Gold Nanoparticles in Plant Physiology: Principal Effects and Prospects of Application

Reduced Genotoxicity of Gold Nanoparticles With Protein Corona in Allium cepa

“…These studies suggested that AuNPs induce genotoxicity by generating oxidative stress in the root cells in a dose dependent manner. Interestingly, several studies have shown that at much higher concentrations (400–1,000 µg/ml), AuNPs can promote growth and germination in rice ( Oryza sativa ) ( Ndeh et al, 2017 ), Mung Bean ( Vigna radiata ) ( Das et al, 2017 ), and other plant species ( Venzhik et al, 2021 ). However, there is no report that evaluates and compares, on plants, the effect of AuNPs with and without PC.…”

“…Contrary to the above findings, AuNPs synthesized using Sphaeranthus indicus extract (1–10%) promoted mitotic cell division in A. cepa root tips depending on the concentration of extract used, with 10% of extract synthesized AuNPs showing the highest mitotic index ( Balalakshmi et al, 2017 ). Similarly, studies performed on Oryza sativa ( Ndeh et al, 2017 ), Vigna radiata ( Das et al, 2017 ), and several other species ( Venzhik et al, 2021 ), showed that AuNPs have the potential to enhance germination rate, growth and photosynthesis at higher concentrations, i.e., 10–1,000 µg/ml. Such contradictory observations towards AuNPs suggest that, AuNPs, irrespective of their origin and application, should be tested for the presence of off-target effects at high concentrations.…”

Influence of metallic, metallic oxide, and organic nanoparticles on plant physiology

“…On the contrary, the application of TiO 2, Au, CuO, ZnO, CeO 2 , and NPs negatively affected the photosynthetic parameters of Ulmus elongata seedlings, H. vulgare, O. sativa, Gossypium herbaceum, C. sativus, T. aestivum, R. sativus, A. thaliana, and Clarkia unguiculate (Du et al, 2017;Venzhik et al, 2021). Nevertheless, plants like kidney bean, corn, rice, pepper, cucumber, zucchini, and lettuce were unaffected when Au and CeO 2 NPs were applied in terms of their photosynthetic potential (Venzhik et al, 2021).…”

“…An improvement in photosynthetic parameters, such as oxygen emission and the Hill reaction, chlorophyll, carotenoids, and proline contents, Rubisco expression, leaf relative water content, and the photosynthetic rate has been documented for C. pepo, S. lycopersicum, Ocimum basilicum, Moringa peregrina, Helianthus annuus, C. arietinum, B. chinensis, G. max and Pelargonium zonale upon application of SiO 2, ZnO and Fe 3 O 4 , ZnO, TiO 2 , Na 2 SeO 4 , hydroxyapatite, TiO 2 , Al 2 O 3 , Au, and Ag-NPs (Du et al, 2017;Khan et al, 2017;Venzhik et al, 2021). On the contrary, the application of TiO 2, Au, CuO, ZnO, CeO 2 , and NPs negatively affected the photosynthetic parameters of Ulmus elongata seedlings, H. vulgare, O. sativa, Gossypium herbaceum, C. sativus, T. aestivum, R. sativus, A. thaliana, and Clarkia unguiculate (Du et al, 2017;Venzhik et al, 2021). Nevertheless, plants like kidney bean, corn, rice, pepper, cucumber, zucchini, and lettuce were unaffected when Au and CeO 2 NPs were applied in terms of their photosynthetic potential (Venzhik et al, 2021).…”

Adaptation of a Bacterial Bioluminescent Assay to Monitor Bioeffects of Gold Nanoparticles

“…Our current paper focuses on adapting the bacteria-based bioluminescent assay to investigate the bioeffects of gold nanoparticles (AuNPs). AuNPs have been extensively studied and are considered one of the most chemically neutral carriers of bioactive compounds and ligands in targeting local bioprocesses in organisms [61][62][63][64]. This study is necessary (1) to provide a consistent comparison of AuNP bioeffects with other nanoparticles and to compare these bioeffects with those of nanostructures previously studied using similar techniques and (2) to develop, through this, a classification of NP bioeffects based on structural characteristics, i.e., core type and surface modification.…”