Neuroprotective Properties of Clove (Syzygium aromaticum): State of the Art and Future Pharmaceutical Applications for Alzheimer's Disease

Abstract

This study explores the neuropharmacological potential of various molecular and amino acid components derived from Syzygium aromaticum (clove), an aromatic spice with a long history of culinary and medicinal use. Key bioactive compounds such as eugenol, α-humulene, β-caryophyllene, gallic acid, quercetin, and luteolin demonstrate antioxidant, anti-inflammatory, and neuroprotective properties by scavenging free radicals, modulating calcium channels, and reducing neuroinflammation and oxidative stress. Moreover, gallic acid and asiatic acid may exhibit protective effects, including neuronal apoptosis inhibition, while other useful properties of clove phytocompounds include NF-κB pathway inhibition, membrane stabilization, and suppression of pro-inflammatory pathways, possibly in neurons or other relevant cell types, further contributing to neuroprotection and cognitive enhancement. Amino acid analysis revealed essential and non-essential amino acids such as aspartic acid, serine, glutamic acid, glycine, histidine, and arginine in various clove parts (buds, fruits, branches, and leaves). These amino acids play crucial roles in neurotransmitter synthesis, immune modulation, antioxidant defense, and metabolic regulation. Collectively, these bioactive molecules and amino acids contribute to clove's antioxidant, anti-inflammatory, neurotrophic, and neurotransmitter-modulating effects, highlighting its potential as a preventive and therapeutic candidate for neurodegenerative disorders. While preliminary preclinical studies support these neuroprotective properties, further research, including clinical trials, is needed to validate the efficacy and safety of clove-based interventions in neuroprotection.

Keywords: Alzheimer’s disease; cloves; herbal medicine; neurodegeneration; nutrition.

Figure 1

Chemical representations of the phytocompounds found in clove discussed in this section for their neuroprotective properties.

Figure 2

Three-dimensional structure of human ghrelin within its precursor protein, as accessed from https://www.modelarchive.org/doi/10.5452/ma-cfzyt (accessed on 15 February 2025) [156].