Mebarki Ali, Université de Montpellier, UMR Qualisud, Doctorant, France,
Guzman Caroline, Université de Montpellier, UMR Qualisud , Technicien, France,
Portet Karine, Université de Montpellier, UMR Qualisud , Technicien, France,
Morel Sylvie, Université de Montpellier, CEFE, Maitre de conférences, France,
Michel Alain, Université de Montpellier, Qualisud, Professeur, France,
Poucheret Patrick, Université de Montpellier, Qualisud, Maitre de conférences,
Boudard Frédéric, Université de Montpellier, Qualisud, Maitre de conférences, France,
Introduction and purpose of the study
Lippia multiflora is a plant from the Verbenaceae family. It is an aromatic, woody, angular and pubescent herb, branched with inflorescences. Lippia has recently been identified as an African plant with high commercial potential due to its anti-hypertension properties The present study based on in-vitro tests explores the anti-inflammatory activity of 2 leaf extracts (citral and thymol) of Lippia multiflora by the quantification of nitric oxide (NO) and tumor necrosis factor ? (TNF ? ) produced by activated J774.A1 cells (murine macrophage cell line).
Materials and methods
A batch of Lippia leaves was crushed, sieved and then subjected to hydroethanolic maceration. Cell viability was evaluated in order to validate the absence of cytotoxicity of the extracts on J774A.1 cells. The inflammatory activities linked to the analgesic component, the impacts on tumor necrosis factor-alpha (TNF-?) and nitric oxide (NO) have been determined.
Results and discussion
The cell viability test (MTS / PMS) was performed to assess the cytoxicity of Lippia extracts. After exposure of the cells to the extracts, we observed absorbances identical to those of the untreated cell control indicating an absence of cytotoxicity.
The anti-inflammatory capacity of lippia multiflora extracts was assessed using the nitric oxide test after exposure to increasing concentrations of extracts. The results indicate that citral inhibits the production of NO in a concentration-dependent manner. This inhibition reaches the maximum value of 89.72%. As for thymol, we observe a decrease in NO production, this effect is less marked and is important only at high concentrations with a maximum inhibition of 52.47%. The two extracts showed an inhibitory effect on the production of TNF ? by J774.A1 cells in a concentration-dependent manner. This inhibition reaches the maximum value around 71% at the concentration 1/800 for both, citral and thymol.