• Korean journal of applied entomology
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• v.27 no.3
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• pp.149-158
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• 1988

Nematophagous fungi were successfully isolated by baited plating, centrifugation technique of soil, and direct isolation from naturally ingested nematodes. Predominant seven fungi isolated were identified as Artheobotrys arthroboteyides, A.conoides, A. oligospora, Dactylella lobata, Fusatium oxysporum, Monacrosporium ellopsoporum and Harposporium anguillu-lae. Of these, six fungi were tested for cultural characteristics except. H, anguillulae, extre-mely fastidious fungus in artificial media. Among 14 media tested in this experiment, Corn-meal Agar (CMA) and Oatmeal Agar (OMA) were the most suitable media for growing all six nematophagous fungi. Weakly saprophytic M. ellipsospoyum also grew vigoroualy on these two media. The radial growth, dry weight and sporulation of the fungi tested were quite diverse depending on the culture media. D. lobata revealed good growth and abundantly sporulated on Glucoes Peptone Agar (GPA). Although over-all growth of F, oxysporum was not satisfactory on Sucrose Nitrate Agar (SNA), the sporulation was best on this medium. Optimum conditious for mycelial growth and sporulation of nematophagous fungi ranged pH 5-8 and 20-$30^{\circ}C$ on SNA. D. lobata and F, oxysporum grew vigorously and most profusely sporulated on all media tested. They turned out an most promising biocontrol agents for their aggressive growth and sporulation over the ranges of temperature and pH ranges.

• Microbiology and Biotechnology Letters
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• v.32 no.2
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• pp.184-189
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• 2004

Rice wine cake (RWC) is the solid waste obtained after rice wine fermentation. For the mass production of the spores of yeast Saccharomyces from RWC, the optimum pretreatment condition of RWC, the optimum composition of culture medium, and the optimum culture condition were examined. For sporulation, yeast cells were grown in the pre sporulation medium (PSM), transferred into sporulation medium (SM) containing 1 % potassium acetate, and incubated in a rotary shaking incubator at $25^{\circ}C$ for 4 days. The supernatant of the mixture of RWC and water was used as the presporulation medium (PSM). The optimum temperature and time for the pre-incubation of the mixture of RWC and water (1:2) to obtain maximum sporulation yield were $V^{\circ}C$ and 24 hr, respectively, and optimum culture time in PSM was 48 hr. Using these optimum conditions, the asci number obtained was 0.72$ 1.06${\times}$10^{8}$$m\ell$. The addition of wheat coat koji into SM increased the final number of asci to beTEX>$10^{8}$ $m\ell$. Spores were formed in the SM with the initial pH of 7-11, but no spores were formed in the SM with the initial pH of 5. To save the time and effort to pretreat the RWC, 2% and 0.5% RWC without any pretreatment were directly added into PSM containing 1 % brown sugar and SM, respectively, and the maximum asci number of $1.27${\times}$10^{8}$ /$m\ell$ was obtained.

• The Korean Journal of Mycology
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• v.21 no.3
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• pp.224-229
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• 1993

The optimum temperature for germination of conidia and germ tube elongation were between $20\;and\;30^{\circ}C$ in C. dematium and C. gloeosporioides. Appressoria were fairly formed well at $20^{\circ}C$ despite the delay of conidial germination. At $30^{\circ}C$, both the germination and germ tube elongation are favored, but appressoria were poorly detected to be formed. In C. acutatum, the optimum temperature for germination of conidia was from $20\;to\;30^{\circ}C$, but at $25^{\circ}C$, germ tube elongation are accelerated. The conidia become septate and one or both doughter cells become conidiogenous instead of producing germ tubes and a secondary conidia produced, resulting in an arborescent type of connected conidia. Appressoria are infrequently formed by germinating conida. At $20\;to\;25^{\circ}C$ was the optimum for appressorium formation. But conidia that germinated at $30^{\circ}C$ seemed to lose the ability to form appressoria. The relation of temperature to germination of conidia and appressorium formation in Colletotrichum acutatum, C. dematium and C. gloeosporioides are discussed.

• Korean journal of applied entomology
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• v.11 no.1
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• pp.31-35
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• 1972

1. Continuous light induced more conidia than alternating light and darkness treatment in isolate Chinju 1. Isolate Suwon 3 produced much more conidia on synthetic medium than Chinju 1 in light. Conidial formation in Suwon 3 increased remarkably with alternate light and darkness in 8 days incubation. 2. Light was essential for perithecial formation in Chinju 1. No matured perithecia were observed in Suwon 3 with any treatment. Abundant perithecia were produced in Chinju 1 but only perithecial initiation occurred in Suwon 3. Suwon 3 produced significantly more conidia than Chinju 1, while perithecial formation was reversed. 3. Conidial numbers in soil decreased significantly through the winter at 10, 30 and 50 per cent soil moisture, with the most striking decrease at 10 per cent levels, but the number recovered again beginning in March, regardless of the soil moisture. The above results provide us a useful clue to support the possbility the conidia may serve as a primary inoculum.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1975.12a
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• pp.181.4-181
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• 1975

유포자 젖산균 Bacillus sp의 식품이용을 위한 기초로서 유포자 젖산균의 발육, 포자형성 등에 관하여 연구한 결과는 다음과 같다. 탄수화물 중 dextrin이 좋았고, Mn, Ca ion, biotin 등은 생육, 포자형성, 내열성에 대하여 효과가 좋았다. 배양의 최적조건은 호기조건하에서 $37~45^{\circ}C에서$ 36시간 이상 배양하는 것이었다.

