• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.497-502
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• 2002

Thirty-nine strains of Leuconostocs found to be tolerant to $10\%$ or more garlic were selected for further identification, by comparing their whole-cell protein pattern, 16S rRNA gene (first 530 bases) sequence, cellular fatty acid composition, and carbon source metabolism. Two isolates were Identified as Leuconostoc mesenteroides and 32 others as Leuconostoc citreum. Five other strains belonging to a cluster could not be allocated to the existing species. 16S rRNA gene sequence and cellular fatty acid composition of the unidentified bacteria exhibited close similarity with Leuconostoc argentinum. The unidentified isolates were not allocated to L. argentinum, because they formed polysaccharide from sucrose, while L. argentinum strains do not. Leuconostocs tolerant to high concentration of garlic were found predominantly on garlic surface, an extreme environment which is unfit for most of other microorganisms.

• Journal of Microbiology
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• v.39 no.1
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• pp.11-16
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• 2001

Tentative identification of Leuconostoc lactis IH23 isolated from kimchi (a fermented vegetable product) has been described previously with 16S rDNA sequencing (Choi, 1., M. Sc. Thesis Inha Univ.1999). This strain produced the slime identified as dextran based on IR, $\^$13/C- and $^1$H-NMR spectroscopic results. Further study proved that the isolate IH23 belongs to a homogeneous genetic group with L. lactis DSM 20202$\^$T/ and L. argentinum DSM 8581$\^$T/. The results showed DNA-DNA homology of 99-100%, 16S rDNA gene sequence similarity (97.7% ), and a phylogenetic relationship although L. argentinum DSM 8581$\^$T/ had lower homology (80-91%). These data indicate that L. argentinum DSM 8581$\^$T/ and the isolate IH23 belong to an identical species with L. lactis DSM 20202$\^$T/at the genetic level, although in carbohydrate fermentation, the isolate IH23 was mast closely related to L. argentinum DSM 8581$\^$T/ and quite different from L. lactis DSM 20202$\^$T/. Here we first report the isolation of consistent phenotypic variation in Leuconostoc lactis. We also emphasize that the nomenclature of subspecies needs to be differentiated into the three strains mentioned above in Leuconostoc lactis.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.416-419
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• 2005

Unknown bacterium isolated from garlic was characterized using phenotypic methods, phylogenetic analysis, DNA-DNA hybridization, and cultural methods. The strain was identified as typical leuconostoc; Gram-positive, non-sporeforming, heterofermentative, catalase-negative and spherical. Although its 16S rRNA gene sequence showed high homology to Leuconostoc argentinum DSM $8581^T$(99.8%), DNA-DNA hybridization experiments indicated it represents novel genomic species in the genus Leuconostoc. The garlic-specific leuconostoc was more resistant to antimicrobial activity of garlic compared to other common laboratory lactic acid bacteria, and was even stimulated by low concentrations (1-2%) of garlic extract supplemented in trypticase soy broth. Growth stimulation was concentration-dependent when tested with residual aqueous layer after solvent extraction of fresh whole garlic extract.