Evaluation of the Antioxidant, Cytotoxicity, Antibacterial, Anti-Motility, and Anti-Biofilm Effects of <i>Myrothamnus flabellifolius</i> Welw. Leaves and Stem Defatted Subfractions

The formation of biofilms underscores the challenge of treating bacterial infections. The study aimed to assess the antioxidant, cytotoxicity, antibacterial, anti-motility, and anti-biofilm effects of defatted fractions from <i>Myrothamnus flabellifolius</i> (resurrection plant). Antioxi...

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Bibliographic Details
Main Authors: Mashilo Mash Matotoka, Peter Masoko
Format: Article
Language:English
Published: MDPI AG 2024-03-01
Series:Plants
Subjects:
Online Access:https://www.mdpi.com/2223-7747/13/6/847
Description
Summary:The formation of biofilms underscores the challenge of treating bacterial infections. The study aimed to assess the antioxidant, cytotoxicity, antibacterial, anti-motility, and anti-biofilm effects of defatted fractions from <i>Myrothamnus flabellifolius</i> (resurrection plant). Antioxidant activity was assessed using DPPH radical scavenging and hydrogen peroxide assays. Cytotoxicity was screened using a brine shrimp lethality assay. Antibacterial activity was determined using the micro-dilution and growth curve assays. Antibiofilm potential was screened using the crystal violet and tetrazolium reduction assay. Liquid–liquid extraction of crude extracts concentrated polyphenols in the ethyl acetate and n-butanol fractions. Subsequently, these fractions had notable antioxidant activity and demonstrated broad-spectrum antibacterial activity against selected Gram-negative and Gram-positive bacteria and <i>Mycobacterium smegmatis</i> (MIC values < 630 μg/mL). Growth curves showed that the bacteriostatic inhibition by the ethyl acetate fractions was through the extension of the lag phase and/or suppression of the growth rate. The sub-inhibitory concentrations of the ethyl acetate fractions inhibited the swarming motility of <i>Pseudomonas aeruginosa</i> and <i>Klebsiella pneumoniae</i> by 100% and eradicated more than 50% of <i>P. aeruginosa</i> biofilm biomass. The polyphenolic content of <i>M. flabellifolius</i> plays an important role in its antibacterial, anti-motility, and antibiofilm activity, thus offering an additional strategy to treat biofilm-associated infections.
ISSN:2223-7747