Health-promoting activities of clove (Syzygium aromaticum) extracts

Abstract

Clove (Syzygium aromaticum or Eugenia caryophyllus) is a tropical plant in the Myrtaceae family with aromatic flower buds (Ryu et al., 2016). It can be classified as a large-leaved evergreen species, with a height between 8 and 12m tall and crimson flowers grouped in terminal clusters (El-Shouny et al., 2019). The clove flower buds are initially pale hue; however, they transit to a bright red color when ready to be harvested at 1.5–2 cm long (Singh et al., 2018). The S. aromaticum dried flower buds are among the most valuable spices with a long history of applications in pharmaceutical, cosmetic, food, and agricultural industries (Cort es-Rojas et al., 2014). Because of these, cloves are now commercially farmed in different places worldwide, although they are known to be native to Maluku Islands in eastern Indonesia (Lambert et al., 2020). The world’s top producers of cloves are Indonesia, India, Malaysia, Sri Lanka, West Indies, Madagascar, Tanzania, and Comoros (Idowu et al., 2021). The ethnobotanical knowledge of clove provides a bird’s eye view to understand a wide range of beneficial health-promoting activities, active biological properties, and unique aromatic structures (Cort es-Rojas et al., 2014). For instance, in Indian and Chinese traditional medicine, clove was documented to treat diverse complications like arthritis, digestive disorders, erectile dysfunction, diabetes, coughs and colds, diarrhea, toothaches, vomiting, memory loss, and nausea (Batiha et al., 2020). Over the last few years, numerous research studies have attempted to provide scientific evidence of the biological activities of clove as a potential drug candidate for these ailments (Cort es-Rojas et al., 2014; Ajiboye et al., 2016; Rad€unz et al., 2019; Batiha et al., 2020). Some of these studies were focused on the effects of clove toward suppression of microbial growth, improvement of neurological problems, and diabetes symptoms (Singletary, 2014). On the other hand, other preclinical studies supported the contribution of clove to counteract inflammation, inhibit oxidative stress, and oppose processes associated with cardiovascular disease (El-Maati et al., 2016; Mittal et al., 2014). Interestingly, various constituents of S. aromaticum were analyzed to determine the relationship between pharmacological activity and a diverse array of secondary metabolites toward a wide range of beneficial healthpromoting activities, active biological properties, and unique aromatic structures (Mittal et al., 2014; Oliveira et al., 2016). This chapter gives insights into the effects of clove extracts on health promotion and their potential applications.