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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Microbiology and Biotechnology Letters
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Journal DOI :
The Korean Society for Applied Microbiology and Biotechnology
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Volume & Issues
Volume 36, Issue 4 - Dec 2008
Volume 36, Issue 3 - Sep 2008
Volume 36, Issue 2 - Jun 2008
Volume 36, Issue 1 - Mar 2008
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Problems and Verification System of Probiotics as Livestock-environment Improving Agent Produced and Circulated
Lee, Eun-Young ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 87~95
Probiotics are live organisms that when administered in adequate amounts confer a health benefit on hosts. The administration of direct-fed microbials (DFM) such as lactobacilli and bacillus, may be a more direct approach to beneficially alter gastrointestinal microflora than altering dietary ingredients or supplementing with growth-promoting levels of antibiotics. It is apparent that microbes have an important influence on immune development and resistance to infection; that microbes are not static colonizers of our bodies, but are dynamic, symbiotic coresidents. And it can improve the surrounding environments; decrease the malodor caused by degrade the excrement. Recently, new paradigm such as environment protection and safe food have been settled. In domestic farm house, there is a great demand for probiotics as a substitute of antibiotics for the improvement of environmental quality and the production of a competitive goods. Probiotics circulated in a country have three categories: an animal medicine permitted by national veterinary research quarantine service (NVRQS), a support feed registered in city or country house, and not-registered goods. However, lots of unqualified goods were produced and circulated. And thus, it is in urgent need of evaluating the present situation and effect of probiotics. This study was conducted to evaluate the system of a probiotics as a livestock-environment improving agents for the alternation of antibiotics and quality control of it.
PCR-Based Detection of Lactic Acid Bacteria in Korean Fermented Vegetables with recA Gene Targeted Species-Specific Primers
Shim, Sang-Min ; Lee, Jong-Hoon ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 96~100
Diversity of lactic acid bacteria involved in 5 Korean fermented vegetables (Cot kimchi, Dongchimi, Baechu kimchi, Oisobagi, and Chonggak kimchi) was investigated using PCR-based method. PCR primer pairs targeted the recA gene were used for the detection of 7 species of lactic acid bacteria mainly found in kimchi and Lactobacillus acidophilus involved in dairy fermentation. Lactobacillus plantarum and Lactobacillus sakei were detected in all samples tested but Lactobacillus paraplantarum, Lactobacillus pentosus, and Lb. acidophilus were not detected. Lactobacillus brevis and Leuconostoc citreum were detected only from Baechu kimchi and Leuconostoc mesenteroides was detected from Got kimchi, Dongchimi, Baechu kimchi, and Oisobagi. The difference of detected species from fermented vegetables may be originated from the difference of main materials. Lb. plantarum and Lb. sakei are supposed to be broadly involved in Korean fermented vegetables.
Construction of A Bacteriocidal Yeast Producing Bacteriocin OR-7
Lee, Ok-Hee ; Jang, Min-Kyung ; Lee, Dong-Geun ; Lee, Jae-Hwa ; Ha, Jong-Myung ; Ha, Bae-Jin ; Ahn, Ik-Yong ; Cho, Dong-In ; Lee, Sang-Hyeon ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 101~105
In order to obtain yeast cells producing a bacteriocin OR-7, the 180 bp polynucleotide corresponding to the OR-7 gene including codons for start and stop was chemically synthesized and cloned into pAUR123, an yeast expression vector. Transformed yeast cells exhibited growth inhibition of Bacillus subtilis, Campylobacter jeuni, Escherichia coli and Pseudomonas aeruginosa. This result indicates that yeast cells producing OR-7 possess bacteriocidal properties against both Gram positive B. subtilis and Gram negative C. jejuni, E. coli and P. aeruginosa cells. The recombinant yeast strain constructed in this study can be applied in the food preservative or animal feed.
Isolation and Characterization of Kimchi Lactic Acid Bacteria Showing Anti-Helicobacter pylori Activity
Lee, Youl ; Chang, Hae-Choon ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 106~114
One bacterium, which showed strong antagonistic activity against H. pylori KCCM 41756, was isolated from kimchi. The strain NO1 was designated as Lactobacillus plantarum NO1 based on Gram staining, biochemical properties, and 16S rRNA gene sequencing. The culture medium
of Lb. plantarum NO1 reduced
the urease activity of H. pylori KCCM 41756. Lb. plantarum NO1 inhibited the binding of H. pylori to human gastric cancer cell line, AGS cells, by more than 33%. Lb. plantarum NO1 exhibited high viability (maintained initial viable cell count of
) in 0.05 M sodium phosphate buffer (pH 3.0) for 2 h, in artificial gastricjuice for 2 h and in 0.3%, 0.5% oxgall for 24 h. Hemolysis phenomena did not observed when Lb. plantarum NO1 was incubated in the blood agar media. We concluded that Lb. plantarum NO1 can be a good candidate as a probiotic, harboring anti-H. pylori activity.
