• Food Science and Preservation
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• v.30 no.3
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• pp.538-545
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• 2023

This study aimed to assess the in vitro safety of a probiotics mixture (Lactobacillus acidophilus PBS066, Lactiplantibacillus plantarum PBS067, and Limosilactobacillus reuteri PBS072), along with its inhibitory effect on carbohydrate digestion. All three strains met the antibiotic resistance profile of the European Food Safety Authority (EFSA) guidelines. None of the strains exhibited hemolytic activity or cytotoxicity against Caco-2 cells. Strains PBS067 and PBS072 inhibited α-amylase activity, whereas all three strains suppressed α-glucosidase activity, indicating that the mixture might limit carbohydrate digestion in the gastrointestinal tract. These findings support the safety of this probiotics mixture and its potential to modulate carbohydrate metabolism in the gut.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.673-680
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• 2009

This study was conducted to screen for plant food materials that improve human intestinal microflora, especially microorganisms associated with obesity. Among 30 tested plant food materials, the extract of Schizandra chinensis inactivated Eubacterium limosum, Bacteroides fragilis and Clostridium spp. Additionally, S. chinensis extract was also found to have a growth-promoting effect on Bifidobacterium spp.. The antimicrobial activity and antioxidant activity of the water extract did not decrease in respond to heating. Additionally, the water extract of S. chinensis did not show a toxic effect on the growth of Caco-2 cells. In vivo feeding tests were performed to investigate the influence of extract on the intestinal microflora in rats. Although the extract did not reduce obesity induced by a high fat diet, it led to significant increase in the population of Bifidobacterium spp. and a decrease in the population of Clostridium spp. in rats. Taken together, these results indicate that S. chinensis could be useful as a functional food component to control intestinal microbial flora.

• Journal of Microbiology and Biotechnology
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• v.27 no.11
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• pp.1971-1982
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• 2017

Piliated Lactobacillus rhamnosus (pLR) strains possess higher adherent capacity than non-piliated strains. The objective of this study was to isolate and characterize probiotic pLR strains in human fecal samples. To this end, mouse polyclonal antiserum (anti-SpaA) against the recombinant pilus protein (SpaA) of L. rhamnosus strain GG (LGG) was prepared and tested for its reactivity and specificity. With the anti-SpaA, a method combining the de Man, Rogosa, and Sharpe (MRS) agar plating separation and colony immunoblotting (CIB) was developed to isolate pLR from 124 human fecal samples. The genetic and phenotypic characteristics of the resultant pLR isolates were compared by randomly amplified polymorphic DNA (RAPD) fingerprinting, and examination of adhesion to Caco-2 cells, hydrophobicity, autoaggregation, and in vitro gastrointestinal tolerance. Anti-SpaA specifically reacted with three pLR strains of 25 test strains, as assessed by western blotting, immunofluorescence flow cytometry, and immunoelectron microscopy (IEM) assays. The optimized MRS agar separation plus anti-SpaA-based CIB procedure could quantitatively detect $2.5{\times}10^3CFU/ml$ of pLR colonies spiked in $10^6CFU/ml$ of background bacteria. Eight pLR strains were identified in 124 human fecal samples, and were confirmed by 16S RNA gene sequencing and IEM identification. RAPD fingerprinting of the pLR strains revealed seven different patterns, of which only two isolates from infants showed the same RAPD profiles with LGG. Strain PLR06 was obtained with high adhesion and autoaggregation activities, hydrophobicity, and gastrointestinal tolerance. Anti-SpaA-based CIB is a rapid and inexpensive method for the preliminary screening of novel adherent L. rhamnosus strains for commercial purposes.

• Korean Journal of Food Science and Technology
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• v.50 no.5
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• pp.549-554
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• 2018

The objective of the current study was to evaluate the antioxidant activity of ethanol extracts from common and tartary buckwheat milling fractions (hull, bran, and flour). The results indicated that total polyphenol and flavonoid contents were higher in tartary buckwheats than in common buckwheats, which was related to high rutin levels. In particular, the highest rutin content was detected in the bran fraction. ABTS and DPPH radical scavenging activities of tartary buckwheats were higher than those of common buckwheats, especially in bran. Cellular antioxidant activity of tartary buckwheat milling fractions was more pronounced than that of common buckwheat in both Caco-2 and Raw 264.7 cells, demonstrating the higher cellular antioxidant effect of tartary buckwheat bran. The cytotoxic effect of both common and tartary buckwheat milling fractions on cell proliferation was not significant. These results suggest that tartary buckwheat bran may have much potential for usefulness in protective and therapeutic antioxidant applications.