• Food Science and Biotechnology
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• 제15권5호
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• pp.677-682
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• 2006

Strain HY701 was isolated from human feces for probiotic use by selecting highly resistant isolates to artificial gastric acid and bile acid. Strain HY701 was identified as Lactobacillus reuteri using 16S rDNA sequencing, and tentatively named L. reuteri HY701. The resistance of L. reuteri HY701 to artificial gastric acid (PH 2.5) was high with a survival rate of over 90%. L. reuteri HY701 also showed high tolerance to artificial bile acid after incubation in artificial gastric acid. Using the API ZYM test kit, the carcinogenic enzymes (${\beta}$-glucuronidase and (${\beta}$-glucosidase were not detected with L. reuteri HY70l, while the beneficial enzyme (${\beta}$-galactosidase was weakly detected. L. reuteri HY701 was sensitive to $100\;{\mu}g/mL$ nisin, $20\;{\mu}g/mL$ roxithromycin, $15\;{\mu}g/mL$ erythromycin, but resistant to $20\;{\mu}g/mL$ streptomycin, $10\;{\mu}g/mL$ tetracycline, $20\;{\mu}g/mL$ ciprofloxacin, $20\;{\mu}g/mL$ nystatin, $20\;{\mu}g/mL$ gentamycin, $10\;{\mu}g/mL$ doxycycline, $10\;{\mu}g/mL$ chloramphenicol, and $20\;{\mu}g/mL$ ampicillin. L. reuteri HY701 was shown to possess bactericidal activity as it inhibited the growth of Listeria monocytogenes ATCC 19111 and Escherichia coli JM109 completely within 24 hr of incubation. These results indicate that L. reuteri HY701 could be used as a probiotic strain.

• 한국가금학회지
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• 제27권1호
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• pp.37-41
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• 2000

This study was carried out to examine the effects of Lactobacillus spp. on performance and cecal microflora in broiler chicks. Eight diets consisting of basal diet(C), C+Lactobacillus crispatus BC7 (T2), C+Lactobacillus reuteri BC9 (T3), C+L.reuteri BC5+L.crispatus BC9 (T4), C+L. reuteri BC5 (T1)+L.reuteri BC9 (T5), C+L.crispatus BC7+L.reuteri BC9 (T6) and C+L.reuteri BC5+L.crispatus BC7+L.reuteri BC9 (T7), were fed to Ross male broiler chicks for 5 weeks. The level of supplemented Lactobacillus spp. was 107 cfu/g diet. Body weight and feed intake were measured every week, and cecal microfla was counted at 1 and 5 weeks for Lactobacillus and yeast. Body weight increased signigicantly in supplemental Lactobacillus treatments from 2 weeks of age (p<0.05). Chicks in T2, T5 and T5 of treatments were heavier than those of other treatments at 5 weeks of age(p<0.05). Viability was not different significantly. Feed intake and feed conversion also were not different, although feed conversion improved slightly in supplemental Lactobacillus treatments. Lactobacillus spp. of cecal content was increased in supplemental Lactobacillus treatments at 1 week, but no significance was found. The number of yeast in cecum was not different from that of supplemental Lactobacillus. In conclusion, Lactobacillus, L.crispatus BC7 and L.reuteri BC9 from broiler cecum could contribute to the increase in body weight with supplemented mono-or mixing of di-lactobacilli. The results indicate that Lactobacillus feeding can benefit to intestinal lactobacillus at early growing broiler.

