scholarly journals Biofilm formation and antagonistic activity of Lacticaseibacillus rhamnosus (PTCC1712) and Lactiplantibacillus plantarum (PTCC1745)

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zeinab Rezaei ◽  
Saeid Khanzadi ◽  
Amir Salari

AbstractCurrently, the health benefits of probiotic bacteria are well known, and this has taken up a great deal of space in food science and health, both research and operational. On the other hand, anti-biofilm properties on food pathogens in the food and pharmaceutical industries have created an attractive challenge. This study aimed to describe the inhibitory activity of cell-free supernatants (CFS), planktonic cells, and biofilm form of lactobacilus strains (L. rhamnosus and L. plantarum) against food pathogens such as Pseudomonas aeruginosa and Listeria monocytogenes. Anti-bacterial activities of the CFS of lactobacillus strains were assessed by the microplate method and via violet staining. Evaluation of the antagonistic activity of planktonic cells and biofilm of LAB were performed by the spread plate method. The results showed the incubation time of 48 h was the best time to produce biofilm. Although the planktonic states reduce the pathogens bacterial about 1 –1.5 log, but in biofilm forms, decreased L. monocytogenes about 4.5 log compared to the control, and in the case of P. aeruginosa, a growth reduction of about 2.13 log was observed. Furthermore, biofilm formation of L. monocytogenes in the presence of L. rhamnosus cell-free supernatant was more weakly than L. plantarum CFS, but their CFS effect on reducing the bacterial population of P. aeruginosa was the same. According to the study, biofilm produced by probiotic strains can be considered a new approach for biological control. Also, cell-free supernatant can be used as postbiotic in the food and pharmaceutical industries.

2021 ◽  
Vol 12 ◽  
Author(s):  
Mahtab Hassanpour Tazehabadi ◽  
Ammar Algburi ◽  
Igor V. Popov ◽  
Alexey M. Ermakov ◽  
Vladimir A. Chistyakov ◽  
...  

Salmonellosis is a foodborne infection caused by Salmonella. Domestic poultry species are one of the main reservoirs of Salmonella, which causes the foodborne infection salmonellosis, and are responsible for many cases of animal-to-human transmission. Keeping backyard chickens is now a growing trend, increasing the frequency of direct contact with the flock and, by consequence, the incidence of Salmonella infections. Bacillus subtilis KATMIRA1933 and Bacillus amyloliquefaciens B-1895 are probiotic bacilli that produce the bacteriocins subtilosin A and subtilin, respectively. The antimicrobial activity of the two strains was determined against the reference strain Micrococcus luteus ATCC 10420. The cell-free supernatant of B. subtilis KATMIRA1933 inhibited biofilm formation by Salmonella enterica subsp. enterica serovar Hadar, Salmonella enterica subsp. enterica serovar Enteritidis phage type 4, and Salmonella enterica subsp. enterica serovar Thompson by 51.1, 48.3, and 56.9%, respectively. The cell-free supernatant of B. amyloliquefaciens B-1895 inhibited the biofilm formation of these Salmonella strains by 30.4, 28.6, and 35.5%, respectively. These findings suggest that the bacillus strains may have the potential to be used as probiotics and antibiotic alternatives for the control of Salmonella in poultry. The number of planktonic cells was unaffected by treatment with the cell-free supernatant. A co-culture of the Salmonella strains with either bacilli showed no signs of growth inhibition, suggesting that it might have been quorum sensing that is affected by the two Bacillus strains.


