• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.16-20
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• 2000

The aqueous extract from the cultural mycelium of Paecilomyces japonica showed cytotoxicity against several tumor cells including Jurkat, U937, HL-60, HepG2, BW5147.G.1.4, and NIH3T3. When the aqueous extract was fractionated by sequential organic solvent extractions using n-hexane and ethyl acetate, the ethyl acetate fraction appeared to contain the most cytotoxic activity, and the $IC_{50}$ values for various tumor cells were in the range from 1.5 to $10.0{\;}\mu\textrm{g}/ml$. To elucidate the cellular mechanism underlying the induced cytotoxicity, the apoptotic DNA fragmentation along with the cell cycle proression was examined in Jurkat T cells following the ethyl acetate fraction treatment. In the presence of $2.5{\;}\mu\textrm{g}/ml$ of the ethyl acetate fraction, apoptotic DNA fragmentation of the cells was detected within 1 h and increased upto 24 h in a time-dependent manner. Under the same conditions, a sub-G1 peak was detectable by flow cytometry. These results indicate that the cytotoxic effect of P. japonica on tumor cells is attributable to the induced apoptosis.

• Nutritional Sciences
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• v.9 no.1
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• pp.9-13
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• 2006

The differential effects of various fatty acids such as n-3 and n-6 types or degrees of unsaturation on the CYP2E1 induction and the production of lipid peroxidation (LPO) were investigated. The CYP2E1-transduced human hepatoma HepG2 cells (E47) were cultured in RPMI 1640 media containing different concentrations of various fatty acids up to 48 h incubation compared to 04 cells and CYP2E1-null cells. Treated fatty acids were linoleic acid (LA:n-6, C18:2), arachidonic acid (AA:n-6, C20:4) and docosahexaenoic acid (DHA:n-3, C22:6). The cell survival rate was decreased corresponding to the degree of unsaturation (LA>AA $\cong$DHA) and to LPO production in E47 and 04 cells. The four or five unsaturation degree of fatty acids, AA and DHA, caused time- and dose-dependent cell death in E47 cells but not as much as in C34 (without CYP2E1), suggesting an important role of CYP2E1 in the DHA mediated damage. In the levels of lipid peroxides (LPO), AA also elevated LPO by 3- and 5- fold compared to DHA or LA treated E47 cells. However, AA did not increase LPO until 48 h incubation in C34 cells. In conclusion, the polyunsaturated fatty acids induced CYP2E1 induction might be changed by the elevated levels of lipid peroxide (LPO) and oxidative stress through the connection of CYP2E1 and degrees of unsaturated fatty acids.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.197-202
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• 2009

The Luciola lateralis larva took 5.3 days from climbing on the land to the pupal cocoon formation. It took 6.6 days for a larva to eventually transform to a pupa after building a pupal cocoon. The size of pupal cocoon was 10.1 mm in length, 4.7 mm in width and its wall thickness was 1.3 mm. The mean pupal period was 10.5 days. The adult stayed 6.8 days in the pupal cocoon before escaping the cocoon. The peak adult emergence appeared around 9 p.m., and decreased after 10 p.m. The optimal soil temperature for emergence was $23.4^{\circ}C$. The female adult of the natural population (Nat-type) lived shorter, laid fewer eggs, and the oviposition frequency was fewer than that of the Lab-type individuals. However, a few individuals from the natural population laid 200-400 eggs. The less number of oviposition in the natural population may be due to the fact that the female adults might lay eggs before the collection for the experiment.