• Food Science and Biotechnology
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• 제17권2호
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• pp.438-441
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• 2008

A novel lactobacilli replicon from plasmids of Lactobacillus reuteri KCTC 3678 was isolated. Eight L. reuteri strains from Korean Collection for Type Cultures (KCTC) and Korea Food Research Institute (KFRI) were screened for cryptic plasmids and most strains harbored 1 or 2 plasm ids. Particularly, L. reuteri KCTC 3678 contained 6 plasm ids which all were used for screening of lactobacilli replicon. EcoRI digests of the plasmid DNA prep from L. reuteri KCTC 3678 were ligated with pUC19 and the recombinant DNAs were serially named from pLR1 to pLR7. A cat (chloramphenicol acetyltransferase; $Cm^r$) gene originated from pC194 was introduced into pLR1-7, resulting in pLR1cat-pLR7cat, respectively. The recombinant plasmids were introduced into L. reuteri KCTC 3679, and only transformants harboring pLR5cat were obtained, indicating that the insert in pLR5 functioned as a lactobacilli replicon.

• 대한수의학회지
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• 제48권2호
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• pp.167-174
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• 2008

Lactic acid bacteria have been reported their beneficial roles on host including reduction of infectious diarrhea problems. In this study, preventive effect of Lactobacillus (L.) reuteri HY25101 and L. johnsonii HY25103 on porcine epidemic diarrhea virus (PEDV) was investigated in suckling piglets. Two groups of one day old PEDV naïve piglets were orally administered L. reuteri HY25101 and L. johnsonii HY25103 for three days respectively before challenge with lethal dose of PEDV. In second experiment, passive immunized one day old piglets using colostrums containing PEDV specific IgA were used. The survival rates of the L. reuteri HY25101 administered group were significantly higher than that of L. johnsonii HY25103 administered group and viral shedding was rapidly diminished in L. reuteri HY25101 administered group. Interestingly piglets born from the sow immunized with attenuated PEDV vaccine were not completely protected from PEDV challenge, however coadministeration of L. reuteri HY25101 and colostrums containing PEDV specific IgA were more effectively prevent PEDV infection. These results suggested that dietary treatment using L. reuteri HY25101 could reduce diarrheal problem and mortality rate caused by PEDV in suckling pigs. In addition, L. reuteri HY25101 could be used as one of effective compensation treatment with attenuated live vaccine for PED.

• Clinical and Experimental Pediatrics
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• 제48권9호
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• pp.986-990
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• 2005

목 적 : Lactobacilli의 일부 균주는 급성 설사의 회복을 도와 준다. Lactobacillus reuteri는 인간에서 비롯된 균주로 위장관 내에 자연적으로 집락형성을 한다. 특히 유아설사를 일으키는 로타바이러스를 억제하여 영유아 설사를 완화시켜주고 장내 다른 유익한 유산균 수를 증가시켜준다는 보고가 있다. 본 연구에서는 경구로 L. reuteri를 투여하였을 때 급성 설사에서 치료적 효과가 있는지 여부를 확인하고자 하였다. 방 법 : 급성 설사로 입원한 6개월에서 36개월 사이의 영유아 50명(40% 로타바이러스)을 대상으로 하였다. 환아들을 각 25명씩 무작위로 $10^8$ colony-forming unit(CFU)를 투여하는 L. reuteri군과 위약을 투여하는 위약군으로 나누어 하루에 2회 L. reuteri나 위약을 입원 기간 동안 혹은 최대한 5일간 투여하였다. 임상적인 평가로 입원 후 수양성 설사 기간, 입원 기간, 수양성 설사 일수 및 횟수, 구토 일수 등을 조사하였다. 결 과 : 설사 후 수양성 설사의 평균 기간은 L. reuteri군에서 2.3일이었으며 위약군에서 2.9일로 L. reuteri군에서 짧았으나 통계적 차이가 없었다(P=0.072). 치료 2병일째 수양성 설사는 L. reuteri군에서 64%이었으며 위약군에서 84%로 통계학적 차이가 있었다(P=0.006). 치료 2병일째 평균 수양성 설사횟수는 L. reuteri군에서 1.9회이었으며 위약군에서 3.4회로 통계학적 차이가 있었다(P=0.046). 치료 2병일째 구토는 L. reuteri군에서 16%이었으며 위약군에서 40%로 통계학적 차이가 있었다(P=0.031). 결 론 : 이상의 결과는 Lactobacillus reuteri가 영유아 설사에 치료효과가 있다는 것을 시사한다.

