Green Synthesis of Metal Nanoparticles by Plants: Current Trends and Challenges

Abstract

Metal nanoparticles (MNPs) have been widely used in a range of recent scientifi c and technological applications. They can be produced by conventional chemical synthesis or green synthesis methods. Green synthesis consists of a myriad of promising approaches for the production of MNPs with desired properties. Plants represent the most explored group of living organisms for the green synthesis of MNPs, and to date, hundreds of species have been used. However, several factors that should be taken into account when performing green synthesis of MNPs remain underestimated or unexplored. This chapter does not focus on any specifi c plant species or experimental conditions leading to the synthesis of MNPs since there are numerous recent publications reviewing the literature in this outstanding fi eld. The present chapter instead focuses on the trends and challenges in MNPs synthesis using plants which include reproducibility, scale-up, predictability, and development of strategies for effective management of governance, regulatory, and

<i>Stachytarpheta cayennensis</i> Aqueous Extract, a New Bioreactor towards Silver Nanoparticles for Biomedical Applications

“…The physical and chemical processes of nanoparticles production are typically expensive and require hazardous chemicals while the "green synthesis" approach is environmentally benign and cost-effective. Plants represent the most explored group of living organisms for the green synthesis of nanoparticles [5]. The use of natural products can also lead to capping groups that are biocompatible, circumventing the need for ligand exchange prior to biological applications [6].…”

Green synthesis of metal and metal oxide nanoparticles from plant leaf extracts and their applications: A review

“…The resulted response to the stress factors (pathogens, herbivores, and climate changes) and survival agents (seasonal changes and reproductive manner) concerning plants are affected by the primary and secondary metabolites of the plants, and these strategies will make the plants the main bioreactors and molecule suppliers for green synthesis [48]. Due to the presence of metallic counterparts and the stabilization of the surface of the MNPs and MONPs [41], the primary compounds of plants such as amino acids [49], citric acid [14], flavonoids [50], phenolic compounds [51], terpenoids [52], heterocyclic compounds [53], enzymes [54], peptides [55], polysaccharides [56], saponins [57], and tannis [58] are responsible for the metal ion reduction. The whole organs/ tissues [43,44] or the extracts of the organs/tissues and different parts (e.g., seeds, leaves, barks, roots, and fruits) of the plants are utilized for the green synthesis of MNPs and MONPs and may produce nano-objects with several properties [59,60], so we deal with each part of the plants discretely for their different concentrations and their unique phytochemical characterization, and this depends on the biotic or abiotic stress type to which a plant perhaps subjected and the needs of each organ.…”

“…The next years will prove the importance of green synthesis methods for MNPs and MONPs production because they are not only easy to execute, fast, and cheap but also less toxic and environmentally friendly [347,348], as shown in Figure 17 [41].…”

Síntese Biológica De Nanopartículas Mediada Por Micro-Organismos Endofíticos

“…Para termos cada vez mais avanços, é preciso estar em constante pesquisa, principalmente no âmbito da produção de nanopartículas que de início eram produzidas por métodos químicos e físicos. Atualmente, as nanopartículas podem ser obtidas por meio da síntese biológica, também conhecida como micosíntese, consistindo na formulação de nanossistemas metálicos a partir da redução de um metal utilizando-se organismos biológicos ou parte deles (IRAVANI, 2011;JEYARAJ et al, 2013;SILVA et al, 2015;KHALIL et al, 2017). Esse tipo de síntese apresenta diversas vantagens tendo destaque o menor custo de produção.…”