• Food Science of Animal Resources
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• v.26 no.4
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• pp.497-502
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• 2006

The adhesion of 16 bifidobacterial strains, including 10 isolates from Korea infants, to Caco-2 cells and their cell surface hydrophobicity were tested. The results of adhesion and cell surface hydrophobicity of for various bifidobacterial strains were obtained and correlations between adhesion and hydrophobicity were strain-dependent properties. Any correlations between species of tested strains were not observed. Among the tested strains, Bifidobacterim longum D6, B. longum H4, B. thermophilum ATCC 25525, B. suis ATCC 27533, and B. animalis subsp. lactis BB12 had higher adherent properties and B. bifidum B3, B. longum D6, B. longum stronger hydrophobicity, respectively. Due to the strain-dependant correlation between adhesion to Caco-2 cells and cell surface hydrophobicity of bifidobacteria, these results provide a possible method for preliminary selection of bifidobacteria potentially adherent to Caco-2 cells by means of cell surface hydrophobic properties.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.343-349
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• 2009

Inhibitory effect of Escherichia coli O157 adhered to Caco-2 cells by the cells of Lactobacillus plantarum K11 and the cell-free culture supernatant (CFCS) and bacteriocin prepared from this strain was investigated. As the cell counts of viable L. plantarum K11 previously adhered to Caco-2 were increased, the rate of adhesion and adherent cell counts of E. coli O157 was lower. However, because the heated L. plantarum K11 rarely have the adhesion ability to Caco-2, the adhesion rate and adherent cell counts of E. coli O157 were high. In addition, the inhibitory effects of E. coli O157 adhesion by the CFCS and bacteriocin of L. plantarum K11 were dose-dependent manner. Therefore, the inhibition of adhesion of E. coli O157 to Caco-2 may result from the antimicrobial substances such as lactic acid and bacteriocin. Moreover the inhibitory activity of adhesion by the heated bacteriocin for 30 min at 100oC was similar to activity of non-treated bacteriocin, but the activity was disappeared by treatment with protease.

• Journal of Microbiology and Biotechnology
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• v.13 no.2
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• pp.276-281
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• 2003

The adhesion of probiotic bacteria to the intestinal mucosa is one of the desirable properties for their colonization in the intestinal tract, where these bacteria constantly compete with other bacteria. The adhesion of different strains of bifidobacteria to Caco-2 cells was compared. Among the strains examined, BGN-4 showed the highest adhesion level and the greatest cell surface hydrophobicity (CSH). No close relationship was found between the adhesion and CSH of the strains. Upon protease and heat treatment, the adhesion of the BGN-4 to the Caco-2 cells decreased significantly. The cells grown at $42^{\circ}C$ showed a lower CSH and self-aggregation levels than cells grown at $37^{\circ}C$. The treatment of EGTA did not have any effect on the adhesion. The degree of adhesion did not differ among the experimental groups in which galactose, mannose, or fucose were added in the adhesion assay mixture. The results suggest that the adhesion of the Bifidobacterium to the epithelial cells may be affected by the composition and structure of the cell membrane and interacting surfaces.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1731-1739
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• 2012

In this study, seven strains isolated from mustard leaf kimchi were screened for their tolerance to simulated gastric and bile juices, the adhesive properties to Caco-2 cells, and the inhibition ability of Salmonella Typhimurium ATCC 29631 adhesion. Lactobacillus acidophilus GK20, Lactobacillus paracasei GK74, and Lactobacillus plantarum GK81, which were resistant to bile as well as gastric juices, possessed high bile-salt hydrolase (BSH) activity towards both sodium glycocholate and sodium taurocholate. The strongest in vitro adherence of $53.96{\pm}4.49%$ was exhibited by L. plantarum GK81 followed by L. acidophilus GK20 with adhesion levels of $40.72{\pm}9.46%$. The adhesion of these strains was significantly (p < 0.05) reduced after exposure to pepsin and heating for 30 min at $80^{\circ}C$. Addition of $Ca^{2+}$ led to a significant (p < 0.05) increase of the adhesion of L. acidophilus GK20, but the adhesion ability of L. plantarum GK81 was not different from the control by the addition of calcium. In the competition and exclusion experiment, the adhesion inhibition of S. Typhimurium by L. plantarum GK81 strain was much higher than the other strains. Moreover, the exclusion inhibition of S. Typhimurium by L. acidophilus GK20 was considerably high, although the inhibition activity of this strain was lower than L. plantarum GK81.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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• pp.751-755
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• 2006

