• Journal of Sericultural and Entomological Science
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• v.9
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• pp.49-66
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• 1969

Eri-silkworm is known as a tropical insect where as poly-voltine type in that area. It eats caster oil plant leaves which are cultivated as an every year cultivatable seed oil use in this country, even though it grows for many years in tropical countries. That is why, farmers have freedom for its cultivation in any year if they want. Therefore, eri-silkworm rearing service is flexible for its diet procurment as wish of farmer. The eri-cocoon price or economical fluctuation may be reactable for the rearing work not like as mulberry cocoon. Fortunately, it also eats cynthia tree leaves. Standing from such a easy condition, the authors have studied about this problem since 1963 to develope a culturing method of eri-silkworm rearing in this country and the authors brought out the matters to be produced as an industry scale. Here, the authors summarized their works of the results covering with thirty three work tables. The obtained results are as follows.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.724-729
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• 2016

Environmental factors that affect the singing of cicadas have not been studied extensively, especially those affecting the cicadas' singing during the nighttime. Therefore, the objective of this study is to identify the effects of tropical night and light pollution on the cicadas' singing in a downtown area. The study sites were an apartment complex in Seocho-gu, Seoul, and the Chiaksan National Park in Wonju-si. The study subjects were Hyalessa fuscata and Cryptotympana atrata, which are the dominant species in Korea during summer. Cicada songs were recorded 24 hours a day, every day. The recording period was between July and August, lasting 25 days at the Seoul site and 14 days at the Chiaksan National Park. Temperature, precipitation, humidity, and amount of sunshine were selected as the environmental factors that potentially affect the cicadas' singing. Statistical analyses included correlations of meteorological factors with the cicadas' singing per hour, per 24 hours, and at nighttime (21:00~04:00). The results showed that: 1) H. fuscata began singing during the dawn hours, and the singing increased in intensity early in the morning. C. atrata's singing reached its peak in the morning and afternoon, ceased during sunset hours, thereby exhibiting a difference in the singing pattern of the two species. 2) The frequency of singing by H. fuscata decreased when C. atrata began to sing intensively in numbers, thereby exhibiting interspecific influence. 3) The results of the correlation analysis between meteorological factors and the singing of H. fuscata and C. atrata showed that both species tended to sing more when the temperature was higher and sang less on rainy days. 4) When limited to nighttime only, C. atrata showed a tendency of singing when the nighttime temperature was high ($24-30^{\circ}C$, average $27^{\circ}C$), whereas H. fuscata did not show a correlation with meteorological factors. However, since H. fuscata sang during the night in areas with artificial lighting, it was concluded that its singing was due to light pollution.

• Korean journal of applied entomology
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• v.55 no.1
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• pp.17-26
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• 2016

Climate change has been regarded as one of main factors to change Korean insect pest fauna. Especially, a global warming model predicts to expand habitat for insect pests originated from tropical or subtropical regions. Two insect pests, the beet armyworm (Spodoptera exigua) and the diamondback moth (Plutella xylostella), are known to overwinter in some greenhouse conditions without diapause induction in Korea. There was a clear difference between these two insects in seasonal occurrence. P. xylostella occurred only at early spring and fall seasons, but did not occur during summer. In contrast, S. exigua maintained their occurrence from late spring to fall seasons. This study set up a hypothesis that the difference in the seasonal occurrence may be resulted from variation in susceptibility to high temperature. To test the hypothesis, heat tolerance was compared between these two insects. Exposure to $42^{\circ}C$ for 40 min killed 100% individuals of P. xylostella larvae. However, most larvae of S. exigua survived in response to $42^{\circ}C$ even for 80 min. Heat tolerance varied among developmental stages in both insects. Highest tolerant stages were $4^{th}$ instar larvae and adults for P. xylostella, but $1^{st}$ instar larvae for S. exigua. Pre-exposure to $37^{\circ}C$ for 30 min significantly increased heat tolerance in both insects. Induction of heat tolerance accompanied with significant increase of glycerol contents in the hemolymph in both insects and up-regulation of three heat shock protein expressions in S. exigua. These results suggest that the differential susceptibility to high temperature explains the disappearance of P. xylostella during summer, at which S. exigua maintains its occurrence.

