• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.134-139
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• 2012

Inhibition effects on spore germination and mycelia growth for gray mold (Botrytis cinerea) were investigated in vitro using environment-friendly agricultural materials as well as environment-friendly pesticides. The inhibition effect on mycelia growth of gray mold is the highest when the gray mold mycelia were treated with a pesticide (commercial name: Koreayeok, Jihabudea KM, Sootingtan, Sootingstar) that contains a mixture of Bacillus subtilis, resulting in 100% inhibition of the mycelia growth. Meanwhile, the range of less than 20% inhibition effects on the growth of gray mold mycelia was observed with other commercial agricultural materials. The significant inhibition effects on spore germination of gray mold fungus were shown in vitro with two water dispersible pesticides containing sulfur [BTB (97.7%) and SulfurStar (92.3%)], respectively. These in vitro results of inhibiting of the spore germination and mycelia growth together cannot found. It remains to be determined whether the selected environment-friendly agricultural materials in effective control of gray mold in vitro can be used to control gray mold in field.

• The Korean Journal of Pesticide Science
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• v.10 no.3
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• pp.201-209
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• 2006

Antifungal activities of 43 different plant oils were evaluated against different phytopathogenic fungi. Thyme oil showed highest antifungal activity among the tested oils. The major of thyme oil were found to be thymol, carvacrol, bomeol, p-cymene and linalool. Thymol and carvacrol were found to be responsible for thyme's antifungal activity. The spore germination assay was conducted on Alternaria mail and Botrytis cinerea. Thymol and carvacrol strongly inhibited spore germination in the fungi test. In addition, thymol and carvacrol showed a curative effectiveness to gray mold disease on cucumber crop. The antifungal activities of alkylphenol and alkylaniline compounds, which has similar molecular structure to that of thymol or cavacrol, were also tested. It was found that alkylphenol compounds also show higher inhibition to spore germination. Thus, thymol, carvacrol and alkylphenol compounds can be used an potent antifungal agents.

• International Journal of Industrial Entomology and Biomaterials
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• v.23 no.1
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• pp.107-113
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• 2011

Infection effect of $Nosema$ $bombyics$ on the midgut of silkworm $Bombyx$ $mori$ and subsequent appearance of spores and the performance of larvae was studied. Autopsy of larvae showed white pustules on the surface of midgut at 5 days of post infection (pi). At later stage, important organs like midgut, silk gland and gonads reduced in size and all these organs showed white pustules. Light microscope observation of pustules revealed enormous spores. Spore multiplication was at a faster rate in young larvae. Infection of the adult larvae resulted in pebrinized pupa and moths. Larval weight, cocoon weight and cocoon shell ratio reduced as the post infection period increased. Transverse sections of midgut showed $N.$ $bombycis$ infection limited to a few columnar cells at 3-5 days of pi. At 7 days pi, cell volume increased, cells were swollen and elongated. Heavily infected cells looked like sacks filled with parasite and the apical region of certain cells were bulging into the gut lumen. Later at 8-9 days of pi, spores or its developing stages leaked into the lumen either freely or enclosed within the globules of host cytoplasm. Besides columnar cells, development of $N.$ $bombycis$ was observed in the regenerative cells and rarely in goblet cells. Development of $N.$ $bombycis$ was also observed in both longitudinal and circular muscles at the late pi period. The histopathological changes, deformities and spore production time in the host were all influenced by the spore dosage and age of the host.

• The Korean Journal of Mycology
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• v.13 no.2
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• pp.115-121
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• 1985

An aerial survey for fungal flora in Seoul has been carried out by Petri plate exposure method for a period of one year. A total of 2227 fungal spores appeared in the plates. Of these, Cladosporium was the commonest fungus representing 43.5% of the total spore count followed by Penicillium (15.8%). Alternaria (10.5%), and Aspergillus (3.8%). There were seasonal variations in the prevalence of fungal spores. The occurrence of these fungi was greatly affected by climatic conditions. However, Alternaria appeared to prefer warmer weather. A comparison of fungal population from the outdoor and indoor air was also investigated to support the view that Alternaria is abundant population from the outdoor air and that Cladosporium from the indoor air depending on their availability in the atmosphere.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.46-58
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• 2017

This study was conducted to investigate the optimal conditions for spore germination, prothallus propagation, sporophyte formation and seedling growth in Microlepia strigosa (Thunb.) C. Presl. Spore germination and prothallus development were promoted by low concentrations of Knop medium nutrient solution. The optimal medium for prothallus propagation and antheridium formation was 2X MS medium with 3% sucrose. The activated charcoal content of the medium did not affect prothallus proliferation. Among the various combinations of culture soil (bedding soil, peat moss, perlite and decomposed granite), a mixture of bedding soil, peat moss and decomposed granite at a ratio of 1 : 1 : 1 (v : v : v) had a positive effect on sporophyte formation. The most efficient conditions for promoting the growth of whole plants (sporophyte seedlings) were 50 - cell plug trays filled with a mixture of bedding soil and decomposed granite at a 2 : 1 (v : v) ratio.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.336-342
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• 2009

To confirm the antimicobial mechanism of Torilis japonica, antimicrobial profile was observed on various spore conditions by combining 0.1% (3 mM) torilin with antimicrobial activity and 0.27% water fraction with germinants. A 75% ethanol extract of T. japonica fruit reduced Bacillus subtilis ATCC 6633 spore counts by 3 log cycles and reduced the vegetative cells to undetectable level (by about 6 log cycles) (both in terms of CFU/mL). Further fractionating the ethanol extract into n-hexane and water fractions revealed that the former reduced the spore count by 1 log cycle whereas the latter had no effect. The antimicrobial active compound was isolated and purified from the hexane layer, and identified as torilin ($C_{22}H_{32}O_5$). The water fraction of the ethanol layer did not show antimicrobial activity, whereas the antimicrobial effect of 0.1% (3 mM) torilin was significantly enhanced in the presence of the water fraction (0.27%). This result can be explained by synergistic effects of the water fraction containing considerable amounts of germinants such as L-alanine and K+ ions that triggered germination.

