Isolation, Characterization & Pharmacological Evaluation of Carotinoids Fractions from Flowers of Nyctanthes arbor-tirstis with Special Reference to Antioxidant Activity

Abstract

Nyctanthes arbor-tristis is a medicinal plant traditionally used for managing inflammation, fever, and skin diseases. Although its iridoid glycosides and phenolics are well-studied, its carotenoid profile—responsible for the vivid orange color of its corolla tube—remains poorly documented. This research investigates carotenoid-rich extracts from N. arbor-tristis flowers through high-level extraction, spectrophotometric analysis, chromatographic profiling, mass spectrometric characterization, and antioxidant evaluations. Extraction produced 2.84% (w/w) carotenoid-rich oleoresin. UV–Vis analysis revealed characteristic carotenoid absorption maxima at 422, 445, and 472 nm. HPLC–DAD analysis identified lutein (36.2%), zeaxanthin (21.4%), and β-carotene (28.1%) as major carotenoids, alongside minor xanthophyll derivatives. LC–MS/MS confirmed molecular masses consistent with these compounds. The extract displayed moderate-to-strong antioxidant potential, with IC₅₀ values of 42.6 μg/mL (DPPH) and 31.3 μg/mL (ABTS). This study confirms that N. arbor-tristis flowers are a rich source of bioactive carotenoids and supports their potential use in nutraceutical, cosmetic, and phytopharmaceutical applications.