH)] from hemolymphs, midgets, and eggs were employed to reevaluate the previous dendrogram (UPGMA method). Although the current study supported the recognition of the previously identified major groups, some minor changes were apparent among the selected 47 forms. The current study showed that the polymorphic loci of GPI from eggs and MDH from hemolymph appear to be responsible characters for generating a new major group in the genetic relationship. Interpreting the data with current additive isozymes may represent more robust genetic relatioships among 321 silkworm races preserved in Korea, until further evidence is available.

• International Journal of Industrial Entomology and Biomaterials
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• v.2 no.1
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• pp.55-59
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• 2001

The vitellin of the red flour beetled Tribolium castaneum Herbst was purified and characterized. The vitellin of T. castaneum was purified by the FPLC techniques, anion exchange chromatography and gel permeation chromatography. In native-polyacrylamide gel electrophoresis, vitellin of T. castaneum was detected as a single band. This native vitellin has molecular weight of 440 kDa. The vitellin of T. castaneum is composed of three polypeptides, designated Vnl (178 kDa), Vn2 (168 kDa) and Vn3 (52 kDa) in SDS-polyacrylamide gel electrophoresis. Three subunits of vitellin were presented in the female adult hemolymph and egg extracts, but not observed in the male. These three polypeptides gradually decreased during embryogenesis. Polyclonal antiserum raised against purified vitellin reacted with the three polypeptides, Vnl, Vn2 and Vn3. Antisera raised against Vn1 and Vn2 cross-reacted with the two large subunits, Vnl and Vn2, respectively. Another subunits Vn3, however, was not cross-reacted with these two antisera. Also, antiserum raised against Vn3 did not cross-react with the Vn1 and Vn2.