The essential oil of Melaleuca alternifolia incorporated into hydrogel induces antimicrobial and anti-inflammatory effects on infected wounds by Staphylococcus aureus

• Published in: Biomedicine & pharmacotherapy Vol. 173; p. 116389
• Main Authors: Vila Nova, Beatriz Gomes, Silva, Lucas dos Santos, Andrade, Marcos da Silva, de Santana, Amanda Vitória Sevidanes, da Silva, Leticia Cely Tavares, Sá, Gabrielle Chaves, Zafred, Ivana Fiquene, Moreira, Pedro Henrique de Aguiar, Monteiro, Cristina Andrade, da Silva, Luís Cláudio Nascimento, Abreu, Afonso Gomes
• Format: Journal Article
• Language: English
• Published: France Elsevier Masson SAS 01.04.2024; Elsevier
• Subjects: Anti-inflammatory; Antibacterial; Essential oil; Healing; Hydrogel; Melaleuca; Melaleuca; Healing; Essential oil; Hydrogel; Antibacterial; Anti-inflammatory
• ISSN: 0753-3322; 1950-6007
• DOI: 10.1016/j.biopha.2024.116389

Staphylococcus aureus is one of the most common bacterial isolates found in wounds. Thus, innovative dressings, such as hydrogels, are interesting vehicles for incorporating bioactive compounds like those from Melaleuca alternifolia essential oil (MaEO). In this study, we evaluated the antimicrobial and anti-inflammatory potential of MaEO incorporated into an alginate and chitosan hydrogel for treating wounds infected by S. aureus. The hydrogel incorporated with MaEO 1% (HMa 1%) was homogeneous with a bright pale-yellow color and the characteristic smell of Melaleuca. The incorporation of MaEO 1% does not affect the stability of the hydrogel, which was stable up to 90 days of storage. The Scanning electron microscopy analysis revealed that hydrogels showed irregular surfaces and interconnected porous structures with accumulations of oil crystals distributed throughout the formulation. HMa 1% has a high moisture content (95.1%) and can absorb simulated wound fluid. Regarding the antimicrobial effects, HMa 1% reduced the growth of S. aureus ATCC 6538 in both in vitro conditions and in an ex vivo model of wounds using porcine skin. In addition, the dairy topical treatment of murine skin lesions with HMa 1% induced a significant reduction of the wound area, inflammation score, and bacterial load, as well as tissue re-epithelialization and modulation of inflammatory mediators. Therefore, hydrogel incorporated with MaEO 1% has excellent potential to be used in the pharmacotherapy of infected wounds. [Display omitted] •Essential oil of M. alternifolia inhibits S. aureus in vitro, in vivo and ex vivo.•Hydrogel of Melaleuca reduces the severity of S. aureus-infected wounds.•Treatment with HMa 1% improves re-epithelialization of infected wounds.•Hydrogel of Melaleuca inhibits the production of nitric oxide in mice.•Treatment with HMa 1% stimulates the production of IL-10 in mice.