• Journal of Microbiology and Biotechnology
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• 제6권4호
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• pp.255-259
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• 1996

$\beta$-Glucosidase was known to be involved in the mutagenic activation of $\beta$-glucosides. The level of $\beta$-glucosidase in the feces of adults was 2.7 times higher than that of infants. There was no difference in the percentage of $\beta$-glucosidase positive strains among Bifidobacterium isolates between adults and infants, corresponding to 90 and 92$%$, respectively. However, the strains from adults showed 1.9 times higher enzyme activity than those from infants when grown in Brain Heart Infusion medium. $\beta$-Glucosidase negative strains could not ferment $\beta$-glucosidase substrates, such as cellobiose, salicin, naringin, esculin and arbutin. Presence of $\beta$-glucosidase in Bifidobacterium did not alter the degree of growth in reconstituted skim milk. The $\beta$-glucosidase level was much lower in milk and vegetable medium, although cells grew above $10^8$cfu/ml, than in BHI medium. This study suggests that metabolic activation of the $\beta$-glucosides by Bifidobacterium $\beta$-glucosidase varies significantly depending on types of growth medium.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.453-458
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• 1994

Intestinal microbial flora comprise one third of the large intestinal contents in human. They play a significant effects through beneficial and harmful action on the human health. This is the first study which examined the composition of the microflora of the general population in Korea. Bacteroides, Bifidobacterium, Eubacterium, Peptostreptococcus, Lactobacillus, Streptococcus, Escherichia coli, Staphylococcus, Clostridium perfringens, total aerobic bacteria and total anaerrobic bacteria were counted using various selective and non-selective media. Among the bacteria studied the number of Bifidobacterium were greatest in breast-fed infants(30-90 days old), whereas Streptocuccus and Bifidobacterium in bottle-fed infants. In 20-40 age group Bacteroides were predominant followed by Bifidobacterium and Eubacterium. In early group(over 65 years old) Bacteroides were predominant followed by Eubacterium and bifidobacterium. The frequency and number of Cl. perfringens were highest in dlderly group. These results confirm that the microfloral pattern in large intestine change during the life cycle of humans.

• 한국미생물·생명공학회지
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• 제49권1호
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• pp.1-8
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• 2021

Human breast milk is a potential source of bacteria for the development of the intestinal microbiota of infants. Several species within the genera Lactobacillus and Bifidobacterium were demonstrated to shape the gut microbiota of infants. In this study, the bacterial diversity was investigated in the breast milk and feces of a mother-infant pair, and probiotic candidates were identified. Importantly, the novel L. gasseri EJL and B. breve JTL strains were isolated from breast milk and infant feces samples, respectively; their completed genome was resolved using de novo sequencing. In addition, the bacterial composition in the infant's feces at 1 week revealed the prevalence of Bifidobacterium and Streptococcus; a higher diversity was observed after 3 weeks. In particular, the abundance of Akkermansia was sharply increased at 7 weeks, further increasing thereafter, up to 15 weeks. Our results suggest that human breast milk and infant's feces are a source of probiotic candidates.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.422-425
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• 2001

For isolating and identifying Bifidobacterium spp. originating from Korea, feces were sampled from healthy Korean infants nursery school and postpartum care center. Through the use of gram staining and microscopic examination for cell morphology, 87 bacterial strains presumed to be the Bifidobacterium strains were isolated from 59 Koreans. To identify the Bifidobacterium strains at the genus level, these bacteria were then analyzed using the TLC method. As a result, 29 of the isolated strains were confirmed as members of the genus Bifidobacterium. 29 Bifidobacterium strains were tested acid, bile salts and oxygen tolerance and investigated antioxidative effect specially. And determined the superiority of 5 strains out of 29 Bifidobacterium strains. Finally, the selected bifidobacterium was identified with using designed 16S-ITS rDNA primer.

