Antimicrobial photodynamic therapy with Ligularia fischeri against methicillin-resistant Staphylococcus aureus infection in Caenorhabditis elegans model

Abstract

The high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) infection threatens the effectiveness of current clinical settings. Antimicrobial photodynamic therapy (APDT) is a promising alternative to antibiotics for treating infections due to its low resistance. This study aimed to evaluate the antibacterial properties of APDT with L. fischeri extract (LFE) against MRSA and various skin and oral pathogens in vitro and its photopharmaceutical actions in Caenorhabditis elegans. The antimicrobial activities of APDT with LFE against pathogens were evaluated using plate counting method. The chemical profile was characterized using high-performance liquid chromatography and spectrophotometry. The growth rate assay, lifespan assay, and bacterial attachment on worms were performed to assess the therapeutics effects in C. elegans. The swab method was used for the detection of pathogens on the micropig skin surface. The APDT treatment with L. fischeri extract (LFE, 20 µg/mL) and red light (intensity of 120 W/m2) reduced 4.3–4.9 log (colony forming unit/mL) of Staphylococcus aureus, MRSA, Cutibacterium acnes, Streptococcus mutans; and 2.4 log (CFU/mL) of Candida albicans. Chemical analysis revealed that LFE enriched three active photosensitizers. APDT reduced bacterial populations on worms, recovered growth retardation, and improved lifespan in MRSA-infected C. elegans without causing severe side effects. The surface eradication of MRSA after exposure to LFE with red light was demonstrated on micropig skin. These findings highlight the significance of L. fischeri as a natural resource for the safe phototreatment of MRSA infection in the biomedical and cosmeceutical industries.

Synergistic bactericidal effects of carvone and β-lactams against Xanthomonas campestris pv. vesicatoria

“…Their use as antibacterial activity against Bacillus, Staphylococcus, Pseudomonas, and Salmonella has also been reported [22,23]. They can donate and accept electrons because of their structural characteristics along with their potential to function as inducers of reactive oxygen species (ROS) [24], and can destroy the cell membrane and penetrate the cytoplasm of bacteria, resulting in ROS [25], because intracellular ROS exerts a bactericidal effect through its involvement in DNA damage, lipid peroxidation, protein denaturation, and enzyme inactivation [26][27][28].…”

Morphological changes and viability of Streptococcus mutans biofilm treated with erythrosine: A confocal laser scanning microscopy analysis

“…Photodynamic antimicrobial therapy (a‐PDT) is a modality that employs the combination of visible light, a drug (known as photosensitizer – PS or dye) and molecular oxygen, which serves as an alternative approach to antimicrobial agents aiming inactivation of microorganisms, especially those organized in biofilms. The combination of all components of a‐PDT is necessary for the production of reactive oxygen species (ROS), which are capable of reacting with intra‐ and extracellular structures causing irreversible damage and bacterial death (Costa et al, 2012; Ha et al, 2023; Mahdi et al, 2015; Mesquita et al, 2018; Soares et al, 2023; Vendramini et al, 2020).…”

Antimicrobial Photodynamic Therapy (Apdt), An Approach To Fightback Against Antibiotic Resistance: A Short Review

“…This resistance is spreading among nosocomial pathogens known as ESKAPE that includes Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp. (1)(2)(3)(4)(5)(6)(7). This deliver a message that sooner we will face a huge drug resistance problem by 2050 and the estimated death rate will be 10 million per year (1,2).…”