• Journal of Sericultural and Entomological Science
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• v.28 no.2
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• pp.38-47
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• 1986

Silkworm(Bombix mori) were reared with modified artificial diets which were mixed with, as additives, leaf powders of Erigeron canadensis L., Cassia tora L., Cyperus anuricus Var.Laxus and Vigna Sinensis NEDL. The effects of additives on silkworm characteristisc of tested plants were summarized as follows ; 1. About 2-5% addition on dry weight base of leaf powders of E. canadensis, C. tora, C. anuricus or V.sinensis to the basic artificial diet promoted feeding response and digestion and resulted in good practical silkworm characteristics. The addition of V.sinensis and C.anuricus showed especially good effects. 2. The syneristic effect between different plant species was not recognized based on the feeding response and digestion of silkworm reared with various combinations of 2-4 different plant additives. 3. Electrophoretic zymograms of estrase, protease and phosphatase on haemolymph, intestine and silkgland were significantly different among treatments. In general, 1 or 2 more electrophoretic bands were detected when feeding response and digestion were promoted. 4. Contents of starch, crude fat, crude protein and inorganic base were apparently higher in the tested plants than in mulberry leaves. However, no volatile ingredent which is directly realted with feeding response was identified.

• Journal of Sericultural and Entomological Science
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• v.17 no.1
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• pp.63-68
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• 1975

Flacherie of all other silkworm diseases greatly affects cocoon crop as it is far-reaching and wide spreading. Fleacherie which kills silkworms caused by bacteria can be classified as bacterial digestive organ disease, and "Sotto" disease. Bacterial digestive organ disease is caused by the bacteria living in the silkworms alementary canal and a majority of flacherie belongs to this disease. Septicemia is caused by bacterias breeding in silkworms body fluid but its attach is comparatively limited during the larva period. "Sotto" disease is caused by eating mulberry leaves infected with bacteria which produce toxin and silkworms are intoxicated and killed by the toxin. The cause of flacherie is mainly due to a poor environment. The unclean and unsanitary silkworm rearing beds help bacterias breeding and bacteria enter silkworms body through mouth organ or skin. The present study is to investigate various causes of flacherie by means of pulverization of silkworm. Filtrated fluid is extracted by centrifuge and hypodermic of peroral inoculation-is given to young and medium silkworms of spring and autumn. The gained results of the experiment are summarized as follows： 1. Silkworms infected with flacherie were pulverized and their filtrated fluid was extracted by centrifuge and inspected under microscope to find polyhedron from the fluid. 2. The experimenting group of peroral inoculation. a) From the third day of peroral inoculation silkworms appetite generally decreased and ate less compared with the control group. b) After 7 days of the inoculation silkworms suffered from empty head, loose bowels and fainting. c) Some of the silkworms still ate but as were shown in Fig. 3 and 4 some dwarfish silkworms were found. d) There was no remarkable difference between 1st and 2nd instar inoculation groups. e) There was a tendency that the number of diseased silkworms was decerased as the increase of instars. 2. The experimental group of hypodermic inoculation a) Both of 3rd and 4th instar inoculation groups showed no remarkable singularity and the number of diseased silkworms decreased. b) The rate of diseased silkworms was comparatively low because the body fluid was acidy or toxin was hard soluble. Hypodermic inoculation could not give much harm to the silkworms compared to peroral inoculation.

• Journal of Korean Society of Forest Science
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• v.96 no.6
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• pp.737-741
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• 2007

Typical phytoplasma witches' broom symptoms were observed in black locust (Robinia pseudoacacia L.) in Korea. The symptoms of the disease were showing abnormally small leaves, shortened intemodes and proliferation of shoots. The phytoplasmas were detected consistently in all the symptomatic samples by the amplification with phytoplasma universal primer pairs P1/P7 and R16F2n/R2, and the expected size was 1.8 kb and 1.2 kb. However, the phytoplasma DNA was not detected in healthy seedling. Based on sequence analysis of amplified region, this phytoplasma has close homologies with aster yellow, mulberry dwarf, maize bushy stunt, ash witches' broom and sumac witches' broom phytoplasmas, more than 99.2% but showed homologies with black locust witches' broom (GeneBank Accession No. AF 244363), and jujube witches' broom, 88.6% and 87.7%, respectively. This phylogetic analysis indicates that the black locust witches' broom phytoplasma founded in korea should be classified in the Candidatus phytoplasma asteris (16Sr I) group and clearly distinct from the black locust witches' broom group 16Sr III (peach X-disease phytoplasma group).

