Health and therapeutic potentials of Ocimum essential oils: a review on isolation, phytochemistry, biological activities, and future directions

Abstract

Ocimum species, including African basil (Ocimum gratissimum) and Holy basil (Ocimum sanctum), are valued for their diverse therapeutic properties particularly in the form of essential oils (EOs). This review provides a comprehensive analysis of the health and therapeutic potentials of Ocimum essential oils, specifically focusing on African and Holy basil. It encompasses various aspects, such as isolation methods, phytochemical characterization, bioactivities, bioavailability, and future directions. Various studies have highlighted the bioactive compounds within these EOs, such as eugenol, camphor, and α-pinene, attributing to their wide-ranging health benefits. Notably, Ocimum EOs exhibit potent antimicrobial, antioxidant, anti-inflammatory, antidiabetic, and anticancer properties, making them promising candidates for alternative medicine and pharmaceutical applications. However, the rapid absorption and poor bioavailability of EOs pose challenges, mitigated through nanoencapsulation techniques enhancing their efficacy. Future research directions include mechanistic studies utilizing specialized cell cultures and animal models, alongside clinical trials to validate reported bioactivities. Optimization of delivery systems and exploration of novel nano-formulations are also essential for optimizing the complete therapeutic potential of Ocimum essential oils. Lastly, efforts to enhance EO yield and augment bioactivity through genetic strategies and elicitation techniques have been suggested.