Exploring the role of different phytochemicals on the morphological variations of metal and metal oxide nanomaterials for biomedical application

Plant-mediated synthesis of nanoparticles (NPs) has emerged as an eco-friendly and cost-effective method, utilizing the reducing and capping properties of plant extracts for NPs fabrication. This review explores the influence of various plant parts such as leaves, seeds, roots, fruits, and flowers, on the morphology, size, and antibacterial activity of metal and metal-oxide NPs. Through comprehensive analysis of numerous studies, we elucidate how plant-derived carbohydrates and other phytochemicals impact the synthesis and characteristics of NPs. Nanoparticles synthesized with different parts of plants have successfully proved as antibacterial agents displaying significant zone of inhibition (ZOI). For instance, green tea leaf extract yields spherical silver NPs (15–33 nm) with potent antibacterial properties of ZOI of 11 mm and 10 mm toward S. aureus and K. pneumoniae, while Trigonella foenum-graecum seed extracts result in irregularly spherical zinc oxide (ZnO) NPs (70–90 nm) effective against bacterial strains. Moringa oleifera root extracts lead to the formation of hexagonal-shaped ZnO NPs (15–40 nm) with significant antibacterial activity with ZOI of 11.6 mm and 12.5 mm against B. subtilis and E. coli, and Myristica fragrans fruit extracts produce elliptical and spherical NPs (41.23 nm) effective against various bacterial strains such as E. coli (ZOI = 15 mm), S. aureus (ZOI = 21 mm), and K. pneumoniae (ZOI = 27 mm). Cassia auriculata flower extracts generate flake-structured NPs (41 nm) with potent antibacterial action against E. coli, S. aureus, K. pneumoniae, S. pneumoniae. This review highlights the innovative potential of plant-mediated nanoparticle synthesis and emphasizes the importance of selecting specific plant's part by understanding the unique contributions of its phytochemicals to tailor NPs properties for diverse applications, particularly in the development of effective antibacterial formulations.