• Journal of Microbiology and Biotechnology
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• 제25권6호
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• pp.893-902
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• 2015

Various Lactobacillus reuteri strains were screened for the ability to convert glycerol to 1,3-propanediol (1,3-PDO) in a glycerol-glucose co-fermentation. Only L. reuteri DSM 20016, a well-known probiotic, was able to efficiently carry out this bioconversion. Several process strategies were employed to improve this process. Co²⁺ addition to the fermentation medium, led to a high product titer (46 g/l) of 1,3-PDO and to improved biomass synthesis. L. reuteri DSM 20016 produced also ca. 3 µg/g of cell dry weight of vitamin B₁₂, conferring an economic value to the biomass produced in the process. Incidentally, we found that L. reuteri displays the highest resistance to Co²⁺ ions ever reported for a microorganism. Two waste materials (crude glycerol from biodiesel industry and spruce hydrolysate from paper industry) alone or in combination were used as feedstocks for the production of 1,3-PDO by L. reuteri DSM 20016. Crude glycerol was efficiently converted into 1,3-PDO although with a lower titer than pure glycerol (33.3 vs. 40.7 g/l). Compared with the fermentation carried out with pure substrates, the 1,3-PDO produced was significantly lower (40.7 vs. 24.2 g/l) using cellulosic hydrolysate and crude glycerol, but strong increases of the maximal biomass produced (2.9 vs 4.3 g/l CDW) and of the glucose consumption rate were found. The results of this study lay the foundation for further investigations to exploit the biotechnological potential of L. reuteri DSM 20016 to produce 1,3-PDO and vitamin B₁₂ using industry byproducts.

• 한국축산식품학회지
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• 제43권1호
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• pp.157-169
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• 2023

Effects of culture supernatants of Lactobacillus reuteri MG5346 (CS-MG5346) on receptor activator of nuclear factor-kappa B ligand (RANKL)-induced osteoclastogenesis were examined. CS-MG5346 treatment up to 400 ㎍/mL significantly reduced tartrate-resistant acid-phosphatase (TRAP) activity, the phenotype biomarker of osteoclast, without affecting cell viability. CS-MG5346 inhibited the expression of osteoclast specific transcriptional factors (c-fos and nuclear factor-activated T cells c1) and their target genes (TRAP, cathepsin, and matrix metallo-proteinase-9) in a dose-dependent manner (p<0.05). The administration of L. reuteri MG5346 (2×10⁸ CFU/day) for 8 wks significantly improved furcation involvement, but no difference was observed in alveolar bone loss in ligature-induced experimental periodontitis rats. The elevated RANKL/osteoprotegerin ratio, the biomarker of periodontitis, was significantly lowered in the gingival tissue by administration of L. reuteri MG5346 (p<0.05). L. reuteri MG5346 showed excellent stability in simulated stomach and intestinal fluids and did not have antibiotic resistance. Based on the results, L. reuteri MG5346 has the potential to be a promising probiotic strain for oral health.

• Journal of Microbiology and Biotechnology
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• 제12권5호
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• pp.716-721
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• 2002

The ldhL gene encoding the $_L$-(+) lactate dehydrogenase was cloned from Lactobacillus reuteri ATCC 55739 chromosomal DNA and characterized. An internal 750-bp fiagment of ldhL gene was amplified by PCR using primers based on the conserved region of lactobacilli ldhL genes. A genomic library off. reuteri ATCC 55739 was constructed using pBR322, and colony hybridization experiments were performed using the 750-bp fragment as aprobe. One clone harboring a 4.0-kb PstI fragment was identified, and nucleotide sequencing confirmed it as an open reading frame of 972 bp in size in the middle. In addition to IdhL gene, an ORF homologous to Streptococcus pneumoniae TIGR4 hydrolase gene and 3' part of phosphomevalonate kinase gene (mvaK2) were also found on the 4 kb fragment. $_L$-LDH of L. reuteri ATCC 55739 showed the highest degree of homology with the $_L$-LDH of Pediococcus acidilactici (62.4%), fullowed by the $_L$-LDH of Lactobacillus pentosus (58.7%). The size of IdhL transcript determined by Northern blot was 1 kb, indicating the monocistronic nature of IdhL.

