Park, C.-Y. A special focus has been given on a range of remarkable toxicity mechanisms that underlie this bacterial activity, mainly reactive oxygen species (ROS) generation and Zn2+ release. Technol. doi:10.1021/nl052326h, N. Jones, B. Ray, K.T. The transparent particles, which effectively filter out ultraviolet-a (UVA) and ultraviolet-b (UVB) light, are then coated with inert silicon or aluminum oxide layers and tend to clump together into groups that are 200 to 500 nanometers in diameter. The authors referred that to OH production under light, and they produced a novel ZnO complex. Liu et al. Langmuir 16(6), 2789–2796 (2000). [9] who obtained strong antibacterial activity against E. coli at increased concentration. J. Colloid Interface Sci. by J.A.T. ZnO possesses high optical absorption in the UVA (315–400 nm) and UVB (280–315 nm) regions which is beneficial in antibacterial response and used as a UV protector in cosmetics [25]. Bakhori, A. Sirelkhatim, D. Mohamad, H. Hasan, A. Seeni, R.A. Rahman, Antibacterial responses of zinc oxide structures against Staphylococcus aureus, Pseudomonas aeruginosa and Streptococcus pyogenes. doi:10.1016/j.tifs.2011.01.001, C. Silvestre, D. Duraccio, S. Cimmino, Food packaging based on polymer nanomaterials. Hwang, B. Li, X. Huang, H. Wang, The characterization of various ZnO nanostructures using field-emission SEM. Moreover, isotherms confirmed the mesoporous structure of all ZnO nanoparticles with superior specific surface area and porosity volume. Van de Walle, Fundamentals of zinc oxide as a semiconductor. doi:10.1016/j.freeradbiomed.2011.09.030, D. Guo, H. Bi, B. Liu, Q. Wu, D. Wag, Y. Cui, Reactive oxygen species-induced cytotoxic effects of zinc oxide nanoparticles in rat retinal ganglion cells. Oxygen vacancies are known to increase the generation of ROS and consequently affect the photocatalytic of ZnO [81]. These new materials with improved antimicrobial properties permit also tracking of food during storage and transfer. Biol. Colloids Surf. The spread of foodborne diseases can result in many social problems such as poverty, health problems, and even economic issues. doi:10.1016/j.nano.2010.10.001, J. Sawai, Quantitative evaluation of antibacterial activities of metallic oxide powders (ZnO, MgO and CaO) by conductimetric assay. [79] referred the toxicity of nanostructured ZnO to their orientation, while, it has been found as irrelevant for crystallographic orientation [98]. A number of significant breakthroughs have emerged in the areas of antimicrobial applications, as in the food industry. Imperfection Chemistry of Crystalline Solids (Elsevier, New York, 1974), X. Wang, F. Yang, W. Yang, X. Yang, A study on the antibacterial activity of one-dimensional ZnO nanowire arrays: effects of the orientation and plane surface. J. Phys. 45(5), 1977–1983 (2011). Myint, T. Bora, J. Dutta, Enhanced visible light photocatalysis through fast crystallization of zinc oxide nanorods. 3g). Trends Food Sci. ZnO powder was annealed at 700 °C in an annealing tube furnace (model Lenton) under oxygen ambient for 1 h. The gas flow was regulated at 2.4 L min−1. However, the role of ROS in the antimicrobial actions has become an argument issue among the researchers in this field [13]. These characteristics enable ZnO to have remarkable applications in diverse fields [20]. These compounds act as chemo-therapeutic agents for the treatment or prevention of bacterial infections (Saunders Comprehensive Veterinary Dictionary 2007). Get the latest public health information from CDC:, Get the latest research information from NIH:, Find NCBI SARS-CoV-2 literature, sequence, and clinical content: Res. Res. In other words, MIC is the concentration which