• The Korean Journal of Mycology
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• v.31 no.1
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• pp.8-13
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• 2003

The fruiting body of Paecilomyces sinclairii was collected in Baekyangsa, Jeollanam-Do, Korea. Cultural conditions for the mycelial growth and fruiting body formation were investigated. Its optimum mycelial growth was obtained at 25℃ and pH 8 on potato dextrose agar and Hamada media among the various media tested. The carbon and nitrogen sources for the optimum mycelial growth were dextrin and glutamine, respectively. The optimum C/N ratio was about 20:1 in case that 1% glucose was supplemented to the basal medium as a carbon source. The favorable mycelial growth was obtained from corn meal extract medium mixed with 30% (w/v) milk solution. The maximum fruiting body was formed in unpolished rice medium supplemented with 20% (w/w) silkworm pupae at $25^{\circ}C$ under 500lux.

• Journal of Sericultural and Entomological Science
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• v.15 no.2
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• pp.9-14
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• 1973

In order to find out effects of the generative power of silk worm moth which have been brought up in the high temperature accommodation at their pupa stage. For this specific study, 9 different kinds of male silk worms have been selected as specimen. All those specimen were brought up in the normal temperature at their larvae stage and after the pupation period they have been accommodated in the condition of high temperature for a certain length in accordance with the study programme. Afterwards, those mlae specimen were copulated with Suwon jam 103${\times}$104 which were all brought up in normal conditions. This study was carried out to find the copulation function as well as the ratio of unfertilized eggs(male sterility test). Results of study have been revealed as follows: 1) Although some differences were observed, male pura which have been brought up in the condition of high temperature shown the low rate of unfertilized eggs rather than those were brought up in the normal conpition. 2) In this group the eclosion(emergency) has been found to be poor rather, than those specimen brought up in normal conditions. 3) The copulation function of Moran, Daedong, J124 and C108 specimen were found to be poor than those of Suwon jam. 4) Fertility rate of Moran, Daedong, J124 and C108 was found to be around 65%. This figure is rather lower than what we normally expect. 5) Unfertilized egg ratio of Moran, Daedong and C108 were found to be around 20% if they were brought up in the condition of high temperature for one day from the time of pupation: 40% at 2 days, and 70% at 3 days duration. More than 3 days treatment has shown no progress in the unfertilized egg ratio. 6) One day's treatment for the pupa at the later stage has shown the unfertilized egg ratio of about 10%; 20% at 2 day's treatment, 35% at 3 day's treatment, 40-60% at 4 day's treatment, more than 60% at 5 day's treatment, and the 70% of fertilized egg ratio was only observed when the treatment days come to 7 days. It was understood that the unfertilized egg ratio was high at the antepupa stage rather than that of post-pupa stage. 7) According to the result of observation the sperm in copulatory pouch and seminal receptacle out of the normal female silk worm which have been copulated with the male brought up in the condition of high temperature at their moth stage. The reproduction system found in the control zone has been found to be normal and the sperm is amountful and active in motion while the sperm found in the treatment to be limited in amount and slow in motion. The observation was made within 5 hours from the copulation. 8) According to the result of observation of sperm of seminal receptacles of the female silkworm moth, and according to that observation of sperm in the seminal receptacle in female silkworm moth, the amount of sperm and mobility in the female moth brought up in high temperature were poor comparing that were brought up in normal temperature zone. Some of them are even found to be no trace of such. 9) Appearance and mosle of the copulatory organ of the male silkworm moth was found to be no anatomical change. 10) Testis of the later pupa stage which was brought up in the high temperature was found to be almost net developed to anucleate sperm and they are degenerated at stage of between maturation division and sperm abnormal stage. Mean time at control zone, the formation of anucleate sperm was already observed.

• 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.

• The Korean Journal of Mycology
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• v.25 no.3 s.82
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• pp.209-218
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• 1997

This study was carried out to obtain the basic data for artificial culture of Grifola umbellata. The optimal condition for the mycelial growth was obtained at $20^{\circ}C$ and pH 4, respectively. G. umbellata showed the most favorable growth on the Hoppkins media. Carbon sources such as glucose, fluctose and manitol were favorable for stimulating a mycelial growth of G. umbellata. Valine, one of nitrogen sources also appeared to be favorable to a mycelial growth. The optimum C/N ratio was about 30:1 in case that 1% glucose as carbon source was mixed with the basal media. Lactic acid as organic acid was most favorable to the mycelial growth. Also, thiamine-Hcl as vitamin source was favorable. The mineral nutrient of $FeSO_4$ or $MgSO_4$ was most favorable to G. umbellata, and its optimal concentration was about 0.01% in $FeSO_4$ and 0.1 % in $MgSO_4$ respectively. Among 4 different cereal extract media, polished rice extract medium which was mixed with silkworm pupae was most suitable for a favorable growth of G. umbellata.

• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.321-330
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• 1999

Nematodes were isolated using silkwom trap through the investigation of 100 soil samples from various biotopes in Korea. The 30 nematode strains from soil and dead insects by the pathogenicity aganinst silkworms (Bombyx mori mori) and insect pests of Calliphora vomitoria, Pseufazetia separata, Palomena angulosa, and Melolontha incana. Mortailty of the silkworm larvae and pupae were as high as 100% by nematode infection, those of insect of pests were varied from 20 to 100%. The 30 strains of entemopathogenic nematodes were classified into five groups of Rhabditidae, Diplogatroidae, Heterorhabitidae, Steinernematidae, and Tylenchida by morphological criteria. The genetic relationships among the 30 nematode strains were analyzed by various RAPD bands with twenty primers. The 30 nematode strains were classified into six major subgroups on the basis of the genetic similarity coefficient of 0.853. The grouping by RAPD was agree with those of morphological taxa in discrimination of the higher group, however, was not completely agree in the subgroup. The family Steinernematidae belong to Rhabditida was clarified as closer to the Tylenchida, rather than the other Rhabditida of Heterorhabitidae, Rhabditidae, and Diplogatroidae in genetic distance valule. From the result of the morphological classification and RAPD of the genomic DNA showed that genetic relationship analysis furnish infurmation on phylogenetic classification and relationships of entomopathogenic nematodes. The application of genetic similarity will overcome the limitation of taxonomy and classification of morphologically simple nematode. Several primers were confirmed those utility of identification for individual nematode strains, the methods of molecular genetics secured the simplicity, rapidity and accuracy on the selection of entomopathogenic nematodes.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.317-324
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• 2020

In order to create the national food nutrient database, a total of 41 animal foods (ham, seafood, edible insects and eggs) were analyzed for their vitamin B₁₂ content and the applied immunoaffinity-HPLC was verified. Ham vitamin B₁₂ contents were 0.30-0.65 ㎍/100 g. Seafood showed relatively high vitamin B₁₂ level, where the values of fermented clam were the highest (26.80 ㎍/100 g) followed by fermented pollack roe. Vitamin B₁₂ was not detected in silkworm pupae and beetles, while relatively high levels were found in the two-spotted cricket imago (6.70 ㎍/100 g). Chicken and quail egg yolk had roughly 100- and 30-times higher vitamin B₁₂ levels as compared to their egg white. Vitamin B₁₂ contents in quail and chicken eggs were significantly enhanced by boiling (p<0.05). Results based on accuracy (97-102% recovery) and precision (<5% RSD) indicate that this study provides reliable vitamin B₁₂ information on animal foods consumed in Korea.