• 한국식품과학회지
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• 제37권2호
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• pp.318-320
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• 2005

Lactobacillus reuteri는 사람과 동물의 장관 내에 존재하는 유산균의 일종으로서 혐기적 조건에서 glycerol을 대사하여 항균 물질인 루테린을 생산한다. 본 연구의 목적은 고정화된 L. reuteri를 이용하여 회분식 또는 연속식 생산 공정을 이용하여 루테린 생산의 반응 조건을 조사하는데 있었다. Agarose를 사용하여 고정화된 L. reuteri는 250mM glycerol과 반응시켜 루테린을 생산하였다. Agarose 농도를 0.5%로 조정한 회분식 생산 공정에서는 약 36시간 동안 루테린 생산이 지속되었고 시간 경과에 따라 루테린의 생산이 점차 감소하였다. 연속식 공정에서는 고정화 균이 현탁세포에 비하여 루테린 생산 시간이 약 2배 정도 연장되었으며 총 루테린의 생산 또한 502mM로 현탁 세포에 비하여 약 1.5배 증가하였다. 본 연구의 결과는 고정화 세포를 이용한 루테린 생산의 증가 가능성을 제시하였다.

• 한국초지조사료학회지
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• 제34권4호
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• pp.269-276
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• 2014

본 연구에서는 hetero 발효유산균 첨가가 이탈리안 라이그라스 및 총체보리 사일리지의 사료가치 및 발효품질에 미치는 영향을 조사하였다. 사일리지 접종균주를 선발하기 위해 유산균 6종(L. plantarum IMAU 70164, L. acidophilus KACC 12419, L. casei KACC 12413, L. reuteri KCTC 3594, L. buchneri KACC 12416 and L. diolivorans KACC 12385)을 이용하였으며, 젖산 함량이 높은 L. casei KACC 12416와 프로피온산 함량이 높은 L. reuteri KCTC 3594을 최종 선택하여 사일리지를 제조하였다. 처리구는 대조구, L. casei 첨가구, L. reuteri 첨가구 및 L. casei, L. reuteri 혼합첨가구로 하여 30일, 45일 및 60일간 저장하였다. pH는 IRG 사일리지의 경우 유산균 첨가구가 대조구에 비해 낮았으며(p<0.05), 수분함량, 젖산 및 초산함량 또한 유산균을 첨가한 처리구에서 낮은 것으로 나타났다(p<0.05). 수용성 탄수화물의 함량은 L. casei KACC 12416와 L. reuteri KCTC 3594를 혼합배양한 처리구에서 가장 낮았다(p<0.05). 프로피온산은 유산균을 접종한 총체보리에서 전 기간동안 높게 나타났으며, 반면에 사일리지 품질을 저해시키는 butyrate는 발효 60일의 대조구에서 측정되었다. 사일리지의 미생물 측정결과 IRG 사일리지 배양 60일에 유산균 첨가구에서 곰팡이가 억제되었으며, WCB 사일리지는 유산균을 첨가한 처리구에서 곰팡이가 검출되지 않았다. 이상의 연구 결과들로 볼 때, 단일 균주를 접종한 사일리지에 비해 co-culture (L. casei + L. reuteri)로 접종했을 때 사일리지 저장품질 개선에 보다 효과적이었으며, 혼합배양한 처리구가 청보리 사일리지내 높은 프로피온산을 생성하며 이는 사일리지의 품질개선에 도움을 주는 것으로 조사되었다.