Two Stage 발효에 의한 고산도 식초 생산

이영철,이금용,김형찬,박기범,유익제,안평욱,최춘언,손세형 한국산업미생물학회 1992 한국미생물·생명공학회지 Vol.20 No.6

산업적으로 산도 17.0% 이상의 고산도 식초를 생산하기 위하여 반연속식인 1st stage와 유가식인 2nd stage로 구성된 two stage 초산 발효를 온도 30 ℃, 교반속도 600 rpm, 통기량 0.1 vvm에서 실시하였다. 1st stage에서 초기 에탄올 농도를 50.0 g/ℓ, 잔류 에탄올 농도를 5.0 g/ℓ로 정하여 반연속적으로 초산발효를 하고, 2nd stage 에서 발효시간의 경과에 따라 에탄올을 유가식으로 첨가하여 초산발효액내의 에탄올 농도를 5.0 g/ℓ에서 10.0 g/ℓ로 유지했을 때 산도가 17.6%인 고산도 식초를 생산할 수 있었으며, 또한 이 ??의 최대 초산 생산성은 3.3 g/ℓ·hr였다. The production of vinegar containing 16.0 ∼18.0% of acetic acid was examined in two stage fermentation consisting of semi-continuous and fed-batch type. The optimum conditions were obtained when the fermentation was carried out at agitation of 600 rpm, aeration of 0.1 vvm and temperature of 30℃. The initial and residual ethanol concentration in 1st stage were 50.0 g/ℓ and 5.0 g/ℓ, respectively, and the ethanol concentration in 2nd stage was maintained from 5.0 to 10.0 g/ℓ. The maximum productivity was 3.3 g/ℓ-hr and the acidity was 17.6% after the two days of acetic acid fermentation.

Selection of Nitrate-nonutilizing Mutants of Hypoxylon atropunctatum, A Fungal Pathogen on Oak Species

Chun, Se-Chul,Fenn, P. The Korean Society of Plant Pathology 2000 Plant Pathology Journal Vol.16 No.5

Latent infections of healthy-appearing oaks of Hypoxylon atropunctatum complicates field studies by interfering with inoculation experiments to follow pathogenesis, fungal development and reproduction of this canker rot fungus. Mutants with unique and easily scorable phenotypes would be useful for inoculation studies. There is a broad range in the capacity of wild-type isolates to utilize nitrate as a sole nitrogen sources. Several types of nitrate-nonutilization mutants (nit1, Nit3, NitM) were selected from nitrate-utilizing wild-type isolates. Also, a few mutants of Hypoxylon atropunctatum were selected that could only grow poorly on basal medium supplemented with various nitrogen sources and even on yeast extract agar. These unknown mutants need to be characterized further. Nit mutants of Hypoxylon atropunctatum were readily selected, grew well and were recovered after inoculation into oak stems. These results suggest that nit mutants could be useful for inoculation studies in trees that contain latent infections.

Effect of Bacterial Population from Rhizosphere of Various Foliage Plants on Removal of Indoor Volatile Organic Compounds

Se-Chul Chun(천세철),Mung Hwa Yoo(류명화),Young Sook Moon(문영숙),Mi Ho Shin(신미호),Ki-Cheol Son(손기철),Ill-Min Chung(정일민),Stanley J. Kays 한국원예학회 2010 원예과학기술지 Vol.28 No.3

실내식물 9종의 근권부 하이드볼 배지에서 배양된 세균집단이 공기중 벤젠과 같은 휘발성 유기화합물의 제거효과에 미치는 영향이 조사되었다. 여러 식물 근권부의 배양토에서 배양된 세균 집단은 벤젠을 제거할 수 있었는데, Spathiphyllum wallisii Regel, Pachira aquatica, Ficus elastica, Dieffenbachia sp. ‘arrianne’Hort., Chamaedorea elegans 식물들은 벤젠의 초기농도를 1.000으로 기준하였을 때, 세균 집단이 전혀 없는 배지의 대조구 초기 농도 대비 잔류율이 0.596이었으나 상기 언급한 식물들은 0.741-1.000으로서 벤젠의 농도를 현저히 감소시켰다(LSD, P=0.05). 이와 같은 경향은 식물의 종류에 따라 차이는 있었지만 톨루엔의 경우에도 비슷하게 나타났다. 이러한 결과를 바탕으로 P. aquatic 근권부의 배양토로부터 배양된 세균 집단을 P. aquatica, F. elastica, S. podophyllum에 접종하였을 때 접종하지 않은 식물들에 비하여 벤젠과 톨루엔을 현저히 제거하는 효과가 나타나, 근권부의 미생물 집단을 이용하여 공기 중 휘발성 유기화합물(VOC)을 제거할 수 있음을 보여 주었다. Total bacterial populations were cultured from the Hydroball cultivation media in the rhizospheres of 9 different plants including Hedera helix L. and Dracaena deremensis cv. Warneckii Compacta, etc. These cultured bacterial populations were studied to test if the bacterial populations in the plant growing pots may play a role on removal of volatile organic compounds (VOCs) such as benzene and toluene in the air. To meet this objective, first, we tested the possibility of removal of VOCs by the cultured total bacteria alone. The residual rates of benzene by the inoculation of total bacterial populations from the different plant growth media were significantly different, ranging from 0.741-1.000 of Spathiphyllum wallisii ‘Regal’, Pachira aquatica, Ficus elastica, Dieffenbachia sp. ‘Marrianne’ Hort., Chamaedorea elegans, compared to the control with residual rate of 0.596 (LSD, P=0.05). This trend was also similar with toluene, depending on different plants. Based on these results, we inoculated the bacterial population cultured from P. aquatica into the plant-growing pots of P. aquatica, F. elastica, and S. podophyllum inside the chamber followed by the VOCs injection. The inoculated bacteria had significant effect on the removal of benzene and toluene, compared to the removal efficacy by the plants without inoculation, indicating that microbes in the rhizosphere could play a significant role on the removal of VOCs along with plants.

