J_Environmetal Microbiology and Engineering

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Antifungal Property of Microorganisms against Korea Oak Wilt Pathogen, Raffaelea quercus-mongolicae Yongsub YI* 1,2 and Jaejoung KIM 2 J-44 1 Department of Herbal Cosmetics Science, Hoseo University, Asan, Korea. 2 Department of Biochemistry, Hoseo University, Asan, Korea. *Corresponding author: yongsub@hoseo.edu This study was performed to investigate the antifungal materials to inhibit growth of Raffaelea quercus-mongolicae. Microbes were tested to screen antifungal activity. We found microbes showing antifungal activity. Two hundreds strains were isolated and incubated on the same fresh media. Five strains, SG 1-9, 1-12, SG 2-8, 2-10, and 2-17, were collected by determination of antifungal activity. Out of the five strains, organic compounds and proteins of SG2-17 strain broth was extracted for determination of antifungal activity. The organic compound showed antifungal activity, and the proteins extract didn’t show it. The 16S rDNA sequences of the above five strains were determined by the sequencing analysis. The 16S rDNA sequences were analyzed by the homology of BLAST program at NCBI. The homology search showed that SG 1-9 and 1-12 had 98% homology with Streptomyces cinnamoneus and 98% homology with Burkholderia cepacia, SG 2-8, 2-10, and 2-17 had 99% homology with Streptomyces fradiae, 97% homology with Staphylococcus epidermidis, and 99% homology with Staphylococcus epidermidis. Keywords: antifungal activity, Raffaelea quercus-mongolicae J-45 Optimization of the Conditions to make Solid Medium for Cyanobacteria Seung-Hee SHIN, Mi-Na YU, Eun-Hye PARK, Kyoung-Hee OH and Young-Cheol CHO* Dept. of Environmental Engineering, Chungbuk National University, Cheongju 361-763, Korea. *Corresponding author: choy@cbnu.ac.kr The conditions to make solid medium for cyanobacteria, especially focused on the kind and concentration of the solidifying agents, was optimized to cultivate these organisms on solid medium, which is accounted as the easiest way to establish the axenic culture. Two different culture media, modified CB and BG-11, supplemented with bactoagar, edible-agar, or agarose, were used. The bactoagar and edible-agar were washed with water to remove the potential inhibitors. The concentrations of the agents were 0.4% or 1.0%. In order to check the efficiency of the culture conditions, the number and diversity of cyanobacteria on the solid media were examined. The cyanobacterial numbers on the media with rinsed agars were not significantly different from those on the unprocessed ones, indicating the inhibitors in these solidifying agents cannot be removed with the simple washing. Although the numbers of colonies on the BG-11 media were generally higher than those on the modified CB media, lots of heterotrophic bacterial colonies were found. Based on the number and diversity of cyanobacteria on the media, we concluded that the modified CB medium with 0.4% of agarose is the adequate condition for solid culture of these organisms. [Supported by grants from Eco-Technopia 21 Project] Keywords: Cyanobacteria, Solid culture, Agarose 2011 International Symposium & Annual Meeting J-46 Qualitative Detection of Model Bacteria Expressing Iturin and Mop Cyclase and Microbial Community Analyses in Soils During the Cultivation of Plants Sung Eun KIM, Won-Sik CHOI, Jae Sun MOON and Sung Uk KIM* Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Korea. *Corresponding author: kimsu@kribb.re.kr To detect the microorganisms released into the environment at the molecular level, a recombinant strain P. fluorescens MX1 and B. subtilis, which have mop cyclase and iturin biosynthetic genes in the chromosome, respectively, were employed as model bacteria. Using specific fusion primers and the TaqMan probes, quantitative detections of model bacteria by real-time PCR were performed using genomic DNAs extracted from the soils of cucumber or tomato plants cultivated in pots and the greenhouse at intervals of three weeks for a six month period. The genomic DNAs from P. fluorescens MX1 and B. subtilis, except for probe DNAs, did not show any signals on the Southern blotting, indicating that the horizontal gene transfer from model bacteria to soil bacteria did not occur during the period monitored in pots and the greenhouse. In addition, the T-RFLP patterns of genomic DNAs obtained from the