• The Korean Journal of Mycology
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• v.21 no.1
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• pp.38-50
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• 1993

Four plant (Sorghum bicolor, Cassia mimosoides var. nomame, Sesamum indicum and Glycine soja) were cultivated at the pots including the soils containing arbuscular mycorrhizal fungi and were also investigated with the colonizations and productions of arbuscular mycorrhizal fungi. Whereas the colonizations of arbuscular mycorrhizal fungi continuosly increased on the roots until 50 days, the productions of arbuscular mycorrhizal fungal spores were fluctuated with the terms of 30 days after inoculated. This indicated that the colonizations on the roots were not correlated with productions of arbuscular mycorrhizal fungal spores. Also, the various soils collected were applied to this technique by using pot cultures. Out of 82 various soils collected, the spore productions of arbuscular mycorrhiaze were observed only from 42 soils. The spores cultured under artificial conditions were identified to 15 species with four genera. The spore productions of arbuscular mycorrhizal fungi using this technique would be considered to be related to the soil pH: The spore productions were found in the low pH for the species of Acaulospora and Glomus, the those near pH 7.6 for the species of some Glomus, Scutellospora and Gigaspora.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.172-183
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• 1994

The productions of arbuscular mycorrhizal fungal(AMF) spores were observed by adding three different commercial fertilizers on AMF inhabiting soils. Various morphological features, vesicles, arbuscles, sporulations of spore, and flower-like-structures, were also found in the mycorrhizal roots during 80 days after transplanting. Spore prodcutions of the employed AMF were observed to be periodically increased with the intervals of 40 days. Sorghum, green onion, hot pepper, and wild legume plants were appeared to be a good plant for productions of AMF and as the host of AMF. The productions of AMF spores was inversely related to phosphate fertilizer, and also observed to be low in the plant pots added with whole balanced fertilizers.

• Journal of Life Science
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• v.12 no.1
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• pp.43-48
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• 2002

An actinomycetes which produces fibrinolytic enzyme was isolated from soil. Characteristics of the isolated strain and the optimal conditions for the productions of fibrinolytic enzyme were summarized as follows; The fibrinolytic enzyme production strain generates gray airmycelium and had about 0.6~0.8$\times$0.4~0.8${\mu}{\textrm}{m}$ cylindrical spore, smooth surface and formed spore chain of 10~40 spores. We have identified this strain as Streptomyces sp. JK-20. This strain was able to grow up at 20~32$^{\circ}C$ and its optimum growth temperature and pH was 24$^{\circ}C$ and pH 6.0, respectively. The optimal conditions for porducing fibrinolytic enzyme; carbon source, nitrogen source, metal ions and phosphorous sources was 1% xylose, 0.5% yeast extract, 0.5% polypepton, 0.1% MgSO$_4$.7$H_2O$ and 0.1% NaH$_2$PO$_4$.2$H_2O$, respectively. This strain showed the highest productivity of fibrinolytic enzyme after the fourth day under such optimal culture conditions.

• Journal of Microbiology
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• v.42 no.1
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• pp.60-63
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• 2004

A sucrose-agar globule (SAG) was newly introduced to increase production of the vesicular arbuscular mycorrhizal (VAM) fungal spores, Gigaspora gigantea and Glomus fasciculatum. An SAG inoculum and a sucrose-agar globule with root exudates (SAGE) inoculum were prepared, and their spore productions were compared with a soil inoculum. When the SAGE was used as the inoculum on sucrose-agar medium plates the number of spores was increased (35% more than the soil inoculum). After the soil inoculum and SAGE were inoculated on an experimental plant, Zingiber officinale, the percentage root colonization, number of VAM spores, and dry matter content were analyzed. It was observed that the SAGE showed a higher percentage of root colonization (about 10% more), and increases in the number of spores (about 26%) and dry matter (more than 13%) for the two VAM fungal spores than the soil inoculum. The results of this study suggested that the SAGE inoculum may be useful for the mass production of VAM fungi and also for the large scale production of VAM fungal fertilizer.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.369-372
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• 1998

Microbial insecticide formulations were prepared by liquid and semi-solid fermentations using Bacillus thuringiensis subsp. kurstaki, HL-106 (BTK-HL106), B. thuringiensis subsp. israelensis HL-63 (BTI-HL63) and B. sphaericus 1593 (BS-1593) strains. The liquid fermentation medium contained molasses 2%, dextrose 1.5%, peptone 2%, D-xylose 0.025%, CaCl$_2$ 0.1%, K$_2$HPO$_4$ 0.1%, KH$_2$PO$_4$ 0.1%, MgSO$_4$$.$7H$_2$O 0.03%, FeSO$_4$$.$7H$_2$O 0.002%, ZnSO$_4$$.$7H$_2$O 0.02%. The composition of the semi-solid fermentation medium was rice bran 45.2%, zeolite 31%, yeast powder 0.02%, corn powder 5%, dextrose 3%, lime 0.3%, NaCl 0.06%, CaCl$_2$ 0.02%, and H$_2$O 15.42%. Insecticide formulations produced in the liquid fermentation named BTK-HL106, BTI-HL63 and BS-1593 pesticides and those in the semi-solid fermentation were designated as BTK-HL106-1, BTI-HL63-1 and BS-1593-1 pesticides, respectively. The number of spore (endotoxin crystals) was 2.65${\times}$10$\^$9/ spores per $m\ell$ in the BTK-HL106 and 3.5${\times}$10$\^$10/ in the BTK-HL106-1 3.8${\times}$10$\^$9/ spores in the BTI-HL63 and 7.0${\times}$10$\^$10/ in the BTI-HL63-1, and 7.5${\times}$10$\^$9/ in the BS-1593 and 1.4${\times}$10$\^$10/ in the BS-1593-1. The spores in the BS-1593 formulation was produced two times more than the other formulations. The spores in the BTI-HL63-1 were contained twice than those in the BTK-HL106-1, and five times than those in the BS-1593-1. The results indicated that spore (endotoxin crystals) productions in the semi-solid fermentation increased about ten times than those in the liquid fermentations. $LC_{50}$s of the BTI-HL63 and BS-1593 were 4.5 $\mu\textrm{g}$, and those of the BTI-HL63-1 and BS-1593-1 were 1.5 $\mu\textrm{g}$. $LC_{50}$ of the BTK-HL106 was 1.5 mg and that of the BTK-HL106-1 was 0.9 mg. The $LC_{50}$s of the formulations in the semi-solid fermentations showed about two to three times higher than those in the liquid fermentations.