Antimicrobial activity of Limonium avei (De Not.) Brullo & Erben extracts
Limonium avei (De Not.) Brullo & Erben (Plumbaginaceae) is a rare triploid (2n=27), annual halophyte, with apomictic reproduction , included in the Red List of Endangered Species by the IUCN . The species is endemic to the central Mediterranean coast and in Liguria (Italy) it is present in only one population, with almost 1500 individuals. The increasing urbanization of the Ligurian population natural habitat has prompted the adoption of measures for its conservation. As part of this effort ex situ seed conservation and tissue culture techniques were developed for the species . To the best of our knowledge, no study reporting to biological activity is present in literature. Here we reported for the first time the antimicrobial activity and phytochemical profile of Limonium avei ethanol and dichloromethane extracts. Flowering stems collected in the natural site were compared with flowering stems collected in the CRA-FSO greenhouse from micropropagated acclimatised plants. Tissues were air dry at room temperature for 60 days. The antimicrobial activity of extracts was performed by the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC)  against Gram-positive, Gram-negative bacteria and mycetes. The extracts were submitted to phytochemical screening by LCMS and HPLC/DAD analyses. The results indicated that the ethanol extracts of both samples displayed higher activity than dichloromethane extracts and this activity was more pronounced against Gram-positive than Gram-negative bacteria and mycetes. In particular, the extracts demonstrated MIC and MBC values ranging from 15.6 to 500µg/ml and from 500 to 4000µg/ml respectively.
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