• Korean journal of applied entomology
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• v.60 no.4
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• pp.379-386
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• 2021

Asian gypsy moth, Lymantria dispar asiatica (Lepidoptera: Erebidae), which is an indigenous pest in Korea, a large outbreak has been reported in Gyeonggi-do, Chungcheong-do, and northern Gyeongsangbuk-do from 2019 in forest and nearby downtown areas, causing emotional damage to forests and city dwellers. During the indoor culture of gypsy moth eggs collected in Yecheon, Gyeongbuk in 2021 we found that 79.65% (321/403 of first instar larvae) were died due to Lymantria dispar multiple nucleopolyhedrovirus (LdMNPV) infection. Sequence analyses of 36 gypsy moths collected from 12 regions in Korea using LdMNPV late expression factor-8 (lef-8) and polyhedrin (polh) genes showed a genetic variation of 0.80% and 0.86%, respectively. Comparison to GenBank data showed that the Korean samples were most similar to LdMNPV in Japan, whereas most different to those of Turkey. These results showed a high infection rate of LdMNPV in Korea and LdMNPV is one of the important population regulators of the gypsy moth.

• Nutrition Research and Practice
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• v.15 no.6
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• pp.686-702
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• 2021

BACKGROUND/OBJECTIVES: Schisandrae Fructus, the fruit of Schisandra chinensis Baill., has traditionally been used as a medicinal herb for the treatment of various diseases, and has proven its various pharmacological effects, including anti-inflammatory and antioxidant activities. In this study, we investigated the inhibitory effect of Schisandrae Fructus ethanol extract (SF) on inflammatory and oxidative stress in particulate matter 2.5 (PM2.5)-treated RAW 264.7 macrophages. MATERIALS/METHODS: To investigate the anti-inflammatory and antioxidant effects of SF in PM2.5-stimulated RAW 264.7 cells, the levels of pro-inflammatory mediator such as nitric oxide (NO) and prostaglandin E₂ (PGE₂), cytokines including interleukin (IL)-6 and IL-1β, and reactive oxygen species (ROS) were measured. To elucidate the mechanism underlying the effect of SF, the expression of genes involved in the generation of inflammatory factors was also investigated. We further evaluated the anti-inflammatory and antioxidant efficacy of SF against PM2.5 in the zebrafish model. RESULTS: The results indicated that SF treatment significantly inhibited the PM2.5-induced release of NO and PGE₂, which was associated with decreased inducible NO synthase and cyclooxygenase-2 expression. SF also attenuated the PM2.5-induced expression of IL-6 and IL-1β, reducing their extracellular secretion. Moreover, SF suppressed the PM2.5-mediated translocation of nuclear factor-kappa B (NF-κB) from the cytosol into nuclei and the degradation of inhibitor IκB-α, indicating that SF exhibited anti-inflammatory effects by inhibiting the NF-κB signaling pathway. In addition, SF abolished PM2.5-induced generation of ROS, similar to the pretreatment of a ROS scavenger, but not by an inhibitor of NF-κB activity. Furthermore, SF showed strong protective effects against NO and ROS production in PM2.5-treated zebrafish larvae. CONCLUSIONS: Our findings suggest that SF exerts anti-inflammatory and antioxidant effects against PM2.5 through ROS-dependent down-regulating the NF-κB signaling pathway, and that SF can be a potential functional substance to prevent PM2.5-mediated inflammatory and oxidative damage.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.449-462
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• 2021

We analyzed the effects of temperature on the survival, development, and reproduction of the non-diapause Asian corn borer, Ostrinia furnacalis (Lepidoptera: Crambidae). A 16:8 h light:dark photoperiod was supplied to the non-diapause stages of O. furnacalis. The insects were raised on an artificial diet at seven constant temperatures between 15 and 35℃ for immature stages, and eight temperatures between 13 and 33℃ for the adult stage. The survival rate of eggs exceeded 70% at all temperatures, whereas survival of larvae was as low as 7.4% at 15℃. The developmental periods of the immature stages decreased with increasing temperature, but the larval period did not decrease further at 35℃. The pupal weight increased with increasing temperature, but the female weight decreased at 35℃. Variations with different last larval instars within the colonies at different temperatures were observed. Adults produced offspring at all tested temperatures. Adult longevity and the pre-oviposition and oviposition periods decreased with increasing temperature, but the pre-oviposition period increased at 33℃. Total fecundity exceeded 400 viable eggs at 22℃ and 31℃. The mean daily fecundity during the oviposition period and the mean daily fecundity on the day of oviposition increased with increasing temperature, but decreased at 33℃. Daily fecundity sharply increased at earlier adult ages and slowly decreased thereafter. The simulated oviposition frequency was greatest at 22℃. The lower developmental threshold temperatures were estimated to be the lowest at 9.7℃ for the first instar larva and the highest at 14.7℃ for the 5th to last instar larval stage, using a linear model.

