• Journal of Microbiology and Biotechnology
• /
• 제21권6호
• /
• pp.545-555
• /
• 2011

The diversity elucidation by amplified ribosomal DNA restriction analysis and 16S rDNA sequencing of 96 associative diazotrophs, isolated from the feeder roots of tea on enriched nitrogen-free semisolid media, revealed the predominance of Gram-positive over Gram-negative bacteria within the Kangra valley in Himachal Pradesh, India. The Gram-positive bacteria observed belong to two taxonomic groupings; Firmicutes, including the genera Bacillus and Paenibacillus; and Actinobacteria, represented by the genus Microbacterium. The Gram-negative bacteria included ${\alpha}$-Proteobacteria genera Brevundimonas, Rhizobium, and Mesorhizobium; ${\gamma}$-Proteobacteria genera Pseudomonas and Stenotrophomonas; and ${\beta}$-Proteobacteria genera Azospira, Burkholderia, Delftia, Herbaspirillum and Ralstonia. The low level of similarity of two isolates, with the type strains Paenibacillus xinjiangensis and Mesorhizobium albiziae, suggests the possibility of raising species novum. The bacterial strains of different phylogenetic groups exhibited distinct carbon-source utilization patterns and fatty acid methyl ester profiles. The strains differed in their nitrogenase activities with relatively high activity seen in the Gramnegative strains exhibiting the highest similarity to Azospira oryzae, Delftia lacustris and Herbaspirillum huttiense.

• Journal of Microbiology and Biotechnology
• /
• 제21권4호
• /
• pp.374-378
• /
• 2011

To find alternative genetic resources for D-serine dehydratase (E.C. 4.3.1.18, dsdA) mediating the deamination of D-serine into pyruvate, metagenomic libraries were screened. The chromosomal dsdA gene of a wild-type Escherichia coli W3110 strain was disrupted by inserting the tetracycline resistance gene (tet), using double-crossover, for use as a screening host. The W3110 dsdA::tet strain was not able to grow in a medium containing D-serine as a sole carbon source, whereas wild-type W3110 and the complement W3110 dsdA::tet strain containing a dsdA-expression plasmid were able to grow. After introducing metagenome libraries into the screening host, a strain containing a 40-kb DNA fragment obtained from the metagenomic souce derived from a compost was selected based on its capability to grow on the agar plate containing D-serine as a sole carbon source. For identification of the genetic resource responsible for the D-serine degrading capability, transposon-${\mu}$ was randomly inserted into the 40-kb metagenome. Two strains that had lost their D-serine degrading ability were negatively selected, and the two 6-kb contigs responsible for the D-serine degrading capability were sequenced and deposited (GenBank code: HQ829474.1 and HQ829475.1). Therefore, new alternative genetic resources for D-serine dehydratase was found from the metagenomic resource, and the corresponding ORFs are discussed.

• 한국환경보건학회지
• /
• 제11권2호
• /
• pp.65-75
• /
• 1985

Microorganisms capable of utilizing diaminododecane containing amine groups diterminally were isolated from the soil by enrichment culture. One strain of these isolated strain, designated as EL-0112L, was selected for this study. The results of this study were as follows. 1. This isolated strain EL-0112L was identified as Microbacterium, from the results of morphological, cultural, and biochemical tests. This isolated strain was named temporarily Microbacterium sp. EL-0112L for convenience. 2. Microbacterium sp. EL-0112L was tested for ability to utilize different kinds of substitued alkanes containing cyan, amine, chloro, and thiol groups(monoterminally or diterminall substituted) as carbon source. Pentamethylenediamine, hexamethylenediamine, n-decane, laurylamine, and alkane derivatives containing cyan, chloro, and thiol groups were not utilized by Microbacterium sp. EL-0112L. 3. The alkane derivatives that did not serve as growth substrates were tested further in oxidation tests using resting cell preparation of Microbacterium sp. EL-0112 L. Alkane derivatives containing cyan, chloro, thiol groups, and n-decane were oxidized by Microbacterium sp. EL-0112 L. It is possible that this isolated strain is also able to degrade their substituted counterparts since they are structually similar to diaminododecane. The remarkable substrates that were being oxidized were dichlorodecane, and 1-dodecanethiol. Microbacterium sp. EL- 0112L could not oxidize pentamethylenediamine, and hexamethylenediamine. 4. The metabolic products formed from diaminododecane by Microbacterium sp. EL-0112 L were acid compound containing carboxyl group and not containing amine group. On the thin layer chromatography, Rf values of these metabolic products were different from that of the product formed by Corynebacterium sp. EL-0112L. These results suggested the specificity of diaminododecane as carbon source.

