Chemical composition and evaluation of the antimicrobial activity of Valeriana prionophylla Standl. from Guatemala

Valeriana prionophylla Standl. (Caprifoliaceae) is a perennial herb native of Guatemala and found usually over 2100 m at the western highlands of the country. The plant is traditionally used in Guatemala as antipyretic, anticonvulsive, spasmolytic, tranquilizer, sedative, among other uses. Root and rhizome samples of V. prionophylla were collected in July 2014 in populations at San José Ojetenam in the the western province of San Marcos at an altitude of 3350 m. The essential oil was obtained by hydrodistillation for two hours (average yield: 1.55% w/w). The oil components were identified by GC/MS through their mass spectra and retention indices and quantified based on their GC/FID peak areas, showing isovaleric acid, bornyl acetate and valerenic acid as main components (up to 60%). The inhibitory activity of the essential oil against two Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus), two Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli) and one yeast strain (Candida albicans) was evaluated by the agar diffusion method (Kirby-Bauer method). The oil presented activity against all the tested organisms with inhibition halos of 25 mm (S. aureus) 29 mm (B. cereus), 21 mm (P. aeruginosa), 19 mm (E. coli) and 13 mm (C. albicans). The results suggest that the essential oil of V. prionophylla could be used as potential antimicrobial in the development of products in medicine and in the food industry.

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