• Food Science of Animal Resources
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• v.35 no.5
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• pp.615-621
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• 2015

Lactobacillus plantarum FH185 was isolated from the feces of healthy adults. In our previous study, L. plantarum FH185 was demonstrated that it has anti-obesity effect in the in vitro and in vivo test. In order to determine its potential for use as a probiotic, we investigated the physiological characteristics of L. plantarum FH185. The optimum growth temperature of L. plantarum FH185 was 40℃. L. plantarum FH185 showed higher sensitivity to novobiocin in a comparison of fifteen different antibiotics and showed higher resistance to polymyxin B and vancomycin. It also showed higher β-galactosidase and N-acetyl-β-glucosaminidase activities. Moreover, it was comparatively tolerant to bile juice and acid, and inhibited the growths of Salmonella Typhimurium and Staphylococcus aureus with rates of 44.76% and 53.88%, respectively. It also showed high adhesion activity to HT-29 cells compared to L. rhamnosus GG.

• Journal of Life Science
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• v.10 no.3
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• pp.262-272
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• 2000

As a part of investigation for basic epidemiology of diarrheogenic disease, we attempted isolation of Escherichia coli from patients with diarrhea. Seven hundred and twenty-one strains of E. coli were isolated from 1,239 patients with diarrhea. Seasonal distribution of patient with diarrhea was shown the most high at August (18.2%). Age group distribution of patient was shown the most high at children (54.6%, 2 to 10 years old). The serotypes of 721 E. coli isolates were in order of serotype O44 (16.8%), O153 (8.6%), O1 (7.5%), O166(5.7%), O8 and O86a (4.7%), and O125 (4.6%). The supernates cultured 36 strains among 721 E. coli isolates were indicated cytotoxicity against monolayered Vero cells. All of the isolates were susceptible to amikacin. The isolates were resistant in order of novobiocin (99.0%), moxalactam (97.1%), carbenicillin (96.1%), tetracycline (90.4%), ampicillin (85.9%), gentamicin (84.0%), streptomycin (78.4%), cephalothin (46.6%) and polymyxin B (4.2%). In the antibiotic resistant patterns, 125 kinds of multiple resistance patterns of E. coli isolates were detected. The highest resistant pattern was ampicillin-carbenicillin-chloramphenicol-cephalothin-erythro-mycin- gentamicin-moxalactam-novobiocin-penicillin G-streptomycin-tobramycin-tetracycline-tri methoprim type (24.3%).

• Korean Journal of Food Science and Technology
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• v.48 no.4
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• pp.323-328
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• 2016

In this study, specific and rapid enrichment and growth conditions for the most important, classic non-O157 enterohemorrhagic Escherichia coli (EHEC) serogroups were assessed. Three enrichment broth types, namely, EC medium with MUG broth, BRILA broth, and mTSB broth with novobiocin, were compared to identify the optimum enrichment broth for EHEC isolation. Four kinds of selective media, namely, ENDO agar, Chromocult agar, TBX agar, and CHROMagar$^{TM}$ STEC medium, were compared to identify the optimum one for non-O157 EHEC isolation. The results suggested that incubation in EC medium with MUG broth at $42^{\circ}C$ for 20 h is optimum for the enrichment of non-O157 EHEC. TBX agar was identified to have the highest specificity among the tested media. Consequently, a combination of complementary selective media according to serotype must be considered for comprehensive isolation of specific EHEC.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.142-147
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• 1989

Six plasmids of B. thuringiensis serovar. kurstaki HD73 were detected, with approximate sizes of 7.4, 7.8, 8.1, 11.3, and 75 Kb, as well as a low copied plasmid of similar length to 75 Kb. Partially cured mutants from B. thuringiensis HD73 were obtained either by the treatment of the curing agent, ethidium bromide(0.02 $\mu\textrm{g}$/$m\ell$) or by spontaneous curing, Acrystalliferous mutants(Cry$^-$) were identified by microscopic observation and immunoblotting with polyclonal antibody against 133 KD deltaendotoxin of HD73. Ten Cry$^-$ mutants were found to be lack of 75 Kb plasmid. These results implicated that this plasmid was associated with delta-endotoxin production, After isolating the mutants, we streaked them on potato dextrose agar, spizizen casamino acid glucose, starch agar, and nutrient agar. Only on starch agar medium did morphologies of Cry$^-$ appear translucent and light greyish. On the other hand, the mutants of B. thuringiensis isolated from Korean soil, designated KBS722, were obtained by the treatment of novobiocin (3 $\mu\textrm{g}$/$m\ell$). Acrystalliferous mutants of KBS722 were less translucent than HD73 mutants' only on nutrient agar medium. Compared the plasmid profile of the mutants with delta-endotoxin production, the results seemed to indicate that the insecticidal protein gene of B. thuringiensis isolates KBS722 located on about 225 Kb plasmid DNA.