• Journal of Microbiology and Biotechnology
• /
• 제12권1호
• /
• pp.77-83
• /
• 2002

A bacterial consortium capable of utilizing a variety of polycyclic aromatic hydrocarbons has been isolated from a former manufactured gas plant site. The consortium consisted of four members including Arthrobacter sp., Burkholderia sp., Ochrobacterium sp., and Alcaligenes sp., which were identified and characterized by the patterns of fatty acid methyl esters (FAME analysis) and carbon source utilization (BIOLOG system). With the individual members, the biodegradation characteristics of aromatic hydrocarbons depending on different growth substrates were determined. FAME analyses demonstrated that microbial fatty acid profiles changed to significant extents in response to different carbon sources, and hence, such shift profiles may be informative to characterize the biodegradation potential of a bacterium or microbial community.

• Journal of Microbiology
• /
• 제35권1호
• /
• pp.10-14
• /
• 1997

The database of metabolic fingerprints generated using the GIolog system of lactic acid bacteria isolated from kimchi, described by Lee et al. (8), was used for the identification of 75 Leuconostoc isolates. The test strains were isoalted using a selective isolation medium specific for the genus Leuconostoc and examined for their ability to oxidize carbon sources using the Biolog system. The results show that the 75 test strains were identified to the known Leuconostoce clusters. It is suggested that the Biolog system can be applied for rapid identification of lactic acid bacteria isolated from kimchi.

• 아시안잔디학회지
• /
• 제5권2호
• /
• pp.81-86
• /
• 1991

The sludge, a waste of brewery industries, was examined for potentials as a natural organic fertilizer (or soil conditioner) for lawn. Trial products were measured for changes of physical, chemical properties in laboratory and seed germination and seedling growth in green house were also tested. The results are as the following:1The sludge from distilled liquor brewery contained high quantity of organic matter which had proper physical and chemical properties for lawn fertilizer (natural organic fertilizer, soil conditioner, top-dressing mix) . It showed good characteristics in handling and capabilities to be developed as commercial products for golf courses. 2.Sludge from beer company needs proper treatment to improve physical properties for futher degradiation. It is because aggregation of the sludge particles prevented microbial activities and changing to soluble form. 3.Green carbon can be used as carbon source for organic fertilizer production using brewery sludge, but it should not contain wood extract which inhibit seed germination and seedling growth.

• 청정기술
• /
• 제18권3호
• /
• pp.229-249
• /
• 2012

산업 발달로 화석 연료 사용이 급증하고 이에 따른 지구 온난화 문제와 자원 고갈 문제가 대두되어 지속 성장을 위협하고 있다. 따라서 지속 성장을 위해서 두 문제를 모두 해결하여야 한다. 현재 이산화탄소의 처리 방법으로 인식되고 있는 이산화탄소 포집 및 저장 기술(carbon capture and sequestration, CCS)의 환경 논란으로 인해 사후 처리 기술의 필요성이 커지고 있다. 이에 해결책중 하나로 부각되고 있는 이산화탄소 포집 및 재활용 기술(carbon capture and utilization, CCU)에 대해서 알아보았다. 이산화탄소 전환 기술은 이산화탄소 배출량 감소에 따른 지구 온난화 문제의 해결 뿐 아니라 탄소원의 재활용이란 측면에서 자원고갈 문제의 해결책으로 제시될 수 있겠다. 이산화탄소 전환 기술은 기상 전환과 액상 전환으로 나눌 수 있으며 기상 전환의 경우 필요 에너지 공급원과 온화한 반응조건에서 전환이 이뤄져야 하고 저에너지 소비 생성물 분리 정제 기술의 개발이 필요하다. 액상 전환의 경우, 반응 속도를 높일 수 있는 촉매 및 광감응제 개발과 함께 촉매, 빛, 전기의 혼성 시스템의 개발이 요구되어진다. 이산화탄소 전환 기술은 신재생 에너지 및 바이오산업의 경쟁력 향상을 위한 연결 기술로 그 가치가 매우 크다.

