• Journal of Environmental Science International
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• v.12 no.9
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• pp.935-941
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• 2003

To investigate the interaction of bacteria and Microcystis isolated from a hypertrophic reservoir(Seo-Nakdong River), the response of five bacteria in relation to the different treatment of Microcystis and microcystin production by addition of dominant bacteria Staphylococcus sciuri were examined. Five bacteria (S. sciuri, S. capitis, S. epidermis, Pseudomonas aeruginosa and Aeromonas aimonicida) were identified from the reservoir. In the experiment of bacterial response, two types of bacterial growth pattern were observed. All bacteria showed active growth in heated Microcystis-added media. Especially, three species of bacteria (S. sciuri, S. capitis and P. aeruginosa) among them showed active growth in live Microcystis-added media. In Microcystis response, increase of microcystin production showed when dominant bacteria, S. sciuri was added.

• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.329-333
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• 1998

Cell wall (lactic acid bacteria-sonicated precipitate ; LAB-SP) and cytosoll(lactic acid bacteria-sonicated supernatant ; LAB-SS) fractions were prepared from kimchi fermenting lactic acid bacteria such as Leuconostoc mesenteroides, Lactobacillus brevis, Lactobacillus fermentum , Lactobacillus plantarum and Pediococcus acidilactici, with Lactobacillus acidophillus isolated from yogurt. Using the Ames mutagenicity test and SOS chormotest system, the antimutagenic acitivity of those cell fractions was studied . One hundered eighty $\mu$l of LAB-SP from lactic acid bacteria isolated from kimchi, excepting Pediococcus acidilactici, supressed the mutagenicity of 4-nitroquinoline-1-oxide(4-NQO) in Ames mutagenicity test and SOS chromotes system , by above 90% and 60% , respectively. LAB-SP from lactic acid bacteria also inhibited the mutagenicity mediated by 3-amino-1-methyl-5H-pyrido [4,3-b]indole (Trp-P-2). Lactobacillus fermentum, Lactobacillus plantarum, and Lactobacillus acidphillus had higher antimutagenicity against Trp-P-2). Lactobacillus fermentum , Lactobacillus plantarum , and Lactobacillus acidphillus had higher antimutagenicity against Trp-P-2 than the other lactic acid bacteria. However, LAB-SS of lactic acid bacteria did not show any mutagenic activity against 4-NQO in Ames mutagenicity test and SOS chromotest systems. On the mutagenicity of MEIQ and Trp-P-2 , LAB-SS of lactic acid bacteria from kimchi or dairy products exhibited a weaker inhibitory effect than LAB-SP of those bacteria. These results represent that, whether the lactic acid bacteria from kimchi are viable or nonviable, antimutagenic acitivity was still effective. We suggest that the strong, antimutaganic activity of lactic acid bacteria might be found in the cell wall fraction , rather than in the cytosol fraction.

• The Journal of the Korean Society for Microbiology
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• v.10 no.1
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• pp.19-24
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• 1975

Anaerobic bacteria are the major residents of human skin and mucous membrane. The importance, as opportunistic pathogens, of anaerobic bacteria are well recognized because of more population. with decreased defense against bacterial invasion due to chemotherapy, rediation therapy, extensive surgical operation etc. are dealt at hospitals. An analysis of the anaerobe isolation results at Yonsei University Medical Center during the January 1974-May 1975 period was made and the following results were obtained. 1) From 118 patients 146 strains of anaerobes were isolated. Among these 81.3% were nonsporforming anaerobes. Most frequently isolated anaerobes were Pc. asaccharolyticus, Ps. anaerobius, Ps. intermedius, B. fragilis and Cl. perfringens. 2) Anaerobes were frequently isolated from wound, female genital, intraabdominal, and pleuropulmonary specimens. Fewer anaerobes were isolated from blood, spinal fluid and liver specimens. 3) The ratio of anaerobe isolation to total bacteria isolation were; liver 66.7%, intraabdominal 33.3%, pleuropulmonary 28.9%, spinal fluid 5.0% and blood 4.2%. 4) Among the 118 anaerobe isolated patients, 48.3% yielded anaerobes only and rest of them yielded anaerobes together with aerobes. 5) Most of the gram-positive anaerobes were susceptible to the antibiotics tested. Exception was to tetracycline to which appreciable number showed resistance. It was noteworthy that only 48% of B. fragilis was susceptible to tetracycline.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.110-110
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• 2018

