Biofabrication of Zinc Oxide Nanoparticle fromOchradenus baccatusLeaves: Broad-Spectrum Antibiofilm Activity, Protein Binding Studies, andIn VivoToxicity and Stress Studies

Abstract

Biofilms are complex aggregation of cells that are embedded in EPS matrix. These microcolonies are highly resistant to drugs and are associated with various diseases. Biofilms have greatly affected the food safety by causing severe losses due to food contamination and spoilage. Therefore, novel antibiofilm agents are needed. This study investigates the antibiofilm and protein binding activity of zinc nanoparticles (ZnNPs) synthesized from leaf extract of Ochradenus baccatus. Standard physical techniques, including UVvisible spectroscopy Fourier transform infrared spectroscopy and X-ray diffraction and transmission electron microscopy, were used to characterize the synthesized OB-ZnNPs. Synthesized OB-ZnNPs demonstrated significant biofilm inhibition in human and food-borne pathogens (Chromobacterium violaceum, Escherichia coli, P. aeruginosa, Klebsiella pneumoniae, Serratia marcescens, and Listeria monocytogenes) at subinhibitory concentrations. OB-ZnNPs significantly reduced the virulence factors like violacein, prodigiosin, and alginate and impaired swarming migration and EPS production. OB-ZnNPs demonstrated efficient binding with HSA protein and no change in their structure or stability was observed. In addition, in vivo toxicity evaluation confirmed that OBZnNPs possessed no serious toxic effect even at higher doses. Moreover, they were found to have excellent antioxidant properties that can be employed in the fields of food safety and medicine. Hence, it is envisaged that the OB-ZnNPs can be used as potential nanomaterials to combat drug resistant bacterial infections and prevent contamination/spoilage of food.

Facile Synthesis of Tin Oxide Hollow Nanoflowers Interfering with Quorum Sensing-Regulated Functions and Bacterial Biofilms

“…Alginate production was impaired by 19-50% at concentrations ranging from 8 to 64 μg/ml (Figure 8). Our results are in accordance with observations on green synthesized zinc oxide particles that arrested alginate production by 34-74% at tested sub-MICs [53].…”

“…The untreated control showed thick aggregation of cells in all pathogens whereas TONF-treated bacteria showed disturbed architecture of microcolonies. A similar dose-dependent reduction of biofilm in pathogenic bacteria has been described with silver nanoparticles [45,55], zinc oxide nanoparticles [52,53], iron oxide nanoparticles [56], and copper oxide nanoparticles [57].…”

“…This drop in prodigiosin production by S. marcescens was found to be significant at all tested concentrations (p ≤ 0 05). Al-Shabib et al [53] demonstrated 60% reduction in prodigiosin at 50 μg/ml concentration of zinc oxide nanoparticles. This finding corresponds to our results on prodigiosin reduction.…”

Biogenesis of ZnO nanoparticles using Pandanus odorifer leaf extract: anticancer and antimicrobial activities

“…It is significant to note that the growth of both B. subtilis and E. coli was signicantly inhibited by ZnO NPs at least at 40-80 mg ml À1 , which is in agreement with the ndings of previous studies on biologically synthesized ZnO NPs. 66 Similarly, the bactericidal activity of the ZnO NPs against Campylobacter jejuni, Salmonella enterica, and Escherichia coli has been previously reported. [67][68][69] The bactericidal effect of the ZnO NPs might be attributed to disruption of the bacterial cell membrane.…”

“…Similarly, in previous studies, inorganic/biogenic ZnO nanomaterial was also used as an antibacterial agent. 66,68 During zone inhibition assay, nanomaterials stored in the wells of bacterial culture inoculated plate, here nanomaterials release and diffuse ions into the surrounding media where these ions interact with the inoculated bacteria and signicantly prevent the growth of bacteria around the wells and develop a clear halo.…”