impedes and absolutely prevents bacterial growth. Seil, T.J. Webster, Antimicrobial applications of nanotechnology: methods and literature. The functions of this organelle include growth, metabolism, and replication. Additionally, the release of electrons was believed to interact with the bacteria where the electron discharges the bacteria membrane halting the bacterial growth. Int. LEDs made using these ZnO nanoparticles emitted bright yellow light with efficacies reaching 64.2 lm/W. Hassan, M. Elkady, E. Salama, Assessment Of antibacterial activity for synthesized zinc oxide nanorods against plant pathogenic strains. by D.E. 2020 Oct 10;738:140240. doi: 10.1016/j.scitotenv.2020.140240. It was found to be 1.5 and 3.1 mg mL−1 for S. aureus and E. coli, respectively. A goal of this review is to set a well-built reference for scientists interested in antibacterial activities along with their functional applications by considering nanotechnology principles as it relates to the nanobiological toxicity of ZnO-NPs. Goharshadi, M. Abareshi, M. Moosavi, A. Yousefi, P. Nancarrow, ZnO nanofluids: green synthesis, characterization, and antibacterial activity. Particle size and concentration of ZnO-NPs play important roles in the antibacterial activity. The TGA has been continuously monitoring the emerging scientific literature in this area and working cooperatively with international regulatory agencies to ensure that ap… 36(2), 497–506 (2010). Bao, Z. Su, R. Gurwitz, F. Capasso, X. Wang, Z. Ren, Photoinduced oxygen release and persistent photoconductivity in ZnO nanowires. ZnO-doped samples exhibited considerably high activity toward S. aureus (skin bacteria) in comparison to E. coli and P. aeruginosa. Also, they revealed that three strains of this bacterium possess greater degree of susceptibility toward ZnO-NPs, as determined from the MIC (Fig. For discussing MIC and MBC measurements, a comparison between a study reported by Emami-Karvani and Chehrazi [11] and Reddy et al. In case of E. coli O157:H7 (a major foodborne pathogen) showed 100 % growth inhibition in the presence of a ZnO concentration which is approximately 8–32 times that used for C. jejuni. doi:10.1007/s10856-008-3548-5, A.L. Leung, W.K. The bactericidal activity of ZnO-NPs (8–10 nm size) against E. coli DH5α and S. aureus was examined and found to be effective at 80 and 100 µg mL−1. 5a, b, d along with other predicted ones previously mentioned. They concluded that ZnO-NPs synthesized by wet chemical method are potential antibacterial agents in food preservation and packaging. Production of ROS by metal NPs in cell lines has been revealed by several studies [111–113], and referred to the inhibition of the respiratory enzymes [114]. Although the detailed mechanism of ZnO antibacterial activity is under discussion, a three most widely accepted, and reported hypothetical mechanisms in the literature [128] are: (i) metal ions uptake (translocation and particle internalization) into cells followed by depletion of intracellular ATP production and disruption of DNA replication [130], (ii) ROS generation from NPs metal oxides and ions with subsequent oxidative damage to cellular structures [131], and (iii) changes in bacterial membrane permeability (progressive release of lipopolysaccharides, membrane proteins, and intracellular factors) and dissipation of the proton motive force as a result of accumulation and dissolution of NPs in the membrane [132]. 