• Journal of Korean Society of Forest Science
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• v.95 no.2
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• pp.174-176
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• 2006

The experiments were conducted by supplying hosts with natural food(chestnut, peach, Quince). The developmental difference of peach pyralid moth, Dichocrocis punctiferalis was examined in the laboratory under three different natural food regime. The periods of egg, larva and pupa were $6.01{\pm}0.07$, $12.23{\pm}0.03$ and $13.32{\pm}0.01$ days on the chestnut fruit, $6.21{\pm}0.01$, $18.69{\pm}0.02$ and $13.38{\pm}0.03$ days on the peach fruit and $7.02{\pm}0.04$, $22.62{\pm}0.04$ and $13.44{\pm}0.14$ days on the quince fruit, respectively. The growth of D. punctiferalis larva was better chestnut fruit than other tested fruits. The rates(%) of hatching, pupation and emergence were 94.0, 57.0 and 63.3 on the chestnut fruit, 89.2, 77.8 and 85.7 on the peach fruit and 79.6, 52.6 and 70.7 on the quince fruit, respectively. The survival rate(%) of D. punctiferalis from hatching to emergence were 31.0 on the chestnut fruit, 4.8 on the peach fruit and 14.3 on the quince fruit, respectively. The sex ratio (female: male) of all pupae obtained on the tested natural food fruits were 52.7 : 47.3. The sex ratio of D. punctiferalis reared on three difference food fruits were no significantly. It can be used a as the basic research for the study of D. punctiferalis.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.99-105
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• 2002

A gregarious pupal endoparasitoid Tetrastichsus sp. (Hymenoptera: Eulophidae) was reared in vitro from oviposition to adult emergence on an artificial host. The host pupal case was made using 0.02 mm-thick polypropylene film, and was filled with a diet consisting of powders of Antheraea pernyi pupa, chicken yolk, infant formula, royal jelly, and Neisenheimer's salt solution. Female parasitoids reared in the artificial host produced smaller sized progeny than those reared in in vivo, but the adults reproduced fertile offsprings. Furthermore in vitro second-generation (G$_2$) females showed more improved biological characteristics, compared with their parents. The fecundity (mean no. adult progeny), oviposition period (days), and longevity (days) of G$_2$ female were evaluated as 45.7, 7.8, and 13.8, respectively Female biased sex ratio was obtained with 76.9% female progeny. The results demonstrated that Tetrastichus sp. is a promising parasitoid for in vitro mass production.

• Korean journal of applied entomology
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• v.33 no.4
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• pp.281-285
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• 1994

This study was conducted to establish a nce insect pest control system, ~ es.ys tematic application of insecticides using carbohran and buproiezin, in Korea. The effects oi various dates of application and rates of buprofezin (25% WP) after carbofuran (3G) soil incorpombon in late May on the pop~~lation densities of the brown planthoppa (BPH) immigrating in July were investigated Appropriate application tune of buprofezin for the BPH that had evaded insecticidal effect of 5011 incorporated carbofuran was late July-early August. Application rate of buprofezln at 7.0g a.i/lOa was enough to suppress the BPH density. Buprofezin treatment after carbofumn soil incorporation could also suppress the whlte backed planthopper population but did not affect the densities oi the paddy rice spiders. Considering the charactenstics of occurring patterns of the nce insect pests in Korea. buprofezin treatment m late July or early August after carbofuran soil incorporation in late May can be a useful application system of ir~sectic~deins controlling early season Insect pests and migmtoly planthoppers on rice.

• Korean journal of applied entomology
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• v.4
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• pp.67-74
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• 1965

