• Applied Biological Chemistry
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• v.40 no.2
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• pp.101-106
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• 1997

A screening was performed to isolate the cellulose-producing microorganisms from vinegar in Korea. The isolated strain was identified as Acetobacter sp. with respect to physiological and biochemical characteristics and designated as Acetobacter CBI-2. Cellulose production of Acetobacter CBI-2 was equal with the well known cellulose-producing bacteria, A. xylinum. The result of separation on thin layer chromatography(TLC) was consistent with the degradation product of native cellulose. The presence of genes required for the cellulose biosynthesis in Acetobacter CBI-2 was confirmed by Southern hybridization.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.384-389
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• 2009

To isolate lactic acid bacteria having high exopolysaccharides (EPS) production ability, 50 strains were initially isolated from the sourdough. Twenty-one strains formed highly mucoid colonies on the sucrose agar medium, which are indicative of active EPS synthesis. DU-07, DU-10, DU-12, DU-19, and DU-21 produced $11.51{\pm}0.167$, $13.09{\pm}0.193$, $12.72{\pm}0.108$, $11.61{\pm}0.284$, and $13.32{\pm}0.094\;g/L$ EPS, respectively, in MRS medium. The isolated strains, DU-10, DU-12, and DU-21, were identified as Enterococcus flavescens, Enterococcus faecium, and Lactobacillus amylovorus, respectively, by using API 50CHL kit and determining partial sequences of their 16S rDNA. Especially, L. amylovorus DU-21 showed the highest production of EPS, as well as the highest inhibitory activities against pathogenic (p<0.05). Interestingly, the L. amylovorus DU-21 seem to be endemic to sourdough fermentations, as they have not been isolated from other environments.

• Korean Journal of Agricultural Science
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• v.37 no.2
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• pp.255-260
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• 2010

Rusty root, the browning disease on ginseng, decreases quality and value. Recent studies indicated that endophytic bacteria could be a possible cause of rusty root. Actinomycetes antagonistic to the rusty-root-causing bacteria were isolated from soil. Twenty nine out of 932-isolates of Actinomycetes from soil showed antibacterial activity against Agrobacterium tumefaciens and Pseudomonas veronii an endophytic isolate in ginseng. The strongest antibacterial strain(ATO4O104) was classified based on 16S rDNA sequence. The Actinomycetes strain, ATO4O104, isolated in soil of USA volcano national park was identified as Streptomyces adephospholyticus. To test plant toxicity, radish seeds were sprouted with the culture of S. adephospholyticus and it did not show any harmful effect. The butanol partition out of n-hexane, ethyl acetate, butanol, and water partions showed the highest antibacterial activity.

• Microbiology and Biotechnology Letters
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• v.50 no.1
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• pp.81-88
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• 2022

Acetic acid bacteria (AAB) are versatile organisms involved in the production of variety of fermented foods, such as vinegar and kombucha, and products of biotechnological relevance, such as bacterial cellulose. In the present study, Malatya apricot, a variety with protected designation of origin (PDO), and vinegar samples produced using various fruits were used to isolate AAB. The 19 AAB isolates obtained were typed using (GTG)5 fingerprinting, and the ones selected were identified by sequencing either 16S rDNA alone or in combination with 16S-23S rRNA internal transcribed spacer region or ligA gene. While all apricot isolates (n = 10) were Gluconobacter cerinus, vinegar isolates (n = 9) were composed of Komagataeibacter saccharivorans, Acetobacter syzygii, and possible two new species of AAB, Komagataeibacter sp., and Gluconobacter sp. (GTG)5 fingerprinting showed the presence of several genotypes of G. cerinus in the apricot samples. Screening for some technologically relevant properties, including thermotolerance, ethanol tolerance, and cellulose production capability, showed that all Komagataeibacter and some Gluconobacter isolates could tolerate the temperature of 35℃, and that vinegar isolates could tolerate up to 8% ethanol. One isolate, Komagataeibacter sp. GUS3 produced bacterial cellulose (1 g/l) and has the potential to be used for cellulose production.

• Journal of Dairy Science and Biotechnology
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• v.40 no.1
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• pp.15-22
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• 2022

This study evaluated the levels of D(-)-lactate and L(+)-lactate, and the ratio of D(-)-lactate to total lactate (D(-)-lactate + L(+)-lactate) of 15 lactic acid bacteria (LAB) using an enzymatic method. D(-)-lactate and L(+)-lactate levels in the LAB ranged from 0.31 to 13.9 mM and 0.76 to 39.3 mM, respectively, in Bifidobacterium sp.; 1.08 to 11.7 mM and 0.69-13.0 mM in Lactobacillus sp.; 0.72 to 20.3 mM and 0.98 to 32.3 mM in Leuconostoc sp., and 33.0 mM and 39.2 mM in Pediococcus acidilacti KCCM 11747. The ratio of the range of D(-)-lactic acid to total lactic acid was 28.98%-45.76% in Bifidobacterium sp., 41.18%-61.02% in Lactobacillus sp., 29.85%-42.36% in Leuconostoc sp., and 45.71% in P. acidilacti KCCM 11747. In the future, there is a need to test for D(-)-lactate in various fermented products to which different LAB have been added and study the screening of LAB used as probiotics that produce various concentrations of D(-)-lactate.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2001.11a
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• pp.143-143
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• 2001

