Biosynthesis of silver nanoparticles using actinomycetes, phytotoxicity on rice seeds, and potential application in the biocontrol of phytopathogens

Autor(es)

Zwar, Ingrid P. ; Trotta, Caterina do Valle ; Ziotti, Ana B. S. ; Neto, Milton Lima ; Araujo, Welington L. ; de Melo, Itamar S. ; Ottoni, Cristiane A. ; de Souza, Ana O.

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF BASIC MICROBIOLOGY; v. 63, n. 1, p. 11-pg., 2022-11-06.

Resumo

To find effective silver nanoparticles (AgNPs) for control of phytopathogens, in this study, two strains of actinomycetes isolated from the soil of the Brazilian biome Caatinga (Caat5-35) and from mangrove sediment (Canv1-58) were utilized. The strains were identified by using the 16S rRNA gene sequencing as Streptomyces sp., related to Streptomyces mimosus species. The obtained AgNPs were coded as AgNPs (35) and AgNPs(58) and characterized by size and morphology using dynamic light scattering, zeta potential, transmission electron microscopy, and Fourier transformed infrared (FTIR). The antifungal activity of the AgNPs(35) and AgNPs(58) was evaluated in vitro by the minimal inhibitory concentration (MIC) assay on the phytopathogens, Alternaria solani, Alternaria alternata, and Colletotrichum gloeosporioides. The phytotoxic effect was evaluated by the germination rate and seedling growth of rice (Oryza sativa). AgNPs(35) and AgNPs(58) showed surface plasmon resonance and average sizes of 30 and 60 nm, respectively. Both AgNPs presented spherical shape and the FTIR analysis confirmed the presence of functional groups such as free amines and hydroxyls of biomolecules bounded to the external layer of the nanoparticles. Both AgNPs inhibited the growth of the three phytopathogens tested, and A. alternate was the most sensible (MIC <= 4 mu M). Moreover, the AgNPs(35) and AgNPs(58) did not induce phytotoxic effects on the germination and development of rice seedlings. In conclusion, these AgNPs are promising candidates to biocontrol of these phytopathogens without endangering rice plants. (AU)

• Processo FAPESP: 18/04258-6 - Impactos da Fotoinibição do Fotossistema I e seus Mecanismos Fotoprotetores sobre a Eficiência Fotossintética
• Beneficiário: Milton Costa Lima Neto
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 10/50186-5 - Utilização de fungos de manguezais na biossíntese de nanopartículas de prata e aplicação na produção de tecidos antimicrobianos
• Beneficiário: Ana Olívia de Souza
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Regular
• Processo FAPESP: 20/12867-2 - Desenvolvimento e validação de uma tecnologia inovadora de baixo custo, baseada em uma bio- e nano- abordagem na desinfecção da água potável
• Beneficiário: Cristiane Angélica Ottoni
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Regular