LC-MS/MS-QTOF Based Phytochemical Characterization and In Vitro Pharmacological Potentials of the Endemic Variety, Humboldtia brunonis var. raktapushpa.

Humboldtia (Fabaceae), an endemic genus of Western Ghats (India), comprises several ecologically and ethnobotanically important species. The present study reports the first comprehensive evaluation of the phytochemical composition and in vitro antioxidant, anti-inflammatory, enzyme inhibition, and cytotoxic potential of Humboldtia brunonis var. raktapushpa, an endemic variety to its type locality. The phytochemical profiling using LC-MS/MS-QTOF tentatively identified diverse bioactive compounds, predominantly polyphenols, flavonoids, including quinic acid, (-)-epicatechin, asperuloside, chlorogenic acid, vanillic acid, butin, kaempferol, quercetrin, genistein, luteolin, hyperforin, and so forth. The extracts exhibited strong antioxidant activity with low IC50 values in DPPH (12.96 ± 0.071 µg/mL) and ABTS (3.79 ± 0.003 µg/mL) assays. Although enzyme inhibitory action was weak, the extract reduced proinflammatory cytokine levels in LPS-induced macrophage cells and showed in vitro cytotoxicity towards the MCF-7 cancer cell line. These results highlight its potential for natural product-based drug discovery and thereby conservation of the endemic plant resources.