• Gramine is a multifunctional indole alkaloid with ecological, pharmacological, and translational relevance. • Botanical sources, physicochemical properties, and optimized extraction and isolation strategies are comprehensively summarized. • Chemical synthesis routes and recently elucidated biosynthetic pathways of gramine are critically integrated. • Diverse biological and pharmacological activities of gramine are evaluated with mechanistic insights and limitations. • Nanotechnology-driven delivery systems are highlighted as promising strategies to enhance gramine’s therapeutic potential. • Patent landscape analysis reveals emerging innovation trends and future translational opportunities for gramine-based applications. Plant-derived indole alkaloids remain important scaffolds for drug discovery and agro-biotechnological research. Gramine (N,N-dimethyl-1H-indole-3-methylamine), a structurally simple indole alkaloid predominantly found in barley and related plant species, has attracted sustained interest due to its defined roles in plant defence and its amenability to chemical modification. While gramine exhibits a range of biological activities in vitro and in vivo including antibacterial, antifungal, antiviral, anti-inflammatory, anticancer, antioxidant, neuroprotective, and cardioprotective effects, its intrinsic pharmacological potency is generally modest, and its translational development is constrained by limited pharmacokinetic characterization and incomplete toxicological evaluation. This review provides an integrated overview of gramine, covering its botanical sources, physicochemical properties, extraction and isolation methods, biosynthetic pathways, and established synthetic routes. Reported biological activities are critically assessed with emphasis on mechanistic insights, comparative potency, and limitations of the parent compound relative to structurally modified derivatives. Particular attention is given to chemical derivatization strategies that enhance biological efficacy and selectivity. Nanotechnology-driven delivery approaches are discussed primarily as emerging and adaptive strategies, informed by experimental studies on gramine-loaded formulations and by established delivery platforms for structurally related alkaloids, with a critical appraisal of their current experimental validation and translational readiness. In addition, the evolving patent landscape is examined to contextualize innovation trends and industrial interest. Overall, this review positions gramine as a versatile indole alkaloid scaffold rather than a mature drug candidate, highlighting how rational derivatization and formulation strategies may enable future translational applications in pharmaceutical, agricultural, and biotechnological domains.
Hashmi et al. (Sun,) studied this question.