A Review of Natural Products with Anti-biofilm Activity

Background: Biofilm is a microbial community of microbes that attach to a surface and are enclosed in an extracellular polymeric substance (EPS). Formation of these sessile communities and their inherent resistance to antimicrobial agents are the main reasons for many persistent and chronic infections. Chemotherapy of these infections is unsatisfactory for various reasons including unacceptable toxicity, poor efficacy and drug resistance. In this connection, the last few decades have witnessed wide investigations, which have been geared to investigate the anti-biofilm effects of natural products, including medicinal plant extracts and phytochemicals. Objective: This paper gives a review on the plant extracts and phytochemicals with antibiofilm capability, which hopefully provides useful information and guidance for future antimicrobial study. Method: This review is to summarize the natural products, including various phytochemicals, decoctions, plant fractions and extracts that have shown anti-biofilm activity. Literatures were collected from published articles that reported in vitro or in vivo anti-biofilm activity of natural products. Results: A total of 95 related references were found. The phytochemicals, fractions and extracts are grouped by their general classes or by their putative active components. More than 90 bioactive anti-biofilm compounds have been identified from different parts of the plants. The inhibitory concentration of the natural products was also included, and some of them were investigated for their possible anti-biofilm mechanism. Conclusion: This review has demonstrated solid evidences that plants are an excellent source to provide abundant natural compounds for the development of preventative and therapeutic agents against biofilm-based infections.