Biofilm is a community of microorganisms that adhere to abiotic or biotic surfaces, and is problematic in a wide range of food industries, as well as to human health. Although bacteriocin from lactic ...acid bacteria is well known as a natural antimicrobial agent in food preservation, it has been poorly investigated that bacteriocin inhibits the biofilm formation of foodborne pathogens. In this study, we demonstrated that bacteriocin produced by Lactobacillus brevis DF01 was partially purified and investigated whether the bacteriocin inhibited the biofilm formation of Escherichia coli and Salmonella Typhimurium. Assessment by the microtiter plate method, as well as by fluorescence and scanning electron microscopy, showed that the biofilm formation of E. coli and S. Typhimurium was reduced when the bacteria was co-incubated with crude bacteriocin of L. brevis DF01 (DF01 bacteriocin). Although pre-treated DF01 bacteriocin also significantly inhibited the biofilm formation of E. coli and S. Typhimurium (P = 0.0035 and P = 0.0003, respectively) post-treatment with DF01 bacteriocin did not significantly inhibit the biofilm formation (P = 0.1314 for E. coli and P = 0.2939 for S. Typhimurium), suggesting that DF01 bacteriocin interfered with biofilm formation, but did not disrupt the established biofilm of E. coli and S. Typhimurium. In addition, biofilms of both E. coli and S. Typhimuriun on the surface of stainless steel coupons were decreased in the presence of DF01 bacteriocin. Taken together, these results suggest that DF01 bacteriocin may be applied to control the biofilm formation of E. coli and S. Typhimurium.
•L. brevis DF01 bacteriocin inhibits the formation of biofilms of E. coli and S. Typhimurium.•The bacteriocin interferes with the growth of E. coli at early incubation period.•S. Typhimurium is inhibited by the bacteriocin at late incubation period.•Biofilms of both pathogens on stainless steel are inhibited by the bacteriocin.
Entrepreneurs involved in the commercialization of natural products are currently displaying significant interests in herbal drugs, medicines, and natural product-based herbal products. A broad range ...of bioactive chemical compounds have been derived from medicinal plants, either in their pure form or as homogenous extracts. As these compounds have broad structural and functional diversities, they offer pharmaceutical companies numerous opportunities for the development of new drug leads. They also represent an excellent source of molecules for the production of food additives, functional foods, nutritional products, and nutraceuticals for the growing number of natural food companies.
A number of bioactive compounds, including polyphenols, are present in high concentrations in plant species whereas a number of other important compounds such as saponin are present at very low levels. Several identification, extraction, and isolation techniques are currently used to extract bioactive compounds from plants. However, as these techniques are generally laborious and very expensive, there is an urgent need for new advanced techniques for identification, extraction, and isolation of plant bioactive compounds in quantities sufficient for their potential applications in various sectors.
The aim of this review is to collate and present information on the identification, extraction, and isolation of the most widely used bioactive compounds from selected commercial medicinal plants, thereby providing a useful resource for medicinal scientists and pharmaceutical and food-related industries seeking to generate high yields at low cost to meet market requirements.
•Few medicinal plants are effective and commercially beneficial.•Identification, isolation, & extraction of bioactive compounds is tedious task.•A number of techniques are currently utilized to extract these bioactive compounds.•Current procedure for extraction & characterization from selected commercial plant.•Documentation of suitable techniques for increasing yield with future applications.
The aim of the present study was to investigate the antiinflammatory and antibiofilm effects of whey fermented by Enterococcus faecalis M157 (M157-W) against oral pathogenic bacteria. The M157-W ...significantly inhibited IL-1β, IL-6, and nitric oxide induced by the lipopolysaccharide of Porphyromonas gingivalis in RAW 264.7 cells. The M157-W also inhibited the production of IL-1β and IL-8 in human periodontal ligament cells. Treatment with M157-W suppressed the phosphorylation of mitogen-activated protein kinases as well as the activation of nuclear factor-κB in RAW 264.7 cells stimulated by P. gingivalis lipopolysaccharide. Furthermore, M157-W dose-dependently inhibited Streptococcus mutans biofilm, whereas unfermented whey did not inhibit the biofilm. Treatment with M157-W significantly suppressed gtfB, gtfC, and gtfD gene expression in S. mutans compared with the control (0 μg/mL), indicating that M157-W inhibits S. mutans biofilm formation by reducing the synthesis of extracellular polymeric substances. Collectively, these results suggest that M157-W has antiinflammatory and antibiofilm activities against oral pathogenic bacteria.
