Smida I. auteur aut IRD Charpy Claude auteur aut IRD Cherif S. Y. auteur aut IRD Torre F. auteur aut IRD Audran G. auteur aut IRD Smiti S. auteur aut IRD Le Petit J. auteur aut IRD text journalArticle eng text/pdf born digital access Ludwigia peploides subsp. montevidensis and Ludwigia grandiflora subsp. hexapetala, form aquatic dense stands, which cause major ecological and economical problems in many aquatic ecosystems in France. However, these species are known to release allelopathic compounds. Here, antibacterial properties were assessed on samples from different plant organs, during June, July and August for L. peploides and throughout the development period, from April to September, for L. grandiflora. The disk diffusion method was used here to screen dimethylsulfoxide plant extracts against 5 Gram positive and 9 Gram negative bacterial strains. The sensitivity of the bacteria tested to L. grandiflora extracts was greater than that to those of L. peploides. Maximum antibacterial activity was measured in June, July or August, depending on the plant organ, principally in leaf and flower extracts. Activity also varied according to the bacterial strains tested. A principal component analysis (PCA) showed that sensitivity to the plant extracts did not depend' on whether the bacterial strains are Gram positive or Gram negative. Thus, we found that a Gram positive strain, Staphylococcus aureus (CIP 76.25), and a Gram negative strain, Salmonella enterica (DSM 10062), were similar in sensitivity. Antibacterial activities of certain leaf or flower extracts of both species of Ludwigia were revealed superior to those of several classic antibiotics tested. The interest of this study concerns the therapeutical potential of the two Ludwigia species. specialized Ludwigia peploides Ludwigia grandiflora Aquatic habitat Antibacterial properties FRANCE 034 035 121 39-45 2015 0304-3770 https://www.documentation.ird.fr/hor/fdi:010063731 10.1016/j.aquabot.2014.10.011 0304-3770 [F B010063731] https://www.documentation.ird.fr/hor/fdi:010063731 https://www.documentation.ird.fr/intranet/publi/2015/03/010063731.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2015-04-07 2017-08-23 fdi:010063731 fre