Author(s):  
L. V. Gladysheva ◽  
S. V. Cherkasov

Literature data and results of authors’ research on biological properties of corynebacteria of reproductive tract of women are analyzed. General characteristics of microorganisms is given. 20 species of corynebacteria are presented: C. amycolatum, C. aquaticum, C. aurimucosum, C. bovis, C. glucuronolyticum, C: coyleae, C.freneyi, C.jeikeium var. genitalium, C.jeikeium var. pseudogeni-talium, C. lipophiloflavum, C. kutscheri, C. minutissimum, C. nigricans, C. pseudodiphtheriticum, C. pseudotuberculosis, C. renale, C. striatum, C. tuberculostearicum (lipophile) (includes most CDC group G-2 strains), C. xerosis and C. urealyticum. Mechanisms and factors ensuring the ability of corynebacteria to exist in vaginal biotope regardless of microecological condition - the presence ofhigh resistance to factors of innate immunity (lysozyme, complement, immunoglobulins), pH-dependent adhesion to fibronectin and vaginal epitheliocytes - are examined. The role of fi-bronectin in adhesion of bacteria to vaginal epithelial cells is described. Corynebacteria exometabolites are shown to facilitate maximal realization of antagonistic activity of vaginal peroxide-producing lactobacilli by supressing catalase of opportunistic microorganisms-symbionts, that directly influences the quantity and structure of bacterial population by suppressing growth and biofilm-formation. The materials provided give evidence on the significant role of corynebacteria in realization of physiological phenomenon - colonization resistance and allow us to examine these microorganisms as an integral part of normal microbiota of woman reproduction tract.


2011 ◽  
Vol 56 (1) ◽  
pp. 148-153 ◽  
Author(s):  
Marisa H. Miceli ◽  
Stella M. Bernardo ◽  
T. S. Neil Ku ◽  
Carla Walraven ◽  
Samuel A. Lee

ABSTRACTInfections and thromboses are the most common complications associated with central venous catheters. Suggested strategies for prevention and management of these complications include the use of heparin-coated catheters, heparin locks, and antimicrobial lock therapy. However, the effects of heparin onCandida albicansbiofilms and planktonic cells have not been previously studied. Therefore, we sought to determine thein vitroeffect of a heparin sodium preparation (HP) on biofilms and planktonic cells ofC. albicans. Because HP contains two preservatives, methyl paraben (MP) and propyl paraben (PP), these compounds and heparin sodium without preservatives (Pure-H) were also tested individually. The metabolic activity of the mature biofilm after treatment was assessed using XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] reduction and microscopy. Pure-H, MP, and PP caused up to 75, 85, and 60% reductions of metabolic activity of the mature preformedC. albicansbiofilms, respectively. Maximal efficacy against the mature biofilm was observed with HP (up to 90%) compared to the individual compounds (P< 0.0001). Pure-H, MP, and PP each inhibitedC. albicansbiofilm formation up to 90%. A complete inhibition of biofilm formation was observed with HP at 5,000 U/ml and higher. When tested against planktonic cells, each compound inhibited growth in a dose-dependent manner. These data indicated that HP, MP, PP, and Pure-H havein vitroantifungal activity againstC. albicansmature biofilms, formation of biofilms, and planktonic cells. Investigation of high-dose heparin-based strategies (e.g., heparin locks) in combination with traditional antifungal agents for the treatment and/or prevention ofC. albicansbiofilms is warranted.


2021 ◽  
Vol 16 (6) ◽  
pp. 1934578X2110196
Author(s):  
Zheng Liu ◽  
Lihua Zhang ◽  
Jincai Wang ◽  
Yanping Li ◽  
Yiqun Chang ◽  
...  

Biofilm formation is considered as a crucial factor in various oral diseases, such as dental caries. The quorum sensing (QS) signaling system was proved to have a crucial role in the microbial dental plaque biofilm formation of Streptococcus mutans ( S. mutans). LuxS was critical to regulating the QS system and survival of the bacterium, and, therefore, compounds which target LuxS may be a potential therapy for dental caries. The binding activities of 37,170 natural compounds to LuxS were virtually screened in this study. Baicalein and paeonol were chosen for further research of the binding mode and ΔG values with LuxS. Both baicalein and paeonol inhibited the biofilm formation without influence on the growth of S. mutans. Baicalein also distinctly reduced the production of both rhamnolipids and acids. The results provide us with a new approach to combat dental caries instead of the traditional use of antibacterial chemicals.


