THUNBERGIA- DISTRIBUTION, TAXONOMY AND PHARMACOGNOSY: A SYSTEMATIC REVIEW

Abstract

Thunbergia is a versatile genus within the Acanthaceae family comprising over 100 species valued for their ornamental appeal and ethnomedicinal significance. Distributed predominantly across tropical and subtropical regions of Asia and Africa, several species—particularly T. laurifolia, T. erecta, and T. grandiflora—have long been used in traditional medicine for managing inflammatory, microbial, hepatic, and metabolic disorders. This systematic review aims to summarize and critically evaluate scientific literature published between 2015 and 2025 on the taxonomy, phytochemistry, pharmacognostic features, and therapeutic applications of Thunbergia, following PRISMA guidelines. An initial search on the Scopus database using “Thunbergia” yielded 2,612 records, of which 58 peer-reviewed full-text articles met the inclusion criteria and were analyzed qualitatively. Data extraction focused on taxonomic characteristics, anatomical features, phytochemical constituents, ethnomedicinal uses, and pharmacological activities. Research output was highest in India and Malaysia, with T. laurifolia and T. erecta emerging as the most extensively studied species. Key bioactive compounds included flavonoids (luteolin, apigenin), alkaloids, phenolics, and saponins, demonstrating antioxidant, anti-inflammatory, antimicrobial, hepatoprotective, and antidiabetic effects. Mechanistic studies indicated modulation of NF-κB, Nrf2, and PI3K/Akt pathways. Emerging formulations such as nanoemulsions and hydrogels enhanced bioavailability. Overall, Thunbergia shows promising pharmacological potential, warranting further molecular studies, clinical trials, and standardization.