• Asian-Australasian Journal of Animal Sciences
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• 제21권4호
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• pp.603-615
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• 2008

Dietary fiber is an inevitable component in pig diets. In non-ruminants, it may influence many physiological processes in the gastrointestinal tract (GIT) such as transit time as well as nutrient digestion and absorption. Moreover, dietary fiber is also the main substrate of intestinal bacteria. The bacterial community structure is largely susceptible to changes in the fiber content of a pig's diet. Indeed, bacterial composition in the lower GIT will adapt to the supply of high levels of dietary fiber by increased growth of bacteria with cellulolytic, pectinolytic and hemicellulolytic activities such as Ruminococcus spp., Bacteroides spp. and Clostridium spp. Furthermore, there is growing evidence for growth promotion of beneficial bacteria, such as lactobacilli and bifidobacteria, by certain types of dietary fiber in the small intestine of pigs. Studies in rats have shown that both phosphorus (P) and calcium (Ca) play an important role in the fermentative activity and growth of the intestinal microbiota. This can be attributed to the significance of P for the bacterial cell metabolism and to the buffering functions of Ca-phosphate in intestinal digesta. Moreover, under P deficient conditions, ruminal NDF degradation as well as VFA and bacterial ATP production are reduced. Similar studies in pigs are scarce but there is some evidence that dietary fiber may influence the ileal and fecal P digestibility as well as P disappearance in the large intestine, probably due to microbial P requirement for fermentation. On the other hand, fermentation of dietary fiber may improve the availability of minerals such as P and Ca which can be subsequently absorbed and/or utilized by the microbiota of the pig's large intestine.

• Preventive Nutrition and Food Science
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• 제12권1호
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• pp.58-63
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• 2007

Bifidobacteria are probiotic organisms that provide both flavor and health benefits when incorporated as live cultures into commercial dairy products. Because bifidobacteria are very sensitive to environmental conditions (acids, temperature, oxygen, bile salts, the presence of other cultures, etc.), their viability in human gastrointestinal tract is limited. The microencapsulation of bifidobacteria is a process to protect them against harsh environmental conditions, thereby increasing their viability while passing through human gastrointestinal tract. To confirm the survival rate of microencapsulated Bifidobacterium breve CBG-C2 in milk, their survival rate was compared with several kinds of free bifidobacteria and lactic acid bacteria in commercial yogurt products under simulated gastric and small intestinal conditions. Double-microencapsulation of the bacteria was employed to increase the survival rate during digestion. The outer layer was covered with starch and gelatin to endure gastric conditions, and the inner layer was composed of a hard oil for the upper small intestinal regions. Almost all microencapsulted bifidobacteria in the milk survived longer than the free bifidobacteria and lactic acid bacteria in the commericial yogurt products under the simulated gastric conditions. Numbers of surviving free bifidobacteria and lactic acid bacteria in the commercial products were significantly reduced, however, the viability of the microencapsulated bificobacteria in the milk remained quite stable under gastric and small intestine conditions over 3$\sim$6 hrs. Thus double-microencapsualtion of bifidobacteria in milk is a promising method for improving the survival of bifidobacteria during the digestive process.

• 한국식품영양학회지
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• 제28권6호
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• pp.956-964
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• 2015

Loperamide를 통해 변비가 유발된 실험동물에 유산균 투여가 미치는 영향을 알아보기 위하여 14일 동안 저농도($10^7CFU/mL$ per kg of body weight)의 유산균과 고농도($10^9CFU/mL$ per kg of body weight)의 유산균을 투여한 후, 변비개선 효과를 측정하였다. 그 결과, 변비 유발 후 유산균을 투여한 실험군들의 경우, 대조군(CON)에 비하여 변의 개수, 변 중량 및 수분 함량이 유의적으로 증가하였다. 또한 소화관 이동률을 조사한 결과, 대조군(CON)에 비하여 변비 유발 후 유산균을 투여한 군에서 정상대조군(NOR)인 군과 유사한 이동성을 보이는 것을 확인하였다. 변비가 유발된 실험동물의 혈청 중성지방, 총 콜레스테롤 함량, HDL-콜레스테롤 함량에는 유산균 투여 유무 및 유산균의 농도에 대한 영향을 크게 받지 않은 것으로 보여진다. 고농도의 유산균을 섭취시킨 실험동물군(HIG)의 경우, 분변으로 유도된 아세트산과 프로피온산의 함량이 유의적으로 높게 나타났다. 또한 헤마톡실린 및 에오신 염색을 통한 장내 상피세포 관찰을 통해 유산균 분말 투여시 장 점막의 길이와 넓이가 유의적으로 증가하는 것을 확인하였다. 메타지노믹스 유전자 분석을 통한 미생물 분포의 상동성을 비교해 본 결과, 고농도의 유산균 투여군(HIG)이 정상대조군(NOR)과 가장 흡사한 분포 특성을 가지고 있음을 보여주었다. 이상의 결과에 따라 유산균 제제는 변비 개선 효과가 있다고 볼 수 있다.

