title: Antibacterial activity and QSAR of chalcones against biofilm-producing bacteria isolated from marine waters.
abstract: Biofouling in the marine environment is a major problem. In this study, three marine organisms, namely Bacillus flexus (LD1), Pseudomonas fluorescens (MD3) and Vibrio natriegens (MD6), were isolated from biofilms formed on polymer and metal surfaces immersed in ocean water. Phylogenetic analysis of these three organisms indicated that they were good model systems for studying marine biofouling. The in vitro antifouling activity of 47 synthesized chalcone derivatives was investigated by estimating the minimum inhibitory concentration against these organisms using a twofold dilution technique. Compounds C-5, C-16, C-24, C-33, C-34 and C-37 were found to be the most active. In the majority of the cases it was found that these active compounds had hydroxyl substitutions. A quantitative structure-activity relationship (QSAR) was developed after dividing the total data into training and test sets. The statistical measures r(2), [image omitted] (>0.6) q(2) (>0.5) and the F-ratio were found to be satisfactory. Spatial, structural and electronic descriptors were found to be predominantly affecting the antibiofouling activity of these compounds. Among the spatial descriptors, Jurs descriptors showed their contribution in all the three antibacterial QSARs.
authors.affiliation: Department of Biotechnology, Indian Institute of Technology-Madras, India.
authors.forename: P M
authors.initials: PM
authors.lastname: Sivakumar
authors.forename: V
authors.initials: V
authors.lastname: Prabhawathi
authors.forename: M
authors.initials: M
authors.lastname: Doble
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D001407:Bacillus / Q000187:drug effects / Q000302:isolation & purification; D001419:Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D018441:Biofilms / Q000187:drug effects*; D047188:Chalcones / Q000737:chemistry* / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D015233:Models, Statistical; D011108:Polymers / Q000378:metabolism; D011551:Pseudomonas fluorescens / Q000187:drug effects / Q000302:isolation & purification; D021281:Quantitative Structure-Activity Relationship; D012623:Seawater / Q000382:microbiology*; D014733:Vibrio / Q000187:drug effects / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D047188:Chalcones; D011108:Polymers