Suppression of Bacterial Wilt with Bacillus subtilis SKU48-2 Strain
Kim, Ji-Tae ; Kim, Shin-Duk ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 115~120
Bacterial populations from the rhizosphere were obtained and the efficacy of the bacterial wilt suppression, root colonizing ability and resistance to three kinds of chemical pesticides were assayed. According to these results, SKU48-2 was selected as a potential biological agent to control the bacterial wilt caused by Ralstonia solanacearum. SKU48-2 strain at
inoculum was able to suppress the bacterial wilt up to 60% in greenhouse trials. Also, the resistance of SKU48-2 to chemical pesticides make possible to use in combination with chemical pesticides for the control of bacterial wilt. Three different powder formulations of SKU48-2 were developed. The shelf-life of powder formulations was effective up to 6 months of storage. Unformulated bacterial suspension could not be stored for 2 weeks, at which time cell viability was completely lost. According to 16S rDNA sequence data, the SKU48-2 stain was identified as Bacillus subtilis.
Potential Probiotic Properties of Lactobacillus johnsonii IDCC 9203 Isolated from Infant Feces
Lee, Seung-Hun ; Yang, Eun-Hee ; Kwon, Hyuk-Sang ; Kang, Jae-Hoon ; Kang, Byung-Hwa ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 121~127
A strain IDCC 9203 isolated from infant feces was identified as Lactobacillus johnsonii on the basis of 16S rDNA sequence analysis. L. johnsonii IDCC 9203 was highly resistant to acid (MRS broth at pH 2.3) and bile (MRS broth with 0.3% oxgall). The antibacterial activities of L. johnsonii IDCC 9203 was examined against Salmonella typhimurium KCTC 2054. The growth of S. typhimurium KCTC 2054 was inhibited by the cell-free culture supernatant (at pH 4.0) of L. johnsonii IDCC 9203 as well as by the respective control (MRS broth at pH 4.0). Antimicrobial effect against S. typhimurium KCTC 2054 of L. johnsonii IDCC 9203 was probably due to the lactic acid. By an in vitro cell adhesion model, L. johnsonii IDCC 9203 preincubated or coincubated with Caco-2 cells reduced the adhesion of S. typhimurium KCTC 2054 to Caco-2 cells by 74% or 47.1%, respectively. Also in an in vivo model, L. johnsonii IDCC 9203 was colonized in mice intestines which were disrupted by ampicillin treatment. Its proliferation in the mice intestines reduced abnormal salmonella growth from
feces as an indigenous level. The results obtained in this study suggest that L. johnsonii IDCC 9203 may be a potential probiotic strain.
Synthesis of L-threo-2,3-Dihydroxyphenylserine (L-threo-DOPS) by Thermostable L-Threonine Aldolase Expressed in Corynebacterium glutamicum R
Baik, Sang-Ho ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 128~134
In order to examine efficient L-threo-2,3-Dihydroxyphenylserine (L-threo-DOPS) synthesis process using whole cell biocatalyst, a thermostable L-threonine aldolase (L-TA), which cloned from Streptomyces coelicolor A3(2) and improved for stability, was expressed in a Corynebacterium glutamicum R strain. The constructed Corynebacterium expression vector, pCG-H44(1) successfully expressed L-TA in C. glutamicum R strain, but showed very low expression level. In order to improve the expression level, the expression vector named pCG-H44(2) was reconstructed by eliminating 1 nucleotide between SD sequence and start codon of L-TA. The pCG-H44(2) vector plasmid was able to overexpress L-TA approximately 3.2 times higher than pCG-H44(1) in C. glutamicum R strain (CGH-2). When the whole cell of CGH-2 was examined in a repeated batch system, L-threo-DOPS was successfully synthesized with a yield of 4.0 mg/ml and maintain synthesis rate constantly after 30 repeated batch reactions for 130 h.
Immunomodulating Activity of Salicornia herbacea Extract
Ryu, Deok-Seon ; Kim, Seon-Hee ; Lee, Dong-Seok ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 135~141
Immunomodulating effect of Salicornia herbacea extract on the mouse splenocytes was investigated. Crude S. herbacea polysaccharide extract (CSP) and other kinds of fine S. herbacea polysaccharides (SPI and SPII) were prepared from S. herbacea by hot water extraction and further ultrafiltration and gel filtration chromatography. In vitro experiment, the mouse splenocytes and separated T cells were treated with CSP, SPI or SPII (0.5, 1, 2, 4 mg/ml). In vivo experiment, three different S. herbacea extracts were orally administrated everyday for one week. For the basic data, body weight and physiological parameters such as organ weight and spleen index were observed. The proliferation of the cells was used as an index for immunemodulating activity and the effect of proliferation was evaluated using MTS assay. The CSP, SPI and SPII directly induced the proliferation of splenocytes and separated T cells in a dose-dependent manner. In results, the proliferation was more increased in the SPI and SPII treated cells than in the CSP treated cells. The best proliferation was shown in the splenocytes cultured with SPI at the concentration of 4 mg/ml for 24 hr. The proliferation of splenocytes and separated T-cells was higher (3.2 and 3.5 times, respectively) than the control. Moreover, when the mouse splenocytes were treated with mitogen, the efficient proliferation was shown in the splenocytes cultured with SPI. In conclusion, polysaccharides from S. herbacea showed a substantial immunomodulating activity in the mouse immune cells.