A Seedborne Fungus Bipolaris spicifera Detected from Imported Grass Seeds

Chun, Se-Chul,Loo, Han-Mo,Lee, Sang-Hun,Jung, Il-Min The Korean Society of Plant Pathology 2003 Plant Pathology Journal Vol.19 No.3

Seedborne fungus Bipolaris spicifera, which has not been previously reported in Korea, was detected from import-ed grass seeds in the country. The most frequently detected fungi from the seeds were Fusarium species, Ulocladium atrum, B. spicifera, Alternaria, and Cuvularia lunata among 17 different seed samples of the family Gramineae. Detection frequencies of B. spicifera were 11,8,5% in Bermuda grass, tall fescue, and mixed lawn grass imported from USA, respectively, and 9% in mixed lawn grass imported from Italy. This suggests that important seedborne pathogen could be spread between countries through seed sources. The pathogen was seed-transmitted causing damping-off of Bermuda grass seedlings and showed strong pathogenicity to vice, corn, Bermuda grass, sorghum, and tall fescue. However, it did not infect wheat and blue grass.

Selection of Nitrate-nonutilizing Mutants of Hypoxylon atropunctatum, a Fungal Pathogen on Oak Species

Se-Chul Chun,P. Fenn 한국식물병리학회 2000 Plant Pathology Journal Vol.16 No.5

Determination of Carbon Source Utilization of Bacillus andPythium Species by Biolog?? Microplate Assay

Se-Chul Chun,R.W. Schneider,Ill-Min Chung 한국미생물학회 2003 The journal of microbiology Vol.41 No.3

The carbon utilizations of Bacillus species and Pythium species were investigated by using a Biolog microplate assay to determine if there are differences in the carbon utilizations of selected strains of these species. It may be possible to afford a competitive advantage to bacterial biological control agents by providing them with a substrate that they can readily use as a carbon source, for example, in a seed coating formulation. Microplates, identified as SFP, SFN and YT were used to identify spore-forming bacteria, nonspore-forming bacteria, and yeast, respectively. Bacterial and mycelial suspensions were adjusted to turbidities of 0.10 to 0.11 at 600 nm. One hundred microliters of each of the bacterial and mycelial suspension were inoculated into each well of each of the three types of microplates. L-arabinose, D-galactose, D-melezitose and D-melibiose of the 147 carbohydrates tested were found to be utilized only by bacteria, and not by Pythium species, by Biolog microplate assay, and this was confirmed by traditional shake flask culture. Thus, it indicated that the Biolog microplate assay could be readily used to search for specific carbon sources that could be utilized to increase the abilities of bacterial biological control agents to adapt to contrived environments.

Characterization of Chitinase in Oak Tissues and Changes in Its Activity Related to Water Stress and Inoculation with Hypoxylon atropunctatum

Chun, Se-Chul,Fenn, Patrick,Kim, Kyung-Soo The Korean Society of Plant Pathology 1999 Plant Pathology Journal Vol.15 No.3

Chitinase activities from Shumard oak tissues were determined to study changes in chitinase activities related to water stress. The enzyme extracted in sodium acetate buffer (0.1M, pH 4.5) was assayed by a colorimetric method. In addition, the fungal hyphae of Hypoxylon atropunctatum in xylem tissues of oak were observed through scanning electron microscopy. The enzyme in oak tissues was mainly endochitinase, and optimum pH for enzyme activity was 5. Specific chitinase activities from both of stems held under high relative humidity (ranges of 0.63-1.11 pKatal/$\mu\textrm{g}$ of protein) and stems held under low relative humidity (ranges of 0.41-0.99 pKatal/$\mu\textrm{g}$ of protein) were significantly increased following fungal inoculation with H. atropunctatum. However, there was no significant difference in chitinase activities between tissues held under high and low humidities, which might be due to fungal chitinase. Scanning electron microscopy showed holes in fungal hyphae in the xylem tissues of stems held under high humidity but not in the stems held under ow humidity, suggesting that hyphae might be hydrolyzed by plant hydolases such as chitinase.