• Journal of Life Science
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• v.11 no.5
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• pp.432-438
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• 2001

Various lactic acid bacteria were isolated from Korean Dongchimi (whole radish Kimichi with added water) in order to study their antimutagenic activity. Ames test using Salmonella enterica serovar typhimurium TA98 and TA100 showed the strain DLAB19 to have the highest antimutagenic activity among the 300 isolated strains against MNNG(N-methyl-N-nitro-N-nitrosoguanidine), NPD (4-nitro-O-phenylenediamine), 4-NQO(4-nitroquinoline-1-oxide) and AFB$_{1}$(aflatoxin B$_{1}$). The strain was identified as Leuconostoc mesenteroides subsp. cremoris according to the Bergeys Mannual Systematic Bscteriology based on its morphological, cultural, physiological characteristics and biological system Antimutagenic activity of Leu. mesenteroides subsp. cremoris DLAB19 was found in the culture supernatant suggesting the bacterium secretes, the antimutagenic substance in the media. The antimutagenic activity of Leu. mesenteroides subsp. cremoris DLAB19 was reconfirmed by the spore-rec assay using spores of Bacillus subtilis H17 (Rec$^{+}$) and M45 (Rec$^{[-10]}$ ).).

• Journal of Aquaculture
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• v.16 no.1
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• pp.44-50
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• 2003

This study aimed to develop the methods of growing Enteromorpha prolifera natural seedlings in its natural habitat and artificial indoor seedlings by inducing spore release. Likewise, the study examined the possibility of mass production by developing cultivation techniques with cultivating examination. The natural seedling of E.prolifera thrived in a sea area composed of sand and mud, which Is its natural habitat. Growing of this alga on the seedling frame 20 cm high from the bottom at the intertidal zone in summer and 40 cm high in fall was found to be very effective. However, enabling the best attachment rate for artificial indoor seedling requires inducing spore release after drying the mature thalli in a dark place fur about 12∼24 hours and setting seedling nets in a dark water tank (spore solution) for 24 hours. Breeding E.prolifera in a pole-system farm is best done in shallow sea areas with mud or mud and sand geological feature. However, floating-system lam is better for deep-sea areas with fast current. Ideal farming places are sea areas with plenty of nutritional salt and safe places that protect the lam facilities against billows. Furthermore, an exposure method on seawater surface to produce larger output should be used.

• Korean Journal of Microbiology
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• v.33 no.1
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• pp.7-14
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• 1997

This study was to elucidate the relation between the periodical requirement of growth factors(Yang et al., 1993) and the synthesis of RNA and protein during the germination of Streptomycn coefic%r A3(2) in mineral liquid medium(ISP-4) without addition of growth factors. As results, The germination time was about 10 hr, and meanwhile, periodical nutritional requirement was verified to be repeated with interval of 2 hr. Spore size was enlarged with time but its number was rather decreased. Spore could be deviJed into viable, dormant, and dead state. In such a germination process it was found that RNA and protein were being synthesized periodically when spores were stained with AO and INT methods and observed under the fluorescence microscope. Those syntheses were coincided with the period of nutritional requirement. Hence, it was discllssed that spore population in early germination would need amino acids related to protein synthesis.

• International Journal of Industrial Entomology and Biomaterials
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• v.27 no.2
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• pp.282-288
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• 2013

In nature, the population of Nosema bombycis (Microsporidia) causing pebrine disease is small and their development is extremely slow and only few ultimately producing spores. Pebrine infected silkworm, Bombyx mori larvae collected from sericulture field were alive till $3^{rd}$ generation though the concentration of N.bombycis spore was very high ($2.4-3.0{\times}10^8$ spores. $mL^{-1}$). All larvae were died during $4^{th}$ generation with extremely high concentration of pebrine spores ($3.0-4.0{\times}10^9$ spores. $mL^{-1}$) and mostly contain long polar tube (LT). Alternately, all larvae were died immediately (at $3^{rd}$ stage of $1^{st}$ generation) when it was artificially inoculated with same concentration of N.bombycis spores harvested from field ($2.4-3.0{\times}10^8$ spores. $mL^{-1}$) though concentration of spores harvest was very less ($3.0-4.0{\times}10^6$ spores. $mL^{-1}$) and mostly contain short polar tube (ST). Artificially pebrine infected male moth when mated with healthy female moth took six generations to develop pebrine disease and all larvae were died at the $2^{nd}$ stage with very less spore harvest ($3.0-10.0{\times}10^6$ spores. $mL^{-1}$). Survival percentage was increased in all generations (~92.0% at $4^{th}$ generation) when silkworm rearing was conducted under new integrated disease management system.