• Journal of Sericultural and Entomological Science
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• v.43 no.1
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• pp.33-36
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• 2001

This study was carried out to improve the liquid culture methods of Paecilomyces japonica. The results show that the size of granular mycelium is smaller when the shaking speed is increased. Especially, the granular mycelium is the smallest at the shaking speed of 150rpm under the photoperiod of 12L-12D. Dry weight of mycelium was averagely 1.216 g in the Sikworm larva (SL) medium, and the weight was 2 times heavier than in the Potato dextrose (PD) medium. By adding 6 g of 6 mmbeads in the SL medium, the dry weight is increased to 1.332 g. The optimal addition of silkworm larval powder to the culture medium for gest harvest was 1.360$\pm$0.67 g in dry weight.

• Journal of Sericultural and Entomological Science
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• v.43 no.2
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• pp.83-87
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• 2001

This study was carried out to investigate the optimal medium and optimal dextrose concentration of 12 entomopathogenic fungi. The colonies of Cordyceps gracilioides, C. sp.(J23), Paecilomyces farinosus(J5), P tenuipes, Paecilomyces sp.(J4), Beauveria bassiana and B. brongniartii on SLA(silkworm larva agar) medium are similar to those on PDA(Potato dextrose agar) medium. On the contrary, the colonies of 5 fungi are very various according to its medium. The optimal medium for 1 1 fungi was SLA-A medium, which was better than PDA medium with regard to the mycelial growth. The optimal concentration on mycelial growth was superior to 6% for 6 fungi. When silkworm larvae was injected with P. tenuipes on SLA medium for fruiting body production. Infection rate, fruiting body formation rate, synnemata number and synnemata length were 91.3 $\pm$ 1.5%, 88.6 $\pm$ 2.3%, 56.6 $\pm$ 3.2 and 33.4 $\pm$ 2.88 ㎜ respectively. In economical analysis, the prototype medium can reduce 61.9% of production cost per 1 liter compared with PDA medium.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.169-174
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• 2008

The growth characteristics of Paecilomyces tenuipes according to the passage in the two kind of liquid media were investigated by comparing the mycelium and conidium formation degrees. The potato dextrose broth medium and the silkworm larvae medium containing the silkworm powder were used as the liquid media, and the potato dextrose agar medium and the brown rice medium containing the powder of silkworm pupa were used as the solid media. The conidium formation degree in liquid media differed by the passages but that in solid media was not. This suggested that the passage in liquid media did not affect significantly the conidium formation in solid media. When the brown rice media were inoculated with the concentration of $1{\times}10^{10}$ conidia/ml, $1{\times}10^8$ conidia/ml and $1{\times}10^6$ conidia/ml, respectively, the conidium formation degrees were similar. This indicated that the optimal inoculation concentration of conidium to the brown rice media is $1{\times}10^6$ conidia/ml.

• 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.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.138-139
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• 2003

To investigated the effect of liquid culture conditions and nutrient sources on the formation with bioactive substance of Paeilomyces japonica and Cordyceps militaris cultivated in the country, the result are as follow; The growth temperature of two mycelia is 25$^{\circ}C$ and the proper temperature for cordycepin growth is around 20$^{\circ}C$. The formation amount of bioactive substance by nutrient sources reached its peak with using 2% glucose and 1% galactose in case of carbon sources and 0.4% inorganic compound in case of nitrogen sources. Also, the ratio of C/N was optimal with 3% glucose 1% peptone. For a natural medium, most grains were sufficient but the soybean oil was superb. The formation amount of protein-binding polysaccharide that are used for anticancer substance was in proportion to the growth rate of mycelium, had lots of aeration and showed a trend of increasing when the acidity lower. and the content of structural protein showed a trend of increasing when the acidity lower. However, the content of the structural hexosamin did not get a great the effect of culture conditions and nutrient sources. The constitution of monosaccharide that organizes a protein-binding polysaccharide greatly changed in proportion to carbon sources. When Paecilomyces japonica cultured in a silkworm larvae for 30 days, the content of cordycepin was 204.5 mg/100mL as a dry weight in the fruiting body, 41.8 mg/100mL in mycelium and larva, and the content for each bottle was average 29.5 mg/100mL. In case of Cordyceps militaris for 45days, the fruiting body was 563.5 mg/100mL, the larva and the mycelium was 86.1 mg/100mL, and the content for each bottle was average 65.0 mg/100mL.