• Food Science and Biotechnology
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• 제14권4호
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• pp.523-528
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• 2005

The commercial interests in functional foods containing probiotics are gaining significance in view of increasing studies on their role in digestive tract. Probiotic dairy foods containing health-promoting bacteria are important segment of functional food market. Various health benefits have been attributed to specific strains of lactic acid bacteria or food containing these probiotic cultures. Probiotic-containing foods are considered to improve general gut health and natural defenses of body, and lower blood cholesterol level. Specific probiotic microbes can alleviate or prevent diverse intestinal diarrhea-inducing disorders, cause prophylaxis of intestinal and urogenital infections, inhibit mutagenicity of intestinal contents, and reduce incidence of intestinal tumors. Recent increasing evidences on health effects of probiotics have triggered consumer interest in this category of functional foods. Rational approach needs to be applied in selection of strains for probiotic preparation to achieve required functionality. Present article focuses on some prominent probiotic candidates and criteria for their inclusion in functional food sector. Various health claims of probiotics on gastrointestinal disorders, anticarcinogenic effects, and anti-cholestrimic effects, and possible mechanistic explanations for their functionality are highlighted.

• Asian-Australasian Journal of Animal Sciences
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• 제17권6호
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• pp.863-868
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• 2004

Lectin activities and chemical characteristics of Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. originating from the porcine cecal mucosal layer were studied based on hemagglutination assay (HA) and hemagglutination inhibition assay (HIA). Although all the bacterial strains were able to agglutinate erythrocytes of porcine or rabbit origin, much higher HA titers were consistently observed for Lactobacillus spp. than for E. coli or for Bifidobacterium spp. A remarkable reduction in HA titers occurred by the treatment of E. coli and Lactobacillus spp. with protease or trypsin and of Bifidobacterium spp. with protease, trypsin or periodate. There were no significant effects on the HA titers of the three groups of bacteria after the treatment with lipase. Hemagglutination of E. coli was strongly inhibited by D (+)-mannose and D (+)-galactose; Lactobacillus spp. by $\alpha$-L-rhamnose and methyl-$\beta$-galactopyranoside; Bifidobacterium spp. by D (+)-alactose, $\alpha$-L-rhamnose, $\alpha$-L-fucose, L (+)-arabinose, D (+)-mannose, D (-)-fructose at a relatively low concentration (1.43 to 3.75 mg/ml). These results, combined with the enhanced HA activities of the three bacterial strains by modification of rabbit erythrocytes with neuraminidase and abolished HA activity of E. coli after treatment with $\beta$-galactosidase, indicate that it might be the glycoproteinous substances surrounding the surface of the bacterial cells that are responsible for the adhesions of these microorganisms by recognizing the specific receptors on the red blood cell.

• 한국미생물·생명공학회지
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• 제48권3호
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• pp.276-286
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• 2020

Probiotics are live microorganisms that, when administered in adequate amounts, confer health benefits to the host. This study was conducted for the isolation of potential lactic acid bacteria (LAB) with probiotic properties from goat milk and yogurt. Several tests were conducted in vitro using the standard procedures for evaluating the inhibitory spectra of LAB against pathogenic bacteria; tolerance to NaCl, bile salt, and phenol; hemolytic, milk coagulation, and bile salt hydrolase activities; gastrointestinal transit tolerance; adhesion properties; and antibiotic susceptibility. Among 40 LAB strains screened according to culture characteristics, five isolates exhibited antagonistic properties. Three were identified as Pediococcus acidilactici, and two were identified as Enterococcus faecium, exploiting 16S rRNA gene sequencing. All the isolates succeeded in the gastrointestinal transit tolerance assay and successively colonized mucosal epithelial cells. Based on the results of these in vitro assays, both P. acidilactici and E. faecium can be considered as potential probiotic candidates.

