Biosynthesis of silver nanoparticles from Syzygium cumini leaves and their potential effects on odontogenic pathogens and biofilms

Wagner Luis de Carvalho Bernardo; Marcelo Fabiano Gomes Boriollo; Caroline Coradi Tonon; Jeferson Júnior da Silva; Mateus Cardoso Oliveira; Fernando Cruz de Moraes; Denise Madalena Palomari Spolidorio

doi:10.3389/fmicb.2022.995521

Biosynthesis of silver nanoparticles from Syzygium cumini leaves and their potential effects on odontogenic pathogens and biofilms

Front Microbiol. 2022 Sep 29:13:995521. doi: 10.3389/fmicb.2022.995521. eCollection 2022.

Authors

Wagner Luis de Carvalho Bernardo¹, Marcelo Fabiano Gomes Boriollo², Caroline Coradi Tonon¹, Jeferson Júnior da Silva², Mateus Cardoso Oliveira², Fernando Cruz de Moraes³, Denise Madalena Palomari Spolidorio¹

Affiliations

¹ Department of Physiology and Pathology, School of Dentistry, São Paulo State University, Araraquara, Brazil.
² Department of Oral Diagnosis, Dental School of Piracicaba, State University of Campinas, Piracicaba, Brazil.
³ School of Chemistry, Federal University of São Carlos, São Carlos, Brazil.

Abstract

This study analyzed the antimicrobial and antibiofilm action and cytotoxicity of extract (HEScL) and silver nanoparticles (AgNPs-HEScL) from Syzygium cumini leaves. GC-MS, UV-Vis, EDX, FEG/SEM, DLS and zeta potential assays were used to characterize the extract or nanoparticles. Antimicrobial, antibiofilm and cytotoxicity analyses were carried out by in vitro methods: agar diffusion, microdilution and normal oral keratinocytes spontaneously immortalized (NOK-SI) cell culture. MICs of planktonic cells ranged from 31.2-250 (AgNPs-HEScL) to 1,296.8-10,375 μg/ml (HEScL) for Actinomyces naeslundii, Fusobacterium nucleatum, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mutans, Streptococcus oralis, Veillonella dispar, and Candida albicans. AgNPs-HEScL showed antibiofilm effects (125-8,000 μg/ml) toward Candida albicans, Streptococcus mutans and Streptococcus oralis, and Staphylococcus aureus and Staphylococcus epidermidis. The NOK-SI exhibited no cytotoxicity when treated with 32.8 and 680.3 μg/ml of AgNPs-HEScL and HEScL, respectively, for 5 min. The data suggest potential antimicrobial and antibiofilm action of HEScL, and more specifically, AgNPs-HEScL, involving pathogens of medical and dental interest (dose-, time- and species-dependent). The cytotoxicity of HEScL and AgNPs-HEScL detected in NOK-SI was dose- and time-dependent. This study presents toxicological information about the lyophilized ethanolic extract of S. cumini leaves, including their metallic nanoparticles, and adds scientific values to incipient studies found in the literature.

Keywords: Syzygium cumini; antibiofilm activity; antimicrobial activity; normal oral keratinocytes spontaneously immortalized; odontogenic pathogens; silver nanoparticles.