• Journal of Sericultural and Entomological Science
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• v.49 no.1
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• pp.28-32
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• 2007

This study was carried out to investigate the utilization of hemolymph of silkworm, Bombyx mori, as a substitute for fetal bovine serum(FBS) in the insect cell culture. Hemolymph is collected on a small scale by clipping the abdominal leg; however, this method is not appropriate for large scale collection. The hemolymph was collected from 5 th instar larva by centrifugation after cutting of the abdominal legs was more appropriate procedure for large scale collection. The cell growth in the medium supplemented with hemolymph(Baekokjam) collected in large scale was almost same as that in the medium hemolymph supplemented with hemolymph collected in small scale. However, the mutant($wE^b$) hemolymph collected in large scale was still less effective in the cell growth, as compared to the Baekokjam hemolymph collected in large scale. The optimum centrifugation condition for large-scale bleeding was 500 rpm and 15 min.

• International Journal of Industrial Entomology and Biomaterials
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• v.20 no.1
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• pp.29-35
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• 2010

To compare the quality of manufactured goods distributed in the domestic markets, 6 isolates of Dongchongxiacao products, namely, 4 Paecilomyces tenuipes specimens (J2P, 901A, 901B, and 901C), 1 Cordyceps militaris specimen (901D), and 1 Cordyceps sinensis specimen (CI-1), were analyzed for their physicochemical properties and sequence-structure relationships. P. tenuipes (J2P), a kind of Dongchongxiacao, was successfully inoculated on silkworms by percutaneous infection of Rural Development AdminstraionNam et al., 1999); fruiting bodies were then formed on the complete surface of the pupa. Since P. tenuipes (J2P) from silkworm larva was also proved to have remarkable pharmacological activities, it has been produced in bulk and has been successfully sold to buyers in the Korean market. Additionally, imitation products such as 901A, 901B, 901C, 901D, and CI-1 were sold simultaneously, resulting in deterioration of product quality. This research focuses on establishing quality standards to discriminate between the original and imitation products circulating in the market. The products obtained for the experiments included J2P, 901A, 901B, 901C, 901D, and CI-1; proximate analysis was performed for these products. The hosts and methods of conidia inoculation for proliferation of mycelia differed among the products. P. tenuipes (J2P) was proliferated in live silkworm larvae, and dead silkworm pupae were used to produce 901A, 901B, and 901C. On the other hand, 901D was produced on hulled rice medium. Quality analysis of C. sinensis revealed that CI-1, which was imported from China, smelled bad and proved to be a counterfeit with the fruiting body glued to the insect by twigs. The results of the proximate analysis of 901A, 901B, 901C, and 901D were similar to those of J2P with respect to the moisture content. Otherwise, J2P contained higher crude protein than 901A, 901B, 901C, and 901D, but contained very low fat. C. militaris (901D) and C. sinensis (CI-1) had low crude protein content-12.79% and 9.78% respectively-as compared to that of J2P, which was 62.38%. In contrast to the crude ash content of 6.4% in J2P, the crude ash content of CI-1 was 18.51% and this specimen was found to contain many impurities. phylogenetic analysis of P. tenuipes revealed that the sequence similarity of J2P, 901B, and 901C was in the range of 92.3~92.7%. Additionally, differences in the sequences were found at the positions 65 bp, 436 bp, 441 bp, 463 bp, etc.