• Korean journal of applied entomology
• /
• v.30 no.4
• /
• pp.291-293
• /
• 1991

Inter-regional difference in median lethal concentration of Bacillus thuringiensis diamondback moth was disclosed to be high. Pyungchang strain showed at most 41 times resistance compared to KN-IA strain of which $LC_{50}$ value was 5.5 ppm. and Oksan strain Showed 11 times resistance. The JMC strain, susceptible to pyrethroids, also showed 12 times resistance against B.T., suggesting difference in resistance mechanism between pyrethroid and B.t.

• Asian Journal of Turfgrass Science
• /
• v.13 no.4
• /
• pp.213-222
• /
• 1999

The toxic effects of four pesticides on the entomopathogenic nematodes. Heterorhabditis bacteriophora NC strain, Steinernema glaseri NC and Dongrae strain were tested by checking the mortality of infective juveniles(Ijs) in aqueous solution of pesticide. Mortality of Ijs was influenced by pesticide and concentration and soaking time. The herbicide alachlor and insecticide fenitrothion were toxic to Ijc of three entomopathogenic nematodes. But, the fungicides mepronil and tolclofos-methyl were nontoxic to Ijs. Tolclofos-methyl showed significantly very week toxicity at 28 days after soaking for S. glaseri NC strain. H. bacteriophora NC strain was more highly sensitive to high temperature condition then were the other nematodes.

• Korean Journal of Microbiology
• /
• v.9 no.1
• /
• pp.27-31
• /
• 1971

This experiment was carried out to research for the use of the mycelium and enzyme on the production of fermented feed. Among 354 strains isolated from natural sources, 3 strains of useful yeasts were selected and identified, and the cultural conditions of these strains were examined. The results obtained were as follows. 1) The strian No.55, No.112 and No. 340 selected were identified Endomycopsis fibuliger, Endomycopsis javanensis and Candida tropicalis, respectively. 2) The optimum pH and sugar concentration of the medium for the strain No.55, No.112 and 340 selected was around pH 6.5and Bllg.10.deg.. The optimum temperature for the growth of the strain No.55 and No.112 selected was 30.deg.C and was 25.deg.C of strain No.340. 3) The strain No.55 and No.112 were grown exceedingly well on the media containing 0.1 percent of (NH/sub 4/)/sub 2/SO/sub 4/.

• Journal of Microbiology and Biotechnology
• /
• v.4 no.4
• /
• pp.270-273
• /
• 1994

Pseudomonas putida 3SK, which was constructed by the conjugal transfet of the $CAM::TOL^{*}$ plasmid of Pseudomonas putida CSnA and the NAH plasmid of Pseudomonas putida KCTC 2403 into n-alkane assimilating Pseudomonas putida KCTC 2405, showed a broad degradation spectrum and floc-forming ability. This strain degraded m-toluic acid, naphthalene, camphor and decane simultaneously. $Hg^{2+}$ at the concentration of 1 ppm in the minimal medium could not inhibit the growth of this strain. The degradation of m-toluic acid by Pseudomonas putida 3SK was not repressed by the easily utilizable compounds, such as glucose and succinate. But, the addition of formalin inhibited the growth of Pseudomonas putida 3SK. After the cultivation of this strain on the artificial wastewater containing m-toluic acid, naphthalene, camphor and decane for 24 hr, the initial COD value (1500) of the artificial wastewater was declined to 300.

• Korean Journal of Environmental Agriculture
• /
• v.31 no.2
• /
• pp.185-191
• /
• 2012

Background: The removal of phosphate(P) in the wastewater is essential for the prevention of eutrophication in the river and stream. This study was initiated to evaluate the P removal by three strains of bacteria isolated from industrial wastewater. The three strains of bacteria, A1, A2, and A3, isolated were identified as Stenotrophomonas maltophilia strain CUPS 3, Rhodococcus erythropolis strain Sco-C01, Bacillus sp. 3434BRRJ, respectively. METHODS AND RESULTS: The experiments evaluating the effects of temperature, P concentration, aeration, and carbon sources on P removal by Bacillus sp. 3434BRRJ were performed in the following conditions: temperature, 15, 25 and $30^{\circ}C$; P concentrations, 20, 30, and 40 mg/L; oxygen condition, aerobic, anaerobic/aerobic conditions; carbon sources, glucose, acetate and mixture of glucose and acetate. As a result, the best optimum conditions for P removal by Bacillus sp. 3434BRRJ were as follows: temperature, $30^{\circ}C$; P concentration, 20 mg/L; carbon sources, mixture of glucose and acetate; oxygen concentration, anaerobic and aerobic conditions. The P removal efficiencies by Bacillus sp. 3434BRRJ, Stenotrophomonas maltophilia strain CUPS, and Rhodococcus erythropolis strain Sco-C01 were 99%, 50%, 20%, respectively. CONCLUSION: As a result, the best optimum conditions for P removal by Bacillus sp. 3434BRRJ selected and used in this study were as follows: temperature, $30^{\circ}C$; P concentration, 20 mg/L; carbon sources, mixture of glucose and acetate; oxygen concentration, anaerobic and aerobic conditions.

