title: Mechanistic aspects of biologically synthesized silver nanoparticles against food- and water-borne microbes.
abstract: In the present study, silver nanoparticles (AgNPs) synthesized from aqueous leaves extract of Malva crispa and their mode of interaction with food- and water-borne microbes were investigated. Formation of AgNPs was conformed through UV-Vis, FE-SEM, EDS, AFM, and HR-TEM analyses. Further the concentration of silver (Ag) in the reaction mixture was conformed through ICP-MS analysis. Different concentration of nanoparticles (1-3 mM) tested to know the inhibitory effect of bacterial pathogens such as Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, Salmonella typhi, Salmonella enterica and the fungal pathogens of Penicillium expansum, Penicillium citrinum, Aspergillus oryzae, Aspergillus sojae and Aspergillus niger. Interestingly, nanoparticles synthesized from 2 to 3 mM concentration of AgNO3 showed excellent inhibitory activities against both bacterial and fungal pathogens which are well demonstrated through well diffusion, poison food technique, minimum inhibitory concentration (MIC), and minimum fungicidal concentration (MFC). In addition, mode of interaction of nanoparticles into both bacterial and fungal pathogens was documented through Bio-TEM analysis. Further the genomic DNA isolated from test bacterial strains and their interaction with nanoparticles was carried out to elucidate the possible mode of action of nanoparticles against bacteria. Interestingly, AgNPs did not show any genotoxic effect against all the tested bacterial strains which are pronounced well in agarose gel electrophoresis and for supporting this study, UV-Vis and Bio-TEM analyses were carried out in which no significant changes observed compared with control. Hence, the overall results concluded that the antimicrobial activity of biogenic AgNPs occurred without any DNA damage.
authors.affiliation: Department of Food Science and Technology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonju, 561-756, Republic of Korea.
authors.forename: Chandran
authors.initials: C
authors.lastname: Krishnaraj
authors.affiliation: Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR, 97331, USA.
authors.forename: Stacey L
authors.initials: SL
authors.lastname: Harper
authors.affiliation: Department of Animal Biotechnology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonju, 561-756, Republic of Korea.
authors.forename: Ho Sung
authors.initials: HS
authors.lastname: Choe
authors.affiliation: Department of Food Science and Technology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonju, 561-756, Republic of Korea.
authors.forename: Kwang-Pyo
authors.initials: KP
authors.lastname: Kim
authors.affiliation: Department of Food Science and Technology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonju, 561-756, Republic of Korea. siyun@jbnu.ac.kr.
authors.forename: Soon-Il
authors.initials: SI
authors.lastname: Yun
mesh_terms: D000890:Anti-Infective Agents / Q000008:administration & dosage* / Q000138:chemical synthesis; D018407:Bacterial Physiological Phenomena / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D005516:Food Microbiology; D005658:Fungi / Q000187:drug effects* / Q000502:physiology; D028501:Malva / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D012834:Silver / Q000008:administration & dosage* / Q000737:chemistry; D014871:Water Microbiology
chemical_list: D000890:Anti-Infective Agents; D012834:Silver
keywords: AgNPs; Antibacterial; Antifungal; DNA interactions; Malva crispa Linn., leaves extract