• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.20-24
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• 2000

A 7-week growth trial was conducted to investigate the effects of yeasts (Kluyveromyces fragilis and Candida utilis) with or without cell wall chemical treatment (protoplasted) in formulated diets on growth and body composition of larval ayu (Plecoglossus altivelis). Three replicate groups of ap average weighing 100 mg were fed diets containing each level ($5{\%}$) of K. fragilis, protoplasted K. fragilis, C. utilis, protoplasted C. utilis or brewer's yeast as an additive. Survival rate of fish fed the diet containing protoplasted K. fragilis, C. utilis or protoplasted C. utilis was higher than that of fish tea the control diet (P<0.05). Body weight .gain of fish fed the diet containing protoplasted K. fragilis was higher than that of fish fed the control diet (P<0.05). Crude protein and ash contents of Ssh were not significantly affected by the different dietary yeasts (P>0.05), On the other hand, crude lipid content of fish fed the diet containing K. fragilis, protoplasted K. fragilis or brewer's yeast was higher than that of fish fed the control diet (P<0.05). Amino acids composition of fish was not significantly affected by the different dietary yeasts (P>0.05), except aspartic acid. The results suggest that protoplasted K. fragilis as an additive in micro-formulated diet can improve weight gain and body quality of larval ayu.

• The Journal of the Korean Society for Microbiology
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• v.35 no.1
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• pp.41-48
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• 2000

Bacteroides fragilis and Escherichia coli, normal colonic inhabitants, are the most frequently isolated bacteria in infected tissues, particularly in intraabdominal abscesses. This study was designed to determine whether enteric bacteria may alter the B. fragilis-induced expression of pro inflammatory cytokines in mouse peritoneal tissue (MPT). After C57BL/6 mice were inoculated with abscess-forming mixture containing B. fragilis in the presence or absence of E. coli, RNA was extracted from MPT. Expression of interleukin (IL)-$1{\alpha}$ and tumor necrosis factor $(TNF){\alpha}$ mRNA was assessed using RT-PCR and standard RNA. Each cytokine protein was also measured by ELISA. The co-inoculation of E. coli into mouse peritoneal cavity advanced the onset of abscess development by B. fragilis infection. When mouse was co-infected with E. coli and B. fragilis intraperitoneally, there was a synergistic increase in the expression of IL-$1{\alpha}$ and $TNF{\alpha}$ mRNA in MPT and this was paralleled by increased cytokine protein secretion. Mixed inoculation of heat-killed E. coli and B. fragilis did not cause a synergistic increase in those cytokine mRNA expression. These results suggest that enteric bacteria may significantly affect proinflammatory cytokine signal produced by host peritoneal cavity in response to B. fragilis infection.

• Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.487-490
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• 2014

A pagurid hermit crab Catapaguroides fragilis was collected in Jeju Island, and described as new to the Korean fauna. It is the first member of the genus Catapaguroides known from Korea. Morphological descriptions of C. fragilis are presented with illustrations.

• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.86-90
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• 2000

We have earlier reported on the cloning and identification of bft-k from an enterotoxigenic strain of Bacteroides fragilis 419, which was isolated from the blood of a Korean patient who suffered from systemic infections [4,5]. The bft-k gene encodes a 397-amino-acids metalloprotease enterotoxin, and the protein has been identified as a new isoform of B. fragilis enterotoxins (BFTs), which are cytopathic to intestinal epithelial cells to induce fluid secretion and tissue damage in ligated intestinal loops [4, 6, 18, 20]. This report describes the cloning and sequencing of the enterotoxin pahogenicity islet of B. fragilis 419 which contains the bft-k gene. the cloned enterotoxin pathogenicity islet was found to have 6,045 bp in length and to contain 120bp direct repeats near its end. In the pathogenicity islet, in addition to the BFR-K, two putative open reading frames (ORFs) were identified; (1) the t-3 gene encoding a 396-amino-acids protein of a putative metalloprotease; (2) the third gene encoding an ORF of a 59-amino-acids protein, whose function has not yet beenn characterized. The expression of the t-3 gene in B. fragilis 419 was verified by western blot analysis.

• Journal of Aquaculture
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• v.13 no.1
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• pp.55-62
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• 2000

A 10-week feeding trial was conducted to investigate the effects of several yeasts with or without chemical treatment (protoplasted) in formulated diets on growth and body composition of juvenile abalone(Haliotis discus hanai). There replicate groups of the abalone average weighing 210 mg were fed one of eight isonitrogenous (30%) and isolipidic (4.4%) diets containing 3% Kluyveromyces fragilis protoplasted K. fragilis Candida utilis protoplasted C. utilis, Saccharomyces cerevisiae protoplasted S. cerevisiae or brewer's yeast. In addition these formulated diets were compared with commercial diet. Survival rate and proximate analysis of soft whole body of abalone were not significantly affected by the different dietary yeasts and commercial diet (P>0.05) Body weight gain and soft body weight control diet and diets containing S. cerevisiae or brewer's yeast (P<0.05) Shell length of abalone fed yeast and commercial diet (P<0.05) Th results suggest that protoplasted K. fragilis as an additive in this formulated diet can improve weight gain of abalone.