• Journal of Dairy Science and Biotechnology
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• v.31 no.2
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• pp.143-152
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• 2013

Aminobutyric acid (GABA), a major inhibitory neurotransmitter in the central nervous system of animals, has several physiological effects including anti-hypertensive, diuretic, tranquilizing, and anti-stress properties, in humans. The purpose of this study was to investigate Lactobacillus plantarum K74, which was isolated from kimchi and selected as a strain with a high ability to produce GABA, to develop a new starter culture for fermented milk production. L. plantarum K74 produced $134.52{\mu}g/mL$ GABA in MRS broth containing 1% MSG, $212.27{\mu}g/mL$ GABA in MRS broth containing 2% MSG, and $234.63{\mu}g/mL$ GABA in MRS broth containing 3% MSG. The optimum growth temperature of L. plantarum K74 was $34^{\circ}C$, reaching a pH of 4.4 after 18 hours of growth. L. plantarum K74 was most sensitive to novobiocin out of 16 different antibiotics tested, and was most resistant to kanamycin and polymyxin B. L. plantarum K74 did not produce ${\beta}$-glucuronidase, a carcinogenic enzyme, and was comparatively tolerant to bile juice and low pH. Furthermore, it displayed resistance to Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus at rates of 54.9%, 46.3%, and 0.7%, respectively.

• Korean Journal of Microbiology
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• v.50 no.3
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• pp.245-248
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• 2014

Pseudomonas syringae pv. actinidiae is the causal agent of bacterial canker in kiwifruit (genus Actinidia). Multilocus sequence analysis of seven housekeeping and 11 type III effector genes differentiated the virulent P. syringae pv. actinidiae isolates worldwide into three groups designated as Psa1-Psa3. In this work, a total of 12 P. syringae pv. Actinidiae strains, including three Psa1, three Psa2, three Psa3 strains isolated from Korea and three Psa3 strains from Italy, were compared based on their phenotypic properties. Strains with different geographic origins had unique growth patterns as demonstrated by growth rate at several temperatures; all tested strains exhibited maximum growth at temperatures below $22^{\circ}C$, while the growth of Psa3 strains was completely inhibited above $30^{\circ}C$. Psa3 strains isolated from Korea had longer lag phases than the Psa3 strains from Italy. The Psa2 strains were different from Psa1 and Psa3 strains in the API 20NE test, in which the Psa2 strains could not utilize potassium gluconate, capric acid and trisodium citrate. Psa3 strains isolated from Korea could hydrolyze esculin. The API ZYM test showed that ${\beta}$-glucosidase activity was detected only from Psa3 strains. The strains belonging to the three Psa groups differed with regard to their susceptibility to ampicillin, novobiocin, and oleandomycin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.927-932
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• 1994

A total of 34 Salmonella sp. an d25 Shigella sp. were isolated from 311 patients with diarrhea. The isolation rates of Salmonella sp. ad Shigella sp. were 10.9% and 8%, respectively. The serogroups of 34 Salmonella sp. were in order of group D(50%), group B(38.25), group E(8.8%) and group C 92, 9%0. the serogroups of 25 Shigella sp. were group D(96%) and group B(4%). Seasonal distribution of isolated Salmonella sp. and Shigella sp. were shown the most high at July, 17.65% and 64%, respectively. Age group distribution of isolated Salmonella sp. and Shigella sp. were shown the most high at twenties and thirties (23.5%), and teens(76%), respectively. The Salmonella isolates were resistant in order of prevalence use of streptomycin(SM) (100%), erythromycin (EM) and movobiocin (NB)(90.6%), penicillin G(PG) (65.6%) and cephalexin (CPX)(46.9%). the isolates of Shigella sp. were resistant in order of prevalence use of EM (95.8%), NB(91.7%), SM(87.5%). Eighteen kinds of resistant patterns of Salmonella ioslates were detected. The multiple resistance patterns of Shigella isolates were mostly SM, EM, NB type (79.2%). The minimum inhibitory concentration of Salmonella sp. and Shigella sp. and Shigella sp. isolated from patients with diarrhea were tabulated.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.295-303
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• 2006

