Micropropagation and Phytochemical Research in Aerva lanata: A Critical Synthesis of Regeneration Systems, Metabolite Evidence and Translational Priorities

Abstract

Aerva lanata (L.) Juss. ex Schult. is a medicinally important amaranthaceous taxon used particularly in South Asian and African traditions for urinary, renal, metabolic and inflammatory disorders. Research on the plant has developed along two largely parallel tracks: protocols for clonal multiplication and in vitro culture, and phytochemical investigations of field-derived or cultured material. This critical narrative review integrates those tracks to determine whether available biotechnology can provide genetically and chemically reliable plant material, and whether the phytochemical evidence is sufficiently mature to guide standardisation or bioprocess development. Literature published principally from 1990 to 30 May 2026 was identified through accessible scholarly indexes, bibliographic databases, DOI registries, institutional repositories and citation searching. Evidence was appraised for botanical authentication, experimental design, replication, analytical specificity, comparability and translational relevance. Nodal and leaf explants have both supported efficient regeneration, with thidiazuron-rich systems generally producing the highest reported shoot numbers, while benzylaminopurine-based nodal culture offers a more conservative route that may reduce callus-associated variation. Liquid culture improves multiplication, but evidence for bioreactor scale-up, long-term subculture stability and clonal fidelity remains sparse. Phytochemical studies consistently indicate alkaloids, flavonoids, phenolic acids, terpenoids, steroids and glycosides, yet much of the literature relies on preliminary screening or chromatographic fingerprints rather than validated quantitative metabolomics. Stronger chemical evidence centres on canthin-6-one and beta-carboline alkaloids, including aervine and methylaervine, and on selected phenolic and flavonoid constituents. Hairy-root, callus and adventitious-shoot cultures demonstrate that targeted elicitation can enhance metabolite accumulation, but cross-study comparisons are constrained by inconsistent biomass normalisation, limited genetic controls and weak linkage between compound yield and pharmacological potency. The field should therefore move from protocol optimisation in isolation towards authenticated germplasm, multi-locus fidelity testing, validated chemical markers, paired field-versus-culture metabolomics, process engineering and safety-aware bioactivity assessment. Such integration is necessary before micropropagation can reliably support conservation, quality-controlled cultivation or industrial phytochemical production.