Dadih is Indonesian traditional fermented buffalo milk believed by the natives to have beneficial effects on human health. This may be due to the probiotic properties possessed by the lactic acid bacteria (LAB) involved in its fermentation process. It was discovered that ten strains of dadih lactic isolates possessed some probiotic properties in vitro. In this study, the adhesion properties of dadih LAB, in comparison with documented probiotic strains, were investigated in vitro by using mucin extracted from human faeces and Caco-2 cells as the models for human intestinal mucosal surface and intestinal cells respectively. The adhesion results showed the distinction of Lactobacillus reuteri IS-27560 in adhering to both mucus layer and Caco-2 cells. The competition assay for adhesion to the mucus layer between dadih LAB and selected pathogens indicated the competence of Lactococcus lactis IS-16183 and Lactobacillus rhamnosus IS-7257 in significantly inhibiting the adhesion of Escherichia coli O157:H7. Accordingly, these two strains may be potential candidates for use as probiotic strains. Overall, the adhesion properties of all dadih LAB strains were relatively comparable to that of Lactobacillus casei Shirota and Lactobacillus rhamnosus GG, the documented probiotic strains.

• Journal of Microbiology and Biotechnology
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• v.19 no.2
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• pp.178-186
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• 2009

To examine their potential as probiotics, acid and bile tolerance, antibiotics resistance, adhesion capacity to Caco-2 and HT-29, and antibacterial activity, of LAB isolated from Korean fermented foods such. as dongchimi, kimchi, Meju, and doenjang were assayed against foodborne pathogenic bacteria. DC 55, DC 136, DC 222, KC 21, KC 24, KC 34, KC 43, KC 117, MJ 54, MJ 301, SP 33, and SP 170 strains were resistant to acid and bile conditions. In particular, DC 55, DC 136, KC 24, KC 43, and MJ 301 strains were highly resistant to higher than 20 ${\mu}g/ml$ concentrations of vancomycin, streptomycin sulfate, or amoxicillin, whereas, DC 222, KC 21, KC 34, KC 117, MJ 54, and SP 33 strains were susceptible to lower than 2 ${\mu}g/ml$ concentrations of those antibiotics. The adhesion to HT-29 and Caco-2 cells varied with the strains tested in a strain-dependent manner. The highest level of adhesion was observed with DC 55, KC 21, KC 24, and MJ 301 strains, having higher than 50% of adhesion to HT-29 or Caco-2 cells. In addition, Staphylococcus aureus was the most sensitive to KC 21, showing an inhibition of about 70%, and the antibacterial activity of KC 21 against S. aureus resulted most likely from both organic acids and bacteriocin. Based on its phenotypic characteristics and utilization of various sugars, the KC 21 strain was identified as Lactobacillus plantarum.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.581-585
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• 2005

Five lactic acid bacteria (LAB) including 2 Lactobacillus strains isolated from Kimchi were evaluated to determine the binding ability to Caco-2 cells and $AFB_1$. LAB were divided into three different groups ; viable, heat-treated, and acid-treated cells. In the radioactive-labeling assay for bound cell counting, viable Lactobacillus Plantarum KCTC 3099 showed the higher adhesion to Caco-2 cells with the binding capacity of $39.2\%$, which was $149\%$ higher than Lactobacillus rhamnosus GG as a positive control. Leuconostoc mesenteroids KCTC 3100 showed the similar binding ability to L. rhamnosus GG. After 1 hour incubation at $37^{\circ}C$ with $AFB_1$, viable L. Planterum KTCC 3099 removed the toxin by $49.8\%$, which was similar level to L. rhamnosus GG. Both heat- and acid-treated groups showed high binding effect but acid-treated group was more effective for both Caco-2 cell binding and $AFB_1$ removal than the other. These results indicate that components of bacterial cell wall might be involved in tile binding to intestinal cells and toxins.

