• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.902-908
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• 2010

In 2008, we monitored residual pesticides of 15 agricultural products such as rice, corn, pea, chestnut, mandarin, lemon, onion, pineapple, lettuce, chard, sweet potato stalk, burdock, squash, sweet pepper and mushroom. Agricultural commodities were collected from markets in 22 provinces (Seoul, Busan, Incheon, Daegu, Ulsan, Daejeon, Gwangju, Wonju, Pohang, Gumi, Changwon, Gimhae, Suwon, Seongnam, Bucheon, Goyang, Yongin, Cheongju, Cheonan, Jeonju, Yeosu, and Jeju). Total 48 pesticides were analysed by multi-residue method using GC/MS/MS. We analysed 1,064 samples and 34 samples (3.20%) were detected. Sweet potatostalk, burdock, chestnuts, peas, corn, chard, squash, mushroom and onions were found to be free from pesticide residues. 6 other agricultural products did not exceed MRLs (Maximum Residue Limits) by the Korean Food Code. Chloropyrifos and fenobucarb were particularly prevalent and also they were detected over 10 times in this monitoring. Nonetheless, the exposed quantity of the 7 residual pesticides is to be considered relatively safe, compared with the acceptable daily intake (ADI) of residual pesticides.

• The Korean Journal of Mycology
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• v.9 no.1
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• pp.7-12
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• 1981

Attempts were made to investigate the effects of the temperature and carbon dioxide concentration in the growing room and soil moisture after casing on the mycelial growth, sporophore formation and mushroom yield of Agaricus bisporus (Lange) Sing. The growing room temperature influenced the mycelial growth in the casing layer after casing and the sporophore formation of Agaricus bisporus. The mycelial growth was the rapidest at $30^{\circ}C$ and gradually decreased with the temperature going down, while the sporophore formation and mushroom yield were the best at $25^{\circ}C$. The other factor which affected the mycelial growth and sporophore formation was the moisture content of casing soil. The mycelial growth was the best at 70 percent moisture, and the sporophore formation and mushroom yields were the highest at 60 percent moisture. The concentration of carbon dioxide in the growing room after casing had an important effect upon the mycelial growth in the casing layer and the sporophore formation. When the concentration of carbon dioxide was 0.16 percent, the mycelial growth and the sporophore formation were not inhibited. At 0.5 to 2.0 percent $CO_{2}$ the myceilal growth and the sporophore formation were severely decreased. The sporophore size of the mushroom was the maximum when the room temperature during the vegetative mycelium growth was $20^{\circ}C$ and the moisture content of casing soil was 70 percent.

• The Korean Journal of Mycology
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• v.9 no.3
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• pp.117-122
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• 1981

A tunnel system of mushroom cultivation was designed to compare with the conventional cultivation method in Korea. The bed and air temperature during the phase II the tunnel system was more stably controlled than in the conventional house. The indipensable energy was much saved in the tunnel system than in the conventional method, as this system did not require additional heat supply in the phase II. Compost fermented in the tunnel was proved to contain higher total nitrogen and moisture than compost in the conventional house. Residual ammonia content of compost fermented in the tunnel did not exceed 300ppm. Mushlroom mycelial growth in the tunnel was as good as in conventional house. The tunnel system did not require additional heat supply during mycelial growth period. Mushroom yield and quality from the tunnel system was 5 per cent higher and better than that of the conventional method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.236-241
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• 1997

Inhibitory effects of several edible plant extracts against 3-hydroxy-3-methylglutaryl coenzyme A(HMG-CoA) reductase, a rate-limiting enzyme in the biosynthesis of cholesterol, were screened. Inhibition rates of $10{\sim}15%$ were observed with hot water extracts of Allium fistulosum, Allium sativum and Cucurbita maxima. Methanol extracts of Aster scaber, Allium sativum, Zingiber officinale, Oenanthe javanica and Angelica keiskei effectively reduced the enzyme activity with inhibition rates of $29{\sim}51%$. The methanol extract of Angelica keiskei was fractionated sequentially with chloroform, ethyl acetate and n-butanol. Of the fractions ethyl acetate fraction showed the highest inhibition against the enzyme. $Luteolin-7-O-{\beta}-D-glucoside$ and hyperoside isolated from the ethyl acetate fraction of Angelica keiskei inhibited the enzyme activity by 65.5% and 14.8%, respectively, at the concentration of $30{\mu}M$.

• Research in Plant Disease
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• v.12 no.3
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• pp.254-259
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• 2006

Bacillus spp. isolated from mushroom medium wastes were evaluated for their biocontrol potentials on control of Sclerotinia rot of lettuce. The Bacillus isolates were more effectively obtained from waste suspension when directly added into nutrient agar(NA) medium than plating on the agar medium. Totally 42 isolates obtained from the wastes B23 and B42 showed highest antifungal activity against eight fungal pathogens such as Sclerotinia sclerotiorum, Rhizoctonia solani, Pythium ultimum, Phytophthora capsici, Fusarium oxysporum, Colletotrichum gloeosporioides, Cladosporium cucumerinum, and Botrytis cinerea and B23 and B42 were finally selected for further studies. Optimal concentration of the isolates was $10ml(10^7cfu/ml)$ to suppress the Sclerotinia rot of lettuce. Supplements such as starch, glycerol, and egg-yolk successfully maintained the bacterial population for 30 days in vitro and increased bio-control potentials against the disease. The bacterial isolate B23 alone showed 72% control value, furthermore it presented 95% control value when supplemented with 0.2% of starch, glycerol, and egg-yolk. The promising Bacillus isolates B23 and B42 were identified as Brevibacillus brevis and Bacillus stearothermophillus, respectively, based on morphological and physiological characteristics according to API database.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.2
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• pp.80-88
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• 2013