Antibiotic Resistances of Enterococcus Isolated from Salad and Sprout
Kang, Tae-Mi ; Cho, Sun-Kyung ; Park, Jong-Hyun ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 142~148
To evaluate the antibiotic resistance of Enterococcus from salad and sprout, Enterococcus were isolated and identified from 47 salad samples and 37 sprout samples, and then their antibiotic resistances were analyzed. Ninety five Enterococcus, 41 strains from salad and 54 strains from sprout, were ultimately isolated. The frequent Enterococcus in salad and sprout were E. gallinarum, E. faecalis, E. faecium, E. hirae, and E. avium. Minimum inhibitory concentrations of the isolates for vancomycin were below
, which were not high levels of resistance. All Enterococcus proved to be resistant to streptomycin and chloramphenicol. Twenty two percentage of the isolates were resistant to penicillin, however, almost the isolates were sensitive to tetracycline. Eighteen percentage of the isolates were resistant to erythromycin. All E. faecium and E. faecalis were found to be ampicillin-resistant, and seven E. faecalis and five E. faecium were resistant to rifampicin. Overall antibiotic resistances of Enterococcus isolates were relatively low and low resistance to vancomycin was similar to those evidenced by Enterococcus isolated from the other foods. Therefore, there may be no special risk from the antibiotics resistances of Enterococcus and especially vancomycin-resistant Enterococcus from the fresh-cut salads and the sprouts.
Engineering Hybrid Proteins by Modular Recombination and Evolutionary Optimization
Lee, Seung-Goo ; Rha, Eu-Gene ; Ha, Jae-Seok ; Lee, Jeong-Min ; Kim, Sun-Hwa ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 149~157
Many proteins consist of distinctive domains that can act independently or cooperatively to achieve a unique function. As these domains evolve from a naturally existing repertoire of functional domains, this implies that domain organization is an intrinsic element involved in building the complex structure and function of proteins. Thus, identifying functional domains would appear to be critical to the elucidation of questions related to protein evolution, folding, and the engineering of hybrid proteins for tai- lored applications. However, the simple application of "Lego-like assembly" to the engineering of hybrid proteins is an oversimplification, as many hybrid constructs lack structural stability, usually due to unfavorable domain contacts. Thus, directed evolution, along with computational studies, may help to engineer hybrid proteins with improved physico-chemical properties. Accordingly, this paper introduces several approaches to functional hybrid protein engineering that potentially can be used to create modulators of gene transcription and cell signaling, and novel biosensors to analyze biological functions in vivo.
Breeding of Yeast Strain with Starch Utilizing and Alcohol Fermenting Ability by Protoplast Fusion
Ju, Min-No ; Hong, Sung-Wook ; Kim, Kwan-Tae ; Yum, Sung-Kwan ; Kim, Gye-Won ; Chung, Kun-Sub ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 158~164
The fusants which contain starch utilizing ability and alcohol fermenting ability were developed by protoplast fusion of Saccharomyces cerevisiae KOY-1 and Saccharomyces diastaticus KCTC 1804. Sacharomyces cerevisiae KH-12 was obtained by haploid induction from Saccharomyces cerevisiae KOY-1. The auxotropic mutants of yeast were obtained by using an ethylmethane sulfonate (EMS). The frequency of protoplast formation in Saccharomyces cerevisiae KOY-1
and Saccharomyces diastaticus KCTC 1804
were 90.5% and 97.7%, respectively. The frequency of fusant formation was
for the regenerated protoplast and the 1,000 fusants were obtained. Fusant FA 776 was selected as a potential yeast which contain an alcohol fermenting ability in the starch medium. The genetic stability was 4.64% for 10 passages of generation. Fusant FA 776 produced 13mg/ml of alcohol in 24% starch medium and showed 1.86-fold higher alcohol fermenting ability than Saccharomyces diastaticus KCTC 1804.
Effect of Temperature and pH on the Biosorption of Heavy Metals by Exophiala sp.
Lim, Joung-Soo ; Lee, So-Jin ; Lee, Eun-Young ;
Microbiology and Biotechnology Letters, volume 36, issue 2, 2008, Pages 165~172
To find the optimum growth and metal removal condition of isolated strain LH2, effects of the environmental factors such as medium pH, growth temperature, and metal concentrations were investigated. Based on the 18S rDNA analysis, the isolated strain was identified to Exophiala sp. with 100% homology. Isolated strain Exophiala sp. LH2 showed maximum removal efficiency of metals at the shaking conditions of pH 7 and
. When the concentration of metal was under 200ppm, the specific metal removal velocity at pH 7 increased from 0.01 to 4.43 mg-metal
as the concentration of metal increased from 10 ppm to 200 ppm. When 200 ppm of each metal was contained in the culture medium adjusted with pH 7, metal removal efficiencies Cr, Cu, Ni, Pb and Zn were 99.28%, 97.67%, 91.94%, 99.77%, 99.61%, respectively.