Characterization and antibiofilm activity of lipid nanovesicles containing essential oil of Thymus vulgaris

PEREZ, ANA PAULA; PEREZ, NOELIA; LOZANO, CARLOS MAURICIO SULIGOY; ALTUBE, MARIA JULIA; MARCELO ALEXANDRE DE FARIAS; RODRIGO VILLARES PORTUGAL; FERNANDA BUZZOLA; MARÍA JOSE MORILLA; EDER LILIA ROMERO

Mar del Plata

Congreso; Reunión Conjunta SAIC SAI SAFIS 2018; 2018

The clinical relevance of biofilms (matrix-enclosed communities ofbacteria that are adherent to surfaces) is related to their wide occurrencetogether with their ability to cause relapsing infections characterizedby chronic inflammation, tissue damage and the significantdifficulties in their eradication. The antibiotic tolerance shown bybacteria in the biofilm has been attributed mainly to the matrix, thatrestricts the access of antibiotics by binding them to their componentsor inactivating them by enzymes. In that way, lipid nanovesiclescontaining antimicrobial agents (AMA) could penetrate thebiofilm matrix and remain there releasing AMA in high doses.We have recently shown that the presence of total polar archaeolipidsof Halorubrum tebequichense (TPA) in lipid nanovesiclesincreased their chemical and colloidal stability. We hypothesizedthat the encapsulation of essential oil of Thymus vulgaris (AETv - apotent AMA that has low solubility in water and rapid decomposition)in archaeolipid nanovesicles would allow to obtain a stable aqueoussuspension of AETv with efficient antibacterial and antibiofilmactivity.Archaeolipid nanovesicles (soy phosphatidylcholine: TPA: Tween 801:1:1.6 w:w) of 129 ± 23 nm, Z potential -7 ± 1.5 mV and nanosphericalstructure, containing 41.6 ± 14.6 mg/ml of AETv (Arc-AETv) wereobtained by the lipid film hydration method. The encapsulation ofAETv in Arc-AETv increased the solubility of AETv 20.8 times withregards to an aqueous suspension. After 150 days of storage, Arc-AETv maintained the concentration of AETv and was stable colcolloidally.Finally, Arc-AETv presented antibacterial activity on bothplanktonic S. aureus and biofilm at lower concentrations than Tween80 1% v/v suspension of AETv and AETv in lipid nanovesicles lackingTPA (Lipo-AETv).In conclusion, the incorporation of AETv in archeolipid nanovesiclesfavored obtaining a stable formulation with effective antibiofilm activity.