• Journal of Marine Life Science
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• v.4 no.1
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• pp.14-21
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• 2019

This review paper discussed the decadal fluctuations in the catch of the common squid, Todarodes pacificus (T. pacificus) by focusing on migration and distribution patterns. Since 1980s, changes in T. pacificus catches were due to climate regime shift in Korean waters. Fluctuation patterns of catches were different between the East Sea and the Yellow Sea. Generally PDO (Pacific Decadal Oscillation) phase shows a negative correlation with strength of warm current to the East Sea. In 1980s when PDO was positive phase (+), T. pacificus catch was higher in the Yellow, but it was lower in the East Sea. In 1990s when PDO was negative phase (-), T. pacificus catch showed opposite trend compared with 1980s. Such spatial and decadal fluctuations of T. pacificus catch were due to its northward migration along with the warm current or southward movement against the current. In the East Sea, strong (weak) warm current period, the current path has been shifted toward the East Sea coast of Korea (central East Sea or the coast of Japan). It has a correlation with PDO. In the positive PDO phase (1980s), the fishing ground was located on the eastern side of Ulleungdo, whereas during negative PDO phase (1990s), they were situated near the southeastern coast of the Korean peninsula. In the 1980s, volume transport passing into the Yellow Sea increased, whereas volume transport in the East Sea decreased. This is one of major reason increasing T. pacificus larvae in the Yellow Sea.

• Korean journal of applied entomology
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• v.58 no.3
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• pp.175-182
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• 2019

The citrus leafminer, Phyllocnistis citrella (Lepidoptera: Gracillaridae), is an important pest that decreases the productivity of citrus trees by attacking citrus leaves, and especially it causes a severe damage during the young growth stage. In this study, we investigated the distribution of eggs on the leaves of shoots according to the position and the survival rate of this pest in the field condition. The occurrence patterns of P. citrella eggs in citrus orchards were largely affected by the occurrence of shoots. Even if the adults were still being attracted in the pheromone traps, the eggs were not observed on leaves when the growth of shoots was stopped. The density of P. citrella eggs in the citrus shoots peaked at the fifth or sixth leaf from the terminal leaf, and over 90% of the eggs were found in the first to eighth leaves as a whole. In 2015 and 2016, the average survival rate of larvae surviving to pupa was 1.4%, and the rate of survival to adults was 0.2%, indicating that most of them died. Furthermore, we have discussed the management strategy of P. citrella considering the distribution of eggs and the larval survival rate in the citrus shoots.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.423-428
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• 2018

Anaerobic growth-inhibiting and acaricidal activities of 2'-hydroxy-5'-methoxyacetophenone derived from Cyanachum paniculatum oil and its derivatives against five intestinal bacteria (Bifidobacterium bifidum, B. longum, Clostridium pefringens, Escherichia coli and Lactobacillus casei) and Haemaphysalis longicornis were examined. In the packet test against the larvae of H. longicornis, none of the C. paniculatum oil exhibited acaricidal activity, while the C. paniculatum oil showed only antimicrobial activity against five intestinal bacteria in the disc diffusion method. Based on the inhibition zones and MIC values, 2',4'-dimethoxyacetophenone, 2',5'-dimethoxyacetophenone, 2'-hydroxy-4'-methoxyacetophenone, 2'-hydroxy-5'-methoxyacetophenone, 2'-methoxyacetophenone, and 4'-methoxyacetophenone, containing a methyl group on the acetophenone skeleton, possessed growthinhibiting activities against C. perfringens and E. coli. However, acetophenone, 2'-hydroxyacetophenone, 4'-hydroxyacetophenone, 2',4'-hydroxyacetophenone and 2',5'-hydroxyacetophenone, which contained a hydroxyl group on the acetophenone skeleton, had no growth-inhibiting activity against intestinal bacteria. These results indicated that 2'-hydroxy-5'-methoxyacetophenone and its derivatives could potentially be developed as natural antimicrobial agents to specific control of C. perfringens and E. coli.

• Korean Journal of Ichthyology
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• v.31 no.3
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• pp.131-140
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• 2019

This study is to observe species identification and early life history of Gnathopogon strigatus and to use it as a basis for taxonomic studies and conservation of species. For the experiments, the mature adults were collected at the Wang-suk Stream located in Namyang-ju city, Gyeong-gi Province and eggs were artificially fertilized by the wet method in the laboratory. The shape of the fertilized egg was globular, adhesive, opaque white in color and had no oil globules. The fertilized egg was 1.66~1.88 mm (average 1.76 mm, n=30) in diameter. The blastular stage occurred at 3 hours 05 minutes after fertilization and the gastrular stage was detected at 8 hours 30 minutes after fertilization. The embryo began to hatch about 54 hrs after fertilization under water temperature of $23{\pm}1^{\circ}C$ and the newly hatched larva (yolksac larva) were 4.1~4.7 mm (mean 4.4 mm, n=20) in total length (TL). The fourth day after hatching, the postlarva were 5.4~5.9 mm (mean 5.6 mm, n=20) in total length, their york sacs were completely absorbed and Start eating Artemia sp. Ten days after hatching, flexion larva were begins Notochord flexion were 7.5~8.6 mm (mean 8.1 mm, n=20) in total length. Sixteenth day after hatching, postflexion larva were complete Notochord flexion were 8.2~9.7 mm (mean 9.1 mm, n=20) in total length. At thirty-eight days after hatching, Juvenile were arrive integer all fin rays and similar to those of adults were 11.3~15.5 mm (mean 13.3 mm, n=20) in total length.