• Korean Journal of Plant Resources
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• v.28 no.4
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• pp.382-390
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• 2015

Momordica charantia L. is a valuable food and medicinal plant of the gourd family (Cucurbitaceae) that is cultivated in tropical and subtropical regions of the world. Physicochemical properties of M. charantia based on cultivars, parts and growing stage were investigated. Crude protein contents of leaf were 27.5%, 26.9%, and 23.6% in native leaf (NL), cv. Erabu leaf (EL), and cv. Dragon leaf (DL), respectively. In particular, the crude protein content was the highest in leaves. The crude fat content was in the order of developmental stage 1 of cv. Erabu fruit (EF1) and developmental stage 1 of native fruit (NF1) with values of 4.0%, and 3.9%, respectively. There was also high amount of crude fiber in stem of all three cultivars. The crude ash content was in the order of cv. Erabu leaf, cv. Dragon leaf, and developmental stage 3 of native fruit (NF3) with values of 23.2%, 17.4%, and 13.6%, respectively. The major minerals found in M. charantia were K, Ca, and Mg. The potassium contents of developmental stage 3 of native fruit (NF3), developmental stage 3 of cv. Dragon fruit (DF3), cv. Dragon stem (DS), and developmental stage 2 of native fruit (NF2) were 498.37, 339.21, 314.30, and 307.34 ㎎ /100g, respectively, while the calcium contents were decreased of EL, DL, and NL with values of 513.45, 371.69, and 209.43 ㎎/100g, respectively. The calcium content was higher in leaves and stems than fruits. On the otherhand, the highest magnesium content was measured in EL (69.92 ㎎/100g). The highest contents of chlorophyll a, chlorophyll b, and total chlorophyll were found in NL (442.9 ㎎/100g dw), EL (759.6 ㎎/100g dw), and EL (1164.9 ㎎/100g dw), respectively. The vitamin C contents from developmental stage 2 of cv. Erabu fruit (EF2), NF3, developmental stage 3 of cv. Erabu on fruit (EF3), and NF2 were found with values of 2849.9, 2330.5, 1985.1, and 1844.5 ㎎/㎏, respectively, and found to be higher in Korean cultivar and Erabu fruit than in Dragon. The charantin contents of leaf were higher than the fruit found to be 547.71, 506.04 and 395.62 ㎍/g dw in DL, EL and EF2, respectively. According to the results, mineral contents, total chlorophyll and charantin contents of M. charantia were higher in the leaves (EL and DL) than the fruits. And, vitamin C content was the highest in the fruit (EF2 and EF3). Therefore, much more research needs to be undertaken to use of the leaves as well as fruits. The data showed that M. charantia can be considered a good source of nutrient for application in food system.

• Korean Journal of Soil Science and Fertilizer
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• v.7 no.1
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• pp.55-64
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• 1974

Effect of tow or three week potassium depression on nutrient contents in two rice varieties, Jinheung (a leading local) and IR 667-Suwon 214 (high yielding tropical line), was investigated at various growth stages in water culture system for the nutritional elucidation of potassium top dressing. According to potassium content, potassium ratio beween leaf blade and leaf sheath plus culm, relative potassium content ($-k/+k{\times}100$) and balance between potassium and other nutrients (K/N or K/Ca+Mg) it could be concluded as follows: 1) Rice plants have three sensitive growth stages to potassium stress in the orther of ear formation stage (20 to 30 days before heading) early tillering (15 to 25 days after transplanting) and at heading. 2) IR 667 is more sensitive to potassium stress than Jinheung, especially in early stage due to lower uptake of potassium. 3) Leaf sheath of IR 667 appears to have a role as potassium reservoir to greater extent than that of Jinheung.

• Korean Journal of Environment and Ecology
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• v.31 no.6
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• pp.564-577
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• 2017

We investigated whether external environmental factors acted as a trigger for flowering in the draft bamboo (Sasa borealis (Hack.) Makino) blooming area of Mt. Baekwoon located in Gwangyang, South Jeolla Province. We then considered the cause for flowering, flowering patterns and life history strategies of the draft bamboo based on the investigation. There were no differences in soil, physical conditions, and light amount between the draft bamboo flowering and non-flowering areas. The precipitation and temperature of the areas in Korea and Japan where it blossomed from 2014 to 2017 were similar to the normal year values (for the past 30 years). Moreover, most of the draft bamboo died after flowering on a large scale, but some did not, or some culms were developed again. In other words, the draft bamboo bloomed simultaneously regardless of external environmental factors, and most of the culms were dead, but some were left alive. Therefore, it is considered that the flowering is triggered by the specific genes (referred as to clock genes) expressed periodically by a biological clock rather than the external environmental factors. Meanwhile, the draft bamboos generally bloom on a large scale by synchronizing with other ones in the distance but may also bloom several times separately on a small scale. It may be a kind of an insurance system established to disperse the risk of failed sexual propagation when flowering once in a lifetime. The results reveal that the long-period monocarpy of the draft bamboo has been strengthened to optimize the sexual propagation to overcome the increased environmental instability caused by the expansion of distribution of tropical bamboos and bamboo species to the temperate regions.