The purpose of this study was to evaluate the improved antioxidant activity of Aronia extract fermented by lactic acid bacteria isolated from fermented seafoods. Aronia fruits were collected from Sunchang, Chonbuk, South Korea. And these collected fruits were lyophilized for fermentation. For the selection of effective lactic acid bacteria useful for fermentation. Aronia fermented by lactic acid bacteria that isolated from fermented seafood was extracted with 60% ethanol. Antioxidant activity of Aronia extract was evaluated on the DPPH radical scavenging activity and total polyphenol contents were studied. To determine the optimal fermentation conditions, the changes of antioxidant efficacy was evaluated by controlling temperature (25, 30, 37, $40^{\circ}C$), Time (0~5 day) and inoculation dose of lactic acid bacteria (0.125~0.5ml). To confirm the antioxidative effect of Aronia fermented under optimal conditions, the DPPH & ABTS radical scavenging activity, total polyphenol & flavonoid contents were compared before and after fermentation were studied. 16 different kinds of lactic acid bacteria were isolated from fermented seafood, and of which antioxidant activity of Aronia fermented by Pediococcus pentosaceus B1 was maximum. Aronia fermentation at $37^{\circ}C$ was maximized when fermented for 3 days and fermentation time is decreased as the start inoculation amount of lactic acid bacteria increased. The degree of increase in antioxidant activity after Aronia fermentation is that DPPH & ABTS radical scavenging activity was increased about 27%, 20% and total polyphenols & flavonoids contents was increased about 12%, 15%. In the result of this experiment indicated that fermentation process enhances the antioxidant efficacy of Aronia.

• Journal of Microbiology
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• v.44 no.6
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• pp.694-698
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• 2006

Several marine bacterial strains were isolated from Undaria pinnatifida (Miyok in Korean). Sixty-six strains were isolated on R2A agar media at $10^{\circ}C$ and identified by a phylogenetic analysis of the 16S rRNA gene sequences. They were grouped into 10 different sequence types based on the initial sequence analysis of the 5' domain of the gene (approximately 500 bp). Full sequences of 16S rRNA gene, were obtained from one strain in each sequence type and the species-affiliation was determined using phylogenetic and sequence similarity analyses. The results of the analyses indicated that they were closely related to Psychrobacter aquimaris, P. celer, P. nivimaris, P. pulmonis, Psychromonas arctica or Bacillus psychrodurans. These bacteria are marine or psychrotrophic bacteria. Because the sporophytes of U. pinnatifida are cultured on the costal area during winter, the U. pinnatifida-associated bacteria appeared to grow at low temperatures. U. pinnatifida sporophytes can be a good source for the isolation of psychrotrophic bacteria.

• Journal of Microbiology and Biotechnology
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• v.34 no.3
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• pp.570-579
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• 2024

Root-nodule nitrogen-fixing bacteria are known for being specific to particular legumes. This study isolated the endophytic root-nodule bacteria from the nodules of legumes and examined them to determine whether they could be used to promote the formation of nodules in other legumes. Forty-six isolates were collected from five leguminous plants and screened for housekeeping (16S rRNA), nitrogen fixation (nifH), and nodulation (nodC) genes. Based on the 16S rRNA gene sequencing and phylogenetic analysis, the bacterial isolates WC15, WC16, WC24, and GM5 were identified as Rhizobium, Sphingomonas, Methylobacterium, and Bradyrhizobium, respectively. The four isolates were found to have the nifH gene, and the study confirmed that one isolate (GM5) had both the nifH and nodC genes. The Salkowski method was used to measure the isolated bacteria for their capacity to produce phytohormone indole acetic acid (IAA). Additional experiments were performed to examine the effect of the isolated bacteria on root morphology and nodulation. Among the four tested isolates, both WC24 and GM5 induced nodulation in Glycine max. The gene expression studies revealed that GM5 had a higher expression of the nifH gene. The existence and expression of the nitrogen-fixing genes implied that the tested strain had the ability to fix the atmospheric nitrogen. These findings demonstrated that a nitrogen-fixing bacterium, Methylobacterium (WC24), isolated from a Trifolium repens, induced the formation of root nodules in non-host leguminous plants (Glycine max). This suggested the potential application of these rhizobia as biofertilizer. Further studies are required to verify the N₂-fixing efficiency of the isolates.