70(1), R1–R10 (2005). Some of the main benefits of using NPs in food nanotechnology are the addition of NPs onto food surfaces to inhibit bacterial growth, also using of NPs as intelligent packaging materials and for nano-sensing [134]. Review on Zinc Oxide Nanoparticles: Antibacterial Activity and Toxicity Mechanism, \({\text{O}}_{2}^{ - } ,\;{\text{O}}_{2}^{2 - }\), $${\text{O}}_{2} \;({\text{g}}) + {\text{e}}^{ - } = {\text{O}}_{2}^{ - } \;({\text{ad}}),$$, $${\text{h}}\upnu \to {\text{e}}^{ - } + {\text{h}}^{ + } ,$$, $${\text{O}}_{2}^{ - } \;({\text{ad}}) + {\text{h}}^{ + } = {\text{O}}_{2} \;({\text{g}}).$$, $${\text{ZnO}} + {\text{h}}\upnu \to {\text{e}}^{ - } + {\text{h}}^{ + } ,$$, $${\text{h}}^{ + } + {\text{H}}_{2} {\text{O}} \to {}^{ \bullet }{\text{OH}} + {\text{H}}^{ + } ,$$, $${\text{e}}^{ - } + {\text{O}}_{2} \to {}^{ \bullet }{\text{O}}_{2}^{ - } ,$$, $${}^{ \bullet }{\text{O}}_{2} + {\text{H}}^{ + } \to {\text{HO}}_{2}^{ \bullet } ,$$, $${\text{HO}}_{2}^{ \bullet } + {\text{H}}^{ + } + {\text{e}}^{ - } \to {\text{H}}_{2} {\text{O}}_{2} .$$, $${\text{DCFH-DA}}\mathop{\longrightarrow}\limits[{\text{esterases}}]{}{\text{DCFH}} \to {\text{DCF}} .$$,, [41]. doi:10.1016/j.colsurfb.2012.07.033, J.M. doi:10.1088/0957-4484/22/10/105101, L. Zhang, Y. Ding, M. Povey, D. York, ZnO nanofluids—a potential antibacterial agent. Leung, A. Djurišić, K.M. A Bactericidal efficacies of ZnO suspensions, for tested samples namely sample 1, sample 2, and bulk with three different particle sizes after 24 h incubation. Environ. doi:10.1007/978-0-387-29185-7_35, Z. Release of Zn2+ ions and adhesion on the cell membrane cause mechanical damage to the cell wall. Each year, 1 million people in the UK acquire foodborne illness, 20,000 people undergo hospitalization, and 500 deaths. Both bacteria showed decreased growth rate at the highest concentration 100 μL, and they explained the growth inhibition as a result of cell membrane damage through penetration of ZnO-NPs. O–ZnO nanowires) through UV light decomposition process. NPs are known as controlled or manipulated particles at the atomic level (1–100 nm). The data showed that ZnO-NPs interacted with E. coli membrane wall resulting in considerable wall damages, which in turn collapsed the cell membrane. 6, it was observed that higher concentration of ZnO caused higher bacterial inhibition. doi:10.1021/jp904864g, J. Díaz-Visurraga, C. Gutiérrez, C. Von Plessing, A. García, in Science and Technology Against Microbial Pathogens Communicating Current Research and Technological Advances: Metal Nanostructures as Antibacterial Agents, ed. 22(11), 595–603 (2011). Antibacterial activity of zinc oxide nanoparticles (ZnO-NPs) has received significant interest worldwide particularly by the implementation of nanotechnology to synthesize particles in the nanometer region. The hexagonal wurtzite structure possesses lattice spacing a = 0.325 nm and c = 0.521 nm, the ratio c/a ~ 1.6 that is very close to the ideal value for hexagonal cell c/a = 1.633. There is a strong trend that considers two mechanisms underlying the interaction of NPs with bacteria, to be mainly concerned [13]: (i) excessive ROS generation, mostly hydroxyl radicals (HO•) and singlet oxygen (1O2) [60, 80, 126, 127], and (ii) NPs precipitation on the bacterial exterior; or NPs gather in the cytoplasmic area or in the periplasm space, thus, disrupt the cellular activities, resulting in membranes disturbance and disorder [7, 40]. 9(3), 035004 (2008). Sci. 6b–d) show ZnO-NPs on the bacteria surfaces, which probably inhibited the growth due to the generated ROS into the mixture of ZnO with E. coli, which was enhanced by the UV exposure and also the annealing process causing oxygen absorption on the surface of ZnO samples. The shape-dependent activity was explained in terms of the percent of active facets in the NPs. Scientific works have elucidated the efficiency of ZnO nanoparticles (NPs) against different cancer cell lines. 