• Natural Product Sciences
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• 제19권4호
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• pp.297-302
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• 2013

The current study was conducted to evaluate the antibacterial and antioxidant activities of the essential oil fraction from the roots of Angelica tenuissima Nakai and its main components. We extracted the essential oil fraction from the roots of A. tenuissima using steam distillation and isolated its main components. Their antibacterial activities were determined by broth dilution test against food-borne pathogenic bacteria. Antioxidant activities were evaluated by DPPH-scavenging assay and reducing-power test. Also tested was their ability to inhibit the growth of two gastrointestinal cancer cell lines, Caco-2 and MKN-45. The A. tenuissima oil fraction and its main components, ligustilide and butylidene phthalide exhibited marked inhibitory effects against most of the tested antibiotic-susceptible and antibiotic-resistant bacterial strains with minimum inhibiting concentrations (MICs) from $0.21{\pm}0.08$ to $3.60{\pm}0.89mg/ml$. They also showed growth-inhibiting activity against Caco-2 and MKN-45 cells. The oil fraction showed significant antioxidant activities in DPPH radical scavenging assay and reducing-power test. Taken together, A. tenuissima essential oil could be used as a safe additive for preventing food contamination by pathogenic bacteria. Additionally, its antioxidative activity and the ability to inhibit gastrointestinal carcinoma cell lines could increase its value for functional foods and prevention of cancer.

• Journal of Dairy Science and Biotechnology
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• 제21권2호
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• pp.125-137
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• 2003

Bifidobacteria are normal inhabitants of the human gastrointestinal tract throughout lift, starting just days after birth, and are one of several predominant species of the colonic microflora, along with Peptostreptococcus, Eubacteria, Clostridia, and Bacteroides. Bifidobacteria differ from lactic acid bacteria in that they produce not only lactic acid but also acetic acid as major fermentation products. The classification of bifidobacteria has changed numerous times since they were discovered in 1899 in the feces of breast-fed infants. Since 1994, three additional species have been included in the list (B. lactis, B. inopinatum, and B. denticolens), with a current total of 32 species. A variety of probiotic effects of bifidobacteria are currently being investigated. Research reports suggests several potential probiotic advantages, in particular antimicrobial effects, immune-modulation reduction of the cancer risk, and modulation of gastrointestinal flora. As technological challenges related to viability and enumeration are being overcome, milks fermented with these anaerobic microorganisms(alone or in combination with lactic acid bacteria) are more able to provide consistently satisfying with large numbers of viable microorganisms. Over 70 products containing bifidobacteria are currently offered around the world, including fermented milks, cheese, buttermilk frozen desserts, candy, and pharmaceutical preparations.

• 한국식품영양학회지
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• 제30권3호
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• pp.395-404
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• 2017

Probiotics may be defined as microbial agents that can benefit humans and have been used primarily by mankind in fermented foods. A representative of probiotics is lactic acid bacteria (LAB), which has received attention recently due to its perceived health benefits. We reviewed research papers about Bifidobacerium and Lactobacillus, which are two of the most known of the LAB. Bifidobacerium alleviates diarrhea from various causes by improving intestinal microflora, and it has been reported that it reduces Helicobacter pylori bacteria known as the cause of gastric ulcer and stomach cancer. Bifidobacerium has also reported to be effective on immunization and allergy, reduce blood cholesterol, cancer, lactose intolerance. Lactobacillus alleviates diarrhea but has not fully demonstrated its effectiveness relative to other health issues. Several lactic acid bacteria and yeast are expected to act as probiotics, so, in the future, more research on the health benefits of lactic acid bacteria is needed.

• Journal of Microbiology and Biotechnology
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• 제17권8호
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• pp.1227-1235
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• 2007

Lactic acid bacteria (LAB) provide several potential health and nutritional benefits, including improving the nutritional value of food, controlling serum cholesterol levels, and controlling some types of cancer. Numerous in vitro, in vivo, human, and epidemiological studies have provided evidence of the chemopreventive effects of LAB on colon, bladder, liver, breast, and gastric cancers. These effects act via diverse mechanisms, including alteration of the gastrointestinal micro flora, enhancement of the host's immune response, and antioxidative and antiproliferative activities. This review discusses the recent progresses on the chemopreventive effects of LAB on specific cancer types and the underlying molecular mechanisms.