title: Biochemical changes in cyanobacteria during the synthesis of silver nanoparticles.
abstract: The methods of synthesis of silver (Ag) nanoparticles by the cyanobacteria Spirulina platensis and Nostoc linckia were studied. A complex of biochemical, spectral, and analytical methods was used to characterize biomass and to assess changes in the main components of biomass (proteins, lipids, carbohydrates, and phycobilin) during nanoparticle formation. The size and shape of Ag nanoparticles in the biomass of both types of cyanobacteria were determined. Neutron activation analysis was used to study the accumulation dynamics of the Ag quantity. The analytical results suggest that the major reduction of Ag concentration in solutions and the increase in biomass occur within the first 24 h of experiments. While in this time interval minor changes in the N. linckia and S. platensis biomass took place, a significant reduction of the levels of proteins, carbohydrates, and phycobiliproteins in both cultures and of lipids in S. platensis was observed after 48 h. At the same time, the antiradical activity of the biomass decreased. The obtained results show the necessity of determining the optimal conditions of the interaction between the biomass and the solution containing Ag ions that would allow nanoparticle formation without biomass degradation at the time of Ag nanoparticle formation by the studied cyanobacteria.
authors.affiliation: a Institute of Microbiology and Biotechnology of the Academy of Science of Moldova, 1, Academiei Str., 2028 Chisinau, Republic of Moldova.
authors.forename: L
authors.initials: L
authors.lastname: Cepoi
authors.forename: L
authors.initials: L
authors.lastname: Rudi
authors.forename: T
authors.initials: T
authors.lastname: Chiriac
authors.forename: A
authors.initials: A
authors.lastname: Valuta
authors.forename: I
authors.initials: I
authors.lastname: Zinicovscaia
authors.forename: Gh
authors.initials: G
authors.lastname: Duca
authors.forename: E
authors.initials: E
authors.lastname: Kirkesali
authors.forename: M
authors.initials: M
authors.lastname: Frontasyeva
authors.forename: O
authors.initials: O
authors.lastname: Culicov
authors.forename: S
authors.initials: S
authors.lastname: Pavlov
authors.forename: I
authors.initials: I
authors.lastname: Bobrikov
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis / Q000378:metabolism; D018533:Biomass; D050260:Carbohydrate Metabolism; D002241:Carbohydrates / Q000032:analysis; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis; D053758:Nanoparticles / Q000737:chemistry / Q000378:metabolism*; D046937:Nostoc / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*; D010316:Particle Size; D012834:Silver / Q000378:metabolism*; D053545:Spirulina / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D002241:Carbohydrates; D008055:Lipids; D012834:Silver
keywords: Nostoc linckia; Spirulina platensis; analyse biochimique; argent; biochemical analysis; méthodes optiques et analytiques; nanoparticles; nanoparticules; optical and analytical methods; silver