Clove (Syzygium aromaticum)- mediated metallic nanoparticles: synthesis, characterization, and possible pharmacological and industrial applications

Abstract

Nanotechnology offers practical applications to different fields, stretching from chemical techniques to environmental and medicinal innovations. This is mainly because nanomaterials have completely different physicochemical from individual atoms, compounds, and bulk materials (Etheridge et al., 2013). Nowadays, NPs are being explored for a plethora of industrial applications such as electronics, energy, water purification, agriculture, and cosmetics (Kargozar and Mozafari, 2018). Different types of NPs have been studied extensively for biomedical applications like drug delivery, medical imaging, diagnosis, and therapeutics (Ramos et al., 2017). Several metal precursors have been used to synthesize MNPs in mono and multimetallic forms. MNPs possess unique optoelectrical properties due to their localized surface plasmon resonance, which can be utilized in several applications (Khan et al., 2019). Applying these MNPs in the different fields is dependent on the type of metal(s) used. To exemplify, the metal silver has been historically known for its antibacterial activity (Clement and Jarrett, 1994), and consequently, AgNPs are mainly studied for their antibacterial potential (Le Ouay and Stellacci, 2015). Plant phytochemicals have enabled researchers to green synthesize and stabilize MNPs without the need for applying expensive, toxic, and environmentally harmful materials in the conventional chemical synthesis methods (Gour and Jain, 2019). Besides contributing to the synthesis, these phytochemicals surround the MNPs rendering them more biologically active (Afreen et al., 2020). The widely used Indonesian spice Syzigium aromaticum (L.) (clove) belongs to the family Myrtaceae (Batiha et al., 2019). The aromatic, nail-shaped CB is a clove’s dried, unopened flower bud (Adaramola and Onigbinde, 2016). The traditional use of cloves is known, which is also supported by the scientific reports that investigated the clove’s extracts, essential oil, and isolated compounds for their antiseptic (Meeker and Linke, 1988), antibacterial (Ajiboye et al., 2016), antifungal (Kaur et al., 2019), antiviral (Cort es-Rojas et al., 2014), and anticancer activities (Banerjee, 2005). Clove essential oil has enormous applications in the food, sanitary, biomedical, pharmaceutical, active packaging, and cosmetics industries due to its biological properties, including antioxidant, antimicrobial, antiseptic, analgesic, and anticancer activities (Nowak et al., 2012). A recent review by Batiha et al. (2019) summarizes the reports describing the traditional use, chemical constituents, and the pharmacological actions of different clove components.