Effect of the Extract Methods of Gourd Seeds on Detection of Cucumber Green Mottle Mosaic Virus by Enzyme-linked Immunosorbent Assay

Chun, Se-Chul,Lee, Keumhee,Song, Y. S.,Ko, K. I.,Kim, B. K. 建國大學校附設農業資源開發硏究所 2002 農資源開發論集 Vol.24 No.-

박과 종자로부터 효율적인 오이녹반모자이크 바이러스(CGMMV) 추출방법을 ELISA에 의하여 조사 비교하였다. 종자를 30분에서 48시간 바이러스 추출 완충 용액에 침지하여 추출한 방법, 2시간 침지 후 2시간 냉동시키고 해동하여 10시간 동안 방치하여 추출한 방법을, 종자를 분쇄하여 추출하는 방법과 비교 평가하였다. 14시간 침지에 의한 추출과, 2시간 침지 후 2시간 냉동, 10 해동 방치 추출한 것은 분쇄법에 의한 추출법과 ELISA의 CGMMV 검출 효율이 유사하였다. 따라서, 노동이 많이 소요되는 분쇄법 대신에 14시간 침지 누출이나, 2시간 침지 후 2시간 냉동, 10시간 해동 방치하는 추출법을 사용할 수 있을 것임을 제시하여 주었다. 또한, 마이크로플레이트의 한 well 당 종자의 양을 1개보다는 10, 20개 사용하는 것이 검출효율이 유사하였다. 이는 총 사용되는 종자의 양이 일정하다고 할지라도, well 당 사용되는 종자가 20개일 경우까지는 well 당 사용되는 종자를 수를 증가시키더라도 바이러스를 검출할 효율은 동일함을 제시하여 주었다. Efficient methods of virus extraction from gourd seeds for the detection of enzyme-linked immnosorbent assay (ELISA) were compared. Seeds were soaked in sample extraction buffer (Agdia, Inc., Elkhart, IN USA) for 30min∼48hrs to exude cucumber green mottle mosaic virus. In addition, 2 hr soaking in sample extraction buffer and 2 hr of freezing followed by 10 hr thawing extract (2S-2F-10T) was used for the detection of the virus by ELISA. Whole seed and seed coat only were extracted for the detection of cucumber green mottle mosaic virus (CGMMV) by ELISA. Also, the effect of amount of seeds on the rate of detection of the virus by ELISA was studied. Soaking seeds for 14hr and 2S-2F-10T methods were similar to seed and only seed coat crushing methods on the efficiency of virus detection, indicating that seed soaking methods for the extraction could be used instead of mechanical breaking seeds with similar detection rate of the virus from gourd seeds. The results suggested that the chance of detection for the virus by increasing amount of seeds up to 20 seeds per well culd be same to one seed per well, although total amount of seeds for detection of the virus would be same for one seed and 20 seeds per well.

Data mining technique for medical informatics: detecting gastric cancer using case-based reasoning and single nucleotide polymorphisms

Chun, Se-Chul,Kim, Jin,Hahm, Ki-Baik,Park, Yoon-Joo,Chun, Se-Hak Blackwell Publishing Ltd 2008 Expert systems Vol.25 No.2

<P>Abstract</P><P>Although data mining and knowledge discovery techniques have recently been used to diagnose human disease, little research has been conducted on disease diagnostic modelling using human gene information. Furthermore, to our knowledge, no study has reported on diagnosis models using single nucleotide polymorphism (SNP) information. A disease diagnosis model using data mining techniques and SNP information should prove promising from a practical perspective as more information on human genes becomes available. Data mining and knowledge discovery techniques can be put to practical use detecting human disease, since a haplotype analysis using high-density SNP markers has gained great attention for evaluating human genes related to various human diseases. This paper explores how data mining and knowledge discovery can be applied to medical informatics using human gene information. As an example, we applied case-based reasoning to a cancer detection problem using human gene information and SNP analysis because case-based reasoning has been applied in medicine relatively less often than other data mining techniques. We propose a modified case-based reasoning method that is appropriate for associated categorical variables to use in detecting gastric cancer.</P>

Characterization of Chitinase in Oak Tissues and Changes in Its Activity Related to Water Stress and Inoculation with Hypoxylon atropunctatum

Se-Chul Chun,Patrick Fenn,Kyung Soo Kim 한국식물병리학회 1999 Plant Pathology Journal Vol.15 No.3