• 미생물학회지
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• 제55권3호
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• pp.268-273
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• 2019

장 내에 존재하는 microbiome은 생활환경, 나이와 섭취하는 음식물에 따라 변하게 된다. 본논문에서는 모유를 섭취한 영아와 분유를 섭취한 영아들에 대한 장내미생물 군집의 변화를 비교하였다. 미생물의 군집변화를 차세대 염기서열 분석기법을 이용하여 분석하였으며 총 80개의 영아 분변을 통해 미생물 군집변화를 확인하였다. 모유그룹(BIG)과 분유그룹(FIG-A, FIG-B, FIG-C)간의 장내세균의 군집을 비교한 결과 BIG에서는 Actinobacteria 문이 전체 군집의 $74.22{\pm}3.48%$로 우점을 차지하였다. 분유그룹의 Actinobacteria 문을 비교하였을 때 FIG-A는 $73.46{\pm}4.12%$였지만 FIG-B와 FIG-C는 $66.52{\pm}5.80%$와 $68.88{\pm}4.33%$로 BIG와 FIG-A에 비해 낮은 비율을 보였다. 속(genus) 수준에서 살펴보면 Bifidobacterium이 전체 미생물군집에서 가장 높은 비율로 분포하고 있었으며 BIG가 $73.09{\pm}2.31%$로 가장 높았고 FIG-A, FIG-B 및 FIG-C는 각각 $72.25{\pm}4.93%$, $63.81{\pm}6.05%$ 및 $67.42{\pm}5.36%$를 차지하였다. Bifidobacterium 종의 경우 모든 그룹에서 Bifidobacterium longum이 우점을 차지하고 있었으며 BIG와 FIG-A가 전체 군집의 $68.77{\pm}6.07%$와 $66.85{\pm}5.80%$를 차지하였다. 이에 반해 FIG-B와 FIG-C는 각각 $58.94{\pm}6.20%$와 $61.86{\pm}5.31%$로 BIG와 FIG-A보다 낮은 비율로 분포하는 것을 분석하였다. FIG-A가 섭취한 분유는 Bifidobacterium의 선택적 증식이 우수하다고 알려진 갈락토올리고당, 갈락토실락토스, 시너지올리고당, 비피도올리고 및 장내균총개선소재를 혼합한 5-Bifidus factor 복합물이 포함되어 있다. 이와 같은 5-Bifidus factor라는 유산균에 대한 증식능이 우수한 프리바이오틱스를 혼합하였기 때문에 모유를 섭취한 영아의 장내에 존재하는 Bifidobacterium 속의 군집과 유사하게 나타난 것으로 판단된다.

• Nutrition Research and Practice
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• 제9권3호
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• pp.242-248
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• 2015

BACKGROUND/OBJECTIVES: Feeding in infancy is the most significant determinant of the intestinal microbiota in early life. The aim of this study was to determine the gut microbiota of Korean infants and compare the microbiota obtained between breast-fed and formula-fed Korean infants. SUBJECTS/METHODS: We analyzed the microbial communities in fecal samples collected from twenty 4-week old Korean (ten samples in each breast-fed or formula-fed) infants using pyrosequencing. RESULTS: The fecal microbiota of the 4-week-old Korean infants consisted of the three phyla Actinobacteria, Firmicutes, and Proteobacteria. In addition, five species, including Bifidocbacterium longum, Streptococcus salivarius, Strepotococcus lactarius, Streptococcus pseudopneumoniae, and Lactobacillus gasseri were common commensal intestinal microbiota in all infants. The predominant intestinal microbiota in the breast-fed infants (BFI) included the phylum Actinobacteria (average 70.55%), family Bifidobacteriacea (70.12%), genus Bifidobacterium (70.03%) and species Bifidobacterium longum (69.96%). In the microbiota from the formula-fed infants (FFI), the proportion of the phylum Actinobacteria (40.68%) was less, whereas the proportions of Firmicutes (45.38%) and Proteobacteria (13.85%) as well as the diversity of each taxonomic level were greater, compared to those of the BFI. The probiotic species found in the 4-week-old Korean infants were Bifidobacterium longum, Streptococcus salivarius, and Lactobacillus gasseri. These probiotic species accounted for 93.81% of the microbiota from the BFI, while only 63.80% of the microbiota from the FFI. In particular, B. longum was more abundant in BFI (69.96%) than in FFI (34.17%). CONCLUSIONS: Breast milk supports the growth of B. longum and inhibits others. To the best of our knowledge, this study was the first attempt to analyze the gut microbiota of healthy Korean infants according to the feeding type using pyrosequencing. Our data can be used as a basis for further studies to investigate the development of intestinal microbiota with aging and disease status.