soils of both pots and the greenhouse suggest that the changes of microbial communities seem to be associated with the seasonal change in the soils. Thus, our data suggest that the bacteria used as model microorganisms do not give significant impacts on the other bacteria in pots and the greenhouse, although a long-term observation may be needed Keywords: Real-time PCR, , Horizontal gene transfer, Microbial community Effect of Fermentation Conditions on Biohydrogen Production from Lipid-rich Food Waste Soo Young MOON 1 , Hyo Sun KIM 1 , Can ZHANG 1 , Alma ABUG 1 , Sung Chan CHOI 2 and Young Sook OH* 1 1 Dept. of Environmental Engineering and Biotechnology, Myongji University, Yongin 449-728, Republic of Korea. 2 J-47 Dept. of Environmental Sciences and Biotechnology, Hallym University, Chunchon 200-702, Republic of Korea. *Corresponding author: ysoh@mju.ac.kr Although carbohydrate, protein, and lipid are basic components of organic material, hydrogen yield of carbohydrate fermentation has been reported to be significantly higher than that of protein and lipid. This study used lard as a model organic matter for lipid, and investigated its hydrogen production potential in batch anaerobic fermentation experiments under various combinations of stirring and CO2 scavenging condition to improve hydrogen production. To optimize hydrogen production, CO2 scavenging was found to be more effective in lard fermentation compared to stirring. In the presence of both CO2 scavenging and stirring, the hydrogen yield of lard increased from 4.5 to 185.8 ml-H2/g-VS, and the hydrogen content of the total biogas was in the range of 87 - 93% (V/V). Acetic, propionic, butyric, and valeric acids were produced during the fermentation and valeric acid was found to be the major fatty acid (33.1 - 67.1%) under all conditions. These results show that hydrogen production from lipid materials can be increased by minimizing the partial pressure of CO2 and hydrogen and activity of hydrogen-consuming bacteria. Keywords: hydrogen production, bioenergy, anaerobic fermentation The Korean Society for Microbiology and Biotechnology 407
Inhibition of Quorum Sensing-Controlled Virulence Factors and Biofilm Formation in Pseudomonas aeruginosa by 2,5-Dimethyl-4-Hydroxy-3(2H)-Furanone (DMHF) Can ZHANG 1 , Yu-Hong JIA 1 , Soo-Young MOON 1 , Sung-Chan CHOI 2 and Young-Sook OH* 1 1 Department of Environmental engineering and Biotechnology, Myongji University, Yongin 449-728, Korea. 2 J-48 Department of Environmental Sciences and Biotechnology, hallym University, Chunchon 200-702, Repubic of Korea. *Corresponding author: ysoh@mju.ac.kr 2,5-Dimethyl-4-hydroxy-3(2H)-furanone (DMHF), an innoxious food additive, has been proved to have antimicrobial activity recently. However, few studies focus on its inhibitory effect on quorum sensing (QS) system in pathogenic bacteria. In this study, the production of N-(3-oxododecanoyl)-L-homoserine lactone (OdDHL) was completely inhibited by 1.0 μM DMHF, while N-butyryl-L-homoserine lactone (BHL) production decreased on a dose dependent manner by DMHF. 1.0 μM DMHF also inhibited QS-controlled virulence factors such as rhamnolipid (55% decrease), lasA protease (40% decrease) and pyocyanin (52% decrease), and biofilm formation (83% decrease) of Pseudomonas aeruginosa PAO1 without growth inhibition. However, the production of vi rulence factors was restored by the addition of exogenous OdDHL as well as BHL, which suggests the inhibition of DMHF is due to the interruption of QS with las system as the main target. But the specific inhibition mechanism of DMHF on QS system in Pseudomonas aeruginosa remains unknown. This study also gives evidence that OdDHL plays more significant role in the production of QS-controlled virulence factors than BHL. Keywords: Quorum sensing (QS), Biofilm formation, 2, 5-Dimethyl-4-Hydroxy-3(2H)-Furanone (DMHF) The Effect of Treating Rice Straw with Lactobacillus plantarum BT-77 and Bacillus subtilis IN-55 on Silage Fermentation Hee Jong YANG 2,1 , Jae-Hwa HONG 1,3 , Seong-Yeop JEONG 1 , Chan-sun PARK 1 , Hong-gi KIM 3 , Byung-Dae YOON 1 , Yeon-Woo RYU 2 and Min-Soo KIM* 1 1 Bioindustrial Process Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Jeungeup 580-185, Korea. 2 Department of Molecular Science and Technology, Ajou University, san5, Wonchen-dong, Yeongtong-gu, Suwon, 443-749, Korea. 