• Microbiology and Biotechnology Letters
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• v.13 no.4
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• pp.383-389
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• 1985

Optimum conditions of PEG treatment for the intergeneric fusion of yeast protoplasts were investigated. Fusants were selected by nutritional complementation on minimal medium. The intergeneric fusion frequency between pro-toplasts of S. cerevisiae and C. tropicalis was distributed 10$^{-4}$ to 10$^{-6}$, depending on the combination of parental strains. PEG 4000 or 6000 are equally effective. 30%(w/v) PEG 4000 was found to be optimum and below 20% its stabilizing effect was lost, resulting in protoplast lysis, and optimum pH was 8.0. The efficiency of PEG was enhanced by higher temperature of the PEG solution, and by the addition of Ca ions. The stimulating effect of Ca ions in the range of 1 mM to 100 mM proved similar.

• Journal of the Korean Chemical Society
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• v.63 no.6
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• pp.435-439
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• 2019

An efficient one pot multicomponent synthesis of pyrimidinone derivatives of Biginelli type is described. 4-amino-6-aryl-pyrimidine-5-carbonitrile molecules were synthesized efficiently via three-component Biginelli-type condensation of aldehyde, malononitrile, and semicarbazone as urea substituent in the presence of a catalytic amount of PEG-400 as green medium under microwave irradiation. The reactions proceeded efficiently in the presence of microwave radiation to afford the desired products in good to excellent yields. Products have been confirmed by IR, and NMR spectral analysis. All the molecules were tested for their antimicrobial activity against E. coli, S. aureus, P. aeruginosa and C. tropicalis. Some of the compounds have shown moderate to good inhibition efficiency against both gram-positive and gram-negative bacteria. The potent activity was observed against the fungal species with minimum inhibition concentration 12.5 ㎍/mL.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.374-377
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• 2001

On the basis of high-osmotic tolerance and xylitol productivity, it was isolated a novel strain from soil of rice field. An isolated strain was tentatively designated as Candida sp. HY200, deduced from the systematic approaches of bacterial identification by Biolog $Microlog^{TM}$ and, revealed an interesting ability of flocculation during the cultivation. With respect to the osmotic-tolerance and flocculation ability, experiment was carried out to investigate the production of xylitol in high xylose concentration. When xylose concentration was 260 g/L, it was obtained 205 g/L xylitol with 79% of yield and 2.14 g/L ${\cdot}$ h of productivity Consequently, We convinced that Candida sp. HY200 stands a very favorable comparison with C. tropicalis.

• Microbiology and Biotechnology Letters
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• v.9 no.2
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• pp.77-82
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• 1981

Candide tropicalis was selected for its ability to utilize spent waste generated by the alcohol distillery using tapioca starch as a raw material. Optimum pH and temperature on batch culture of the organism were 4.0 and 3$0^{\circ}C$. The growth of the organism was markedly increased when 0.2% of ammonium sulfate, 0.002% of potassium phosphate dibasic, add 0.04% of magnesium sulfate were supplemented to the filtrate. At these conditions, maximum specific growth rate and saturation constant were 1.0 hr$^{-1}$ and 4.4 g.1$^{-1}$ , respectively. At a dilution rate of 0.5hr$^{-1}$ , a productivity of 1.84 g.1$^{-1}$ . hr$^{-1}$ was obtained and about 70% of carbohydrate was assimilated. Protein content of dried cell was about 60%.

• Animal Systematics, Evolution and Diversity
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• v.10 no.2
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• pp.157-187
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• 1994