The work on the 'Studies of radiosensitivity' in Korea has been initiated since 1959 by the author at various institutions in home and foreign countries, and more than 20000 of plant materials in 73 varieties and 41 kinds are treated under varied conditions for the studies of radiosensitivity in plants. However, a study of the susceptibility to radiation in insect pests as well as their biological effects has not been previously reported in this country. During the year of 1964 and 1965, near 50000 of insects at the stages of adult, egg, larva and pupa in 14 different kinds are irradiated under acute X and gamma rays to investigate the behavior of growth and lethality after irradiation, and thrir general tolerances to radiations are compared by the kind of insects, stage of growth, radiation sources and exposured dosages. Through the experiments, it is shown that the lethality in most of insects are high as several kilo roentgens above and no significant effects on pupation. emergence, and oviposition in the treated generation at the dose of 3 Kr. below, but in the following generation , the rice stem borer for instance, no oviposition or decreased laying is observed from the dosages at 3 Kr. to 1 Kr., and the hatching was possible from 1.5 Kr. below of irradiated larvae although laying and hatching are seemed in normal. In general, the lethal dose $50\%$ of tested infect materials at the larval stage can he classified some what 60-80 Kr. for Pine caterpillar, Fall webworm, Camphor silk moth and their relatives, at 40-60 Kr. for Gypsy moth, Monley prominent and some relatives and at 20-30 Kr. for House fly, Rice weevil, Pine sawfly etc. Plant parasitic nematodes such as Hirschmannia and Paratylenchus shown very high resistance to radiation and the LD-50 is observed from 100 Kr. or above. A concept to evaluate the radiosensitivity in insects by taxological family line as a practical measure is not answerable yet, but it ran he solved within the near future through the continuing experiments.

• Korean journal of applied entomology
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• v.38 no.3
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• pp.225-230
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• 1999

This study was conducted to determine the effect of pupal development and adult longevity of Spodoptera litura larvae reared on leaves of different leguminos plants of 11 varieties or cultivars. Pupal duration varied from 8.7 to 9.5 days depending upon different diets and duration of female pupa (8.3~9.1 days) was about 1 day shorter than that of male's (9.4~10.1 days). Prepupal an postpupal duration were 1.7 to 2.0 days and 6.7 to 7.7 days, respectively. Pupal weight ranged from 0.23g to 0.43g for female and 0.24g to 0.35 g for male. Percent change of pupal weight was lowest (11%) on geomjeongkong-1 and highest (16%) on bukwangkong. Adult longevity was in ranging from 7.8 days on dongbu to 11.2 days on bukwangkong and tended to become slightly longer in female than tin male. Significant relationships were recognized between moisture content of feeding leaf, the pupal duration and weight and adult longevity.

• Korean journal of applied entomology
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• v.34 no.1
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• pp.65-69
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• 1995

This study was carried out to investigate the development and fecundity of Liriomyze chinensis under different temperatures. Egg periods were 4.5, 2.9 and 1.9 days, larval periods 12.7, 5.8, 4.5, days, pupal periods 20.1, 16.3 and 13.0 days, and total development periods from egg to adult emergence were 32.5, 25.0 and 19.4 days under 20, 25, $30^{\circ}C$ of constant temperatures, respectively. Based on this results, developmental threshold temperatures were calculated as 13.0, 11.0 and $7.2^{\circ}C$ and total effective temperatures as 33.0, 86.1 and 293.6 degree-days for egg, larva and pupa, respectively. seventy-eight% of the tested files emerged within four hours and a half after lighting, and none was emerged after eight hours and a half. The longevities of male and female were 5.0 and 8.5 days and the female fly laid 165.8 eggs with her life and punctured 983.8 stipples at $25^{\circ}C$.

• Korean journal of applied entomology
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• v.29 no.3
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• pp.165-169
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• 1990

A study was carried out to investigate some biological characteristics of Pseudogonatopus nudas, a nymphal parasitoid of the whitebacked planthopper (WBPH) under laboratory conditions (26-$28^{\circ}C$). Developmental periods of eggs, larva, prepupa and pupa were 2.5, 7.8, 2.7, and 14.2 days in average, respectively. Total developmental period from egg to adult emergence was average of 27.2 days. More than 83.5% of the wasps emerged in the morning between 6 and 10 o'clock, while very few emerged in the afternoon. The average longevity of female and male were 11.8 and 3.4 days when honey and WBPH nymphs were supplied as food. female laid an average of 25.3 eggs and the oviposition period was 5.4 days. The parasitoid seemed to prefer the 3rd instar nymphas as the host for oviposition with 68.8%, followed by the 2nd (19.6%), 4th (11.05) and 5th instar (0.6%). And no parasitism was recorded from the 1st instar nymphs and in adults.