• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.889-895
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• 2006

To investigate the antibiotic-resistant patterns and the gene types of extended-spectrum $\beta$-lactamase (ESBL)-producing Klebsiella pneumoniae, we collected 226 Klebsiella pneumoniae strains from three general hospitals with more than 500 beds in Busan, Korea from September 2004 to October 2005, The minimum inhibitory concentration (MIC) of antibiotics was measured using the Gram-negative susceptibility (GNS) cards of Vitek (Vitek system, Hazelwood Inc., MO, U.S.A.). Of the 226 K, pneumoniae isolates, 65 ESBL-producing K. pneumoniae strains were detected by the Vitek system and confirmed by the double-disk synergy test. TEM (Temoniera) type, SHV (sulfhydryl variable) type, and CTX-M (cefotaxime) type genes were detected by polymerase chain reaction. All 65 K. pneumoniae strains were resistant to ampicillin, cefazolin, cefepime, ceftriaxone, and aztreonam, and 83.0% of the organisms were resistant to ampicillin/sulbactam, 66.1% to tobramycin, 67.6% to piperacillin/tazobactam, 61.5% to ciprofloxacin, and 47.6% to trimethoprim/sulfamethoxazole, and 43.0% to gentamicin. TEM-type ESBLs (TEM-1 type, -52 type) were found in 64.6% (42 of 65) of the isolates, SHV-type ESBLs (SHV-2a type, -12 type, -28 type) in 70.7% (46 of 65) of isolates, and CTX-M-type ESBLS (CTX-M-15 type) in 45% (29 of 65) of isolates. Of the 65 ESBL-producing K. pneumoniae strains, two strains were found to harbor blaSHV-28, which were detected in Korea for the first time. Therefore, more investigation and research on SHV-28 are needed in order to prevent the ESBL type-producing K. pneumoniae from spreading resistance to oxyimino cephalosporin antibiotics.

• Korean Journal of Environmental Biology
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• v.20 no.1
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• pp.20-24
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• 2002

We have from water samples of Kwalim, Dochang, and Mulwang reservoirs in Kyonggi-Do, where cyanobacteria blooming occurred. Isolated microbes which have lytic activity for cyanobacteria. Water samples were smeared on the Anabaena cylindrica lawn and incubated in light chamber at $28^\circ{C}$, under 3000 lux for 13 days. A fungus having cyanobacterial lytic activity was isolated from the samples of Dochang reservoir. The isolate was identified as Cryptococcus laurentii by Vitek system. From the culture of the isolate, four major extracellular protein bands (29, 35.2, 40.9, 51.1 kDa) have been detected and the 29 kDa protein band was more thickly appeared in the culture with cyanobacteria.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.383-387
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• 1998

This study was undertaken with packed tofu products to serve as a basic source for sanitary control of tofu production by detecting spoilage bacteria in tofu from which are isolated, investigating heat-resistance and growth characteristics of spoilage bacteria. Isolated strains were confirmed as relevant strains in tofu spoilage, and Strain No. Tl, T2 show 92% probability to be Enterobacter amnigenus, and 96% to be Flavobacterium indologenes according to the result of identifYing strains by using Vitek system. Both strains had high viability at $35^{\circ}C$, pH 6.5. In the heat-resistance test of isolated strains, Enterobacter amnigenus Tl was treated for 2 mins, the number remained 56.3% of the initial number at $60^{\circ}C$, 37.8% at $70^{\circ}C$, 34.0% at $80^{\circ}C$ and 22.2% at $90^{\circ}C$, and Flavobacterium indologenes T2 was treated for 2 mins, the number remained 74.8% of the initial number at $60^{\circ}C$, 65.7% at $70^{\circ}C$, 37.8% at $80^{\circ}C$ and 9.3% at 90^{\circ}C$.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.11-15
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• 2008