• Korean Journal of Environmental Agriculture
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• v.20 no.2
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• pp.99-107
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• 2001

PCBs(Polychlorinated biphenyls) in air and plants were measured every two weeks at Hankyong University located in Ansung, Kyoung ki province from July to November in 1999. The percentage of tri-CBs(PCB 28) and tetra-CBs(PCB 52) is 49% of the total PCBs in air, which shows these two components are the major congeners. A correlation coefficient(r) of PCB congeners detected in two plants is 0.83 (p<0.01), indicating that the plants can be used as a passive sampler to indirectly estimate the pollution levels of residual PCBs in the environmental even if they have different physicochemical properties. The average ratio of PCB 110/PCB 52 is higher in plants as 0.5, 2.9 and 2.5 respectively in the air and mulberry leaves as well as scallions, which comes from the higher lipophilicity of PCB 110 rather than the ratio of PCB 110/PCB 52 in the air.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.6
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• pp.607-613
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• 2014

In a previous study, we have shown that mulberry leaves (Mori Folium) extract MFE) and its compounds have the antioxidant effect in human red blood cells. However, the possible effect of MFE and its compounds on improvement of blood flow were not reported. Therefore, the aim of this study is to investigate the effects of MFE and its compounds on improvement of blood flow in a rat model of topical ferric chloride ($FeCl_3$)-induced carotid artery damage. The $FeCl_3$ treatment seriously damaged the carotid artery: the walls of the artery, blood flow rate, blood vessel diameter, blood vessel area and blood flow amount. However, administration of MFE or its compound has ameliorated the blood flow and suppressed thrombus in blood vessels. Moreover, the concentrations of serum total cholesterol, triglycerides, and LDL cholesterol in the MET and its compound groups were remarkably reduced in comparison to the control group, and HDL cholesterol concentration was higher in the MET and its compound groups than in the control group. These results suggest that MFE and its compounds ameliorate the thrombosis against blood vessel damage.

• Journal of Sericultural and Entomological Science
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• v.14 no.1
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• pp.25-35
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• 1972

This investigation was carried out to find the effects of silkworm rearing technique on the harvesting amounts. In spring and autumn of 1971, 14 silkworm rearing farmers at Botong Ri and Youngsoo Ri, Chongnam Myun, Hwaseung Kun, Kyunggi Do in Korea were selected as sample farmers. They were devided into two groups, high productivity group and low productivity group according to their harvesting amounts per box of silkworm eggs in 1970. The high productivity group represents the farmer who produced above average harvesting amounts per box, and the low group represents below average group. In this investigation, all farmers were adjusted to share uniform rearing condition with even mulberry leaves. Under this uniform condition, the effects of rearing techniques on the harvesting amounts per box of silkworm eggs and the effects of rearing condition on the harvesting amounts were inferred. Results obtained are as fellows; (1) Measuring from the 14 sample farmers, the effect of rearing technique on the harvesting amounts per box covers 15% of farmers in spring rearing season but 33% in autumn season. (2) Measuring from these sample farmers, the effects of the nutrition condition is less than 56% in spring rearing season but less than 69% in autumn, and it can be concluded that these effects include the effect of climate factor. (3) In the low productivity group. the most important facto. affecting the low productivity is non-disinfection of rearing environment.

• Journal of Digital Convergence
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• v.16 no.12
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• pp.593-602
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• 2018

The purpose of this study was to investigate the coloring properties of non-mordant dyes by examining local literature on silk fabric dyeing using red-colored natural dyes. Natural dyes can be prepared from the following 8 materials: purple-fleshed sweet potato, Impatiens balsamina, mulberry, fruits of Ligustrum japonicum Thunb, guava leaves, dansam, hibiscus flowers, and pruned branches of Prunus persica. To examine the surface color calculated $L^*$, $a^*$, $b^*$, ${\Delta}E^*$, and K/S value and H V/C. The variables considered in the dyeing experiment were dye concentration, dyeing temperature, dyeing time, and number of dyeing iterations, which were varied to evaluate the dyeing properties and color characteristics. As a result, the abovementioned variables, dye affinity, and red color expression were directly proportional to one another. In this study, it was found that red coloring can be obtained with natural dyes; moreover, excellent dyeing was achieved without the need for repeated dyeing or mordanting processes, which cause environmental pollution.