To provide microbial information for the safety of agricultural production, the presence of enterotoxin genes and antibiotic susceptibility of 14 isolated Staphylococcus aureus (11.7%) strains were investigated using PCR-based methods and disk diffusion method, respectively. Among enterotoxin-encoding genes, sea was detected from two isolates (14.3%), sea and sed genes were co-detected from three isolates (21.4%), and sea, sed, and see genes in seven isolates (50.0%), whereas seb, sec, and tsst were not detected in any isolate. Nine (64.3%), eight (57.1%), six (42.9%), two (14.3%), and one (7.2%) isolates were resistant to penicillin, novobiocin, amphicillin, erythromycin and oxacillin, and doxycycline and kanamycin, respectively. Methicilline-resistant S. aureus was found in roller of B farm and in hydroponic solution of D farm.

• Journal of Microbiology and Biotechnology
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• v.13 no.4
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• pp.564-570
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• 2003

The antibacterial mechanism of enterobacter Salmonella typhimurium was studied. The rfa (Waa) gene cluster of S. typhimurium encodes the core oligosaccharide biosynthesis of lipopolysaccharide (LPS). Among the rfa gene cluster, we recently cloned the rfaE gene, which is involved in ADP-L-glycero-D-manno-heptose biosynthesis. The rfaE mutant synthesizes heptose-deficient LPS, which consists of only lipid A and 3-deoxy-D-manno-octulosonic acid (KDO), thus making an incomplete LPS and a rough phenotype mutant. S. typhimurium deep-rough mutants with the heptose region of the inner core show a reduced growth rate, sensitivity to high temperature, and hypersensitivity to hydrophobic antibiotics such as baicalin isolated from the medicinal herb of Scutellaria baicalensis Georgi. Thus, in this study, the cloned rfaE gene was added to the S. typhimurium rfaE mutant strain SL1102 (rfaE543), which makes heptose-deficient LPS and has a deep-rough phenotype. The complementation created a smooth phenotype in the SL1102 strain. The sensitivity of SL1102 to bacteriophages was also recovered to that of wild-type strain, indicating that LPS is used as the receptor for bacteriophage infection. The permeability barrier of SL1102 to hydrophobic antibiotics such as novobiocin and baicalin was restored to that of the wild-type, suggesting that antibiotic resistance of the wild-type strain is highly correlated with their LPS. Through an agar diffusion assay, the growth-inhibition activity of baicalin was fully observed in the mutant SL1102 strain. However, only a half of the inhibitory activity was detected in the rfaE complemented SL1102 strain. Furthermore, the LPS produced by the rfaE-complemented SL1102 strain was indistinguishable from LPS biosynthesis of smooth strains.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.147-156
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• 2014

The aim of this study was to investigate the physiological characteristics and anti-obesity effects of E. faecalis MD366 isolated from raw milk. E. faecalis MD366 inhibited lipase activity ($65.0{\pm}0.9%$) and differentiation of 3T3-L1 adipocytes ($27.4{\pm}1.4%$) at a concentration of $100{\mu}g/mL$ ($10^8CFU/g$ E. faecalis MD366). The optimum growth temperature of E. faecalis MD366 was $37^{\circ}C$. Among 16 tested antibiotics, E. faecalis MD366 demonstrated the highest sensitivity to novobiocin and the highest resistance to neomycin, kanamycin, and vancomycin. The strain also showed high acid phosphatase activity. Moreover, E. faecalis was relatively tolerant to bile juice and acid, and displayed high resistance to Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus (80.4%, 60.2%, and 65.4%, respectively). These results demonstrate that E. faecalis MD366 can be potentially used as a probiotic with anti-obesity effects.