In searching for yeast to be utilized as biocontrol agents, a single yeast strain was isolated from Camellia sinensis based on its morphological, cultural, physiological, and biochemical properties, as well as by molecular techniques. This single strain was pink to red in color and designated as strain JY-1. The effects of temperature, pH, NaCl concentration, and ethanol concentration on the growth of the JY-l strain were examined for the JY-1. Growth occurred at temperatures ranging from 20 to $35^{\circ}C$, and between pH 3.0 and 12.0, with optimal growth at $25-30^{\circ}C$ and pH 5.0. The yeast also grew in the presence of 0-2% (w/v) NaCl and 0-4% (v/v) EtOH. The isolate was further classified based on biochemical characteristics using the VITEK system. The biochemical data obtained using this system were similar to those of Rhodotorula glutinis/Rhodotorula mucilaginosa (exhibiting a 93% matching level). Molecular phylogenetic analysis based on l8S rDNA sequences indicated that the yeast represented a basidiomycetous species, and its highest degree of sequence similarity was with Rhodosporidium azoricum, strain JCM11251 (99%).

• Journal of Mushroom
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• v.9 no.4
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• pp.180-185
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• 2011

Spent mushroom substrates (SMS) is a by-product remaining after a crop of mushrooms. About four surfactin-producing strains were isolated from SMS (Pleurotus eryngii). Among of them, one isolate, which designated to YJ07, potentially showed the antifungal activity against Aspergillus flavus and Aspergillus ochraceous producing mycotoxin on PDA medium. The biochemical characteristics of the strain YJ07 was similar with Bacillus subtilis and Bacillus amyloliquefaciens by Bacillus ID kit and VITEK 2 system. Comparative 16S rDNA gene sequence analysis of the strain YJ07 also showed that the strain YJ07 was most closely related to Bacillus amyloliquefaciens with sequence similarity of 99.5%. On the basis of their biochemical characteristics and phylogenetic distinctiveness, the strain YJ07 was classified within the genus Bacillus as Bacillus amyloliquefaciens YJ07. The antifungal compound from B. amyloliquefaciens YJ07 was similar to lipopeptide surfactin from Bacillus subtilis by TLC and HPLC analysis.

• Journal of Life Science
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• v.21 no.10
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• pp.1481-1486
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• 2011

Spent mushroom substrate (SMS) is a by-product remained after a crop of mushrooms. About seven thermophilic strains were isolated from SMS (Flammulina velvtipes). Among them, one isolate, designated UJ03, showed the antifungal activity against Aspergillus flavus and Aspergillus ochraceous producing mycotoxin on PDA medium, potentially. The strain UJ03 produced cellulase and xylanase as extracellular hydrolases. The strain UJ03 was identified as a member of the genus Bacillus by biochemical characteristics using Bacillus ID kit and VITEK 2 system. Comparative 16S rDNA gene sequence analysis showed that strain UJ03 formed a distinct phylogenetic tree within the genus Bacillus and was most closely related to Bacillus amyloliquefaciens with sequence similarity of 98.9%. On the basis of its physiological properties, biochemical characteristics and phylogenetic distinctiveness, strain UJ03 was classified within the genus Bacillus, for which the name Bacillus sp. UJ03 is proposed. The antifungal compound from Bacillus sp. UJ03 was similar to lipopeptide iturin A of Bacillus sp.

• Korean Journal of Microbiology
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• v.35 no.4
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• pp.296-301
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• 1999

A Bacillus strain from Korean soil was isolated and identified to be Bacillus licheniformis B1 through various biochemical tests, VITEK, and MIDI system analysis. The strain produced extracellular amylase and protease. Whether or not the strain can perform Chungkookjang fermentation with autoclaved soybean and Kanjang fermentation was determined in this study. In Chungkookjang fermentation, browining materials of strong anti-oxidant increased 8-fold, and 2-fold in Kanjang, compared with initiation material for fermentation. Maximal protease activity in Chungkookjang was observed one day after inoculation. Protease activities in Kanjang decreased to the half, and then maintained constant values during fermentation, probably due to the inhibitory effect of salt on protease activities. High molecular mass of nucleic acids was identified in Chungkookjang and Kanjang. Since the nucleic acids were not observed in autoclaved soybean, they seem to be originated from B. licheniformis B1. This study demonstrated successive fermentation of Chungkookjang and Kanjang by B. licheniformis B1 isolated from nature, and suggested possible development of food rich in browing and nucleic acids.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.836-840
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• 2011

