• Journal of Microbiology and Biotechnology
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• 제16권3호
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• pp.374-380
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• 2006

In this study, glucose, sucrose, and dextrin were found to be better carbon sources for the production of pullulan by Aureobasidium pullulans HP-2001. Maximal production of pullulan with 200 g/l sucrose as a carbon source was 54.2 g/l. The highest yield of pullulan from sucrose was 0.40, when the sugar concentration was 100 g/1. Optimal conditions for the continuous production of pullulan by A. pullulans HP-2001 in a 7-1 bioreactor were determined by studying the effects of composition of feed solution, dilution rate, and concentration of sucrose in the feed solution. Pullulan concentration and productivity with 100 g/l glucose and 2.5 g/l yeast extract were 38.1 g/l and 0.53 g/l h for 72 h, respectively, in a batch culture of A. pullulans HP-2001. When the substituted medium contained 100 g/l sucrose, 2.5 g/l yeast extract, and mineral salts, which is the same composition as the medium for the production of pullulan, the pullulan concentration and productivity were 74.9 g/l and 0.55 g/l h for 120 h, respectively. The production of pullulan at the steady state increased with a dilution rate up to 0.015/h, and its concentration was 78.4 g/l with a weight average molecular weight ($M_w$) of $4.0{\times}10^5$. Unlike a batch culture, however, the decline of the $M_w$ and the number average molecular weight ($M_n$) of pullulan was not found in the continuous culture of A. pullulans HP-2001. When the concentration of sucrose in the feed solution was 200 g/l, 113.5 g/l of pullulan was obtained at the steady state. The steady state was maintained longer in the continuous culture fed with the feed solution containing 200 g/l sucrose than when fed with the feed solutions containing either 100 or 150 g/l sucrose.

• Preventive Nutrition and Food Science
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• 제2권1호
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• pp.66-70
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• 1997

A mixed-culture of Gluconobacter suboxydans IFO 3172 and Saccharomyces uvarum IFO 0751 was per-formed in a synthetic medium. the optimal inculum ratio of G. suboydans and S. uvarum for mixed-culture fermentation was 150:1. The optimum pH, incubation temperature and aeration rate for mixed-culture fer- mentation were 5.0, 3$0^{\circ}C$ and 2.25vvm, reapectively. As a result of batch pure-and mixed-culture fer-mentation, specific growth rate in pure-culture of both strain was lower than that in mixed-culture. The yield of cell mass from S. uvarum exclusively decreased. The growth rate of the mixed-culture was very similar to the pure-culture in the begining of culture, but it has been decreased after 16hrs. In the mean time, S. uvarum in mixed-culture fermentation could grow due to fructose converted, but it could not row in pure-culture fermentation. Thus, the relationship was a sort of commensalism. The kinetic parameters cal-culated through steady-state results during continuous fermentations are as follows :{TEX}$$\mu$_{max1}${/TEX}=0.118({TEX}$h^{-1}${/TEX}), {TEX}$Ks_{1}${/TEX}=0.330(g/L),:{TEX}$$\mu$_{max2}${/TEX}=0.162({TEX}$h^{-1}${/TEX}), {TEX}$Ks_{2}${/TEX}=0.038(g/L). The yield of bacterial cell mass relatively constant, but yield of yest cell mass was gradually decreased.

• The Plant Pathology Journal
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• 제40권1호
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• pp.16-29
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• 2024

The Colletotrichum gloeosporioides species complex includes many phytopathogenic species, causing anthracnose disease on a wide range of host plants and appearing to be globally distributed. Seventy-one Colletotrichum isolates in the complex from different plants and geographic regions in Korea were preserved in the Korean Agricultural Culture Collection (KACC). Most of them had been identified based on hosts and morphological features, this could lead to inaccurate species names. Therefore, the KACC isolates were re-identified using DNA sequence analyses of six loci, comprising internal transcribed spacer, gapdh, chs-1, his3, act, and tub2 in this study. Based on the combined phylogenetic analysis, KACC strains were assigned to 12 known species and three new species candidates. The detected species are C. siamense (n = 20), C. fructicola (n = 19), C. gloeosporioides (n = 9), C. aenigma (n = 5), C. camelliae (n = 3), C. temperatum (n = 3), C. musae (n = 2), C. theobromicola (n = 2), C. viniferum (n = 2), C. alatae (n = 1), C. jiangxiense (n = 1), and C. yulongense (n = 1). Of these, C. jiangxiense, C. temperatum, C. theobromicola and C. yulongense are unrecorded species in Korea. Host plant comparisons showed that 27 fungus-host associations are newly reported in the country. However, plant-fungus interactions need to be investigated by pathogenicity tests.