• The Korean Journal of Mycology
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• v.25 no.4 s.83
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• pp.340-347
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• 1997

Conidia and cultural characteristics of isolates of chromogenic and teleomorphic strains of Colletotrichum gloeosporioides from apple and red pepper were compared. The mycelial growth of teleomorphic strains was faster than that of chromogenic strains in potato dextrose agar and V-8 agar. The chromogenic isolates from apple and red pepper developed. white gray to gray green mycelial rings interspersed with salmon to apricot colored conidial masses in colonies on potato dextrose agar and V-8 agar and none formed on ascigerous stage in cultures. The chromogenic isolates from red pepper produced conidia, most with one apex attenuated on apple and potato dextrose agar whereas fusiform and smaller conidia were produced in V-8 agar and water agar leaf medium. The chromogenic isolates from apple produced fusiform conidia in the media tested. The teleomorphic isolates from apple and red pepper produced cylindrical conidia, most with both apices rounded, developed white gray to dark olive green in a zonate pattern with small dark spots throughout colonies and formed the ascigerous stage in cultures.

• The Korean Journal of Mycology
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• v.12 no.4
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• pp.141-152
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• 1984

Aspergillus niger van Tieghem was cultured by the method of synchronous and submerged culture. Throughout the culture, sporulation was occured. Highly phosphorylated nucleotides in sporulating mycelia were detected to assure whether the eucaryotic Aspergillus niger produce these substances or not during the differentiation. Phosphorylated nucleotides were extracted from the conidiophore, bearing mycelia and spore forming body, these nucleotides were identified by TLC with P.E.I. cellulose. Guanosine tetraphosphate was found in both phialide forming mycelia and spore forming body. The contents of free amino acids were assayed and its level was found to increase at early stage of sporulation. The effects of 8-azaguanine examined, it was found to prevent spore formation and to made abnormal structure. The effects of inosinic monophosphate and guanosine monophosphate on spore formation were examined, spore formation was enhanced by these nucleotides.

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.99-103
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• 1984

Hyphal growth by Fusarium moniliforme was best at -14 bars osmotic water potential. Hyphal growth was prevented at -94 bars. The production of microconidia was best at -14 bars osmotic potential and prevented at -84 bars regardless of Strain. In contrast, this fungus sporulated macroconidia best at -1.4 bars and progressively less with each increment drop in water potential below that of basal media. The rate of spore germination followed a similar pattern with all of the spores; uniformly maximal at about -1.4 bars and progressively slower as the water potential was lowered from -1.4 bars to -42 bars. Under the natural conditions, plants infected by F. moniliforme produce microconidia on the dead tissues instead of producing macroconidia. This phenomenon agrees well with the water potential experiment since the dead plant tissues have a lower water potential than the living plant.

• Microbiology and Biotechnology Letters
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• v.17 no.1
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• pp.56-62
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• 1989

To find bacteria which can inhibit growth of enteropathogenic Clostridium perfringens ATCC 13124, spore forming butyric acid bacteria were isolated from 26 fecal samples of infants. Fourteen strains were found to be antagonistic to the enteropathogen and five of them produced butyric acid. A strain which produced the highest butyric acid was selected and identified as Clostridium butyricum. This organism sporulated in SM medium in 36 hours with optimum rates at 37$^{\circ}C$ and at pH 5.5. The spores tolerated well at high heat and acidity, and possible application of Clostridium butyricum as intestinal controller was discussed.

• The Korean Journal of Mycology
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• v.15 no.3
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• pp.149-157
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• 1987

This study was undertaken to investigate the differentiation, from spore germination to hyphae growth and phialide formation, of Aspergillus niger through the method of synchronous and submerged culture. Through continuous experiments by shake culture with potassium acetate medium, we observed the formation of spores at appropriate concentration and pH. Potassium acetate medium was set pH 5.5, 6.0, 6.5 and 7.0 on each scale, and control, 20 mM, and 40 mM, 80 mM and 160 mM concentrations on the other scale. Aspergillus niger was cultured in the defined media at $28^{\circ}C$, and mycelial dry weight, changes of pH and the onset of sporulation were checked. The mycelial dry weight, increased in potassium acetate medium, and pH increased during mycelial growth and gradually decreased after the spore formation. When pH increased excessively in Potassium acetate medium with pH 7.0, the mycelia could not adapt and mycelial dry weight decreased gradually. At pH 5.5, the onset of sporulation was done within one day at 20 mM it took, at 80 mM three days and at 160 mM concentration. in two days, at 40 mM one to four days were taken, 80 mM concentration respectively. At pH 6.5, the onset of sporulation was done in three days and four days at 80 mM concentrations respectively. Spore formation was not shown at pH 7.0. In controlled medium with all levels of pH, spore formation was not shown.