This study includes the taxonomy , and a key to species of aphids in the family Lachnidae from Korea. Specimens examined in this study were collected from 24 kinds of plants. Samplings were accomplished at 95 localities in Korea from March, 1987 to August, 1994. A list of Korean lachnids are as follows. *1. Chinara atlantica (Wilson, 1919), *.2. C. cembrae(Seitner, 1936), *3. C. formosana (Takahashi, 1924), *4. C. fresai Blanchard, 1939, *5. C. idahoensis Knowlton,1935, 6. c. juniperi (de Geer, 1773), 7.C.kochi Inouye,1939, *8. C. laridicola (Matsumura, 1917), *9. C. laricis (Hartig, 2839), *10. C.longipennis (Matasumura, 1917), 11. C. orientalis (Takahashi, 1925), *12. C. pinidensiflorae(Essig & Kuwana, 1918), *13. C. piniformosana(Takahashi, 1923), *14 C. shinjii Inouye, 1938, *15. c. tujafilina (Del Guercio, 1909), *16 . c. watanabei Inouye, 1970, *17. C. togyuensis Seo. 1994. *18. C. deodarae Seo. 1994, *19. Eulachnus agilis (Kaltenbach, 1843), *20. E. pumilae Inouye, 1939, *21. E. thunbergi (Wilson, 1919), *22. Schizolachnus orientalis (Takahashi, 1924) , 23. Lachnus, Chosoni Szelegiewicz, 1975, 24. L. japonicus (Matsumura, 1917) , *.25. L. tropicalis 9van der Goot, 1916), *.26. Maculolachnus sumbacula (Walker, 1848), *27. M. paiki Seo. 1994, *28 Nipppolachnus piri Matsumura, 1917, 29. Stomaphis asiphon Szelegiewica, 1975, *30. S. japonica Takahashi, 1960, *31. S. yanonis Takahashi , 1918 , *32. Tuberolachnus salignus *(Gmelin, 1790). Of them , 27 species preceded by an asterisk were observed in this study, and keys to these 27 Korean lachnids are provided . The relationship between Korean lachnids and their host plants, and geogrpahical distribution are discussed.

• Applied Microscopy
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• v.23 no.2
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• pp.97-106
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• 1993

This study was done to elucidate the electron microscopic characteristics of certain pathogenic fungi. Four Candida species, (C. albicans, C. tropicalis, C. parapsilosis and C. glabrate) and Cryptococcus neoformans were cultured for 3 days at $30^{\circ}C$ in the Sabouraud dextrose medium. After incubation, they were stored at $4^{\circ}C$ for 24hours. Fine structures were analyzed by morphometry, and Tukey's HSD test was used for statistics. On scanning electron microscopy C. albicans and C. neoformans were similar in size but different in shape, showing sphero-shape or ovalo-shape in C. neoformans. Surface of C. neoformans was coarse and spiny, but Candida species examined were uniformly smooth. In size, C. glabrata was the smallest among them. Budding scar as seen on the surface of Candida species by the number ranging from 1 to 7. Cryptococcus neoformans showed one or two budding scar. On transmission electron microscopy the cytoplasm of most yeast cells showed plentiful glycogen particles, mitochondria, peroxisomes and vacuoles. However, cell walls were different among four Candida species and Cryptococcus neoformans. The cell wall of Candida species consisted of fibrous layer, that was electron dense layer and transparent layer, in contrast to Cryptococcus neoformans consisted of electron dense layer with lamellar structure. This layer was two times thicker than that of Candida species. The outer layer of cell wall was of radiating pattern.

• Microbiology and Biotechnology Letters
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• v.48 no.2
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• pp.193-204
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• 2020

Sixteen acetic acid bacteria (AAB) were isolated from blueberries and citric fruits of the Salto Grande region (Concordia, Entre Rios, Argentina) using enrichment techniques and plate isolation. Enrichment broths containing ethanol and acetic acid enabled maximum AAB recovery, since these components promote their growth. Biochemical tests allowed classification of the bacteria at genus level. PCR-RFLP of the 16S rRNA and PCR-RFLP of the 16S-23S rRNA intergenic spacer allowed further classification at the species level; this required treatment of the amplified products of 16S and 16S-23S ITS ribosomal genes with the following restriction enzymes: AluI, RsaI, HaeIII, MspI, TaqI, CfoI, and Tru9I. C7, C8, A80, A160, and A180 isolates were identified as Gluconobacter frateurii; C1, C2, C3, C4, C5, C6, A70, and A210 isolates as Acetobacter pasteurianus; A50 and A140 isolates as Acetobacter tropicalis; and C9 isolate as Acetobacter syzygii. The bacteria identified by 16S rRNA PCR-RFLP were validated by 16S-23S PCR-RFLP; however, the C1 isolate showed different restriction patterns during identification and validation. Partial sequencing of the 16S gene resolved the discrepancy.