• Journal of Microbiology and Biotechnology
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• 제18권3호
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• pp.560-567
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• 2008

An efficient method to produce water-soluble polysaccharides from Lentinus lepideus is described. The productivity of both endopolysaccharides (PPS) and exopolysaccharides (EPS) was compared under various culture conditions. The effect of treating their own PPS and EPS on immune cytokine production was also studied in relation to culture factors. High yield production of EPS required a moderate culture temperature $(25^{\circ}C)$ as well as long culture period (16-20 days). In contrast, PPS production required a high culture temperature $(30^{\circ}C)$ and short culture period (8 days). Most of the carbon sources did not affect polysaccharides and mycelial production except for sucrose. Immune cytokine levels in the EPS treatment varied among carbon sources or culture periods. PPS did not appear to affect much on the production of cytokines, regardless of the culturing factors, except for the culture period. These results suggest that the optimal culture conditions for L. lepideus vary according to culture purposes, and different culture conditions should be used for different targets including mycelial biomass, EPS, and PPS. Whereas the immunomodulating activitiy of EPS appeared to be affected by culture conditions in L. lepideus, that of PPS did not.

• 한국지역지리학회지
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• 제5권1호
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• pp.91-100
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• 1999

본 연구는 1998년 9월 11일부터 11월 10일까지 경주에서 개최되는 '98 경주 세계 문화 엑스포를 중심으로 한 관광상품을 개발하기 위한 목적으로 연구를 수행하였다. 그 결과 경주지역의 기존관광코스의 경우 경주시내의 사적지 관광에만 국한하였고, 경주시에서 설정한 5개 관광권의 경우에 기존의 관광루트에 전혀 포함되지 않는 관광권(동해안권 북부문화권)이 있어 새로운 관광코스의 개발이 절실하다 하겠다. 따라서 본 연구에서는 이에 대한 해결책으로 6개 관광권을 묶어 '테마가 있는 문화 엑스포 관람'이라는 주제로 관광상품을 계획하였다. 경주시내권 서악권 불국사권을 묶어 '신라 유적 답사', 보문단지권은 '새 천년의 미소와 함께', 남산권은 '남산 불교 박물관 견학', 동해안권과 북부문화권을 끓어 '자연과 문화의 조화'라는 테마가 있는 여행을 제안한다.

• 생명과학회지
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• 제13권5호
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• pp.732-739
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• 2003

본 연구는 난구세포가 제거된 돼지 미성숙 난자와 포유동물 정자의 공배양이 체외핵성숙에 미치는 영향을 조사하기 위하여 실시하였다. 난구세포가 부착된 미성숙난자를 직경 3-5 mm난포로부터 채취하여 난구세포를 제거한 후 정자가 첨가된 tissue culture medium 199에서 배양하였다. 배양 후 48시간에 난자의 핵성숙을 핵막붕괴, 제일차 감수분열 중기, 제일차 감수분열 후기-말기, 제이차감수분열 중기로 판정하였다. 배양 후 제이차감수분열 중기로 성숙한 난자의 비율이 무첨가구에 비하여 정자가 첨가된 배양액에서 성숙시킨 미성숙난자에서 유의적인(P<0.01) 증가가 있었다$(31.9\pm1.8%\; vs\; 14.9\pm1.0%)$. 난자의 성숙 단계에 따른 정자의 노출시간과 정자가 유래한 종에 따라서는 차이가 없었다. 그러나 정자의 첨가농도에 따라 유의적인 차이가 인정되었다. 본 연구는 포유동물의 정자는 미성숙난자의 체외성숙을 촉진하는 물질을 갖고 있으며, 촉진 효과는 농도에 의존하는 것으로 암시하고 있다.