• The Journal of the Korean Society for Microbiology
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• v.21 no.4
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• pp.481-485
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• 1986

Six strains of Bacteroides fragilis group were isolated from clinical specimens, and these isolates were classified by the resistance to bile and kanamycin, and by catalase and indole reaction. Of 6 strains, 4 strains were belonged to B. fragilis and 2 were B. uniformis. Among 6 strains, only 2 of B. fragilis harbored plasmids. But these plasmid showed no correlation with phenotypic expression. There were some differences in susceptibility to 23 ${\beta}$-lactam antibiotics, also, marked susceptibility differences were found between 2 species, so these results may be contributed to the treatment of infection due to this micro-organism and the identification of these species.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.518-525
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• 1988

Lactobacillus casei IFO 3012 and Kluyveromyces fragilis(KFCC 35458) were cultured together in Soymilk to investigate the growth characteristics and the conditions suitable for acid Production. L. casei produced more amount of acid rapidly when cultured with K. fragilis in soymilk than when cultured singly. The optimum conditions for acid production by the mixed cultures of L. casei and K. fragilis were achieved with a temperature of $35-37^{\circ}C$, a 1:5-1:9(O.D 660) ratio of L. casei to K. fragilis at inoculum, a 1.0 level of sucrose fortification or a 2.0% level of skim milk powder fortification and a culture time of 24hr. Under these conditions the amounts of acid produced by the single culture of L. casei and the mixed cultures with K. fragilis were 0.31% and 0.44% in soymilk, 0.43% and 0.97%, respectively, in soymilk fortified with 1.0% level of sucrose. These indicate that the amount of acid produced by mixed cultures is about 1.42 fold greater in soymilk and about 2.26 fold greater in soymilk fortified with 1.0% level of sucrose than that produced by the single culture of L. casei. The amount of acid produced in soymilk fortified with 2.0% level of skim milk powder was 1.0 level for both of the single culture of L. casei and the mixed cultures of L. casei and K. fragilis after 24hr incubation. In soymilk fortified with skim milk power less than 1.5 the mixed culture with K. fragilis showed higher content of acid than the single culture of L. casei only.

• Korean Journal of Food Science and Technology
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• v.19 no.3
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• pp.263-272
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• 1987

Lactobacillus bulgaricus (KFCC 35463) and Kluyveromyres fragilis (KFCC 35458) were inoculated together in soymilk, and then growth characteristics, acid production and the conditions suitable for acid production were investigated. L. bulgaricus produced more acid and the rate of acid production was more rapid when this organism was incubated with K. fragilis in soymilk than when it was incubated singly. Studying the conditions suitable for acid production in soymilk, optimum acid production by the mixed cultures of L. bulgaricus and K. fragilis was achieved with a temperature of $35{\sim}37^{\circ}C$, a 1:2 (O.D.660) ratio of L. bulgaricus to K. fragilis at inoculum, a 1.0% level of sucrose fortification or a 1.5% level of skim milk powder fortification and a culture time of 24hr. Under these conditions the amount of acid produced by the single culture of L. bulgaricus and the mixed cultures of L. bulgaricus and K. fragilis were 0.14% and 0.41%, respectively, in soymilk, 0.13% and 0.70%, respectively, in soymilk fortified with 1.0% level of sucrose. These indicate that the amount of acid produced by mixed cultures is about 2.9-fold greater in soymilk and about 5.4-fold greater in soymilk fortified with 1.0% level of sucrose than that produced by the single culture of L. bulgaricus. The amount of acid produced in soymilk fortified with 1.5% level of skim milk powder was 0.84% level for both of the single culture of L. bulgaricus and the mixed cultures of L. bulgaricus and K. fragilis after 24hr incubation. However, the amount of acid produced by the mixed culture with K. fragilis was greater than that produced by the single culture of L. bulgaricus onlv in soymilk fortified with lower levels of skim milk powder than 1.5%.

• Journal of Microbiology and Biotechnology
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• v.30 no.3
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• pp.368-377
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• 2020

Enterotoxigenic Bacteroides fragilis (ETBF) is the main pathogen causing severe inflammatory diseases and colorectal cancer. Its biofilm plays a key role in the development of colorectal cancer. The objective of this study was to determine the antagonistic effects of cell-free supernatants (CFS) derived from Clostridium butyricum against the growth and biofilm of ETBF. Our data showed that C. butyricum CFS inhibited the growth of B. fragilis in planktonic culture. In addition, C. butyricum CFS exhibited an antibiofilm effect by inhibiting biofilm development, disassembling preformed biofilms and reducing the metabolic activity of cells in biofilms. Using confocal laser scanning microscopy, we found that C. butyricum CFS significantly suppressed the proteins and extracellular nucleic acids among the basic biofilm components. Furthermore, C. butyricum CFS significantly downregulated the expression of virulence- and efflux pump-related genes including ompA and bmeB3 in B. fragilis. Our findings suggest that C. butyricum can be used as biotherapeutic agent by inhibiting the growth and biofilm of ETBF.

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.287-292
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• 1988

The interaction between Lactobacillus acidophilus and Kluyveromyces fragilis on the utilization of amino acids in soymilk was investigated. K. fragilis assimilated relatively well various amino acids such as Met., ILe., Phe., Leu., Thr., Lys., Val., Arg., Tyr., Ser., Asp., Ala. and Glu. that existed only in trace amounts in soymilk. K. fragilis did not utilized Gly., while hi accumulated His. L. acidophilus hydrolyzed soyprotein to liberate various amino acids. Among various amino acids, it utilized Met., ILe., Thr., Tyr., Ser., Val. and His. as growth factors and accumulated Leu., Phe., Lys., Arg., Glu., Asp. and Ala. among the essential amino acids required by K. fragilis and Gly. These results implied that K. fragilis grew on amino acids that existed only in trace amounts in soymilk, but it's growth was stimulated by amino acids such as Leu., Phe., Lys., Arg., Glu., Asp. and Ala. ac-cumulated by L. acidophilus.