Polyphenols in Different Plant Parts of Inula grandiflora Collected from Two Habitats of Uttarakhand Himalayas

The phytoconstituent analyses have been undertaken for the first time from the different plant parts of Inula grandiflora Willd. collected from two habitats (open dry slopes and moist places) of Govind Pashu Vihar National Park and Wildlife Sanctuary, Uttarakhand, India. The total phenolic and flavonoid contents and antioxidant activity have been estimated from the methanolic extracts. Ten phenols and five flavonoids were quantified in the different parts using High Performance Liquid Chromatography-Photodiode Array Detection (HPLC-PDA) method. Among the plant parts, the trend of accumulation of total phenols and flavonoids was as follows: roots > flowers > stems > leaves in both populations. It has been observed that Kalkati Dhar germplasm has the highest phenolic content in the roots (16.42 ± 0.12 mg g−1 DW), while accession collected from Renugaad has the highest flavonoid content in the flowers (4.34 ± 0.024 mg g−1 DW). Eight bioactive compounds (caffeic acid, resorcinol, p-coumaric acid, ferulic acid, veratric acid, myristicin, coumarin, and quercetin) were found dominant in the Kalkati Dhar germplasm (3200 m asl, high altitude). Significantly, seven compounds, viz; vanillic acid, vanillin, cinnamic acid, epicatechin, catechol, luteolin, and rutin, were found predominate in the Renugaad germplasm (2750 m asl, low altitude). Overall, root part accumulates most of the bioactive polyphenolic compounds as compared to the aerial parts; therefore, it has the highest antioxidant potential.