The present study was conducted to evaluate relationship between nonylphenol uptake rate and clearance rate of Ruditapes philippinarum, Corbicula japonica and Mytilus edulis. Variation of the temperature and body size of the bivalves was used to modulate clearance rate and nonylphenol uptake rate in this experiment. Clearance rate and nonylphenol uptake rate experiments were determined for two different size classes of the bivalves (R. philippinarum: 0.35, 0.73 g, C. japonica : 0.047, 0.1000g, M. edulis: 0.30, 0.37 g; mean flesh dry weight) and three different temperature regime (5, 13 and $18^{\circ}C$). Weight-specific clearance rate in all animal size and temperature ranges increased in the order of R. philippinarum, C. japonica and M. edulis. The weight-specific nonylphenol uptake rate did not show specific trend among species. The clearance rate and nonylphenol uptake rate generally decreased with animal size and increased with water temperature. For all three species nonylphenol uptake rate had a strong relationship with clearance rate. For a given clearance rate ranges, the nonylphenol uptake rate was in the order of R. philippinarum > C. japonica > M. edulis. The results suggest that water ventilation capacity of filter-feeding organisms is an important physiological factor controlling uptake rate of dissolved nonylphenol.

• Journal of Mushroom
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• v.16 no.1
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• pp.57-60
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• 2018

Agricultural sticky traps are used for forecasting flying insects, including fungus gnat adults. Forecasting using sticky trap is an important measure to determine pesticides or environmentally friendly control means. Sticky traps of various colors can be installed easily and quickly. The yellow sticky trap is most effective for forecasting fungus gnat adults. In addition, they are used for control purposes by mass trapping. We tested the optimum installation height of yellow sticky traps to forecast and control the fungus gnat adults effectively in the cultivation of mushroom and horticultural plants. The number of captured fungus gnat adults was highest on the second floor for button mushroom and oyster mushroom, 100 cm above the floor for sawdust shiitake mushroom, 20 cm under the floor for hydroponic strawberry, and 20 cm above the floor for hydroponic tomato. This suggests that sticky trap height should be installed differently depending on the cultivation type or environment for effective forecasting and control of fungus gnat adults.

• Journal of Mushroom
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• v.16 no.1
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• pp.45-50
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• 2018

This study was performed to compare medium characteristics during the composting stage for medium turning performed using an excavator agitator and a prototype medium turner in button mushroom cultivation. The changes in temperature in the medium did not significantly differ between the treatments until the 3rd turn performed using the excavator agitator. However, during the 4th and 5th turns, the temperature increased during turning with the prototype medium turner. During outdoor composting, various types of microorganisms such as thermophilic bacteria (Bacillus spp.), Actinomycetes, fluorescent Pseudomonas spp., and filamentous fungi were found to be distributed in the medium. The counts of aerobic bacteria and fluorescent Pseudomonas spp. did not significantly differ between treatments, and the counts of thermophilic bacteria and thermophilic actinomycetes were slightly higher during turning with the prototype medium turner. The rice straw was slightly shorter and water content lower for the prototype medium turner. There was no significant difference between pH and EC treatments. The L, a, and b values tended to increase on turning with the prototype medium turner.

• Journal of Mushroom
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• v.18 no.3
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• pp.274-279
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• 2020

This study was conducted to investigate the characteristics of the medium used on the composting step, comparing the excavator agitator with the self-propelled turner. The temperature of the outdoor composting medium tended to increase rapidly after flipping in the turner. The late composting medium temperature was maintained at the excavator treatment area (farm practice), and the late composting effect progressed. During the field composting stage, various microorganisms such as Bacillus spp., Actinomycetes, fluorescent Pseudomonas spp., and filamentous fungi were distributed in the medium, and the density of aerobic bacteria involved in the decomposition of the medium was increased. Under high-temperature composting conditions, blue fungi, and mesophilic actinomycetes were inhibited or killed. Thermophilic actinomycetes, which play an important role in decomposing organic matter, showed higher densities than those observed in farm practices in the self-propelled turner process. The length of rice straw was slightly shorter when the self-propelled turner was used, and the water content did not show any significant difference between treatments. The a and b values tended to increase as the inverter was turned over. The CN ratio of the composting broth was lowered from 23.1 to 16.2 for the 5th turnover in the context of farming practices, and from 23.3 to 16.9 in the context of the self-propelled turner. The yield of each treatment was increased by 20% in 1 period, 28% in 2 periods, and 26% in 3 periods; the overall yield was 23%.

• Korean Journal of Microbiology
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• v.36 no.1
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• pp.33-39
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• 2000

Some of thermophilic fungi which has growth-promoting effect on Pleurotus ostreatus were isolated from compost during high temperature fermentation process. The temperature optima of 7 isolated thermophilic fungi were $50^{\circ}C$ on PDA media. Isolated strains S-1 and S-2 have the best mycelial growing rate, so these isolates were expected as excellent thermophilic fungi for high temperature composting and mycelial growing of oyster mushroom. In liquid culture, the optimal pH of thermophilic fungi observed variously, pH 7.0-10.0 but most of thermophilic fungi grow well in pH 8.0-pH 9.0 and the final pH of media after cultured was done pH 5.5-6.0. In liquid culture of thermophilic fungi on the optimal condition, S-2 have the best mycelial growing rate. The growing rate of thermophilic fungi S-1, S-2, S-5, and S-10 on lignocellulosic substrates was good but Humicola grisea var. thermoidea, well know thermophilic fungi which has growth-promoting effect on Agaricus bisporus, was poor and which was well grown on PDA at $50^{\circ}C$, pH 7.0. Isolated strain S-1 was identified as Trichophyton sp. and other 6 strains were identified as Sepedonium sp. by morphological characteristics.