• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.428-434
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• 2013

An isolate of Bacillus amyloliquefaciens subsp. plantarum CC110 was selected as an effective antagonist for biological control of cucumber downy mildew caused by Pseudoperonospora cubensis. Temperature range for growth of CC110 isolate was $7.5{\sim}55.0^{\circ}C$, and its optimal temperature at $36.6^{\circ}C$. pH range for growth of CC110 isolate was 4.5~9.5, and its optimal pH at 7.0. In this study, the most effective sources of carbon and nitrogen for growth of CC110 isolate were fructose and yeast extract, respectively. The volatile of CC110 isolate was found to be effective to control downy mildew on cucumber showing no diseased area whereas that of control was 13.2% using the I plate bioassay. The culture broth and cells of isolate CC110 cultured in TSB media for 48 hours at $28^{\circ}C$ inhibited occurrence of cucumber downy mildew. The cells and culture broth were transformed into sporangia of P. cubensis by in observation under light microscope and scanning electron microscope.

• Journal of Life Science
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• v.28 no.8
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• pp.923-930
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• 2018

In this study, Tenebrio molitor (T. molitor) was fermented with Lactobacillus plantarum JBMI F3 (F3), Lactobacillus plantarum JBMI F5 (F5), Lactobacillus gasseri Ba9 (Ba9), Aspergillus kawachii KCCM 32819 (Ak), Saccharomyces cerevisiae KACC 93023 (Sc), and Bacillus subtilis KACC 91157 (Bs). After fermentation, the fermented products were extracted by water, ethanol, and methanol, and their physicochemical and biological properties were investigated. In a DPPH assay, the water extracts of the fermented products of T. molitor showed high antioxidant ability. Among the water extracts, the fermented product by Bs showed the highest DPPH radical scavenging activity. The total contents of phenolic compounds and flavonoids were highest in the fermented products by Ak and Bs, respectively. Reducing activity was detected the most high activity on ethanol extract of fermented product by Bs. The water extract of the fermented product by Bs exhibited strong enzymatic activity for fibrinogen and starch hydrolysis. Based on the observed physicochemical and biological properties, the fermented products of T. molitor by microorgansims can likely be applied as functional materials in various industries.

• KSBB Journal
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• v.24 no.6
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• pp.508-514
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• 2009

This study investigated the production of catalase from Bul-kyo soil bacteria through fermentation process. Isolation and selection of bacteria was performed through chemical and physiological analysis. Catalases were produced from bacteria which belong to 3 different species (Bacillaceae bacterium BKBChE-1, Bacillus sp. BKBChE-2, Bacillus flexus BKBChE-3) confirmed by using 16S rDNA sequence method. The catalases were found to be stable in the temperature range of $30^{\circ}C-60^{\circ}C$ for BKBChE-1, BKBChE-2 and BKBChE-3 and also in the pH range of 9.0-12.0 for BKBChE-1 and BKBChE-3. Long-term stability of the catalases was about 20 days at $4^{\circ}C$. However, BKBChE-2 has kept its activity over 30 days at $4^{\circ}C$.

• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.59-67
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• 2018

This study was conducted to isolate the cellulolytic bacteria able to grow on LB- Carboxymethyl cellulose (CMC) agar trypan blue medium from the mixed forest and Larix leptolepis stands. Three bacterial strains with high activity against both CMC and xylan were isolated. Both API kit test and 16S rRNA gene sequence analysis revealed that the three different isolates belong to the gene Bacillus. Therefore, the isolates named as Bacillus sp. EFL1, Bacillus sp. EFL2, and Bacillus sp. EFP3. The optimum growth temperature of Bacillus sp. EFL1, EFL2, and EFP3 were $37^{\circ}C$. The optimum temperature for CMCase and xylanase from Bacillus sp. EFL1 were $50^{\circ}C$. The optimum pH of Bacillus sp. EFL1 xylanase was pH 5.0 but the optimum pH of CMCase from Bacillus sp. EFL1 was pH 6.0. The optimum temperature of CMCase and xylanase from Bacillus sp. EFL2 was $60^{\circ}C$, respectively. The optimum pH of CMCase of Bacillus sp. EFL2 was 5.0, whereas xylanase showed high activity at pH 3.0-9.0. The optimum temperature for CMCase and xylanase of Bacillus sp. EFP3 was $50^{\circ}C$. The optimum pH for CMCase and xylanse was 5.0 and 4.0, respectively. CMCases from Bacillus sp. EFL1, EFL2, and EFP3 were thermally unstable. Although xylanase from Bacillus sp. EFL1 and EFP3 showed to be thermally unstable, xylanase from Bacillus sp. EFL2 showed to be thermally stable. Therefore, Bacillus sp. EFL2 has great potential for animal feed, biofuels, and food industry applications.

• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.375-379
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• 2016

This study investigated the decomposing activities on gelatin and egg sac of root-knot nematode (Meloidogyne incognita). Ten Bacillus isolates (KRB-1~10) isolated from the soils of Mt. Naejang. Among them, KRB-5, 9, and 10 showed decomposing activities, and identified as Bacillus subtilis KRB-5, Bacillus amyloliquefaciens KRB-9, and KRB-10 by 16S rRNA sequence analysis, respectively. Under pot experiments using pepper, 100-fold diluted culture broth of three isolates reduced the number of egg sac on roots collected 60 days and 90 days and increased the growth of aerial part compared with the group only treated with Meloidogyne incognita. Especially, the group treated B. subtilis KRB-5 was superior in the growth of pepper. These results suggest that the B. subtilis KRB-5 can be used to control the root-knot nematode on pepper.

• Horticultural Science & Technology
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• v.19 no.3
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• pp.384-388
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• 2001

The selenium (Se) contents of 20 herbs, harvested in three areas in Korea, were analyzed. Many herbs had no Se. Angelica ($138.4{\mu}g \;Se{\cdot}kg^{-1}$ FW), caraway ($167.8{\mu}g \;Se{\cdot}kg^{-1}$ FW), chamomile ($116.6{\mu}g \;Se{\cdot}kg^{-1}$ FW), marjoram (158.7 and $132.6{\mu}g\;Se{\cdot}kg^{-1}$ FW), and oregano ($62.5{\mu}g\;Se{\cdot}kg^{-1}$ FW) accumulated Se as higher concentration compared with other plants. The Se content of herbs was dependent on the species, cultivars and areas. The status of Se uptake by herbs was investigated according to Se concentrations in hydroponics. During four weeks, before harvest of several herbs in greenhouse, sodium selenate ($Na_2SeO_4$) was added to the nutrient solution at concentrations of 2, 4, 6, and $8mg{\cdot}L^{-1}$. Field-mint accumulated Se too high, but external symptom of Se toxicity was not found. Essential oil content was generally proportionated to treated-Se concentration. The essential oil contents in basil and balm increased two to three times higher by sodium selenate treatment compared to non-treatment, but they did not show any linear relationship between essential oil contents and treated-Se concentration.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.69-74
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• 2002

This study was conducted to investigate the milk quality produced from dairy farms in Jeju province and to analyze the variety of pathogenes and the number of somatic cells in the milk. Data were collected from 262 lactating cows from 8 farms of three regions and the results obtained are summarized as follows. 1. The average daily milk yields and milk fat contents from June and October were 22.3 kg and 3.7%, respectively. 2. The average number of bacterial counts in raw milk was 1.5${\times}10^4$/ml, but that in farm A was over 3.0${\times}10^4$/ml. 3. The somatic cell counts were 2.5${\times}10^5$/ml in average and those in farm G and H were higher than those in other farms. Their distribution in 262 lactating cows from June to October was as follows; less than 2.0${\times}10^4$ /ml in 68.8% of cows, 2.0-5.0${\times}10^4$/ml in 18.8% of cows and more than 5.0${\times}10^4$/ml in 12.4% of cows. 4. Of the 113 isolates (compartments of cow udder) from mastitic milk, Staphylococcus aureus was found in 47, Streptococcus ogalatiae in 17 and Bacillus in 12. 5. The average monthly income of the farmers was 407 thousand won/head, and that in farm A or E was higher than that of farm H (456-475 thousand won vs. 314 thousand won) In conclusion, to improve income dairy farmers should reduce the somatic cell counts in the milk and mastitis infection through regular disinfection and inspection.

