Antifungal and anti-inflammatory potential of the endangered aromatic plant Thymus albicans

Abstract

Thymus albicans is an endemic species of the Iberian Peninsula with a vulnerable conservation status. In an attempt to contribute to the valorization of this species, the present study brings new insights on the antifungal and anti-inflammatory mechanism of action of T. albicans essential oil. The antifungal activity of the oil and its major compounds was assessed for the first time against standard and clinically isolated strains of yeasts and filamentous fungi. The effect on the two major virulence factors of Candida albicans (germ tube formation and biofilm disruption) was considered in more detail. At 0.08 μL/mL, the oil inhibited C. albicans germ tube formation by more than 40% and decreased biofilm biomass at MIC values, thus pointing out its antivirulent potential. The anti-inflammatory activity of the essential oil was investigated on LPS-stimulated mouse macrophages (RAW 264.7) by evaluating the levels of several pro-inflammatory mediators, namely nitric oxide (NO), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). T. albicans oil reduced the production of nitrites, a NO derived sub-product, at non-cytotoxic concentrations of 0.32 and 0.64 μL/mL, by 27 and 41%, respectively. In addition, the iNOS protein levels of essential oil pre-treated cells were reduced by 14%. Overall, the high essential oil yield of T. albicans as well as its bioactive effects at concentrations without cytotoxicity, encourage further studies on the potential pharmacological applications of this species. Furthermore, these results raise awareness for the need to preserve endangered species that may hold relevant medicinal value.

Phytochemical Composition and Antioxidant, Anti-Acetylcholinesterase, and Anti-α-Glucosidase Activity of Thymus carnosus Extracts: A Three-Year Study on the Impact of Annual Variation and Geographic Location

“…In the same way as reported for other Thymus species listed in IUCN’s Red List, such as Thymus albicans (Hoffmanns. and Link), which is listed as vulnerable [ 11 , 12 ], a large number of these species are only now beginning to be characterized regarding their phytochemical composition, bioactivities, and potential use for human health benefit. Through the study of its health-promoting effects, it is expected to raise awareness towards a sustainable crop aiming at later industrial applications, as well as the maintenance of biodiversity.…”

Molecular Characterization of Thymus capitellatus Extracts and Their Antioxidant, Neuroprotective and Anti-Proliferative Activities

“…Roxo et al (2020) [ 6 ] provided a scientific background to the traditional use of T. albicans to treat inflammation as well as its potential use as an antifungal agent. The essential oil of T. albicans exerts anti-inflammatory activity at non-cytotoxic concentrations by inhibiting the activity of inducible nitric oxide synthase (iNOS), and consequently reducing nitric oxide (NO) levels, as well as antifungal activity against various Candida , Microsporum , Trichophyton or Aspergillus strains, highlighting its potential applications in pharmaceutical industry.…”

Antifungal and genotoxic effects of Thymus serpyllum as a root canal irrigant

“…Fani and Kohanteb ( 2017 ) reported that Thymus vulgaris was effective against C. albicans isolated from patients with denture stomatitis and infected root canal in a zone of inhibition of 7.5‐42.00 mm in agar plates with Thymus vulgaris oil with a concentration between 156 and 256 µg/mL. Furthermore, Roxo et al ( 2020 ) showed that this thymus oil was able to inhibit germ tube formation and biofilm integrity in C. albicans . Finally, Oliveira et al ( 2017 ) demonstrated that T. vulgaris L. extract exhibited effective biological activities and could control monomicrobial biofilms of C. albicans when used at 200 mg/mL.…”