title: Facile green synthesis of baicalein fabricated gold nanoparticles and their antibiofilm activity against Pseudomonas aeruginosa PAO1.
abstract: Biofilm formation is one of the major problems associated with chronic diseases and also attributes for the antibiotic resistance in bacteria. In recent times nanoparticles have been utilized to improve the efficacy of the existing antimicrobial and anti-biofilm agents. The ease in functionalization of gold nanoparticles (AuNPs) makes them a potential carrier for antimicrobial agents. However, the use of physical or chemical methods of the production of nanoparticles is expensive, labour intensive and hazardous to ecosystem. On the other hand, the use of plant based compounds serve as an eco-friendly way for the synthesis of nanoparticles with improved biocompatibility and therapeutic applicability. In the present study, phytocompound, baicalein was used as a reducing and capping agent for the synthesis of spherical shape AuNPs. The baicalein decorated gold nanoparticles (BCL-AuNPs) were characterized and evaluated for their anti-biofilm efficacy against Pseudomonas aeruginosa PAO1. The biosynthesized BCL-AuNPs was characterized using UV-Visible spectra, Dynamic Light Scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Diffraction (EDAX), and High Resolution Transmission Electron Microscopy (HR-TEM). The biosynthesized BCL-AuNPs were determined to be spherical in shape with an average size of 26.5 nm. The sub-MIC concentration of BCL-AuNPs exhibited significant anti-biofilm activity against P. aeruginosa PAO1. On treatment with BCL-AuNPs (100 g mL-1), a reduction in biofilm formation by 58.74 ± 5.8% and 76.51 ± 4.27% was observed in microtiter plate assay and tube method, respectively. A significant reduction in exopolysaccharide (EPS) production by 81.29± 2.96% was observed. The swimming and swarming motility were also effectively arrested in presence of BCL-AuNPs. Further, Light microscope and CLSM studies were carried out to examine the effect of BCL-AuNPs on the surface topography and architecture of P. aeruginosa biofilm. Thus, the present study suggests the potential use of BCL-AuNPs in the development of novel therapeutics for the prevention and treatment of biofilm associated chronic infections.
authors.affiliation: Department of Microbiology, School of Life Sciences, Pondicherry University, Puducherry 605014, India.
authors.forename: Jobina
authors.initials: J
authors.lastname: Rajkumari
authors.affiliation: Department of Microbiology, School of Life Sciences, Pondicherry University, Puducherry 605014, India. Electronic address: siddhardha.busi@gmail.com.
authors.forename: Siddhardha
authors.initials: S
authors.lastname: Busi
authors.affiliation: Department of Microbiology, School of Life Sciences, Pondicherry University, Puducherry 605014, India.
authors.forename: Aneesh Cherukunnel
authors.initials: AC
authors.lastname: Vasu
authors.affiliation: Department of Biomedical & Pharmaceutical Sciences, Chapman University, School of Pharmacy, Irvine, CA 92618-1908, USA.
authors.forename: Palarajasekhar
authors.initials: P
authors.lastname: Reddy
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D001672:Biocompatible Materials; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D002712:Chlorides; D004337:Drug Carriers / Q000737:chemistry; D044950:Flavanones / Q000737:chemistry* / Q000494:pharmacology*; D017612:Gold Compounds / Q000737:chemistry*; D055772:Green Chemistry Technology; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D010936:Plant Extracts / Q000737:chemistry; D011135:Polysaccharides, Bacterial / Q000032:analysis; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D002712:Chlorides; D004337:Drug Carriers; D044950:Flavanones; D017612:Gold Compounds; D010936:Plant Extracts; D011135:Polysaccharides, Bacterial; C064841:exopolysaccharide, Pseudomonas; C006680:baicalein; C024568:gold tetrachloride, acid
keywords: Antibiofilm; BCL-AuNPs; Baicalein; EPS; Pseudomonas aeruginosa PAO1; TEM