Developing natural products as potential anti-biofilm agents

Abstract

Biofilm is a natural form of bacterial growth ubiquitously in environmental niches. The biofilm formation results in increased resistance to negative environmental influences including resistance to antibiotics and antimicrobial agents. Quorum sensing (QS) is cell-to-cell communication mechanism, which plays an important role in biofilm development and balances the environment when the bacteria density becomes high. Due to the prominent points of biofilms implicated in infectious disease and the spread of multi-drug resistance, it is urgent to discover new antibacterial agents that can regulate biofilm formation and development. Accumulated evidences demonstrated that natural products from plants had antimicrobial and chemo-preventive properties in modulation of biofilm formation in the last two decades. This review will summarize recent studies on the discovery of natural anti-biofilm agents from plants with clear-cut mechanisms or identified molecular addresses, as well as some herbs with unknown mechanisms or unidentified bioactive ingredients. We also focus on the progression of techniques on the extraction and identification of natural anti-biofilm substances. Besides, anti-biofilm therapeutics undergoing clinical trials are discussed. These newly discovered natural anti-biofilm agents are promising candidates which could provide novel strategies for biofilm-associated infections.

Antimicrobial and Antioxidant Properties of Four Lycopus Taxa and an Interaction Study of Their Major Compounds

“…These substances may act through different mechanisms than conventional antibiotics, and thus they can be utilized in the treatment of infections caused by resistant bacteria. These mechanisms include inhibition of synthesis of nucleic acids, direct interaction with the cell membrane structures of bacteria, which lead to their damage, inhibitory effects on electron transport in the bacterial respiratory chain, and quorum sensing inhibition [25,26]. Several studies on the antimicrobial activity of L. europaeus extracts or isolated compounds of several microbial species have been published in the past.…”

Demolishing the great wall of biofilms in Gram‐negative bacteria: To disrupt or disperse?

“…With rapid advances in compound discovery, it is imperative to identify novel anti‐biofilm compounds that can disrupt or disperse biofilms. Natural compounds from plants are excellent sources of potential anti‐biofilm compounds, where many QSIs are previously identified, while the recently‐discovered pyocins and norspermidine displayed promising potential against biofilms …”

Highly Efficient Antibiofilm and Antifungal Activity of Green Propolis againstCandidaspecies in dentistry material

“…A combination of factors contribute to Candida sp biofilm formation, salivary flow, low pH, poor oral hygiene and the type of orthodontic material contribute to biofilm colonization and formation (2). During colonization and biofilm formation, oral microbiota secrete enzymes and exopolysaccharides to colonize a surface, thus the biofilm constitutes as a film of organic components that are absorbed from saliva forming an extracellular polymeric matrix and thus the multicellular community (bacteria or fungus) is incorporated into the extracellular matrix (ECM) (1–3).…”

“…The formation of biofilm in orthodontic materials raises concern as, when installed, increases the risk of infection, antibiotic and antifungal resistance, becoming an infectious site and obstacle for therapies. Natural products may inhibit biofilm formation, however, antibiofilm effects depends on inhibition of extracellular matrix formation, adhesin inhibition and cell attachment and inhibition of virulence factors (3).…”