• Microbiology and Biotechnology Letters
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• v.45 no.3
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• pp.218-225
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• 2017

Saeu (shrimp) jeotgal (SJ) was prepared by mixing with 25% salt with different types: purified salt (PS), solar salt aged for 1 year (SS), and bamboo salt. SJ was fermented for 22 weeks at $15^{\circ}C$. Bacilli and marine bacteria were detected throughout the entire fermentation period, and marine bacteria were present in the largest numbers. Lactic acid bacteria (LAB) were detected only during the first 8-10 weeks, but yeasts appeared at the sixth week and later. Archaea were detected in low numbers only from SS-SJ during the first 8 weeks. BS- SJ showed higher pH and lower titratable acidity (TA) values than other SJs because of strong alkalinity of bamboo salt. Amino-type nitrogen (ANN) contents of SJs increased during fermentation, especially, after 2 and 6 weeks. SS-SJ showed the highest ANN content from the beginning to the end of fermentation. Ammonia-type nitrogen (AMN) contents also increased like the amino-type nitrogen during fermentation. The highest volatile basic nitrogen (VBN) was also observed in SS-SJ. Salinity was kept constant after 4 weeks. SS was better than other salts for SJ fermentation in terms of protein hydrolysis.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.242-247
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• 2011

Soil management for environment-friendly agriculture depends on the effects of soil microbial activities and soil fertility. To improve soil health for the upland crops, this study evaluated a relationship between soil chemical properties and soil microbial diversities at 25 sites in upland soils in Gyeongnam Province. The average nutrients in the upland soils were 1.7 times for available phosphorous, 1.4 times for exchangeable potassium and 1.5 times for exchangeable calcium higher compared to recommend concentrations in the upland soils. We found a significant positive correlation between the soil organic matter and the soil microbial biomass C (p<0.01). Contents of organic matter and dehydrogenase in the inclined piedmont soils were significantly higher than those in the other topographical soils (p<0.05). In addition, concentrations of organic matter and microbial biomass C in the loam soils were significantly higher than in the silt loam soils (p<0.05). In principal component analyses of chemical properties and microbial populations in the upland soils, our findings suggested that available phosphorous should be considered as potential factor responsible for the clear upland soils differentiation. The soil organic matter was positive correlation with Bacillus sp. and fungi, whereas soil pH was also positive correlation with Pseudomonas sp. in upland soils.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.1035-1040
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• 2016

This study investigated the prevalence of foodborne pathogens and the bacterial community of traditional Doenjang collected from a longevity area in Korea as well as the antagonistic effect of traditional Doenjang isolates against Bacillus cereus to estimate the microbiological safety of traditional Doenjang. Aerobic bacteria showed $10^6{\sim}10^9CFU/g$, whereas coliform bacteria was not detected. Foodborne pathogens were not detected except B. cereus, which was detected in seven samples out of 10 Doenjang samples. A total of 327 isolates were identified from traditional Doenjang. The isolates consisted of Bacillus subtilis 155 (47.4%), Bacillus licheniformis 68 (20.8%), Bacillus amyloliquefaciens 46 (14.1%), and Bacillus pumilus 18 (5.5%). Antagonistic effect against B. cereus was detected in 20 (6.1%) of 327 isolates, which consisted of B. subtilis (12 strains), B. amyloliquefaciens (5 strains), and B. licheniformis (3 strains). The inhibitory zone for the antagonistic effect was 9.0~12.0 mm in diameter. Although a small amount of traditional Doenjang was tested in this study, these results indicated that the potential risk of B. cereus in traditional Doenjang is lower than generally presumed. It is necessary to monitor the antagonistic effect of traditional Doenjang isolates against B. cereus.