• Microbiology and Biotechnology Letters
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• v.25 no.6
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• pp.617-622
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• 1997

This studies were carried out to investigate the physiological characteristics of lactic acid bacteria related to kimchi fermentation. 157 strains of lactic acid bacteria were isolated from home-made kimchi of Taegu district. 144 strains of isolated lactic bacteria showed resistance to artifical gastric juice and bile. Among isolated strains, fifteen strains were selected according to the growth characteristics. The selected strains survived for 24 hours in artifical bile after incubation for 3 hours in artificial gastric jucie (pH 2.5). Especially, three strains such as B-10, K-2, and F-3, showed little viable cell change for 3 hrs incubation in artifical gastric juice. The selected strains showed low viability in artificial gastric juice but high in artifical bile. The selected strains also showed significantly antimicrobial activities to pathogens such as Listeria monocytogenes, Escherichia coli, Bacillus subtili, Staphylococcus aureus and Vibrio parahaemolyticus. The fifteen selected strains were identified as Lactobacillus plantarum, Lactobacillus sake and Leuconostoc mesenteroides.

• Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.76-81
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• 2008

We isolated 1,916 strains of bacteria from gut and feces of abalone. The most active agarolytic bacterium, DAG-130, was identified from the gut of the abalone Haliotis gigantea. Of the bacteria harbored by both H. discus hannai and H. gigantea, 59% were agarolytic. There was no significant difference in the number of agarolytic bacteria isolated from abalone fed on the seaweeds Gelidium amansii, Laminaria japonica, or Undaria pinnatifida. Of the agarolytic bacteria, 72% were isolated from the guts of all sources tested while 43% came from the feces. The strain DAG-130 showed 100% identity with the bacterium Vibrio cyclotrophicus based on phylogenetic analysis of l6S rDNA. The bacterium produced monomers and oligomers from the agar substrate.

• Restorative Dentistry and Endodontics
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• v.14 no.1
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• pp.85-96
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• 1989

In the Infected root canals, the majority of the isolated bacteria are either strict anaerobes or microaerophilic organisms. Among thease, Black-pigmented Bacteroides species are the most important and have relation with clinical symptoms. The purpose of this study were to investigate on the 7 different types of bacteria which include Black-pigmented Bacteroides - Black--pigmented Bacteroides, Actinobacillus actinomycetemcomitans, Streptococcus, Capnocytophaga, Eiknella corrodens, Fusobacterium, Actinomyces - and the interrelationship between these 7 bacterical species, and to compare Black-pigmented Bacteroides with the clinical symptoms in infected root canals. The canal contents of 15 necrotized teeth with 8 clinical symptoms were sampled and cultured aerobically and anaerobically for growth in 7 selective agar plates for 7 bacterial species. Black-pigmented Bacteroides and Streptococcus subspecies were identified by biochemical tests. The results were as follows; 1. 70.51% of the bacteria isolated were anaerobes and 29.49% were aerobes. 2. B. loescheii, B. intermedius, B. denticola were isolated in 8 cases, Streptococcus was isolated in 8 cases, Fusobacterium was isolated in 6 cases, Actinomyces was isolated in 5 cases and Eiknella corrodens, Actinobacillus actinomycetemcomitans, Capnocytophaga were not isolated. 3. There were mutual inhibition of growth between Black-pigmented Bacteroides and Streptococcus. (P<0.01) But Actinomyces and Fusobacterium showed mutual aids for growth. (P<0.05) 4. Black-Pigmented Bacteroides was found to be related both to sinus tract formation and to apical sensitivity to palpation.(P < 0.05).

• Journal of Sericultural and Entomological Science
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• v.7
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• pp.53-63
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• 1967

In order to identify the bacteria living on the cocoons in Korea, the isolated bacterias' morphological. cultural and physiological characters has been determined through the detailed study. The second aim of this experiment was to protect against the bacteria which damage silk protein during storage. 1. The twelve strains of the bacteria were isolated and identified in the cocoons produced in Korea. The results of the identification are as the following. No 1, No 8; Bacillus subtilis variation No 2, ; Bacillus stearothermophilus No 3, ; Bacillus circulans No 5, No 6; Bacillus thuringiensis No 7, No 11; Bacillus brevis No 12, No l0; Bacillus cereus variation