• Asian-Australasian Journal of Animal Sciences
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• v.32 no.10
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• pp.1580-1590
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• 2019

Objective: The aims of this study were to select one strain of Lactobacillus plantarum (L. plantarum) for a potential indigenous safe starter culture with low level antibiotic resistant and low biogenic amine production and evaluate its effect on biogenic amines reduction in Moo som. Methods: Three strains of indigenous L. plantarum starter culture (KL101, KL102, and KL103) were selected based on their safety including antibiotic resistance and decarboxylase activity, and fermentation property as compared with a commercial starter culture (L. plantarum TISIR543). Subsequently, the effect of the selected indigenous safe starter culture on biogenic amines formation during Moo som fermentation was studied. Results: KL102 and TISIR 543 were susceptible to penicillin G, tetracycline, chloramphenicol, erythromycin, gentamycin, streptomycin, vancomycin, ciprofloxacin and trimethoprim (MIC90 ranging from 0.25 to $4{\mu}g/mL$). All strains were negative amino acid-decarboxylase for lysis of biogenic amines in screening medium. For fermentation in Moo som broth, a relatively high maximum growth rate of KL102 and TISIR543 resulted in a generation time than in the other strains (p<0.05). These strain counts were constant during the end of fermentation. Similarly, KL102 or TISIR543 addition supported increases of lactic acid bacterial count and total acidity in Moo som fermentation. For biogenic amine reduction, tyramine, putrescine, histamine and spermine contents in Moo som decreased significantly by the addition KL102 during 1 d of fermentation (p<0.05). In final product, histamine, spermine and tryptamine contents in Moo som inoculated with KL102 were lower amount those with TISIR543 (p<0.05). Conclusion: KL102 was a suitable starter culture to reduce the biogenic amine formation in Moo som.

• Journal of Species Research
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• v.7 no.1
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• pp.9-12
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• 2018

In 2016, as part of a larger effort to discover indigenous prokaryotic species in Korea, we isolated the family Deinococcaceae and Planctomycetaceae as unrecorded bacterial species. From the high 16S rRNA gene sequence similarity (>98.5%) and formation of a robust phylogenetic clade with known species, it was determined that each strain was a distinct bacterial species. There are no official reports that these two species have been described in Korea; therefore, the bacterial strains of Deinococcus and Blastopirellula are described for the first time in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, and isolation sources are also described in the species description section.

• Journal of Species Research
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• v.5 no.1
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• pp.166-178
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• 2016

An outcome of the study to discover indigenous prokaryotic species in Korea, a total of 26 bacterial species assigned to the classes Bacteroidetes and Firmicutes were isolated from diverse environmental samples collected from soil, tidal flat, freshwater, seawater, wetland, plant roots, and fermented foods. From the high 16S rRNA gene sequence similarity (>99.0%) and formation of a robust phylogenetic clade with the closest species, it was determined that each strain belonged to each independent and predefined bacterial species. There is no official report that these 26 species have been described in Korea; therefore 14 strains for the order Flavobacteriales and two strains for the order Cytophagales were assigned to the class Bacteroidetes, and 8 strains for the order Bacillales and 4 strains for the order Lactobacillales were assigned to the class Firmicutes are reported for new bacterial species found in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are also described in the species description section.

• Journal of Species Research
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• v.7 no.2
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• pp.97-103
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• 2018

In 2016, as a subset study to discover indigenous prokaryotic species in Korea, a total of 15 bacterial strains were isolated and assigned to the class Betaproteobacteria. From the high 16S rRNA gene sequence similarity (>98.8%) and formation of a robust phylogenetic clade with the closest species, it was determined that each strain belonged to each independent and predefined bacterial species. There is no official report that these 15 species have been described in Korea; therefore, 1 strain of the Aquitalea, 5 strains of the Paraburkholderia, 2 strains of the Comamonas, 1 strain of the Cupriavidus, 1 strain of the Diaphorobacter, 2 strains of the Hydrogenophaga, 1 strain of the Iodobacter, 1 strain of the Massilia and 1 strain of the Rhodoferax within the Betaproteobacteria are described for unreported bacterial species in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, and isolation sources are also described in the species description section.

