• 대한수의학회지
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• 제22권2호
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• pp.139-147
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• 1982

A total of 133 isolates of yeast-like fungi was tested for sensitivity to seven different antifungal agents. The yeast-like fungi tested were isolated from the milk from normal or mastitic bovine quaters or from bovine feces. They were 5 Candida albicans (C. albicans) isolates, 63 C. krusei, 27 C. tropicalis, 5 C. parapsilosis, 10 Torulopsis glabrata, 6 Rhodotorula sp., 6 Hansenula sp. and 1 Pichia sp. isolate. The antifungal agents tested were nystatin, griseofulvin, cycloheximide, 5-fluorocytosine, miconazol, clotrimazole and tolnaftate. In general, clotrimazole, miconazol and 5-fluorocytosine were more effective in antifungal activity in vitro against the test organisms than the rest of the agents tested. However, some of the isolates showed higher resistance to certain antifungal agents compared to the other isolates of the some species. They were: 1 C. albicans isolate to 5-fluorocytosine; 1 C. albicans to 5-fluorocytosine, miconazol and clotrimazole; 1 C. krusei to 5-fluorocytosine and cycloheximide; and 11 C. tropicalis isolates to cycloheximide. The minimum inhibitory concentrations(MIC) of clotrimazole were $12.5{\mu}g/ml$ or lower for all isolates tested except one C. albicans isolate, for which MIC of the drug was $100{\mu}g/ml$. On the other hand, the MIC's of cycloheximide were $6.5{\mu}g/ml$ or lower for all isolates except the following; all isolates of C. albicans ($100{\mu}g/ml$), C. pseudotropicalis ($200{\mu}g/ml$) and Rhodotorula sp. ($25-50{\mu}g/ml$), 11 C. tropicalis isolates ($100{\mu}g/ml$) and 1 C. krusei isolate ($200{\mu}g/ml$).

• 한국미생물·생명공학회지
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• 제25권3호
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• pp.311-316
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• 1997

A high xylitol producing yeast was isolated from the sludge of xylose manufacturing factory and then identified as Candida tropicalis DS-72 according to physiological properties. The strain was able to produce xylitol in a high concentration up to 72g/l from 100g/l xylose in 32 hours. Medium optimization for xylitol production by C. tropicalis DS-72 was performed. Effect of various nitrogen sources on xylitol production was investigated. Of nitrogenous compounds, yeast extract was the most suitable organic nitrogen nutrient for the enhancement of xylitol production. However, inorganic nitrogen resulted in a low cell concentration and did not produce xylitol. Effect of inorganic salts such as KH$_{2}$PO$_{4}$, and MgSO$_{4}$, 7H$_{2}$O on xylitol production was also studied. Optimal medium was selected as xylose 100g/l, yeast extract 10g/l, KH$_{2}$PO$_{4}$, 5 g/l and MgSO$_{4}$, 7H$_{2}$O 0.2 g/l. Xylitol of 88 g/l was produced from 100 g/l xylose in 30 hours using the optimal medium in a flask. In a fermentor, a fed-batch culture with 300g/l xylose was carried out. A final xylitol concentration of 240 g/l in the culture could be obtained in 43 hours of culture time by maintaining the high level of dissolved oxygen during growth phase and limiting the dissolved oxygen in the same culture during production phase. This result corresponded to a xylitol yield of 80% and a xylitol productivity of 5.58 g/1-h.

• 상하수도학회지
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• 제26권1호
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• pp.29-35
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• 2012

A bio-encapsuled media was developed to apply on reducing odors produced from organic waste treatment process. The microorganism, candida tropicalis, was encapsulated in sponge media consisted of polyurethane material. Sodium alginate as a natural polymer which does not affect to hydrophilic microbes and PEGDA(poly ethylene glycol diacrylate) as a artificial polymer were used for the encapsuled media. The media was evaluated with TMEDA (N,N,N',N'-tetramethylethylenediamine, 0.02~0.1%) as a catalyst at different temperature 25 and $35^{\circ}C$. The best performance was achieved with 0.02% of TMEDA at $25^{\circ}C$. The microbes' activity in the media was examined by Live/Dead cell method.

• 한국미생물·생명공학회지
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• 제19권2호
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• pp.135-139
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• 1991

Tridecanedioic acid (DC-13), starting material of the valuable musk ethylene brassylate, was obtained from n-tridecane by the Candida tropicalis mutant. The mutants were first obtained from primary screening step using the selective medium and then solid phase extraction sampling method was used for the selective isolation of organic acids from the cultured media of mutants. The resulting acids were directly converted to volatile tert-butyldimethyl silyl delivatives, which were then analyzed by gas chromatography. The efficient GC profiling method was used for the rapid identification of the mutant producing DC-13 in large quantity, and for the optimization of the culture conditions of mutant. The optimal culture conditions were found as follows: pH 8.0, 30$^{\circ}C$, 250rpm, 48hour of culture and $(NH_4)_2HPO_4$ as nitrogen source.