• Archives of Pharmacal Research
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• v.24 no.1
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• pp.27-34
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• 2001

A series of 2-methylbenzimidazole incorporated to different heterocycles through ethyl or carbamoylethyl groups at position 1 of benzimidazole were synthesized. Also 3-(2-methylbenzimidazol-1-yl)propanoic acid hydrazide incorporated with semicarbazides and thiosemicarbazides were prepared. Moreover, the triazole 5e underwent Michael addition and alkylation reaction. Some of the newly synthesized compounds showed considerable antimicrobial activity against gram positive, negative bacteria and yeast.

• The Plant Pathology Journal
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• v.27 no.4
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• pp.333-341
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• 2011

Two antifungal bacteria were selected from forest soils during the screening of microorganisms antagonistic to Cylindrocarpon destructans, a cause of ginseng root rot. The antifungal bacteria were identified as Bacillus subtilis (I4) and B. amyloliquefaciens (yD16) based on physiological and cultural characteristics, the Biolog program, and 16S rRNA gene sequencing analyses. Antagonistic activity of both bacterial isolates to C. destructans increased with increasing temperature. More rapid starch hydrolytic activity of the bacteria was seen on starch agar at higher temperatures than at lower temperatures, and in the higher density inoculum treatment than in the lower density inoculum treatment. The bacterial isolates failed to colonize ginseng root the root tissues inoculated with the bacteria alone at an inoculum density of $1{\times}10^6$ cfu/ml, but succeeded in colonizing the root tissues co-inoculated with the bacteria and C. destructans. Scanning electron microscopy showed that the pathogen was damaged by the low-density inoculum treatment with the bacterial isolates as much as by the high-density inoculum treatment. Both bacterial isolates were more effective in reducing root rot when they were treated at a concentration of $1{\times}10^6$ cfu/ml than at $1{\times}10^8$ cfu/ml. Also, only the former treatment induced prominent wound periderm formation, related to structural defense against pathogen infection. The results suggest that the bacterial antagonists may have high potential as biocontrol agents against ginseng root rot at relatively low-inoculum concentrations.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.167-171
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• 1997

Methanol extracts from 25 seed samples belonging to the family Leguminosae were subjected to an in vitro screening for their growth-promoting and inhibitory activities towards Bifidobacterium adolescentis, B. longum, B. bifidum, and Lactobacillus casei, using spectrophotometric and paper disc agar diffusion methods under $O_2-free$ conditions, respectively. The responses varied with both bacterial strains and plant species. Among seed extracts, extracts from Glycine max (light-green color) and Arachis hypogaea (dark-brown) enhanced the growth of lactic acid bacteria in media with or without carbon sources, suggesting that bifidus factor(s) might be involved in the phenomenon. This growth-promoting effect was most pronounced with L. casei among lactic acid bacteria used. Additionally, all seed extracts did not adversely affect the growth of the lactic acid bacteria tested.

• Journal of Applied Biological Chemistry
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• v.63 no.2
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• pp.125-129
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• 2020

Environmental pollution caused by various heavy metals is a serious global problem. To solve this problem, microbial bioremediation of contaminated metals has developed rapidly as an effective strategy when physical and chemical techniques are not suitable. In this study, cadmium (Cd)-tolerant soil bacteria were isolated via artificial induction in laboratory conditions instead of screening bacteria naturally adapted to metal-contaminated soils. Wild-type (WT) bacteria grown in uncontaminated soils were artificially and sequentially adapted to gradually increasing Cd concentrations of up to 15 mM. The resultant cells, named Soil-CdR15, survived at a Cd concentration of 10 mM, whereas WT cells failed to survive with 4 mM Cd on solid media for 2 d. In liquid media containing Cd, the SoilCdR15 cells grew with 15 mM Cd for 7 d, whereas the WT cells could not grow with 5 mM Cd. Both Soil-CdR15 and WT cells removed approximately 35% of Cd at the same capacity from liquid media containing either 0.5 or 1.0 mM Cd over 2 d. In addition to Cd, the Soil-CdR15 cells showed increased resistance to nickel, zinc, and arsenic compared to WT cells. The Soil-CdR cells were identified as Burkholderia sp. by partial sequencing of 16S rRNA. The data presented in this study demonstrate that isolation of heavy metal-tolerant microorganisms via artificial induction in laboratory conditions is possible and may be useful for the application of the microorganisms for the bioremediation of heavy metals.