• 생명과학회지
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• 제6권2호
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• pp.94-103
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• 1996

To understand effect of inoculum size, cell density, sucrose concentration and concentrations of MS basal on suspension culture and protoplast isolation of wild viola(Viola patrinii DC.) callus from petiole segments this experiment was conducted. In the lot of 30 mesh inoculum size, two observations were; One was that a considerable increase in the fresh and dry weight of callus was determined. Another was that the callus mass was relatively compact compared with others. A recommendable cell density was 0.4g for 20ml culture medium and the higher sucrose concentration, the higher fresh and dry weight were obtained. The dilution of MS basal salt was differently affected on fresh and dry weight; the highest fresh weight was found in 1x MS salt, while the higest dry weight was in 1/3x dilution.The addition of casein hydrolysate(3g/L) was more effective to increase of both fresh and dry weight. THe contents of protein was great in the inoculum lots with larger inoculum sizeand higher concentration of MS basal salts contenting 3g/L of casein hydrolysate and higher sucrose compared with others. The greatest protoplasts were isolated from the lot of 10 mesh size treated with 1%pectinase SE-150 and 2% cellulase YC. In general, for optimal protoplast isolation the followingconditions were recommended; 1) Use of smaller cell size cultured for 2-5 weeks, and 2) more than 5 hours incubation using the combined mixture of the enzymes with proper concentrations.

• 게임&엔터테인먼트 논문지
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• 제2권3호
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• pp.38-43
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• 2006

현대 사회는 삶의 질이 높아짐에 따라 여가문화를 향유하고자 하는 요구가 증대되고 있다. 이는 문화산업의 발전으로 이어져 다양한 문화산업을 창출하고 있으며, 최근에는 디지털 기술의 발전과 맞물리면서 디지털 문화콘텐츠의 발전이 비약적으로 확대되고 있다. 특히 게임 산업은 첨단 기술과 접목된 종합예술분야로 다양한 부문과의 융합이 가능해 새로운 여가문화를 창출하고 있다. 본 논문에서는 이러한 시대적 상황을 고려하여 누구나 쉽게 접근한 수 있는 게임문화의 특징을 기반으로 하는 게임문화의 거리 조성방안을 제시하였다. 게임문화의 거리란 게임이 갖고 있는 문화적 특성을 물리적 플랫폼인 거리에 접목함으로서 게임문화의 다양한 활용은 물론 게임산업의 활성화를 위한 장을 마련하고자 하는 것이다. 본 논문에서는 게임문화의 거리 조성에 관한 타당성과 구성요소 및 물리적 거리 조성방안에 초점을 맞춰 연구하였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.402-405
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• 2000

Batch culture system and continuous culture system were used to investigate the removal of disperse dye using several white rot fungi. White rot fungi used in the study were Coriolus hirsutus IFO 4917, Lenzites betulina IFO 6266, Coriolus versicolor IFO 30340 and Phanerochaete chrysosporium IFO 31249. The results of the batch culture experiment showed that white rot fungi used in this study had excellent dye removal abilities. Phanerochaete chrysosporium IFO 31249 was especially effective on the removal of disperse dyes. And continuous treatment of disperse red-60 was studied under bioreactor with vertical matrix using Phanerochaete chrysosporium IFO 31249. The removal efficiency of disperse red-60 were more than 95% in 0.20 ${\sim} 1.50 $hr^{-1}$ dilution rate and 90% in $1.83h^{-1}$ dilution rate.

• Elastomers and Composites
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• 제50권3호
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• pp.189-195
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• 2015

In this study, we prepared epoxidized poly ethylene-ter-1-decene-ter-divinylbenzene (Epo-PEHV) as a reactive compatibilizer to prevent phase separation phenomenon which occurs upon blending polypropylene (PP) and ethylene-vinyl alcohol copolymer (EVOH). Firstly, PEHV was prepared under high catalyst activity according to content of catalyst and cocatalyst. After then, we modified vinyl group of the terpolymer with epoxy group. We observed that the terpolymer was successfully epoxidized by 1H-NMR and FT-IR analysis. The Epo-PEHV was added by 2, 5, 10% in PP/EVOH blends. The morphologies and mechanical properties of PP/Epo-PEHV/EVOH blends were analyzed by SEM and UTM, respectively. Epo-PEHV enhanced the interfacial adhesion of PP and EVOH blends.