• 한국식품영양과학회지
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• 제33권8호
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• pp.1348-1352
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• 2004

인체의 장관에서 유래한 200여 Bifidobacteria 균주를 대상으로 CLA 생산능을 조사한 결과, 공시균주 1종과 국내의 유아로부터 분리한 12개 균주가 기질로 첨가한 LA를 CLA로 전환하였으며, 각 CLA 생산 균주들에 의한 CLA 이성체는 90% 이상이 cis-9, trans-11 CLA이었다. CLA 생산능과 전환율이 가장 높은 Bifidobacterium sp. KHU 141 균주를 사용하여 발효유를 제조하였을 때, 발효유의 CLA 함량은 대조구보다 39.6 mg/100 g 증가하여 CLA의 생리활성 효과를 기대할 수 있는 발효유의 생산에 사용할 수 있는 균주로 나타났다. Bifidobacterium sp. KHU 141에 의한 fermenter에서의 발효유 제조 시 lauric acid, myristric acid, palmitic acid, oleic acid 및 linolenic acid 함량은 큰 변화를 보이지 않았으나, LA 함량은 감소하고 CLA 함량은 증가하여 배양 24시간 및 48시간 후에 각각 소비된 LA의 86.0%및 84.8%가 CLA로 전환되었다. Bifidobacterium sp. KHU 141에 의한 CLA 생산은 배양 24시간과 48시간 사이에 큰 차이가 없었으며 fermenter에서의 CLA 생산능도 bottle이나 시험관을 이용하여 발효한 경우와 같이 안정적으로 유지되었다.

• Journal of Dairy Science and Biotechnology
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• 제24권1호
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• pp.19-28
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• 2006

유아 분변으로부터 분리한 52 균주는 그람 양성균인 Listeria monocytogenes KCCM 40307$^T$에 대하여 항균활성이 있었고 그 중에서도 선별 균주 A24의 항균활성이 45% 이상으로 가장 높았다. Bifidobacterium longum A24의 생육 및 항균 물질 생산을 검토하였을 때 균체의 생육은 28시간 배양 시 최고에 도달하였고 항균 활성은 36시 간 배양 시 최고를 나타내었다. 선별균주 A24는 16S rRNA-based molecular typing 결과Bifidobacterium 속 균주임을 확인할 수 있었고 형태학적 ${\cdot}$ 생화학적인 방법으로 검토하여 보았을 때 Bifidobacterium longum으로 판단되었으며, 16s rDNA sequencing 결과 최종적으로 Bifidobacterium longum로 동정 되었으며 이것을 Bifidobacterium longum A24로 명명하였다. Bifidobacterium longum A24의 항균 활성 물질은 균체의 생육이 가장 좋은 28시간 배양에서가 아니라 그보다 늦은 36시간 배양에서 최고를 나타내었고 그 이후로는 활성이 감소하는 경향을 보였다. 이것은 Bifidobacterium longum A24이 생성하는 항균 활성 물질이 bacteriocin과 같은 2차 대사 산물임을 암시하는 결과로 해석된다.

• KSBB Journal
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• 제25권4호
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• pp.319-329
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• 2010

Bifidobacteria comprises up to 25% of the cultivable fecal bacteria in adults and 80% in infants. Many in vivo and clinical research results supporting its efficacy in the prevention and improvement of gastrointestinal health have been accumulated. As a consequence, expert committee WHO/FAO expert committee recommended Bifidobacterium as representative probiotics together with Lactobacillus acidophilus. In this review, research trends in bifidobacteria concerning the classification and identification of the genus Bifidobacterium, modulation of intestinal microflora, improvement of constipation, prevention of diarrhea, alleviation of atopy and allergy, barrier function through antimicrobial activity andimmune enhancement of the host will be introduced. Several gene expression systems based on bifidobacterial plasmids have been developed and successfully used to express several heterologous genes including anticancer proteins in Bifidogacterium. In animal test, bifidobacteria was proven to be a promising candidate for safe gene delivery system which can specifically colonize in the solid tumor.

• Journal of Dairy Science and Biotechnology
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• 제37권1호
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• pp.40-48
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• 2019

Bifidobacteria are a prototype probiotic, which normally inhabit the intestinal tract of humans. In the present study, four species of Bifidobacterium isolated from the feces of infants were characterized. The tolerance for acid or bile salt, autoaggregation, and antibiotic resistance of the bacteria were examined. The four species were resistant to low pH, bile salts, and up to 3% bile acid. Autoaggregation rates were as high as 90%. The bacteria were consistently resistant to gentamicin, kanamycin, streptomycin, ciprofloxacin, and nalidixic acid. Due to their tolerance to environmental factors like acid and bile salts, B. longum MG723, B. breve MG729, B. bifidum MG731, and B. animalis subsp. lactis MG741 are potentially valuable as probiotics and may be useful for industrial application.