Antifungal activities and chemical composition of the essential oil of Lippia micromera (Verbenaceae) cultivated in French Guiana

French Guyana is a part of the Amazonia rainforest identified as a biodiversity hotspot for both animal and plant species threatened with extinction [1]. With the generalized awareness of this endangered richness a number of conservation and promotion actions have been undertaken over the last years. In collaboration with the Guyarômes society, the potential valorization of essential oils from local plants on the international market is assessed. Lippia micromera Schauer (Verbenaceae family) is a strong aromatic shrub with many branched and white tiny flowers with yellow throat. Its origin is not well established but it is assumed that the plant is from northern South America (Colombia, Venezuela and Guiana), the Caribbean and Nicaragua. [2] It is one of the selected plants for such a valorization action. The species is well known for culinary seasoning, anti-inflamatory, anti-microbial and antioxidant activities [3]. The present poster reports for the first time the analysis of the chemical composition by GC-FID and GC-MS of the essential oil of L. micromera organically cultivated in French Guiana. A total of thirty-one components accounting for 97% of the total GC-FID chromatogram were identified. The evaluation of its antimicrobial and antiparasitic activities against strains of several Candida spp. (MIC) and Leishmania guyanensis (IC₅₀) respectively shows a strong antimicrobial activity ranging from 125 µg/ml to 500 µg/ml according to the Candida species tested, while the anti-leishmania activity seems negligible. Thus the EO was assessed for its anti-ageing and antioxidant properties (in vitro tests in 96-wells plates) and revealed also a strong percentage of inhibition (more than 60%) for elastase and lipoxygenase assays.

Acknowledgements: The authors are grateful to Guyarômes for the financial support they provided and for making the essential oil samples available.

Keywords: Lippia micromera, Verbenaceae, French Guiana, antifungal and antiparasitic activities, Candida spp, Leishmania guyanensis.

References:

[1] Myers N, Mittermeier RA, Mittermeier CG, da Fonseca GAB, Ken J. Biodiversity hotspots for conservation priorities. Nature 2000; 403: 853 – 858

[2] Staples GW, Kristiansen MS, Lippia micromera Schauer Verbenaceae, the verbena family In: Ethnic culinary herbs: A guide to identification and cultivation in Hawaii. Edits., University of Hawaii Press 1999; Honolulu: 56 – 57

[3] Zapata B, Betancur-Galvis L, Duran C, Stashenko E, Cytotoxic activity of Asteraceae and Verbenaceae family essential oils. J Essent Oil Res 2014; 26: 50 – 57