• Korean Journal of Poultry Science
• /
• v.17 no.1
• /
• pp.7-15
• /
• 1990

The present study was undertaken to determine the effect of different body hair color (Native type) and commercial white laying hen (Improvement, Nick Chick strain) on cholesterol, triglyceride and protein concentration in serium. Experimental hens were selected out of yellow-brown body hair color strain (10 heads), green-black body hair color strain (13 heads), white body hair color strain (7 heads), black-bone strain (10 heads) as native type and commercial white laying hen (30 head,3) as improved variety. Experimental diet was fed identically for 4 weeks in total groups. The results of the experiment obtained were summerized as follows：1. Serium cholesterol contents were the highest in commercial white laying hen ($172.50\pm$13.45 mg/100 $m\ell$) (p＜0.01;, and higher in white color strains than body hair color strain groups. Body hair color strain groups were similar in serium cholesterol contents. 2, Serium triglyceride concentration also showed no response among native type groups, however commercial white laying hen group shelved significatly difference. (p＜0.01) 3. Serium protein contents were the highest in commercial white laying hen group ($6.24\pm$0.23 mg/100 $m\ell$). (p＜0,01) Increasing the serium cholesterol, triglyceride and protein contents in commercial white laying hen group than color strain group of native type was considered to improved grade.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.9
• /
• pp.1259-1265
• /
• 2010

The filamentous cyanobacterium Arthrospira platensis strain MMG-9 was isolated from a rice field. The ability of this strain to synthesize the bioactive compound indole-3-acetic acid (IAA) was demonstrated. IAA was extracted from the culture of A. platensis strain MMG-9 and its identity was confirmed by thin-layer chromatography (TLC) as well as by high-performance liquid chromatography (HPLC). The IAA precursor L-tryptophan was required for IAA biosynthesis. Released IAA increased with the increase of the initial concentration of L-tryptophan in the medium and with the incubation time. A. platensis strain MMG-9 accumulated more IAA than it released into the medium. The bioactivity of the secreted IAA was shown by its effect on the formation of roots by Pisum sativum. There was a significant positive effect of the supernatant of cultures of A. platensis strain MMG-9 on the number of lateral roots of P. sativum, whereas a negative effect on root length was observed.

• Fisheries and Aquatic Sciences
• /
• v.18 no.4
• /
• pp.349-357
• /
• 2015

To reutilize fisheries waste, we isolated a bacterial strain from a coastal area located in Busan. It was identified as Bacillus licheniformis TK3-Y. Using plate assay and 500-mL flask experiments, we found that the isolate simultaneously possessed cellulolytic, proteolytic, and lipolytic activities with salt tolerance. 10% (v/v) inoculums, were used to examine the biodegradation characteristics of the TK3-Y strain on carboxymethylcellulose, skim milk, and olive oil media. The optimum conditions for pH, temperature, agitation speed, and NaCl concentration on each 1% substrate were 6, $50^{\circ}C$, 180 rpm, and 17.5%, respectively. Under optimal conditions, the TK3-Y strain showed 1.07 U/mL cellulolytic, 1,426 U/mL proteolytic, and 6.45 U/mL lipolytic activities. Each enzyme was stable within a range of 17.5-35% NaCl. Therefore, the salt tolerance ability of strain TK3-Y was superior to other related strains. In degradation of a mixed medium containing all three substrates, both the cellulolytic and proteolytic activities were somewhat lower than those on each single substrate, while the lipolytic activity was somewhat higher. From the above results, the TK3-Y strain appears to be a good candidate for use in the efficient treatment of fisheries waste in which components are not collected separately.

• The Korean Journal of Food And Nutrition
• /
• v.9 no.1
• /
• pp.21-28
• /
• 1996

This study was attempted to investigate the production of L-tyrosine by Brevibacterium flavum ATCC 14067. To select the strain which produce more L-tyrosine, mutants were induced by N-methyl-N'-nitro-nitrosoguanidine (NTG) treatment and phenylalanine auxotrophic mutants were induced by NTG and penicillin treatments. PFP resistant mutant was isolated from a phenylalanine auxotroph by retreatment with NTG and screened for increase of L-tyrosine production. PFP-326 mutant resistant to PPP (100ug/ml) was derived from phenylalanine auxotroph by mutagenesis with NTG and PFP-106 mutant resistant to PFP (1201g/ml) was derived from PFP-326 by mutagenesis with NTG. The composition of media for L-tyrosine production in strain PFP-106 was studied. PFP-106 mutant strain produced 50mg 11 of L-tyrosine while the parent strain produced 0.56mg 11 of L-tyrosine. The optimum composition of medium for L-tyrosine by strain PFP-106 was 10cA sucrose as carbon source, 3% ammonium sulfate as nitrogen source. The optimum cultural condition for producing L-tyrosine by strain PFP-106 was L-phenylalanine at a concentration of 1000g/mg.

• Journal of Microbiology and Biotechnology
• /
• v.16 no.10
• /
• pp.1597-1604
• /
• 2006

To screen for an anti-yeast substance (AYS), many bacteria were isolated from soil and a strain AY2000 was selected. The strain AY2000 was identified as Rahnella aquatilis by morphology, biochemical properties, and 16S r-RNA nucleotide sequence analyses. The strain AY2000 showed anti-yeast activity against Candida albicans and Saccharomyces cerevisiae, whereas R. aquatilis ATCC33071 as a type strain did not show the activity against the yeasts under the same condition. The growth of yeast cell was significantly inhibited by AYS produced by the strain AY2000, as shown by optical density and MTT assay. The minimum inhibitory concentration (MIC) of the AYS against S. cerevisiae and C. albicans at $28^{\circ}C\;was\;20{\mu}g/ml\;and\;60{\mu}g/ml$, respectively. The MIC of AYS against hyphae of C. albicans at $37^{\circ}C\;was\;600{\mu}g/ml$. Scanning electron microscopic analysis revealed that yeast cells treated with AYS had an irregular form with a wrinkled and rough surface.