# Antibiofilm Activity of Combretum micranthum G. Don Catechin–Sugar Phytocomplex on Pseudomonas aeruginosa

## TL;DR

A plant extract from Combretum micranthum shows strong antibiofilm activity against Pseudomonas aeruginosa, a bacteria known for causing chronic infections.

## Contribution

The study identifies a phytocomplex in Combretum micranthum with significant antibiofilm properties against Pseudomonas aeruginosa.

## Key findings

- Cm4-p inhibited biofilm formation in both PAO1 and B13 strains of Pseudomonas aeruginosa.
- The extract is mainly composed of catechins with sugar moieties, as shown by IR, UV-vis, NMR, and mass spectrometry analyses.

## Abstract

Clinicians often have to face infections caused by microorganisms that are difficult to eradicate due to their resistance and/or tolerance to antimicrobials. Among these pathogens, Pseudomonas aeruginosa causes chronic infections due to its ability to form biofilms on medical devices, skin wounds, ulcers and the lungs of patients with Cystic Fibrosis. In this scenario, the plant world represents an important reservoir of natural compounds with antimicrobial and/or antibiofilm properties. In this study, an extract from the leaves of Combretum micranthum G. Don, named Cm4-p, which was previously investigated for its antimicrobial activities, was assayed for its capacity to inhibit biofilm formation and/or to eradicate formed biofilms. The model strain P. aeruginosa PAO1 and its isogenic biofilm hyperproducer derivative B13 were treated with Cm4-p. Preliminary IR, UV-vis, NMR, and mass spectrometry analyses showed that the extract was mainly composed of catechins bearing different sugar moieties. The phytocomplex (3 g/L) inhibited the biofilm formation of both the PAO1 and B13 strains in a significant manner. In light of the obtained results, Cm4-p deserves deeper investigations of its potential in the antimicrobial field.