The inhibitory effects of mushroom extracts on sucrose-dependent oral biofilm formation

Dental plaque is a multispecies oral biofilm, the development of which is initiated by adherence of the pioneerStreptococcusspp. OralVeillonellaspp., includingV. atypica,V. denticariosi,V. dispar,V. parvula,V. rogosae, andV. tobetsuensis, are known as early colonizers in oral biofilm formation. These species have been reported to coaggregate withStreptococcusspp. in a metabolic cooperation-dependent manner to form biofilms in human oral cavities, especially in the early stages of biofilm formation. However, in our previous study,Streptococcus gordoniishowed biofilm formation to the greatest extent in the presence ofV. tobetsuensis, without coaggregation between species. These results suggest thatV. tobetsuensisproduces signaling molecules that promote the proliferation ofS. gordoniiin biofilm formation. It is well known in many bacterial species that the quorum-sensing (QS) system regulates diverse functions such as biofilm formation. However, little is known about the QS system with autoinducers (AIs) with respect toVeillonella and Streptococcusspp. Recently, autoinducer 1 (AI-1) and AI-2 were detected and identified in the culture supernatants ofV. tobetsuensisas strong signaling molecules in biofilm formation withS. gordonii. In particular, the supernatant fromV. tobetsuensisshowed the highest AI-2 activity among 6 oralVeillonellaspecies, indicating that AIs, mainly AI-2, produced byV. tobetsuensismay be important factors and may facilitate biofilm formation ofS. gordonii. Clarifying the mechanism that underlies the QS system betweenS. gordoniiandV. tobetsuensismay lead to the development of novel methods for the prevention of oral infectious diseases caused by oral biofilms.

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Candida albicans Biofilm Inhibition by Two Vaccinium macrocarpon (Cranberry) Urinary Metabolites: 5-(3′,4′-DihydroxyPhenyl)-γ-Valerolactone and 4-Hydroxybenzoic Acid

Microorganisms ◽

10.3390/microorganisms9071492 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1492

Author(s):

Emerenziana Ottaviano ◽

Giovanna Baron ◽

Laura Fumagalli ◽

Jessica Leite ◽

Elisa Adele Colombo ◽

...

Keyword(s):

Biofilm Formation ◽

Urinary Metabolites ◽

Hydroxybenzoic Acid ◽

Inhibitory Effects ◽

Candida Spp ◽

Biofilm Inhibition ◽

Strain Sc5314 ◽

Candida Infections ◽

Dose Dependent

Candida spp. are pathobionts, as they can switch from commensals to pathogens, responsible for a variety of pathological processes. Adhesion to surfaces, morphological switch and biofilm-forming ability are the recognized virulence factors promoting yeast virulence. Sessile lifestyle also favors fungal persistence and antifungal tolerance. In this study, we investigated, in vitro, the efficacy of two urinary cranberry metabolites, 5-(3′,4′-dihydroxy phenyl)-γ-valerolactone (VAL) and 4-hydroxybenzoic acid (4-HBA), in inhibiting C. albicans adhesion and biofilm formation. Both the reference strain SC5314 and clinical isolates were used. We evaluated biomass reduction, by confocal microscopy and crystal violet assay, and the possible mechanisms mediating their inhibitory effects. Both VAL and 4-HBA were able to interfere with the yeast adhesion, by modulating the expression of key genes, HWP1 and ALS3. A significant dose-dependent reduction in biofilm biomass and metabolic activity was also recorded. Our data showed that the two cranberry metabolites VAL and 4-HBA could pave the way for drug development, for targeting the very early phases of biofilm formation and for preventing genitourinary Candida infections.

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Inhibition of Biofilm Formation in Bacteria by Essential Oils: تثبيط تكون البيوفيلم في البكتيريا بواسطة الزيوت العطرية

Journal of medical and pharmaceutical sciences - مجلة العلوم الطبية و الصيدلانية ◽

10.26389/ajsrp.l091220 ◽

2020 ◽

Vol 4 (4) ◽

Author(s):

Mashaeal Saud Alshilawi, Howard Foster

Keyword(s):

Essential Oils ◽

Biofilm Formation ◽

Research Question ◽

In Vitro Test ◽

Test Results ◽

Inhibitory Effects ◽

Anova Analysis ◽

Black Seed ◽

Vitro Test

The formation of S. epidermidis and P. aeruginosa biofilms were successfully inhibited in the presence of sub-inhibitory concentrations of S. aromaticum (clove) and L. angustifolia (lavender) essential oils. These substances achieved good in-vitro test results. On the other hand, pure and organic types of N. sativa (black seed) essential oil did not exhibit any inhibitory effects on the biofilm formed by the tested bacteria. Although the tested essential oils may share a similar mechanism of action, ANOVA analysis showed strong statistical differences between all essential oils at their sub-MIC levels, and also identified two different trends, biofilm inhibitors, represented by S. aromaticum (clove) and L. angustifolia (lavender) oils, and biofilm stimulators, represented by both types of N. sativa (black seed) oils. A more thorough perspective on the research question could be achieved by considering the various elements that have essentially contributed to the processes and the findings within this study.

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Understanding Lactobacillus paracasei and Streptococcus oralis Biofilm Interactions through Agent-Based Modeling

mSphere ◽

10.1128/msphere.00875-21 ◽

2021 ◽

Author(s):

Linda Archambault ◽

Sherli Koshy-Chenthittayil ◽

Angela Thompson ◽

Anna Dongari-Bagtzoglou ◽

Reinhard Laubenbacher ◽

...

Keyword(s):

Biofilm Formation ◽

Oral Candidiasis ◽

Agent Based Modeling ◽

Cell Models ◽

Complex Environments ◽

Inhibitory Effects ◽

Content Type ◽

Agent Based ◽

Streptococcus Oralis

We previously discovered a role of the oral commensal Streptococcus oralis as an accessory pathogen. S. oralis increases the virulence of Candida albicans infections in murine oral candidiasis and epithelial cell models through mechanisms which promote the formation of tissue-damaging biofilms. Lactobacillus species have known inhibitory effects on biofilm formation of many microbes, including Streptococcus species. Agent-based modeling has great advantages as a means of exploring multifaceted relationships between organisms in complex environments such as biofilms.

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