In order to isolate thermophilic compost-promoting bacteria with high activity of cellulase and xylanase, spent mushroom substrates with sawdust were collected from mushroom cultivation farm, Jinju, Gyeongnam in Korea. Among of the isolates, one strain, designated SJ21 was selected by agar diffusion method. The strain SJ21 was identified as members of the Bacillus lincheniformis by biochemical characteristics using Bacillus ID kit and VITEK 2 system. Comparative 16S rDNA gene sequence analysis showed that strain SJ21 formed a distinct phylogenetic tree within the genus Bacillus and was most closely related to Bacillus subtilis with 16S rDNA gene sequence similarity of 99%. On the basis of its physiological properties, biochemical characteristics and phylogenetic distinctiveness, strain SJ21 was classified within the genus Bacillus, for which the name Bacillus sp. SJ21 is proposed. The cellulase and xylanase activity of Bacillus sp. SJ21 was slightly increased according to bacterial population from exponential phase to stationary phase in growth curve for Bacillus sp. SJ21.

• Journal of Life Science
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• v.20 no.8
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• pp.1214-1220
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• 2010

Imipenem-resistant bacteria were isolated from clinical specimens taken from hospitalized patients in Suncheon, Korea. Fifty-four isolates were phylogenetically analyzed based on 16S rRNA gene and gyrB gene sequence comparisons. Isolates were affiliated with Pseudomonas aeruginosa (30 strains; 55.6%), Acinetobacter baumannii (21; 38.9%), Enterobacter hormaechei (2) and Pseudomonas putida (2). Twenty-two isolates produced metallo-$\beta$-lactamase (MBL); 12 Acinetobacter baumannii strains, 7 Pseudomonas aeruginosa strains, 2 P. putida strains and 1 Enterobacter hormaechei strain. Antibiotic susceptibility of the isolates was determined using the disc diffusion method and Vitek system. Strains producing metallo-$\beta$-lactamase (type IMP & VIM) were more resistant to antibiotics ceftazidime, aztreonam, amikacin and gentamicin than to strains producing OXA and SHV type of $\beta$-lactamase.

• Microbiology and Biotechnology Letters
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• v.50 no.1
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• pp.147-156
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• 2022

Urinary tract infections (UTIs) are one of the most common infections in different age groups, including children. Bacteria are the main etiological agents of UTIs. The aim of the present study was to isolate, identify, and determine the antibiotic susceptibility of bacteria isolated from children with UTIs from Baghdad, Iraq. Three hundred and two urine samples were collected from children aged 6 months to 12 years. The samples were cultured on blood agar and MacConkey agar. The selected colonies were subjected to biochemical tests and antibiotic susceptibility analysis using the Vitek^® 2 Compact automated microbial identification system. In this sample, 299 bacteria were identified, of which, 267 were gram-negative bacteria, and 32 were gram-positive bacteria. Escherichia coli (56%) was the most commonly isolated gram-negative bacteria, followed by Pseudomonas aeruginosa (14%), Enterobacter spp. (10.48%), Klebsiella pneumoniae (9.36%), Proteus spp. (7.8%), Acinetobacter baumannii (1.5%), and Morganella morganii (0.37%). Enterococcus faecalis (62.5%) was the most commonly detected gram-positive bacteria, followed by Staphylococcus aureus (37.5%). E. coli and P. aeruginosa were the most antibiotic-resistant bacteria. Among the tested antibiotics, meropenem showed 100% sensitivity, followed by imipenem (97.4%), amikacin (91.8%), and tobramycin (83.5%). In contrast, the high frequencies of resistance were observed with cefixime (93.2%), cefotaxime (78.7%), and ceftriaxone/cefotaxime (71.2%). In conclusion, carbapenems and aminoglycosides are highly recommended for the empirical treatment of UTIs, while, Quinolones, penicillins, and cephalosporins are not suggested. Frequent antibiotics susceptibility testing are warranted to determine the resistance pattern of UTI bacteria.