• Korean Journal of Ichthyology
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• v.31 no.1
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• pp.30-38
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• 2019

Egg development and early life history of the Korean endemic sand spine loach, Cobitis nalbanti, were investigated in the present study. Adult fish were sampled using spoon nets at the Yeongsan River in Seongam-ri, Bukha-myeon, Jangseong-gun, Jeollanam-do, Korea, June 2011. Eggs were obtained after injecting Ovarprim into females. Eggs were then artificially fertilized using the dry method in the laboratory. Mature eggs were transparent and slightly adhesive with light yellowish coloring, measured $0.99{\pm}0.03mm$ ($mean{\pm}SD$) in diameter. And number of spawned eggs were $1,527{\pm}410$ per individual. Hatching (50%) of the embryo occurred 52 hours after fertilization a water temperature of $25^{\circ}C$, and the average newly hatched larvae size was about $4.2{\pm}0.22mm$ in total length. At fifth day after hatching, the larval total length reached $6.0{\pm}0.34mm$ on average and their yolk sac had been completely absorbed. At fifteen day after hatching, larva entered the juvenile stage and reached $10.8{\pm}0.45mm$ in total length. At 100th day after hatching, the formation of Gambetta's zone of four dotted line was complete and juveniles were similar in general appearance to adults, and they averaged $41.1{\pm}2.95mm$ in total length.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.92-92
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• 2019

Excessive or chronic inflammation contributes to the pathogenesis of many inflammatory diseases such as sepsis, rheumatoid arthritis, and ulcerative colitis. Hibiscus syriacus L. has been used as a medicinal plant in many Asian countries, even though its anti-inflammatory activity has been unclear. Therefore, we investigated the anti-inflammatory effect of anthocyanin fractions from the H. syriacus L. varieties Pulsae (PS) on the lipopolysaccharide (LPS)-induced expression of proinflammatory mediators and cytokines in RAW264.7 macrophages. PS suppressed LPS-induced nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) secretion concomitant with downregulation of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) expression. Furthermore, PS inhibited the production of proinflammatory cytokines such as tumor necrosis factor-alpha ($TNF-{\alpha}$), interleukin-6 (IL-6), and IL-12 in LPS-stimulated RAW264.7 macrophages. Further study showed that PS significantly decreased LPS-induced nuclear translocation of the nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) subunits, p65 and p50. Molecular docking data showed that many anthocyanins from PS fit into the hydrophobic pocket of MD2 and bound to Toll-like receptor 4 (TLR4), indicating that PS inhibits the TLR4-MD2-mediated inflammatory signaling pathway. Especially, apigenin-7-O-glucoside most powerfully bound to MD2 and TLR4 through LYS122, LYS122, and SER127 at a distance of $2.205{\AA}$, $3.098{\AA}$, and $2.844{\AA}$ and SER441 at a distance of $2.873{\AA}$ (docking score: -8.4) through hydrogen bonding, respectively. Additionally, PS inhibited LPS-induced TLR4 dimerization/expression on the cell surface, which consequently decreased MyD88 recruitment and IRAK4 phosphorylation. PS completely blocked LPS-mediated mortality in zebrafish larvae by diminishing the recruitment of neutrophil and macrophages accompanied by low levels of proinflammatory cytokines. Taken together, our results indicate that PS attenuates LPS-mediated inflammation in both in vitro and in vivo by blocking the TLR4/MD2-MyD88/IRAK4-$NF-{\kappa}B$ axis. Therefore, PS might be used as a novel modulatory candidate for effective treatment of LPS-mediated inflammatory diseases.

• Journal of Life Science
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• v.31 no.2
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• pp.219-222
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• 2021

In this study, we examined low molecular weight peptides using proteomics in order to identify their original proteins, derive their peptides, and determine the functions of the proteins in Tenebrio molitor, the mealworm (larvae, pupae, or adult) from which the peptides were extracted. Fifty-four proteins were finally identified through an analysis of proteome to derive the analyzed peptides. The proteins that induced low molecular weight peptides were identified to be the most abundant in adults only, and the next highest were derived from a group containing both adults and larva. However, other groups, including pupa, were detected to have a lower frequency of peptides. As a result of orthologous classification of the detected proteins, the general function prediction was only investigated at the highest frequency among the examined proteins. Proteins related to chromatin structure and dynamics were detected by their higher frequency among functional classes. The next highest frequency was shown by proteins related to amino acid transport and metabolism and carbohydrate transport and metabolism. Therefore, it is assumed that proteins correlated with chromatin, amino acid, and carbohydrate metabolisms are easily induced into low molecular weight peptides, and that their peptides could play a role as bioactive substances.