• Journal of Microbiology and Biotechnology
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• v.7 no.3
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• pp.174-179
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• 1997

In order to investigate effect of glucooligosaccharide (GOS) prepared by extrusion process as a bifidogenic factor, cultivation of Bifidobacterium sp., Bacteroides fragilis and Clostridium perfringens was done and analyzed. B. fragilis and C. perfringens were able to utilize only 16% and 11% of the oligosaccharides in GOS, respectively, whilst Bifidobacterium sp. FBD-22 could utilize 38%. Especially, many kinds of oligo saccharides in GOS were able to be utilized selectively only by Bifidobacterium sp.. In case that GOS, as a carbon source, was used in the co-cultivation by Bifidobacterium sp., B. fragilis and C. perfringens, growth of Bifidobacterium sp. was not influenced by the existence of B. fragilis and C. perfringens. Bifidobacterium sp. showed advantage on carbon source competition for GOS with B. fragilis. Acetic acid, antimicrobial agent in the intestine, was produced two times more from GOS than glucose in co-cultures of three strains. Therefore, it is suggested that GOS can be a potent bifidogenic factor which proliferates the population of Bifidobacterium sp. and may finally improve the intestinal environments of human.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.526-531
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• 1994

In order to develop a new improved selective medium for the Bifidobacterium sp. from the human fecal samples, one hundred eight Bifidobacterium strains were isolated and identified. Sensitivity test for the antibiotics and antimetabolites and test for the specific substrate were performed to obtain basic data for the development of the Bifidobacterium selective medium. TOS(transgalactosylated oligosaccharide) was shown to be preferentially used by Bifidobacterium sp.. Sodium propionate promoted the growth of Bifidobacterium while inhibiting other intestinal bacteria. Upon these results, TP medium was designed and shown to be very effective for the selection of Bifidobacterium and better than Mitsuoka BS medium.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.8-13
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• 2002

The isoflavone glycosides are hydrolyzed by ${\beta}$-glucosidase from gut microbes to the bioactive aglycones. However, the specific bacteria from the human intestinal tract that are involved in the metabolism of these compounds are not known. This study was undertaken to develop a fermented soymilk which converts isoflavones to the more bioactive aglycones form using a Bifidobacterium strain. The ${\beta}$-glucosidase activity of 15 Bifidobacterium strains were measured during cell growth. Among them, Bifidobacterium sp. Int-57 was selected for this study, because it has the highest ${\beta}$-glucosidase activity. Growth, acid development, ${\beta}$-glucosidase activity, and the hydrolysis of daidzin and genistin were investigated in four soymilks inoculated with Bifidobacterium sp. Int-57. After 12 h of fermentation, the counts of viable Bifidobacterium sp. Int-57 in all the soymilks reached a level of more than $10^8$ cfu/ml, which was then maintained. The pH of soymilks started to decrease rapidly after 6 h of fermentation and leveled off after 18 h. The titratable acidity of BL# 1 soymilk, BL#2 soymilk, and JP#l soymilk increased from 0.18 to 1.21, 1.15, and $1.08\%$ over the fermentation period, respectively. After 24 h of fermentation, the $\beta$-glucosidase activity in BL#1 soymilk, BL#2 soymilk, JP#l soymilk, and JP#2 soymilk increased to 59.528, 40.643, 70.844, and 56.962 mU/ml, respectively. The isoflavone glycosides, daidzin and genistin, in soymilks were hydrolyzed completely in the relatively short fermentation time of 18 h. These results show that Bifidobacterium sp. Int-57 can be used as a potential starter culture for developing fermented soymilk which has completely hydrolyzed isoflavone glycosides.

• 한국약용작물학회:학술대회논문집
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• 2009.05a
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• pp.397-398
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• 2009

• Journal of Microbiology and Biotechnology
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• v.11 no.1
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• pp.1-6
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• 2001

Ten strains of plasmid-harboring Bifidobacterium sp. were isolated from the feces of adults and children, and named as Bifidobacterium sp. GE1-GE8, ST, and SH5. These plasmids were categorized into three homologous groups (pKJ50-homologous, pKJ36-homologous, and non-homologous groups) according to Southern hybridization patterns using the formerly characterized bifidobacterial plasmids, pKJ50 and pKJ36, as probes. nine strains harboring the plasmids were shown to accumulate single-stranded DNA as a replication intermediate, based on the S1 nuclease treatment and Southern hybridization. These results suggest that the strains replicate by a rolling circle mechanism. Minimal inhibitory concentrations (MIC) of the isolated bifidobacteria against several antibiotics were determined. Two strains, GE2 and GE3, showed relatively high MiC values against tetracycline ($793.6{\mu}g/ml$) and erythromycin ($153.6{\mu}g/ml$), respectively. The tetracycline resistance of GE2 disappeared when the resident plasmid of GE2 was cured by ethidium bromide. These results show that pKJ36-homologous and pKJ50-homologous plasmids are prevalent among various Bifidobacterium strains and some Bifidobacterium plasmids appear to code for antibiotic resistance.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.89-93
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• 1993