3 J-49 Department of Agricultural Biology, Chungnam University, Daejeon 305-764, Korea. *Corresponding author: godfilts@kribb.re.kr This study aimed to the effects of Lactobacillus plantarum BT-77 and Bacillus subtilis IN-55 on manufacturing of rice straw silage. We screened the strains having antibacterial and cellulase activity from traditional food and soil. Rice straw was treated with control (untreated; TGY broth media), BT-77 (4 × 105cfu/g; TGY broth media), IN-55 (4 × 105cfu/g; TGY broth media), BT-77 and IN-55 (4 × 105cfu/g; TGY broth media). Under optimal conditions (pH 5.5 and 30℃ for 7 days), treatments with BT-77 increased the concentrations of lactic acid and improved the aerobic stability of rice straw. Moreover, BT-77 showed inhibitory activity against most of the indicator strains. Additionally, we confirmed not only high levels of a cellulase enzyme activity from BT-77 and IN-55, but also cell-wall degradation through an electron microscope. In this study, other treatments could improve silage quality, but mixed treatment was more effective as an additive for rice straw silage. Keywords: Rice straw silige, Inoculant, cellulase 408 www.kormb.or.kr J-50 Characterization of Manganese Peroxidase Isozyme H4 of Phanerochaete chrysosporium Expressed from the yeast Pichia pastoris Yu-Lim SON, Saravana Kumar KUMAR, Ae-Young MO, Hyun-Young KIM and Seung-Moon PARK* Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Jeonju, 561-756. *Corresponding author: smpark@chonbuk.ac.kr Lignin biodegradation is a key step for carbon recycling in terrestrial ecosystems, where white-rot basidiomycetes fungi degrade this recalcitrant wood polymer enabling cellulose utilization by microbial populations. Three peroxidases involved in lignin degradation are known as lignin peroxidase (LiP), manganese peroxidase (MnP), versatile peroxidase (VP). The cDNA encoding manganese peroxydase isozyme H4 (MnPH4), isolated from Phanerochaete chrysosporium, was cloned into the pPICZα vectors and expressed in Pichia pastoris under the control of the methanol inducible alcohol oxidase I (AOXI) promoter. Enzyme assay indicated that the recombinant MnPH4 is efficiently secreted into the medium upon hemoglobin supplementation, at a maximum concentration of 500 U l -1 . The purified recombinant manganese peroxidase (rMnP) exhibited a 60 kDa molecular mass considerably larger, because of their glycosylation, and showed optimum pH of 4.5 and temperature at 35 o C. Keywords: Manganese Peroxidase, Phanerochaete chrysosporium, lignin peroxidase J-51 Optimization of the Method to Nucleic Acids from Cyanobacteria in the Environmental Samples Hye-Ryoung KIM, Eun-Hye PARK, Kyoung-Hee OH and Young-Cheol CHO* Dept. of Environmental Engineering, Chungbuk National University, Cheongju 361-763, Korea. *Corresponding author: choy@cbnu.ac.kr In order to develop the efficient method to extract nucleic acids from cyanobacteria in the environmental samples, the concentration and disruption methods for cyanobacteria were optimized. Three different kinds of filters, polycarbonate, cellulose nitrate, and GF/C, were used to concentrate cyanobacteria in the environmental samples. Cyanobacterial cells were treated with lysis buffer only or buffer combined with either of bead-beating or freezing-thawing. The extraction efficiency was examined through quantification of nucleic acids, and the purity was checked through PCR or RT-PCR. In case of DNA, the concentration with cellulose nitrate membrane and the disruption through bead-beating showed the highest extraction efficiency. On the other hand, the use of polycarbonate filter and freeze-thawing was adequate methods to extract RNA from cyanobacteria. It is needed to figure out why the extraction conditions for DNA and RNA were different. The methods developed in this study can be helpful to extract nucleic acids efficiently from the cyanobacteria in the natural aquatic environments. [Supported by grants from National Science Foundation of Korea] Keywords: Extraction, Cyanobacteria, Nucleic acid
Page 1 and 2: Isolation and Characterization of L
Page 3 and 4: Characterization of Phosphate-Solub
Page 5 and 6: Thermodynamic and Kinetic Analyses
Page 7 and 8: Identification of Novel Sugar Pathw
Page 9 and 10: J-32 Enhancement of Biohydrogen Pro
Page 11: Bioelectrochemical Fixation of CO2
Page 15 and 16: J-56 Development of Baeyer-Villiger

J_Environmetal Microbiology and Engineering

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