Pithecellobium clypeariaextract enriched in gallic acid and luteolin has antibacterial activity against MRSA and reduces resistance to erythromycin, ceftriaxone sodium and levofloxacin

Abstract

Aims Antibiotic adjuvants can give a second life to the antibiotics to which bacteria are highly resistant. We evaluated the antimicrobial effects of extracts from Pithecellobium clypearia against methicillin‐resistant Staphylococcus aureus (MRSA) and also the potential for synergy with several antibiotics. Methods and Results For this study, four extracts from P. clypearia were tested on MRSA using the broth microdilution method for activity assessment. The ethyl acetate fraction (S20b) had the strongest antibacterial activity against MRSA among the fractions tested. In all, 14 compounds such as gallic acid and luteolin in S20b were analysed by UFLC‐Q‐TOF‐MS/MS. S20b combined with erythromycin showed synergy effects against MRSA and combined with ceftriaxone sodium and levofloxacin showed additive effects against MRSA. Electron microscopy showed that extract S20b damaged the MRSA cell wall and K+ efflux measurements indicated that extract S20b increased cell membrane permeability. Moreover, S20b suppression of PBP2a expression was assessed by Western blot. Furthermore, an in vivo study was used to investigate the therapeutic potential of S20b based on a mouse pneumonia model. Conclusions The in vitro study results have shown that S20b not only inhibits MRSA growth directly but also reduces the resistance of MRSA to the evaluated antibacterial agents. Based on the in vivo study, it can be concluded that S20b can treat pneumonia in the mouse model. Significance and Impact of the Study This study is the first research to demonstrate that S20b can inhibit MRSA growth and reduce drug resistance of clinical isolates to antibiotics. S20b has the potential to be used as a therapeutic agent against MRSA and treatment for MRSA pneumonia.

Synergistic Antibacterial Activity with Conventional Antibiotics and Mechanism of Action of Shikonin against Methicillin-Resistant Staphylococcus aureus

“…A synergistic interaction between SKN and antibiotics against MRSA was investigated using the checkerboard method [ 30 ]. The MRSA cultures (ATCC33591, CCARM 3090 and DPS-1) were grown in the presence of SKN at concentrations of 1/32 × MIC, 1/16 × MIC, 1/8 × MIC, 1/4 × MIC and 1/2 × MIC in combination with OXA, GEN, AMI, AMO, CEFO, CEFT, and CHL, with each concentration range from 1/32 × MIC to 1/2 × MIC.…”

Novel Opportunity to Reverse Antibiotic Resistance: To Explore Traditional Chinese Medicine With Potential Activity Against Antibiotics-Resistance Bacteria

“…Ethyl acetate fraction from Pithecellobium clypearia was found to exhibit therapeutic potential for MRSA pneumonia in pneumonia mouse model. S20b damaged the MRSA cell wall and promoted more potassium ions to flow out of the cells to increase the permeability of cell membrane in vivo (Liu et al, 2020). In addition, Baicalein isolated from Scutellaria baicalensis, is found to attenuate the virulence of S. aureus and protects mice from S. aureus induced lethal pneumonia through blocking the coagulase activity of von Willebrand factor-binding protein in S. aureus (Zhang et al, 2020).…”

Luteolin Inhibits the Biofilm Formation and Cytotoxicity of Methicillin-Resistant Staphylococcus aureus via Decreasing Bacterial Toxin Synthesis

“…In related studies, mice are frequently used as animal experimental models with S. aureus infection, and MRSA has been uncovered to increase the ratio of MRSA colony count/lung weight in mouse pneumonia model [ 53 ]. Furthermore, the Pithecellobium clypearia extract enriched in luteolin and gallic acid has antibacterial activity against MRSA [ 53 ]. In the present study, luteolin was discovered to increase the MRSA-decreased mice survival rate.…”