• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.56-62
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• 2008

This study was carried out to investigate the changes in microflora, enzyme activity and sensory quality of four kinds of cheonggukjang during fermentation. Three different kinds of cheonggukjang were prepared with germinated soybeans using rice straw, Bacillus natto, B. natto plus Aspergillus oryzae, and the last one was prepared with non-germinated soybeans using rice straw. The pH values of cheonggukjang prepared with germinated or non-germinated soybeans increased up to 36 hr of fermentation and then decreased. The number of bacteria and molds increased significantly up to 24 hr of fermentation and then leveled off during fermentation. Acidic and neutral protease activities of all cheonggukjang continuously increased significantly during fermentation. ${\alpha}$- and ${\beta}$-Amylase activities of cheonggukjang decreased slightly during fermentation except cheonggukjang prepared with germinated soybeans using the mixed culture. The number of microflora, protease and ${\alpha}$-amylase activities were highest in cheonggukjang prepared with germinated soybeans using B. natto plus A. oryzae. The results of the sensory evaluation revealed that for overall acceptability, the cheonggukjang prepared with germinated soybeans using B. natto plus A. oryzae was similar to the cheonggukjang prepared with non-germinated soybeans using rice straw.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.335-339
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• 2010

A diesel-degrading bacterium, Gordonia sp. SD8, was isolated from soil contaminated with petroleum, and its diesel degradation was characterized in a soil as well as a liquid culture system. SD8 could grow in the mineral salt medium supplemented with diesel as a sole carbon and energy source. The maximum specific growth rate ($0.67{\pm}0.05\;d^{-1}$) and diesel degradation rate ($1,727{\pm}145$ mg-TPH $L^{-1}\;d^{-1}$) of SD8 showed at 20,000 mg-TPH $L^{-1}$ and $30^{\circ}C$, and then this bacterium could degrade high strength of diesel of 40,000 mg-TPH $L^{-1}$. The residual diesel concentration in the inoculated soil with SD8 was 3,724 mg-TPH kg-dry $soil^{-1}$ after 17 days, whereas the diesel concentration in the non-inoculated soil was $8,150{\pm}755$ mg-TPH kg-dry $soil^{-1}$. These results indicate that Gordonia sp. SD8 can serve as a promising microbial resource for the bioremediaion of contaminated soil with petroleum hydrocarbons including diesel.

• Food Science and Preservation
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• v.15 no.5
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• pp.774-781
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• 2008

was performed and Staphylococcus sciuri, Bacillus cereus, Escherichia coli, Proteus mirabilis, and Enterococcus faecalis were identified. No Salmonella strain, a typical contaminant of eggs, was found. The radiation sensitivities of isolated bacteria and Salmonella typhimurium, in an inoculated model system, were expressed in $D_{10}$ values. The ranges of $D_{10}$ values shown by S. typhimurium, S. sciuri, B. cereus, E. coli, P. mirabilis, and E. faecalis were 0.365-0.399 kGy, 0.418-0.471 kGy, 1.075-1.119 kGy, 0.280-0.304 kGy, 1.132-1.330 kGy, and 0.993-1.290 kGy, respectively. The growth of all six test bacteria in eggs (inoculated at $10^6-10^7\;CFU/g$) during 3 days of post-irradiation storage at ambient conditions ($25^{\circ}C$) was recorded. S. typhimurium was eliminated by irradiation at 3 kGy, and E. coli and S. sciuri were eliminated by irradiation at 5 kGy. The viable cell counts of B. cereus, P. mirabilis, and E. faecalis in eggs showed 4-6 log reductions after irradiation with 5 kGy.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.2
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• pp.173-180
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• 1996

Effects of inoculation with phosphate-solubilizing microorganisms, Pseudomonas putida and Aspergillus niger, were studied in both acidic red-yellow and alkaline calcareous soils cropped with pimiento. In red-yellow soil after cultivation, the amounts of soil available phosphorus on non-fertilizer and fertilizer plots inoculated with Aspergillus niger, and on rice straw plot inoculated with Pseudomonas putida and Aspergillus niger were significantly higher than uninoculation treatments, but there were no differences in calcareous soil. With inoculation of either Pseudomonas putida or Aspergillus niger, increase in phosphorous uptake by pimiento cultivated in calcareous soil was detected on non-fertilizer, and fertilizer plots except rice straw plot. Although there were no significant differences in soil cellulase activities among treatments, the activity was the highest on rice straw plot in red-yellow soil. The phosphatase activities in red-yellow soil were increased by the inoculation with Aspergillus niger only, and the activity in calcareous soil was improved by the inoculation with either Pseudomonas putida or Aspergillus niger.

• Korean Journal of Poultry Science
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• v.30 no.1
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• pp.49-54
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• 2003

This study was carried out to investigate the effects of the inoculated diet with Paecilomyces japonica on weight gain, feed efficiency and cordycepin contents in the breast and thigh meats of broilers. One hundred and twenty broiler chicks were divided into four dietary groups ; 1) control (basal diet), 2) T1 (substituted with 5% inoculated diet), 3) T2 (substituted with 10% inoculated diet) 4) T3 (substituted with 20% inoculated diet) during 4 weeks. Cordycepin contents of inoculated diet with Pacilomyces japonica was significantly higher than before inoculation (P<0.05). Body weight gain and feed efficiency were highest in T1 group when fed starter diet (P<0.05) but these were lowest in T3 group fed when fed finished diet (P<0.05). Body weight gain and feed efficiency were the lowest in T2 group for overall period than other groups. Cordycepin contents of breast and thigh meats were significantly higher in Pacilomyces japonica groups than control at 5 weeks of age (P<0.05). However, it was similar among the T1, T2 and T3 groups. These results indicated that body weight gain and feed efficiency tended to increase in birds fed replaced 5% inoculation diet Cordycepin contents of breast and thigh meats would be increased significantly in birds fed inoculated diet (P<0.05).