In order to study the effect of the intestinal bacteria on the physiology of the human large intestinal tract, we isolated the intestinal bacteria of Koreans and tested the enzymatic patterns. Isolated Bifidobacterium sp. Int-57 showed the higher activity of ${\beta}-xylosidase$ than other intestinal microorganisms. The effect of the carbon sources, nitrogen sources, inorganic salts, initial pH and initial temperature on the production of ${\beta}-xylosidase$ of Bifidobacterium sp. Int-57 was investigated. The most suitable carbon source, nitrogen source and inorganic salt for the production of ${\beta}-xylosidase$ were 1.1% xylose, 0.4% yeast extract and 0.0003% $CoCl_2$ respectively at initial pH 7.0 and temperature $40^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1348-1352
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• 2004

More than 200 Bifidobacterium sp. originated from human intestine were investigated for their ability to produce conjugated linoleic acid (CLA). Of the Bifidobacteria tested, 1 of culture type strain and 12 isolated strains from Korean infants showed CLA producing ability. cis-9, trans-11 octadecadienoic acid presented more than 90% of the total CLA isomers produced by the Bifidobacteria. CLA content in fermented milk by Bifidobacterium sp. KHU 141 increased by 39.6 mg/l00 g, which showed the potential use for producing fermented milk containing high content of CLA. In fermented milk, little changes showed in lauric acid, myristric acid, palmitic acid, oleic acid, and linolenic acid contents, whereas the content of linoleic acid (LA) decreased and the content of CLA increased. Bifidobacterium sp. KHU 141 converted 86.0% and 84.8% of LA consumed to CLA for 24 hr and 48 hr fermentation, respectively. Prolonging incubation from 24 to 48 hours did not appear to enhance CLA formation and CLA producing ability was stable whether bottle, test tube, or fermenter was used for making fermented milk by Bifidobacterium sp. KHU 141.

• Journal of the Korean Society of Food Culture
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• v.17 no.2
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• pp.165-170
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• 2002

In order to economically utilize dough with B. longum, B. infantis and B. brevis as a bread improver, aerotolerance, ${\alpha}-galactosidase$ activity, organic acids, farinograph and extensograph of dough were investigated. In aerotolerance of Bifidobacterium sp., B. longum was highest among tested starters, followed by B. infantis. The ${\alpha}-galactosidase$ activity was highest in the B. longum among tested starters. In organic acids, the contents of lactic acid and acetic acid were the highest in the among tested starters, followed by B. infantis. In farinograms of dough, water absorption and peak time were highest in the B. brevis among tested dough. Extensogram showed that the area increased remarkably in B. longum and B. infantis at 135min of fermentation. Extensibility and resistance to extension of dough were highest in the B. infantis among the dough, followed B. longum.

• Journal of Nutrition and Health
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• v.28 no.11
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• pp.1065-1072
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• 1995

Mugwort was successively fractionated with n-hexane, chloroform, ethyl acetate, n-butanol and water and the fractions were evaluated by their growth-promoting activites for Bifidobacterium sp. in vitro experiments. The growths of Bifidobacterium adolescentis, B. bifidum, B. infantis and B.longum were enhanced with the addition of the water fraction, while the fractions of chloroform and ethylacetate inhibited Clostridium perfringens. When the wate fraction was added to media at a concentration of 0.01-0.5%(w/v), the growhts of Bifidobacterium sp. were increased according to the concentration of water fraction used. The water fraction stimulated also the growth of lactobacillus acidophillus, whereas those of E. coli and Enterococcus faecalis were not affected. The growth-promoting activity of water fraction was stable at the range of pH 2 to pH 10 and kept in thermal treatment at 10$0^{\circ}C$ for 30 minutes.

• Journal of Microbiology and Biotechnology
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• v.15 no.4
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• pp.740-744
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• 2005

Bifidobacterium has been previously shown to potentiate immune function, which was mediated through the stimulation of cytokine production by macrophage. This study was performed to further characterize the effective component of Bifidobacterium by measuring the level of interleukin (IL)-6 cytokine using the RAW 264.7 murine cell line as a macrophage model. RAW 264.7 cells were cultured for 24 h in the presence of whole cells (WCs), cell walls (CWs), and cell-free extracts (CFEs) from various strains of Bifidobacterium and other lactic acid bacteria at various concentrations. The most effective component was different depending on the strains and the concentrations used. When tested with each cell fraction from Bifidobacterium sp. BGN4, heat treatment of the cell fractions lowered the production of IL-6. Synergistic effect was obtained, especially when CWs and CFEs were combined. Sonicated WCs stimulated IL-6 production more than intact WCs. The in vitro approaches employed here should be useful in further characterization of the effects of Bifidobacterium on gastrointestinal and systemic immunity.