• Genomics & Informatics
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• 제3권1호
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• pp.24-29
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• 2005

TRPV2 is a non-specific cation channel expressed in sensory neurons, and activated by noxious heat. Particularly, TRPV2 has six transmembrane domains and three ankyrin repeats. TRPV2 has been cloned from various species such as human, rat, and mouse. Oocytes of Xenopus laevis - an African clawed frog ­have been widely used for decades in characterization of various receptors and ion channels. The functional property of rat TRPV2 was also identified by this oocyte expression system. However, no TRPV2 orthologue of Xenopus laevis has been reported so far. Hence, we have focused to clone a TRPV2 orthologue of Xenopus laevis with the aid of bioinformatic tools. Because the genome sequence of Xenopus laevis is not available until now, a genome sequence of Xenopus tropicalis - a close relative species of Xenopus laevis - was used. After a number of bioinformatic searches in silico, a predicted full-length sequence of TRPV2 orthologue of Xenopus tropicalis was found. Based on this predicted sequence, various approaches such as RT-PCR and 5' -RACE technique were applied to clone a full length of Xenopus laevis TRV2. Consequently, a full-length Xenopus laevis TRPV2 was cloned from heart cDNA.

• ALGAE
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• 제37권3호
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• pp.185-204
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• 2022

The genus Coolia A. Meunier 1919 has a global distribution and is a common member of epiphytic dinoflagellate assemblages in neritic ecosystems. Coolia monotis is the type species of the genus and was the only known species for 76 years. Over the past few decades, molecular characterization has unveiled two species complexes that group morphologically very similar species, so their limits are often unclear. To provide new knowledge on the biogeography and species composition of the genus Coolia, 16 strains were isolated from Bahía de La Paz, Gulf of California. The species were identified by applying morphological and molecular approaches. The morphometric characteristics of all isolated Coolia species were consistent with the original taxa descriptions. Phylogenetic analyses (large subunit [LSU] rDNA D1 / D2 and internal transcribed spacer [ITS] 1 / 5.8S / ITS2) revealed a species assemblage comprising Coolia malayensis, C. palmyrensis, C. tropicalis, and the C. cf. canariensis lineage. This is the first report of Coolia palmyrensis and C. cf. canariensis in Mexico and C. tropicalis in the Gulf of California. Our results strengthen the biogeographical understanding of these potentially harmful epiphytic dinoflagellate species.

• Journal of Microbiology and Biotechnology
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• 제25권6호
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• pp.856-862
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• 2015

The objective of this study was to optimize the slurry contents and salt concentrations for ethanol production from hydrolysates of the seaweed Eucheuma spinosum. A monosaccharide concentration of 44.2 g/l as 49.6% conversion of total carbohydrate of 89.1 g/l was obtained from 120 g dw/l seaweed slurry. Monosaccharides from E. spinosum slurry were obtained by thermal acid hydrolysis and enzymatic hydrolysis. Addition of activated carbon at 2.5% (w/v) and the adsorption time of 2 min were used in subsequent adsorption treatments to prevent the inhibitory effect of HMF. The adsorption surface area of the activated carbon powder was 1,400-1,600 m²/g and showed selectivity to 5-hydroxymethyl furfural (HMF) from monosaccharides. Candida tropicalis KCTC 7212 was cultured in yeast extract, peptone, glucose, and high-salt medium, and exposed to 80, 90, 100, and 110 practical salinity unit (psu) salt concentrations in the lysates. The 100 psu salt concentration showed maximum cell growth and ethanol production. The ethanol fermentations with activated carbon treatment and use of C. tropicalis acclimated to a high salt concentration of 100 psu produced 17.9 g/l of ethanol with a yield (Y_EtOH) of 0.40 from E. spinosum seaweed.

• 한국식품저장유통학회지
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• 제15권3호
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• pp.483-490
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• 2008

