Antibacterial activity of sesquiterpenes from Azorella cryptantha from San Juan, Argentina

LIMA, B.; SÁNCHEZ, M.; AGÜERO, M.B.; TAPIA, A.; PALERMO, J.A.; FERESIN, G.E.

Congreso; XXX Reunión Anual de la Sociedad de Biología de Cuyo; 2012

Azorella cryptantha(Clos) Reiche, Apiaceae), n.v. "yerba del soldado", is used in traditional medicine of San Juan (Argentina) to treat problems caused for food-borne illnesses associated with enterobacterium (digestive troubles). Herein we report the antibacterial properties of A. cryptantha according to CLSI methods. The extracts and fractions showed strong antimicrobial activity, against Escherichia coli ATCC 25922, Escherichia coli-LM1, Escherichia coli-LM2, Salmonella enteritidis-MI, with MICs values between 31.2 and 125 μg/ml. Diarrhoea caused by Escherichia coli infection is an emergent problem in both the developing and developed world, and is responsible for high rates of mortality in newborns. The bioassay-guided fractionation of the extracts led to the isolation for the first time of the sesquiterpenes chrysothol, stachytriol, 1b,10a,4b,5a-diepoxi-7b-germacran-6b-ol, and mulinol, (MICs=50 μg/ml) as the compounds responsible for antimicrobial activity, supporting the traditional use of A. cryptantha to treat digestive disorders.