• Journal of Microbiology and Biotechnology
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• v.20 no.1
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• pp.153-160
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• 2010

The present study was carried out for the isolation of bacteriocin-producing enterococci from indigenous sources. Gram-positive enterococci are known for having the ability to produce enterocins with good antimicrobial potential. A total of 34 strains were isolated from processed dairy products of Pakistan and seven out of them were found to be member of genus Enterococcus on selective enumeration. Biochemical and molecular characterization revealed that four of these isolates (IJ-03, IJ-07, IJ-11, and IJ-12) were Enterococcus faecalis and three (IJ-06, IJ-21, and IJ-31) were Enterococcus faecium. Local processed cheese was the source of all enterococcal isolates, except E. faecium IJ-21 and IJ-31, which were isolated from indigenous yoghurt and butter samples, respectively. Bacterial isolates were sensitive to commonly used antibiotics except methicillin and kanamycin. They also lacked critical virulence determinants, mainly cytolysin (cyl), gelatinase (gel), enterococcal surface protein (esp), and vancomycin resistance (vanA and vanB). Polymerase chain reaction amplification identified that enterocin A and P genes were present in the genome of E. faecium IJ-06 and IJ-21, whereas the E. faecium IJ-31 genome showed only enterocin P genes. No amplification was observed for genes that corresponded with the enterocins 31, AS-48, L50A, and L50B, and ent 1071A and 1071B. There were no signals of amplification found for E. faecalis IJ-11, indicating that the antimicrobial activity was because of an enterocin different from those checked by PCR. Hence, the indigenous bacterial isolates have great potential for bacteriocin production and they had antibacterial activity against a variety of closely related species.

• Journal of Species Research
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• v.12 no.2
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• pp.165-173
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• 2023

Bacterial communities inhabiting islands play a vital role in the functioning and formation of a unique, isolated ecosystem. Nevertheless, there has been a lack of systematic research on the indigenous microbiological resources of the islands in Korea. To excavate microbial resources for further studies on the metabolism and biotechnological potential, a standard dilution plating was applied to coastal seawater samples collected from islands along the west coast of the Korean Peninsula, including Deokjeokdo, Baengnyeongdo, and Daebudo in 2022. A total of 2,007 bacterial strains were isolated from the samples as single colonies and identified using 16S rRNA gene sequence analyses. A total of 20 strains, with ≥98.7% 16S rRNA gene sequence similarity to bacterial species having validly published names but not reported in Korea, were designated as unrecorded bacterial species in Korea. The unrecorded bacterial strains were phylogenetically diverse and belonged to four phyla, five classes, 12 orders, 17 families, and 18 genera. The unreported species were assigned to Algimonas, Amylibacter, Notoacmeibacter, Roseibium, and Terasakiella of the class Alphaproteobacteria; Alteromonas, Congregibacter, Marinagarivorans, Marinicella, Oceanospirillum, Psychromonas, Thalassotalea, Umboniibacter, and Vibrio of the class Gammaproteobacteria; Lutibacter and Owenweeksia of the class Flavobacteriia; Paenibacillus of the class Bacilli; and Pelagicoccus of the class Opitutae. The taxonomic characteristics of the unreported species, including morphology, biochemistry, and phylogenetic position are provided in detail.

