Anti‐Allergic and Anti‐Inflammatory Activities of a New Benzodioxane Derivative and Phenolic Compounds From Pharbitis nil Seeds

Pharbitis nil (L.) Choisy is a traditional medicinal plant exhibiting broad-spectrum pharmacological effects, including anti-cancer, renoprotective, and laxative effects; insecticidal activity; and antifungal, anti-inflammatory, antioxidant, neuroprotective, and hepatoprotective actions. In this study, 11 compounds were isolated from the seeds of the plant and structurally characterized. These included one novel benzodioxane derivative named pharbitan A (2), one phenolic compound (1), and nine caffeic acid derivatives (3-11). Bioactivity assays demonstrated that both fractions and isolated compounds from Pharbitis nil seeds significantly inhibited interleukin-4 and histamine secretion in phorbol 12-myristate 13-acetate/ionomycin-induced RBL-2H3 cells, as well as suppressed interlekin-1β production by lipopolysaccharide-stimulated RAW 264.7 macrophages. Notably, compounds 2 and 7 reduced cyclooxygenase-2 expression and modulated mitogen-activated protein kinase signaling pathways through inhibition of p38 MAPK and ERK phosphorylation. These results suggest that Pharbitis nil seeds and their constituents have notable anti-allergic and anti-inflammatory activities, highlighting their potential as natural therapeutic agents.