• Microbiology and Biotechnology Letters
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• v.49 no.2
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• pp.157-166
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• 2021

The probiotic market is constantly continuing to grow, concomitantly with a widening in the range and diversity of probiotic products. Probiotics are defined as live microorganisms that provide a benefit to the host when consumed at a proper dose; the viability of a probiotic is therefore of crucial importance for its efficacy. Many products undergo lyophilization for maintaining their shelf-life. Unfortunately, this procedure may damage the integrity of the cells due to stress conditions during both the freezing and (vacuum-) drying process, thereby impacting their functionality. We propose a lysine-based mixture for rehydration of freeze-dried probiotics for improving their viability during in vitro simulated gastric and duodenum stress conditions. Measurement of the zeta potential served as an indicator of cell integrity and efficacy of this mixture, while functionality was estimated by adhesion to a human enterocyte-like Caco-2 cell-line. The freeze-dried bacteria exhibited a significantly different zeta potential compared to fresh cultures; however, this condition could be restored by rehydration with the lysine mixture. Recovery of the surface charge was found to influence adhesion ability to the Caco-2 cell-line. The optimum lysine concentration of the formulation, designated "Zeta-bio", was found to be 0.03 M for improving the viability of Lactiplantibacillus plantarum Lp-115 by up to 13.86% and a 7-strain mixture (400B) to 41.99% compared to the control rehydrated with distilled water. In addition, the lysine Zeta-bio formulation notably increased the adherence ability of lyophilized Lp-115 to the Caco-2 cell-line after subjected to the in vitro stress conditions of the simulated gastrointestinal tract passage.

• Microbiology and Biotechnology Letters
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• v.50 no.1
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• pp.51-62
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• 2022

Lactobacillus rhamnosus SKG34 (LrSKG34), a potential probiotic strain, was successfully isolated from Sumbawa Mare's milk. Our previous studies showed that the strain is resistant to gastrointestinal conditions, possesses antioxidant activity, and lowers blood cholesterol levels. Further clarification of the potential probiotic characteristics and safety assessment are necessary. This study aimed to evaluate the adhesion of LrSKG34 to Caco-2 cell monolayers and its effect on mucosal integrity in vitro. We also examined the LrSKG34 safety profile based on antimicrobial susceptibility testing, haemolytic activity determination, Caco-2 cell monolayer translocation evaluation, and in vivo investigation of the effect of LrSKG34 on the physiology, biochemical markers, and histopathological appearance of major organs in an animal model. LrSKG34 attached to Caco-2 cell monolayers and maintained mucosal integrity in vitro. The typical resistance of lactobacilli to ciprofloxacin, gentamicin, vancomycin, trimethoprim-sulfamethoxazole, and metronidazole was confirmed for LrSKG34. No haemolytic activity was observed on blood agar plates, and no LrSKG34 translocation was observed in Caco-2 cell monolayers. Administration of LrSKG34 to Sprague-Dawley rats did not adversely affect body weight. No abnormalities in hematological parameters, serum biochemistry levels, or histopathological structures of major organs were observed in LrSKG34-treated rats. Collectively, the results implicate LrSKG34 as a promising and potentially safe probiotic candidate for further development.

• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.1013-1018
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• 2009

The identification and characterization of Bacillus polyfermenticus KJS-2 (B. polyfermenticus KJS-2) was conducted using TEM, an API 50CHB kit, 16S rDNA sequencing, a phylogenetic tree, and catalase and oxidase testing. The conversion rate of glucose to lactic acid by B. polyfermenticus KJS-2 was found to be $60.7{\pm}4.9%$. In addition, treatment of B. polyfermenticus KJS-2 with artificial gastric juice (pH 2.0) and bile acid (pH 6.5) for 4 h resulted in a final viability of $140{\pm}7.9%$ and $108{\pm}3.5%$, respectively. Finally, the results of adhesion experiments using Caco-2 cells revealed that the adherence of B. polyfermenticus KJS-2 to Caco-2 cells was approximately $65{\pm}0.6%$.