•Cell-free supernatant (CFS) of P. acidilactici inhibits the growth of C. albicans.•P. acidilactici CFS strongly decreases the biofilm formation of C. albicans.•Acidic condition of P. acidilactici ...CFS may be associated with the inhibition.•P. acidilactici may be used as an antifungal agent to control C. albicans.
The aim of this study was to investigate the antifungal activities of cell-free supernatants of a probiotic strain, Pediococcus acidilactici HW01, against Candida albicans.
C. albicans was cultured in the presence of different concentration of cell-free supernatants obtained from P. acidilactici HW01 (HW01 CFS) and the growth of C. albicans was determined. C. albicans was incubated with HW01 CFS for 24 h and the biofilm formation of C. albicans was determined by staining crystal violet and by using a scanning electron microscope. Biofilm quantification was determined by 2, 3-Bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay.
HW01 CFS inhibitedC. albicans growth, whereas bacteriocin, which is a well-known antimicrobial peptide of lactic acid bacteria, failed to inhibit C. albicans growth. Pre-treatment and simultaneous treatment with HW01 CFS exhibited a significant inhibition of C. albicans biofilm. Although post-treatment with HW01 CFS did not disrupt the established biofilm of C. albicans at 3 h-incubation, significant reduced C. albicans biofilm was observed after 6 h-incubation in the presence of HW01 CFS.
These results suggested that the CFS fromP. acidilactici HW01 was revealed as an effective antifungal agent against C. albicans by reducing the growth and biofilm formation.
Salmonella biofilms are responsible for contamination in food processing environments as well as serious foodborne diseases. In this study, bacteriocins purified from Pediococcus acidilactici K10 ...(bacteriocin K10) and HW01 (bacteriocin HW01) strains were investigated for their potential to inhibit Salmonella Typhimurium biofilm. Both bacteriocins significantly inhibited the biofilm formation of S. Typhimurium by crystal violet staining method (P < 0.05). Fluorescence and scanning electron microscopy analyses confirmed that the S. Typhimurium biofilm was reduced in the presence of bacteriocins. After the biofilm formation of S. Typhimurium for 1–24 h, both bacteriocins K10 and HW01 exhibited similar patterns of decreased viability of S. Typhimurium biofilm cells up to 24 h (P < 0.05). The growth of S. Typhimurium planktonic cells was also significantly inhibited by treatment with bacteriocin K10 at 24 h and by treatment with bacteriocin HW01 at 12 and 24 h (P < 0.05). Furthermore, S. Typhimurium biofilm on the surfaces of stainless steel and chicken meat was effectively reduced by the treatment with both bacteriocins K10 and HW01. These results suggest that the bacteriocins of P. acidilactici could be effective anti-biofilm agents to control S. Typhimurium contamination in food matrices and food processing facilities.
•P. acidilactici bacteriocins inhibit the biofilm of S. Typhimurium.•The bacteriocins also reduce the growth of S. Typhimurium planktonic cells.•The biofilm is interfered at early time points after bacteriocin treatment.•The biofilm on stainless steel and chicken meat is inhibited by the bacteriocins.
In this study, antagonistic activities and probiotic potential of lactic acid bacteria (LAB) derived from a plant-based fermented food, kimchi, were demonstrated. The cell free supernatants (CFS) ...from
KCCM 43119,
KCCM 43060,
KCTC 3746, and
KCCM 41517 completely inhibited the growth of foodborne pathogenic bacteria, while neutralized CFS (pH 6.5) partially inhibited the growth. The competition, exclusion, and displacement of foodborne pathogenic bacteria by the LAB strains from adhesion to HT-29 cells were investigated. The LAB strains were able to compete with, exclude, and displace the foodborne pathogenic bacteria. However, the degree of inhibition due to the adhesion was found to be a LAB strain-dependent phenomenon. The LAB strains showed high coaggregation with foodborne pathogenic bacteria, and they also exhibited high resistance to acidic condition. Except
KCTC 3746, all LAB strains were capable of surviving in the presence of bile salts. Furthermore, while all LAB strains were resistant to chloramphenicol, kanamycin, streptomycin, gentamicin, and erythromycin, only
KCTC 3746 and
KCCM 41517 displayed resistance to vancomycin. These results suggest that the LAB strains derived from kimchi exerted antagonistic activities against foodborne pathogenic bacteria with probiotic potential.