2003 ◽  
Vol 71 (8) ◽  
pp. 4759-4766 ◽  
Author(s):  
Keeta S. Gilmore ◽  
Pravina Srinivas ◽  
Darrin R. Akins ◽  
Kenneth L. Hatter ◽  
Michael S. Gilmore

ABSTRACT A model for the protracted (30-day) colonization of smooth surfaces by Streptococcus gordonii that incorporates the nutrient flux that occurs in the oral cavity was developed. This model was used to characterize the biphasic expansion of the adherent bacterial population, which corresponded with the emergence of higher-order architectures characteristic of biofilms. Biofilm formation by S. gordonii was observed to be influenced by the presence of simple sugars including sucrose, glucose, and fructose. Real-time PCR was used to quantify changes in expression of S. gordonii genes known or thought to be involved in biofilm formation. Morphological changes were accompanied by a significant shift in gene expression patterns. The majority of S. gordonii genes examined were observed to be downregulated in the biofilm phase. Genes found to be upregulated in the biofilm state were observed to encode products related to environmental sensing and signaling.


2016 ◽  
Vol 61 (2) ◽  
Author(s):  
Derek Fleming ◽  
Laura Chahin ◽  
Kendra Rumbaugh

ABSTRACT The persistent nature of chronic wounds leaves them highly susceptible to invasion by a variety of pathogens that have the ability to construct an extracellular polymeric substance (EPS). This EPS makes the bacterial population, or biofilm, up to 1,000-fold more antibiotic tolerant than planktonic cells and makes wound healing extremely difficult. Thus, compounds which have the ability to degrade biofilms, but not host tissue components, are highly sought after for clinical applications. In this study, we examined the efficacy of two glycoside hydrolases, α-amylase and cellulase, which break down complex polysaccharides, to effectively disrupt Staphylococcus aureus and Pseudomonas aeruginosa monoculture and coculture biofilms. We hypothesized that glycoside hydrolase therapy would significantly reduce EPS biomass and convert bacteria to their planktonic state, leaving them more susceptible to conventional antimicrobials. Treatment of S. aureus and P. aeruginosa biofilms, grown in vitro and in vivo, with solutions of α-amylase and cellulase resulted in significant reductions in biomass, dissolution of the biofilm, and an increase in the effectiveness of subsequent antibiotic treatments. These data suggest that glycoside hydrolase therapy represents a potential safe, effective, and new avenue of treatment for biofilm-related infections.


2010 ◽  
Vol 76 (7) ◽  
pp. 2122-2128 ◽  
Author(s):  
Mark Reuter ◽  
Arthur Mallett ◽  
Bruce M. Pearson ◽  
Arnoud H. M. van Vliet

ABSTRACT The microaerophilic human pathogen Campylobacter jejuni is the leading cause of food-borne bacterial gastroenteritis in the developed world. During transmission through the food chain and the environment, the organism must survive stressful environmental conditions, particularly high oxygen levels. Biofilm formation has been suggested to play a role in the environmental survival of this organism. In this work we show that C. jejuni NCTC 11168 biofilms developed more rapidly under environmental and food-chain-relevant aerobic conditions (20% O2) than under microaerobic conditions (5% O2, 10% CO2), although final levels of biofilms were comparable after 3 days. Staining of biofilms with Congo red gave results similar to those obtained with the commonly used crystal violet staining. The level of biofilm formation by nonmotile aflagellate strains was lower than that observed for the motile flagellated strain but nonetheless increased under aerobic conditions, suggesting the presence of flagellum-dependent and flagellum-independent mechanisms of biofilm formation in C. jejuni. Moreover, preformed biofilms shed high numbers of viable C. jejuni cells into the culture supernatant independently of the oxygen concentration, suggesting a continuous passive release of cells into the medium rather than a condition-specific active mechanism of dispersal. We conclude that under aerobic or stressful conditions, C. jejuni adapts to a biofilm lifestyle, allowing survival under detrimental conditions, and that such a biofilm can function as a reservoir of viable planktonic cells. The increased level of biofilm formation under aerobic conditions is likely to be an adaptation contributing to the zoonotic lifestyle of C. jejuni.


