title: Antimicrobial activity of saponins from Medicago sp.: structure-activity relationship.
abstract: The antimicrobial activity of saponins from Medicago sativa, M. arborea and M. arabica against a selection of medically important yeasts, Gram-positive and -negative bacteria was investigated. Structure-activity growth inhibitory effects of related prosapogenins and sapogenins are also described. Increasing antibiotic activity was observed going from the saponin extracts to the sapogenin samples, suggesting that the sugar moiety is not important for the antimicrobial efficacy. Activity was especially high against Gram-positive bacteria (Bacillus cereus, B. subtilis, Staphylococcus aureus and Enterococcus faecalis) with M. arabica being the species showing a broader spectrum of action. Discrete antifungal activity was also observed, mainly against Saccharomyces cerevisiae. The observed antimicrobial properties of M. sativa and M. arborea were related to the content of medicagenic acid, while hederagenin seems to contribute to the bioactivity of M. arabica total sapogenins.
authors.affiliation: Dipartimento Farmaco-Chimico, Via Orabona 4, Università, I-70125 Bari, Italy. avato@farmchim.uniba.it
authors.forename: Pinarosa
authors.initials: P
authors.lastname: Avato
authors.forename: Rossella
authors.initials: R
authors.lastname: Bucci
authors.forename: Aldo
authors.initials: A
authors.lastname: Tava
authors.forename: Cesare
authors.initials: C
authors.lastname: Vitali
authors.forename: Antonio
authors.initials: A
authors.lastname: Rosato
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Bialy
authors.forename: Marian
authors.initials: M
authors.lastname: Jurzysta
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis / Q000494:pharmacology*; D000935:Antifungal Agents / Q000032:analysis / Q000494:pharmacology*; D020128:Inhibitory Concentration 50; D029902:Medicago / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D012502:Sapogenins / Q000302:isolation & purification; D012503:Saponins / Q000032:analysis / Q000494:pharmacology*; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D012502:Sapogenins; D012503:Saponins