• Korean Journal of Food Science and Technology
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• v.6 no.1
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• pp.6-11
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• 1974

Four new compounds; 2,2'-methylene-bis [3, 4, 6-trichloro ${{\beta}-(o-nitroanilino)$ propionoxy} benzene]; m.p. $200{\sim}202^{\circ}C,\;C_{31}H_{22}O_8N_4Cl_6$ 2,2'-methylene-bis [3, 4, 6-trichloro ${{\beta}-(p-nitroanilino)$ propionoxy} benzene]; m.p. $168-170^{\circ}C,\;C_{31}H_{22}O_8N_4Cl_6$ : 2,2'-Methylene-bis [3, 4, 6-trichloro ${{\beta}-(o-chloro-p-nitroanilino)$ propionoxy} benzene]; m.p. $170.5-172.5^{\circ}C,\;C_{31}H_{20}O_8N_4Cl_8$ : 2,2'-Methylene-bis [3, 4, 6-trichloro ${{\beta}-(c-methyl-p-nitroanilino)$ propionoxy} benzene]; m.p. $163-164^{\circ}C,\;C_{33}H_{26}O_8N_4Cl_6$-were synthesized by Mannich reaction from 2,2'-Methylene-bis (3, 4, 6-trichloroacetoxy benzene) and their antimicrobial activities against the microorganisms Staphylococcus aureus, Escherichia coli, Bacillus subtilis Natto, Brevibacterium ammoniagenes, Candida tropicalis, Rhodotorula glutinis, Pseudomonas ovalis, Aspergillus candidus Link, Aspergillus awamori Nakazawa. Aspergillus niger var. Tieghem, Aspergillus usami Sakakuchi, Penicillium notatum-were tested. 2,2'-methylene-bis [3, 4, 6-trichloro ${{\beta}-(o-nitroanilino)$ propionoxy} benzene] showed a strong antimicrobial activity against Bacilus subtilis Natto and Brevibacterium ammoniagenes.

• Biomedical Science Letters
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• v.24 no.4
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• pp.430-434
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• 2018

Candida glabrata is the second most prevalent causative agent for candidiasis following C. albicans. The opportunistic yeast, C. glabrata, is able to cause the critical bloodstream infections in hospitalized patients. Conventional identification methods for yeasts are often time consuming and labor intensive. Therefore, recent studies on sequence-based identification have been conducted. Recently, sequencing the D1/D2 domain of the large subunit ribosomal RNA gene and the internal transcribed spacers (ITS) 1 and ITS2 regions of the ribosomal DNA has proven useful for DNA-based identification of most species of fungi. In the present study, therefore, fungal ITS and D1/D2 domain regions were targeted and analyzed by DNA sequencing for the accurate identification of C. glabrata clinical isolates. A total of 102 C. glabrata clinical isolates from various clinical samples including bloodstream, catheterized urine, bile and other body fluids were used in the study. The results of the DNA sequence analysis showed that the mean standard deviation of species identity percent score between ITS and D1/D2 domain regions was $97.8%{\pm}2.9$ and $99.7%{\pm}0.46$, respectively. These results revealed that the D1/D2 domain region might be a better target for identifying C. glabrata clinical isolates based on DNA sequences than the ITS1 and ITS2 regions. However, in order to evaluate the usefulness of D1/D2 domain region for species identification of all Candida species, other Candida species such as C. albicans, C. tropicalis, C. dubliniensis, and C. krusei should be verified in further studies additionally.

• Journal of fish pathology
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• v.22 no.3
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• pp.343-352
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• 2009

Natural-killer-cell-enhancing factor (NKEF) belongs to the newly defined peroxiredoxin (Prx) family. It was originally isolated from human erythroid cells. The black rockfish NKEF cDNA was identified through the expressed sequence tag (EST) analysis of PBLs libraries. The full-length NKEF cDNA was 1433 bp long and contained an open reading frame (ORF) of 594 bp that encoded 198 amino-acid residues. The 5' UTR had a length of 39 bp, and the 3’UTR 800 bp. The deduced amino-acid sequence of the black rockfish had a density 93.4, 92.9, 87.8, 85.8, 84.8, 83.8, 80.3, 79.7, 77.2, and 75.2% that of the pufferfish, olive flounder, channel catfish, zebrafish, chicken, common carp, Myotis lucifugus, cattle, human PrxI, rat PrxI, human NKEF-A, and Xenopus tropicalis, respectively. The NKEF gene was expressed in all the tissues of the black rockfish. The RT-PCR indicated that the NKEF transcripts were predominantly in the spleen and gill, less dominantly in the PBLs, head kidney, trunk kidney, and liver, and least in the intestine and muscles. This is the first report on the existence of the NKEF-A gene in black rockfish.