• International Journal of Industrial Entomology and Biomaterials
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• v.45 no.1
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• pp.22-28
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• 2022

Silkworms are very sensitive to changes in temperature and humidity, and unless it is a suitable temperature and humidity to grow, the productivity and quality of silkworms are greatly reduced. Therefore, it is very important to manage temperature and humidity for silkworm feeding facilities. In particular, it is essential to install heating facilities in Asian countries with distinct seasonal changes. During the feeding period, many farms manage the temperature and humidity of feeding facilities by installing and using electric heaters inside the facilities. However, it is very difficult to manage the room temperature stably by the heaters. In addition, unlike the temperature inside the facility, silkworms could undergo severe temperature changes as the inside of the rearing tray could not be warm enough. In this study, in order to improve the previous heating method, the new rearing method that directly heats the bottom of the rearing tray was developed. Compared to the previous room-heating system, the novel heater-installed tray (HIT) system significantly reduced the change in temperature during the experimental period. In addition, the number of days of silkworm growth up to harvest was shortened, which was effective in growth performance, and it was also found that silkworms grew more uniformly in HIT system than in previous system. Moreover, as the heater tubes were installed directly under the rearing tray, it quickly dried mulberry leaves and silkworm feces after feeding, and as a result, the environment in the tray was greatly improved with decrease the labor of breeder. In conclusion, these results suggest that the heater-installed rearing tray method greatly improves silkworm quality, increases weight of silkworms, and final profits compared to the previous room heating system with electric heaters.

• Journal of Sericultural and Entomological Science
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• v.17 no.2
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• pp.133-139
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• 1975

For developing the therapeutic agents to be administered orally for treating certain silkworm diseases and applying them to clinical conditions, vehicles suitable for the agents are needed. The author presumed that Lactose, Casein, and Urea, respectively, have an effectiveness as the vehicle. A series of experiments were carried out on these substances for conforming the applicability of the vehicles at the silkworm rearing house of the College of Agriculture, at Seoul National University during the spring silkworm rearing season of 1974 and the spring and autumn seasons of 1975. The author recognized, Lactose, Casein, and Urea, when put on the mulberry leaves in a powdered form, are eaten along with the leaves by silkworm. Thus, the systemic administration of them to silkworms are possible. The author administered these individual substances orally to silkworm larvae in doses of l0mg., 30mg., 50mg., and 100mg. per gram of the body weight of the silkworm larvae at intervals of once a day, once every two days, and once every three days for 15 days. This was carried out from the first day of the fourth instar to just before mounting. The influences of these substances on the growth of silkworm larvae and the cocoons made by the larvae were observed. The author found out after completing the experiment that Lactose had no effect on growth and cocoon formation. This was observed in all cases. Casein inhibited the growth of silkworms except in the case of administered doses of once every third day in whick the growth and the cocoons were normal but the administration of the agent brought considerably large numbers of abnormal cocoons in every case. Urea inhibited both the growth and the formation of tile cocoons in most cases. For the confirmation of the clinical effectiveness as the vehicles for some therapeutic agents, the three substances, Lactose, Casein, and Urea, will be investigated more closely for the mixing amounts needed and other pertinent data.

• Journal of Sericultural and Entomological Science
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• v.15 no.1
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• pp.15-25
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• 1973

The author studied the applicability of Furazolidone to the silkworm rearing industry as a useful remedy for certain silkworm diseases, at the silkworm rearing house of the college of agriculture, Seoul national university, during both the spring and the autumn silkworm rearing season of 1972. Discovering the fact that Furazolidone, when put on the mulberry leaves in a powdered form, is eaten along with the leaves by silkworms and thus the systematic administration of Furazolidone to silkworms is possible, the experimenter carried on a series of experiments (1. determining the in vitro antibacterial activity of Furazolidone to four pathogens of silkworm diseases-Bacillus thuringiensis, Aspergillus oryzae, Aspergillus flavus, and Isaria farinosa, 2. observing the prophylactic and therapeutic effect of Furazolidone against the experimental flacherie caused by inoculation of B. thuringiensis, and 3. examining the toxicity of Furazolidone to silkworm larvae). As the results of the experiments the investigator found out the fundamental fact that Furazolidone exerts a good prophylactic and therapeutic effect against flacherie which is the most common and important silkworm disease: Furazolidone, in in vitro test, inhibited completely the growth of B. thuringiensis, the pathogen of bacterial flacherie, at the concentration of 1 ${\mu}$g/mι. with the tube method and at the concentration of 5 ${\mu}$g/mι. with the plate method, and the drug showed an excellent prophylactic effect and a considerably good therapeutic effect, depending on the time of administration, on the 5th instar silkworms inoculated B. thuringiensis, at the tentative dose of 150mg. per 10 silkworms administered once a day for 2 days. For the practical administration of Furazolidone against flacherie, the dose, the time and duration of administration, and the form of preparation, will be investigated more closely.