• Journal of Species Research
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• v.12 no.spc2
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• pp.15-22
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• 2023

During a comprehensive investigation of indigenous prokaryotic species in Korea, 20 and one bacterial strains assigned to the phyla Bacillota and Verrucomicrobiota, respectively, were isolated from diverse environmental habitats, including soil, mud, tidal flat, seawater, sand, sediment, brackish water, and healthy human urine. Based on their high 16S rRNA gene sequence similarities (>98.7%) and the formation of robust phylogenetic clades with their closest related reported species, each strain was assigned to an independent and predefined bacterial species. Since there were no published or official reports regarding these 21 isolates in Korea, they - 20 species of four families in two orders of the phylum Bacillota and one species of the phylum Verrucomicrobiota - have been reported as unrecorded species in Korea. In addition, Gram staining, colony and cell morphology, basic biochemical characteristic, isolation source, and strain ID of each species are also described in the species description sections.

• Journal of Species Research
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• v.12 no.spc2
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• pp.23-32
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• 2023

During screening for indigenous prokaryotic species in Republic of Korea in 2021, a total of 21 bacterial strains assigned to the phylum Bacteroidota were isolated from a variety of environmental habitats including pine cone, seaweed, soil, sea sediment, brackish water and moss. Based on the 16S rRNA gene sequence similarity value of more than 98.7% and formation of a robust phylogenetic clade with the type strain of the closest bacterial species, it was found that the 21 strains belong to independent and recognized bacterial species. There has been no official report that the identified 21 species have been isolated in Republic of Korea up to date. Therefore, 16 species in six genera of two families in the order Flavobacteriales, two species in two genera of two families in the order Cytophagales, one species in one genus of one family in the order Chitinophagales and two species in one genus of one family in the order Sphingobacteriales are proposed as unrecorded species of the phylum Bacteroidota isolated in Republic of Korea. Their Gram reaction, colony and cell morphology, basic phenotypic characteristics, isolation source, taxonomic status, strain ID and other information are described in the species descriptions.

• Journal of Species Research
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• v.10 no.1
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• pp.23-45
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• 2021

For the collection of indigenous prokaryotic species in Korea, 77 strains within the phylum Actinobacteria were isolated from various environmental samples, fermented foods, animals and clinical specimens in 2019. Each strain showed high 16S rRNA gene sequence similarity (>98.8%) and formed a robust phylogenetic clade with actinobacterial species that were already defined and validated with nomenclature. There is no official description of these 77 bacterial species in Korea. The isolates were assigned to 77 species, 31 genera, 18 families, 14 orders and 2 classes of the phylum Actinobacteria. All the strains except one Coriobacteriia strain were affiliated within the class Actinomycetia. Among them, the orders Streptomycetales and Microbacteriales were predominant. A number of strains were isolated from forest soils, riverside soils, and ginseng cultivated soils. Twenty-nine strains were isolated from 'Protected Ecosystem and Scenery Areas'. Morphological properties, basic biochemical characteristics, isolation source and strain IDs are described in the species descriptions.

• Journal of Species Research
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• v.12 no.4
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• pp.374-414
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• 2023

As part of a comprehensive investigation of indigenous prokaryotic species in Republic of Korea in 2022, 156 bacterial strains were isolated from diverse environmental habitats. These strains were assigned to six phyla, namely Acidobacteriota, Deinococcota, Actinomycetota, Bacillota, Bacteroidota, and Pseudomonadota. Each strain was identified based on 16S rRNA gene sequence similarity (>98.7%) and the formation of robust phylogenetic clades with their closest reported species. Among isolates, there is one species belonging to the phylum Acidobacteriota, one species belonging to the phylum Deinococcota, 28 species belonging to the phylum Actinomycetota, 19 species belonging to the phylum Bacillota, 19 species belonging to the phylum Bacteroidota, and 88 species belonging to the phylum Pseudomonadota (comprising 34 species of the class Alphaproteobacteria, 20 species of the class Betaproteobacteria, and 34 species of the class Gammaproteobacteria). Based on 16S rRNA gene sequence analysis, each strain was assigned to independent and predefined bacterial species. Since there were no published or official reports regarding these 156 isolates in Republic of Korea, they are reported as unrecorded species in Republic of Korea. The Gram stain, colony and cell morphology, basic biochemical characteristic, isolation source, and strain ID of each species are described in the species descriptions.