• Korean Journal Plant Pathology
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• v.2 no.2
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• pp.114-120
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• 1986

Significant reduction in disease severity of bacterial wilt (Pseudomonas solanacearum) on the susceptible tobacco cultivar BY 4 was observed until mid-July in a naturally infested field when bacterial suspensions of avirulent isolate were applied to tobacco root zones at one day before and fourty days after transplanting into the field. However, rapid increase in disease severity after mid-July resulted in the same severity $(70\%)$ as on cultivar BY 4 without the application of the avirulent bacterial suspension at the end of the season. Yield increase in cultivar BY 4 was $35\%$ due to the treatment, resulting in $10\%$ price increase. The suppression me chanism did not appear to be dependent upon the inhibition of the virulent bacterial multiplication by the avirulent bacteria in tobacco rhizosphere soil because of no significant difference in the density of the patho genic bacteria between treated and untreated plant root zones. However. penetration of the virulent bacteria into the root systems and their multiplication in tobacco stem were inhibited remarkably by preinoculation with avirulent one, suggesting that those are related to the suppression of disease incidence.

• Journal of Wetlands Research
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• v.19 no.4
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• pp.443-450
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• 2017

The objective of this study was to isolate algae growth inhibiting microorganism to biologically control Microcystis aeruginosa, which is a harmful cyanobacterium. Various bacterial strains were isolated in this study, and four bacterial strains of M1~M4 exhibited remarkable growth inhibiting activity against M. aeruginosa. Based on the 16S rRNA analysis, the isolated M1~M4 strains were identified, and isolated four strains were rod-type and gram-negative. In particular, as well as respective single strain, co-culture of the isolated M1~M4 strains showed obvious algicidal activity against M. aeruginosa. When mixed four strains were inoculated, about 50% of the chlorophyll a was reduced after two days, about 70% after four days, and about 80% after seven days. From these results mentioned above, the four bacterial strains may contribute to the control of harmful M. aeruginosa.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.1
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• pp.89-98
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• 1992

Glasshouse experiments were conducted to evaluate nodulation, and $N_2$ fixation of 73 strains of Bradyrhizobia isolated from nodules of groundnuts and/or cowpeas grown at various location in Korea and 31 strains of cowpea Bradyrhizobia obtained from overseas sources. Of the strains tested 51.9%, 26.4%, and 21.7% were rated fully effective, partially effective, and ineffective, respectively. Eight very effective strains were selected. Nodulation, shoot dry mass, whole plant dry mass, and plant total N content were significantly correlated with each other. The highly significant correlation of total N content and plant dry mass ($r=0.98^{**}$) indicates that plant dry mass can be used as a measure of strain effectiveness in preliminary test.

• Applied Biological Chemistry
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• v.28 no.3
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• pp.149-155
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• 1985

590 strains of Rhizobia were isolated from root nodules of the legumes collected at 223 sites in Korea. According to their host specificities they were classified into R. japonicum(218 strains), R. phaseoli(101 strains), R. trifolii(97 strains), R. meliloti(4 strains), R. leguminosarium(1 strain), Rhizobium species(101 strains), and unidentified species(159 strains). 3 potent strains R-138, R-168, and R-214 of R. japonicum have been selected based on the infectivity to soybean cultivar and effeciency of nitrogen fixation. It was observed that the fast-growing strains of R. japonicum contained 1 to 4 plasmids of M.W. of 35-300 Md. However, plasmids were hardly detected for the slow-growing strains.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.402-409
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• 2005

This study was undertaken to compare and estimate the severity of pitch canker of individual trees of Pinus rigida and Pinus rigida ${\times}$ P. taeda in two seed orchards in Jeju island, in which the orchards have been damaged by the pitch canker for seven years. Wind-pollinated two-year-old seedlings of P. rigida and P. rigida ${\times}$ P. taeda, in which the seedlings of P. rigida ${\times}$ P. taeda were from seeds of phenotypically selected, uninfected(but untested) trees, were inoculated with the pathogenic fungus, Fusarium circinatum, isolated from P. rigida and P. thunbergii. The virulence of the isolates was also identified. Statistically significant difference was found in 'stem cankers'(SC; ${\chi}^2=7.76$, P=0.05) among 4 plantations of P. rigida ${\times}$ P. taeda of two seed orchards. P. rigida was higher in 'top kill' (TK) and 'branch tip symptoms' (BT) than those of P. rigida ${\times}$ P. taeda. In artificial inoculation tests, mortality of the seedlings from the resistant candidates was 14% higher than that of the seedlings from the susceptible candidates. This result may becaused by unknown pollen trees and/or candidate tree selection based only on phenotype. Two of five fungal isolates, C-6-L(9) and C-6-L(19), showed significantly higher mortality (68% and 60%, respectively) than others, suggesting that these isolates can be used as virulent isolates for a mass artificial inoculation. Resistance candidate seedlings that were selected from this study can be utilized as useful materials for fundamental studies of genetics and biochemistry to breed resistance varieties to pitch canker.