• Journal of Life Science
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• v.28 no.9
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• pp.1068-1075
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• 2018

Kaempferia parviflora, an herbaceous plant in the family Zingiberaceae, is popular in many tropical regions. It is called as black ginger or krachaidum in Thailand and Laos, and its raw or dried root have been used as spices and teas. The rhizomes also have been traditionally used to treat gastrointestinal disorders, ulcers, gout, dysentery, allergies and to improve physical work capacity. Recently, its anti-obesity, anti-oxidant, anti-inflammatory and blood clot-lysis activities were reported. In this study, the anti-thrombosis activity of black ginger was investigated, since improvement in blood fluidity leads to the prevention of various lifestyle-related diseases. The hot water and ethanol extract and their subsequent solvent fractions (hexane, ethylacetate, butanol fractions and water residue) were prepared, and their anti-coagulation and platelet aggregation inhibitory activities were determined, respectively. Among the black ginger extracts and their fractions, the ethylacetate fraction (EAF) of ethanol extract only showed significant extensions of blood coagulation time determined by thrombin time (TT), prothrombin time (PT), and activated partial thromboplastin time (aPTT). At 5 mg/ml concentration, TT, PT and aPTT were extended to 1.22, 1.49 and >15-folds compared to non-treatment. The EAFs of ethanol and hot water extract showed strong inhibitions against collagen-induced platelet aggregations, which are comparable to inhibitions of aspirin. Also the EAFs from black ginger did not show any hemolysis activity against human RBC up to 0.5 mg/ml. Our results suggest that the EAF of black ginger has a potential as novel anti-coagulation and ant-platelet aggregation agent. This report provides the first evidence of anti-coagulation activity of black ginger.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.2
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• pp.214-219
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• 2008

An experiment was conducted to evaluate the effects of nitrogen (N) level on the dry matter (DM) yield, N concentration and oxalate content of some tropical grasses, namely Rhodesgrass (Chloris gayana), Guineagrass (Panicum maximum) and Sudangrass (Sorghum vulgare). Three levels of N as urea were applied (Standard- 260, $Standard{\times}2$- 540 and$Standard{\times}4$- 1,060 kg N/ha for Rhodesgrass; Standard- 380, $Standard{\times}2$- 770 and $Standard{\times}4$- 1,570 kg N/ha for Guineagrass and Sudangrass) in a completely randomized design and grasses were harvested twice at approximately two-month intervals. Dry matter yield tended to be higher with increased rate of N fertilizer in all species, while further additional N ($Standard{\times}2$ or $Standard{\times}4$) did not significantly (p>0.05) further increase DM yield, when compared with the Standard level of N fertilizer application. There was also a trend towards higher N concentration in plants as N fertilization increased in all species and it was increased significantly in Rhodesgrass and Sudangrass (p<0.05 or p<0.01, respectively). Further additional N ($Standard{\times}2$ or $Standard{\times}4$) application showed no significant (p>0.05) differences on oxalate content in plant tissue within species, when compared with the Standard level of N. The Rhodesgrass contained 0.11, 0.13 and 0.15% soluble oxalate and 0.23, 0.25 and 0.27% total oxalate with Standard, $Standard{\times}2$ and $Standard{\times}4$ level of N application, respectively. The Guineagrass contained 0.54, 0.50 and 0.42% soluble oxalate and 1.60, 1.56 and 1.45% total oxalate with Standard, $Standard{\times}2$ and $Standard{\times}4$ level of N application, respectively. The Sudangrass contained 0.06, 0.15 and 0.12% soluble oxalate and 0.22, 0.22 and 0.21% total oxalate with Standard, $Standard{\times}2$ and $Standard{\times}4$ level of N application, respectively The results from this study suggest that these grasses do not use further addition of N fertilizer ($Standard{\times}2$ or $Standard{\times}4$) to form high content of oxalate salts, when compared with the Standard level of N. In addition, the levels of oxalate present with these grasses are quite low as far as toxicity to animals is concerned.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.2
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• pp.208-217
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• 2018