Author(s):  
N. Yu. Vasylieva ◽  
G. V. Yamborko ◽  
А. G. Merlich ◽  
I. V. Strashnova ◽  
I. P. Metelitsina

Purpose. To evaluate the effectiveness of bacteriocin of Enterococcus italicusONU 547 and essential oils individually and in combination against indicatorstrains of opportunistic pathogens. Methods. The antagonistic activity of essential oils and bacteriocin was determined by the optical density of the bacterial suspension of test strains (Salmonella enterica NCTC 6017, Escherichia coli АТСС 25922, Pseudomonas aeruginosa АТСС 27853, Pseudomonas putida KT 2440, Enterococcus faecalis АТСС 29212, Klebsiella pneumoniae АТСС 10031,Staphylococcus aureus АТСС 25923). The index of fractional inhibitory activity(FIC) was calculated by adding the FIC values of bacteriocin E. italicus ONU 547and the studied essential oils. The results. The maximum antimicrobial effect was caused by the essential oils of Anisum officinalis and Melissa officinalis, which suppressed the growth of test strains more than 50.0%. When using bacteriocin of E. italicus ONU 547 suppression of viability of indicator strains did not exceed 30.0%. Experimental combinations of essential oils and bacteriocin caused 4 types of consequences: synergy effect; additive effect; antagonistic effect; interactiveeffect (no interaction effect). In most cases, the combined action of bacteriocinand essential oils caused an additive effect. Conclusions. This study demonstrated the potential of using different combinations of natural antimicrobial compounds. The obtained results provide grounds for further development and optimization ofcombinations of essential oils and probiotic strains of microorganisms for use in food and pharmaceutical biotechnology.


2020 ◽  
Vol 69 (6) ◽  
pp. 830-837
Author(s):  
Raimunda Sâmia Nogueira Brilhante ◽  
José Alexandre Telmos Silva ◽  
Géssica dos Santos Araújo ◽  
Vandbergue Santos Pereira ◽  
Wilker Jose Perez Gotay ◽  
...  

Introduction. Cryptococcus species are pathogens commonly associated with cases of meningoencephalitis in individuals who are immunosuppressed due to AIDS. Aim. The aim was to evaluate the effects of the antiretroviral darunavir alone or associated with fluconazole, 5-flucytosine and amphotericin B against planktonic cells and biofilms of Cryptococcus species. Methodology. Susceptibility testing of darunavir and the common antifungals against 12 members of the Cryptococcus neoformans/Cryptococcus gattii species complex was evaluated by broth microdilution. The interaction between darunavir and antifungals against planktonic cells was tested by a checkerboard assay. The effects of darunavir against biofilm metabolic activity and biomass were evaluated by the XTT reduction assay and crystal violet staining, respectively. Results. Darunavir combined with amphotericin B showed a synergistic interaction against planktonic cells. No antagonistic interaction was observed between darunavir and the antifungals used. All Cryptococcus species strains were strong biofilm producers. Darunavir alone reduced biofilm metabolic activity and biomass when added during and after biofilm formation (P<0.05). The combination of darunavir with antifungals caused a significant reduction in biofilm metabolic activity and biomass when compared to darunavir alone (P<0.05). Conclusion. Darunavir presents antifungal activity against planktonic cells of Cryptococcus species and synergism with amphotericin B. In addition, darunavir led to reduced biofilm formation and showed activity against mature biofilms of Cryptococcus species. Activity of the antifungals against mature biofilms was enhanced in the presence of darunavir.


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