• Journal of Microbiology and Biotechnology
• /
• 제2권4호
• /
• pp.273-277
• /
• 1992

Treatment of poultry feces with Tolura sp. CH-30 produced a material that was significantly deodorized and showed a promotive effect on plant growth. Tolura sp. CH-30 grew on the poultry feces, deodorizing the feces by assimilation of volatile fatty acids, which are the source of the offensive odor, as a carbon source. Significant degradation of uric acid also occurred. In the treatment of feces with Tolura sp. CH-30, it was possible to deodorize feces in a short time, but reduction in the amount of urate-N was not enough. Urate-N inhibited plant growth due to an excessive nitrogen content produced as a result of rapid decomposition. Therefore, we propose a recycle-treatment plan using poultry feces treated with Tolura sp. CH-30. After the recycle-treatment, the amount of urate-N contained in the recycle-treated poultry feces was small and the recycle-treated poultry feces showed a promotive effect on plant growth when it was added at a nitrogen content of 1.6 g/600 g soil/pot.

• 미생물학회지
• /
• 제47권3호
• /
• pp.249-254
• /
• 2011

본 연구에서는 탄소원 및 질소원의 이용 패턴과 mycophenolic acid의 생성 패턴을 확인하기 위하여 먼저 5 L 발효조에서 mycophenolic acid 발효의 경시적 변화를 조사하였다. 그 다음에는 여러 가지 탄소원들이 세포 생장과 mycophenolic acid 생산에 미치는 효과를 조사하였다. 과당이 mycophenolic acid 발효에 가장 좋은 탄소원이었지만, 값이 고가인 단점이 있어서, 과당을 지니고 있는 설탕이 주성분인 당밀을 탄소원으로 사용한 결과 mycophenolic acid의 산업적 생산에 가장 좋은 것으로 확인되었다. 당밀을 첨가한 실험구는 포도당을 탄소원으로 사용한 대조구에 비하여 발효 생산성이 2배 이상 증가하였다. 양호한 세포 생장과 높은 mycophenolic acid 생산을 얻기 위하여 다양한 무기질소원과 유기질소원에 대한 실험을 실시하였다. 무기질소원들 가운데 요소는 암모늄 형태의 질소원을 천천히 공급함으로써 생장과 mycophenolic acid 생산을 저해하는 배양액의 급격한 pH 하락을 일으키지 않았다. 요소를 첨가한 실험구는 질산암모늄을 첨가한 대조구보다 발효 생산성이 3.6배 증가하였다. 카제인, 펩톤, casamino acid 같은 우유 단백질 유래 유기질소원들은 대조구에 비하여 mycophenolic acid 발효 생산성을 최고 3.4배까지 증진시켰다. 카제인의 가수분해물인 펩톤과 casamino acid는 mycophenolic acid 발효 생산성뿐만 아니라 세포 생장도 촉진하였다.

• 대한환경공학회지
• /
• 제27권5호
• /
• pp.519-524
• /
• 2005

국내 하수의 낮은 C/N비를 나타내는 특성으로 인하여 질소와 인의 효과적인 제거를 위해서는 추가적인 보조 탄소원의 주입이 필요한 실정이다. 여러 가지 적용 가능한 외부 탄소원 중, 음식폐기물은 다량의 유기물을 함유하고 있어 다양한 전처리를 통하여 하 폐수 고도처리 공정의 외부탄소원으로 이용가치가 높다고 할 수 있다. 본 연구에서는 음식폐기물 고속발효건조 과정에서 발생하는 음식폐기물 응축수를 A/O 공정으로 구성된 막 결합 생물반응조의 외부탄소원으로 적용 가능성에 대해 평가하고 다양한 운전 조건에서의 질소 인 성분의 제거 효율을 살펴보았으며, 막 오염에 영향을 미칠 수 있는 다양한 인자들에 대한 평가를 실시하였다. 실험 결과 무산소 조건에서 0.19 g $NO_3-N/g$ VSS/day의 탈질율을 얻을 수 있었으며 연속운전에서는 음식폐기물 응축수 주입을 통하여 총질소와 인 성분의 제거율을 각각 최대 64%, 41% 향상 시킬 수 있었다. 또한 유입수 유량의 0.5% (vol/vol)의 외부탄소원 주입 조건에서도 효과적인 처리효율을 얻을 수 있었으며, 전체 공정의 수리학적 체류시간 8시간 이상, 무산소조와 호기조의 체류시간은 각각 3시간, 5시간에서 최적의 처리효율을 나타내었다. 실제 생환하수 처리 시, 질소와 인의 제거효율은 증진되었으나 막 결합 생물 반응조 내의 전체 입자의 크기 증가 및 미생물 체외고분자 물질 중 단백질 성분의 증가로 인하여 전체 막 저항 값이 증가하는 경향을 보였으며, 유입수의 고형물질의 조절을 통하여 막 오염을 줄일 수 있었다.