Objective: Examine the effects of supplementing bahiagrass hay (BG) with potentially anthelmintic quantities of hays of perennial peanut (PEA) or sericea lespedeza (LES) or seeds of velvet bean (Mucuna pruriens L.; MUC) or papaya (PAP) on the intake and nutritive value (Experiment 1), and the performance and parasite burden (Experiment 2) of goats. Methods: In Experiment 1, 38 male goats ($27.4{\pm}5.7kg$ body weight) were randomly assigned to each of 5 treatments: i) BG alone and BG plus; ii) PEA; iii) LES; iv) MUC; and v) PAP. Goats were fed for ad libitum consumption and adapted to the diets for 14 d followed by 7 d of measurement. The PEA, LES, MUC (50%, 50%, and 10% of the diet dry matter [DM], respectively), and PAP (forced-fed at 10 g/d) were fed at rates that would elicit anthelmintic effects. In Experiment 2, goats remained in the same treatments but were allocated to 15 pens (3 pens per treatment) from d 22 to 63. All goats were infected with parasites by grazing an infected bahiagrass pasture from 0800 to 1500 h daily and then returned to the pens. Results: Dry matter intake tended to be greater in goats fed PEA and LES than those fed BG (757 and 745 vs 612 g/d, respectively). Digestibility of DM (59.5% vs 54.9%) and organic matter (60.8% vs 56.0%) were greater in goats fed MUC vs BG, respectively. In Experiment 2, feeding PAP, LES, and PEA to goats reduced nematode fecal egg counts by 72%, 52%, and 32%, reduced abomasal adult worm counts by 78%, 52%, and 42%, and decreased plasma haptoglobin concentrations by 42%, 40%, and 45% relative to feeding BG alone, respectively. Conclusion: Supplementation with PEA, LES, and PAP decreased the parasite burden of goats but did not increase their performance. PAP was the most effective anthelmintic supplement.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.5001-5007
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• 2014

The acetyltransferase inhibitor garcinol, a polyisoprenylated benzophenone, is extracted from the rind of the fruit of Garcinia indica, a plant found extensively in tropical regions. Anti-cancer activity has been suggested but there is no report on its action via inhibiting acetylation against cell proliferation, cell cycle progression, and apoptosis-inhibtion induced by estradiol ($E_2$) in human breast cancer MCF-7 cells. The main purposes of this study were to investigate the effects of the acetyltransferase inhibitor garcinol on cell proliferation, cell cycle progression and apoptosis inhibition in human breast cancer MCF-7 cells treated with estrogen, and to explore the significance of changes in acetylation levels in this process. We used a variety of techniques such as CCK-8 analysis of cell proliferation, FCM analysis of cell cycling and apoptosis, immunofluorescence analysis of NF-${\kappa}B$/p65 localization, and RT-PCR and Western blotting analysis of ac-H3, ac-H4, ac-p65, cyclin D1, Bcl-2 and Bcl-xl. We found that on treatment with garcinol in MCF-7 cells, $E_2$-induced proliferation was inhibited, cell cycle progression was arrested at G0/G1 phase, and the cell apoptosis rate was increased. Expression of ac-H3, ac-H4 and NF-${\kappa}B$/ac-p65 proteins in $E_2$-treated MCF-7 cells was increased, this being inhibited by garcinol but not ac-H4.The nuclear translocation of NF-${\kappa}B$/p65 in $E_2$-treated MCF-7 cells was also inhibited, along with cyclin D1, Bcl-2 and Bcl-xl in mRNA and protein expression levels. These results suggest that the effect of $E_2$ on promoting proliferation and inhibiting apoptosis is linked to hyperacetylation levels of histones and nonhistone NF-${\kappa}B$/p65 in MCF-7 cells. The acetyltransferase inhibitor garcinol plays an inhibitive role in MCF-7 cell proliferation promoted by $E_2$. Mechanisms are probably associated with decreasing ac-p65 protein expression level in the NF-${\kappa}B$ pathway, thus down-regulating the expression of cyclin D1, Bcl-2 and Bcl-xl.