주석산은 포도에 상당량 함유되어 있어 포도 주스 또는 포도주의 저장 및 유통 기간 중에 침전물을 형성하여 품질을 저하시킨다. 본 연구에서는 주석산의 분해에 사용될 수 있는 효소 자원의 개발을 목적으로 주석산 분해 세균을 분리하고 그 특성을 조사하였다. 주석산의 함량이 높은 것으로 알려진 국산 캠벨얼리 포도주의 주박으로부터 주석산 분해세균을 집식배양한 후 주석산을 탄소원으로 함유하는 배지를 사용하여 주석산을 분해할 수 있는 세균을 분리하였다. 분리 균주 중에서 KMBL 5777과 KMBL 5778 두 균주가 주석산 함유 배지에서 생육도와 주석산 분해능이 가장 우수하였다. 이 두 균주의 형태학적, 생리학적 특성 및 165 rDNA를 분석하여 Acetobacter tropicalis로 동정하였다. 16S rDNA 염기서열의 상동성은 KMBL 5777 균주와 A. tropicalis LMG 1663 균주 사이에는 99.3%, KMBL 5778 균주와 A. tropicalis A77 균주 사이에는 99.8%로 나타났다. 두 균주에 의한 주석산 분해 조건을 조사한 결과 두 균주 모두 $25^{\circ}C$, 배지의 초기 pH 6.0에서 가장 우수한 생육도와 주석산 분해능을 나타내었다. 주석산 0.2%를 함유하는 배지에서 8일간의 배양 후에는 600 nm에서의 생육도가 약 2.3에 도달하였으며 주석산 분해율은 약 90%를 나타내었다. 온도에 의한 영향은 $25^{\circ}C$에 비하여 20, $30^{\circ}C$의 순으로 활성이 감소하였으며 37'E에서는 생육과 주석산 분해가 전혀 불가능하였다. pH 6에 비하여 pH 7, 5, 4, 3의 순으로 주석산의 분해속도가 감소하였으나 pH7, 5, 4의 경우에는 배양 8일 후 pH 6의 경우와 유사한 주석산 분해능을 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권2호
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• pp.230-240
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• 2016

Information on the effects of different yeast species on ruminal fermentation is limited. This experiment was conducted in a $3{\times}4$ factorial arrangement to explore and compare the effects of addition of three different live yeast species (Candida utilis 1314, Saccharomyces cerevisiae 1355, and Candida tropicalis 1254) at four doses (0, $0.25{\times}10^7$, $0.50{\times}10^7$, and $0.75{\times}10^7$ colony-forming unit [cfu]) on in vitro gas production kinetics, fiber degradation, methane production and ruminal fermentation characteristics of maize stover, and rice straw by mixed rumen microorganisms in dairy cows. The maximum gas production (Vf), dry matter disappearance (IVDMD), neutral detergent fiber disappearance (IVNDFD), and methane production in C. utilis group were less (p<0.01) than other two live yeast supplemented groups. The inclusion of S. cerevisiae reduced (p<0.01) the concentrations of ammonia nitrogen ($NH_3$-N), isobutyrate, and isovalerate compared to the other two yeast groups. C. tropicalis addition generally enhanced (p<0.05) IVDMD and IVNDFD. The $NH_3$-N concentration and $CH_4$ production were increased (p<0.05) by the addition of S. cerevisiae and C. tropicalis compared with the control. Supplementation of three yeast species decreased (p<0.05) or numerically decreased the ratio of acetate to propionate. The current results indicate that C. tropicalis is more preferred as yeast culture supplements, and its optimal dose should be $0.25{\times}10^7$ cfu/500 mg substrates in vitro.

• 한국식품과학회지
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• 제6권4호
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• pp.231-240
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• 1974

탄화수소자화성균주인 C. tropicalis var. KIST 76과 비(非)자화성균주인 T. cutaneum KIST 76-H의 혼합배양을 이용한 탄화수소효모(炭化水素酵母)의 생산기술을 개발하기 위하여 시험공강규모 회분(回分)배양연구를 수행하였는바 그 결과를 요약하면 다음과 같다. 1. C. tropicalis var. KIST 76과 T. cutaneum KIST 76-H는 안정한 혼합배양계(培養界)를 형성하며 균체수율, 단백질함량 및 균체생산속도는 각각 102%, 57.6% 및 3.2 g/l,hr로서 단독배양의 71%, 52% 및 2.4 g/l,hr에 비하여 현저히 향상된 우수한 산업균주(産業菌株)임을 알았다. 2. 혼합배양균주의 임계용존(臨界溶存)산소농도 및 친화성(親和性), km 값은 각각 1.5ppm, 0.228 ppm이였으며 최적조건에서 산소요구량은 9.2 mmole $O_2/g$ cell,hr였다. 한편 시험공장 발효조의 산소전달량은 $140{\sim}230$ m mole $O_2/l,hr$로서 필요한 산소량을 공급할 수 있었다. 3. 혼합균주의 생육적온(適溫)은 $33{\sim}36^{\circ}C$였으며 최적 pH 는 5.0이다. 그러나 pH 4.0에서 비증식속도, 균체생산성, 균체성분에 큰 영향을 주지 않고 무살균(無殺菌)조업이 가능하였다. 4. 최적 n-paraffin농도는 $1.5{\sim}2$ g/l이며 기질농도가 증가할수록 균체수율은 감소하였으나 비증식속도, 균체성분에는 큰 영향이 없었다.