5a)., DOI:, Over 10 million scientific documents at your fingertips, Not logged in [50] treated E. coli with a low concentration (1 mM) of solubilized Zn2+. 396(2), 609–618 (2010). Compared with cells exposed to Ag-NPs and ions, the cell energy is reduced due to the decline in the adenosine triphosphate levels and the essential energy molecule, and destabilization of the outer membrane was followed [4]. Amro, L.P. Kotra, K. Wadu-Mesthrige, A. Bulychev, S. Mobashery, G.-Y. Skalska J. Frontczak-Baniewicz M. Strużyńska L. (2015). Total Environ. [91]. Based on the growth curves and percentage viability, their findings revealed that the activity is size dependent, where smaller sized ZnO-NPs possess best antimicrobial action under visible light. Zahidi, M.R. Res. Microbiol. J Agric Food Chem. doi:10.1016/j.jallcom.2011.01.013, J.E. Semin. Losada, B.D. In addition to its unique antibacterial and antifungal properties, ZnO-NPs possess high catalytic and high photochemical activities. Microbiol. Epub 2019 May 31. Yusefi-Tanha E, Fallah S, Rostamnejadi A, Pokhrel LR. 98(4), 041301 (2005). Nanotechnol. doi:10.1016/j.tiv.2009.05.015, T.J. Brunner, P. Wick, P. Manser, P. Spohn, R.N. Functionalized ZnO surface leads to best antibacterial responses. doi:10.1021/nn800511k, R. Prasad, D. Basavaraju, K. Rao, C. Naveen, J. Endrino, A. Phani, Nanostructured Sci. 1a), and the black and gray-shaded spheres symbolize O and Zn atoms, respectively. Technol. World Health Organ 77(8), 651–666 (1999), Y.G. a NPs internalization into the cell and translocation. On the other hand, such doped ZnO can alternatively be used in skin lotions and in UV protection than undoped ZnO. A 165(1), 103–107 (2004). doi:10.1016/j.ijmm.2014.11.005, F. Kroger, The Chemistry of Imperfect Crystals. Ag-loaded ZnO speculated as a new kind of precursor for inorganic antibacterial agents. Oxygen annealing stimulated a high amount of oxygen atoms to be absorbed onto ZnO surface, thereby enhanced antibacterial response inducing more ROS in the suspension resulting in intense oxidative stress towards the bacteria. This might be probably suggested that the size of the particles did not allow their penetration into the cell wall and membrane. doi:10.1021/es052069i, M. Li, L. Zhu, D. Lin, Toxicity of ZnO nanoparticles to Escherichia coli: mechanism and the influence of medium components. Mater. of an ultraviolet photoconductive sensor using well-aligned aluminium-doped zinc-oxide nanorod arrays annealed in an air and oxygen environment. Keywords: Chem. Stark, In vitro cytotoxicity of oxide nanoparticles: comparison to asbestos, silica, and the effect of particle solubility. ZnO-NPs concentrations that are 20–100 times were required for decreasing 1–2 logs of cells viability. Appl. doi:10.1088/0953-8984/16/25/R01, Z.L. Barry, W.A. Lopez, J. Miltz, M.A. Nanoscale 5(9), 3834–3840 (2013). Sanders, J.M. 274(15), 10119–10128 (1999). Increased cell death achieved by increasing ZnO concentrations, which disrupt mitochondrial function, stimulating lactate dehydrogenase leakage and changing the morphology of the cell at concentrations of 50–100 mg L−1 [90]. J. Ferment. J. 127(50), 17600–17601 (2005). An antibacterial agent is considered as bactericidal if it kills bacteria or as bacteriostatic if it inhibits their growth. With unexposed ZnO several studies have addressed the antibacterial activity of zinc oxide particles: synthesis and characterization of nanowires... Motivated to achieve novel way of packaging that mainly meet the requirements of protection against bacteria under different test [! Review aimed to discuss and analyze research works that addressed the antibacterial influence of particle [! 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