Lipoteichoic acid (LTA), a major cell wall component of Gram-positive bacteria, is associated with various inflammatory diseases ranging from minor skin diseases to severe sepsis. It is known that ...LTA is recognized by Toll-like receptor 2 (TLR2), leading to the initiation of innate immune responses and further development of adaptive immunity. However, excessive immune responses may result in the inflammatory sequelae that are involved in severe diseases such as sepsis. Although numerous studies have tried to identify the molecular basis for the pathophysiology of Gram-positive bacterial infection, the exact role of LTA during the infection has not been clearly elucidated. This review provides an overview of LTA structure and host recognition by TLR2 that leads to the activation of innate immune responses. Emphasis is placed on differential immunostimulating activities of LTAs of various Gram-positive bacteria at the molecular level.
Periodontitis is an oral infectious disease caused by various pathogenic bacteria, such as
. Although probiotics and their cellular components have demonstrated positive effects on periodontitis, the ...beneficial impact of peptidoglycan (PGN) from probiotic
remains unclear. Therefore, our study sought to investigate the inhibitory effect of PGN isolated from
(LrPGN) on
-induced inflammatory responses. Pretreatment with LrPGN significantly inhibited the production of interleukin (IL)-1β, IL-6, and CCL20 in RAW 264.7 cells induced by
lipopolysaccharide (LPS). LrPGN reduced the phosphorylation of PI3K/Akt and MAPKs, as well as NF-κB activation, which were induced by
LPS. Furthermore, LrPGN dose-dependently reduced the expression of Toll-like receptor 4 (TLR4), indicating that LrPGN inhibits periodontal inflammation by regulating cellular signaling cascades through TLR4 suppression. Notably, LrPGN exhibited stronger inhibition of
LPS-induced production of inflammatory mediators compared to insoluble LrPGN and proteinase K-treated LrPGN. Moreover, MDP, a minimal bioactive PGN motif, also dose-dependently inhibited
LPS-induced inflammatory mediators, suggesting that MDP-like molecules present in the LrPGN structure may play a crucial role in the inhibition of inflammatory responses. Collectively, these findings suggest that LrPGN can mitigate periodontal inflammation and could be a useful agent for the prevention and treatment of periodontitis.
Biotransformation is an effective system to provide various beneficial effects in food processing and pharmaceutical fields. The present study evaluated the anti-bacterial and anti-inflammatory ...activities of lactic acid bacteria (LAB)-biotransformed mulberry fruit extract (MFE) against Salmonella Typhimurium. Biotransformed MFE more effectively reduced S. Typhimurium growth compared to non-biotransformed MFE and significantly inhibited the biofilm formation of S. Typhimurium (P < 0.05) from an early time point. The viability of S. Typhimurium biofilm cells was decreased in the presence of biotransformed MFE, as further evidenced by scanning electron microscopy analysis. In addition, biotransformed MFE significantly inhibited the secretion of interleukin-8 by S. Typhimurium in human intestinal epithelial cells in a dose-dependent manner (P < 0.05), indicating that biotransformed MFE effectively attenuated the inflammatory response in vitro. Thus, these results suggest that LAB-biotransformed MFE efficiently exhibited anti-bacterial activity by reducing the growth and biofilm formation of S. Typhimurium as well as anti-inflammatory activity in the intestinal epithelial cells infected with the bacteria.
•Mulberry fruit extract (MFE) is biotransformed by lactic acid bacteria (LAB).•LAB-biotransformed MFE inhibits the bacterial growth of S. Typhimurium.•LAB-biotransformed MFE reduces S. Typhimurium biofilm.•S. Typhimurium-induced IL-8 is attenuated by LAB-biotransformed MFE.
PDF
