title: Antibacterial and DNA degradation potential of silver nanoparticles synthesized via green route.
abstract: Silver nanoparticles (AgNPs) were synthesized using a hetero polysaccharide (PS) isolated from Lentinus squarrosulus (Mont.) Singer. The polysaccharide fraction (consisting of glucose, fucose and galactose) serves the role of both reducing as well as stabilizing agent. UV-vis spectroscopy showed maximum absorbance at 407 nm due to surface plasmon resonance. High resolution transmission electron microscopy (HRTEM) exhibited that the average diameter of the nanoparticles was 2.78±1.47 nm. The XRD analysis revealed face-centered cubic (fcc) geometry of silver nanoparticles. Antibacterial activity of the AgNPs-PS conjugate was tested against multiple antibiotics resistant (MAR) Escherichia coli strain MREC33 and found that the killing was due to generation of reactive oxygen species (ROS). Internalization of AgNPs-PS conjugate along with its DNA degradation capability was demonstrated using flow cytometry. AgNPs-PS conjugates showed negligible toxicity to human RBCs. This LD50 dosage of AgNPs-PS conjugates in combination with each of the four antibiotics (ampicillin, azithromycin, kanamycin and netilmicin) to which E. coli MREC33 was resistant, showed synergistic effect to inhibit complete bacterial growth.
authors.affiliation: Department of Chemistry and Chemical Technology, Vidyasagar University, Midnapore 721102, West Bengal, India.
authors.forename: Dilip K
authors.initials: DK
authors.lastname: Manna
authors.affiliation: Department of Microbiology, Vidyasagar University, Midnapore 721102, West Bengal, India; Omics Laboratory, Department of Biotechnology, North Bengal University, Siliguri 734013, West Bengal, India.
authors.forename: Amit K
authors.initials: AK
authors.lastname: Mandal
authors.affiliation: Department of Chemistry and Chemical Technology, Vidyasagar University, Midnapore 721102, West Bengal, India.
authors.forename: Ipsita K
authors.initials: IK
authors.lastname: Sen
authors.affiliation: Department of Chemistry and Chemical Technology, Vidyasagar University, Midnapore 721102, West Bengal, India.
authors.forename: Praloy K
authors.initials: PK
authors.lastname: Maji
authors.affiliation: Department of Biochemistry, Bose Institute, P1/12 CIT Scheme VIIM, Kolkata 700054, India.
authors.forename: Soumyananda
authors.initials: S
authors.lastname: Chakraborti
authors.affiliation: Omics Laboratory, Department of Biotechnology, North Bengal University, Siliguri 734013, West Bengal, India.
authors.forename: Ranadhir
authors.initials: R
authors.lastname: Chakraborty
authors.affiliation: Department of Chemistry and Chemical Technology, Vidyasagar University, Midnapore 721102, West Bengal, India. Electronic address: sirajul_1999@yahoo.com.
authors.forename: Syed S
authors.initials: SS
authors.lastname: Islam
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D053938:DNA Fragmentation; D024901:Drug Resistance, Multiple, Bacterial; D004357:Drug Synergism; D004912:Erythrocytes / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D055772:Green Chemistry Technology; D006801:Humans; D007928:Lethal Dose 50; D053768:Metal Nanoparticles / Q000737:chemistry; D008826:Microbial Sensitivity Tests; D017382:Reactive Oxygen Species / Q000378:metabolism; D012835:Silver Nitrate / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D017382:Reactive Oxygen Species; D012835:Silver Nitrate
keywords: AgNPs–PS conjugates; Antibacterial activity; Multiple antibiotic resistant