Identification of Bioactive Phytoconstituents in Rheum Emodi via Gas Chromatography-Mass Spectrometry

Abstract

Rheum emodi Wall. (Polygonaceae), an important Himalayan medicinal herb, is traditionally valued for treating liver disorders, gastrointestinal problems, infections, inflammation, and other ailments. The present study investigated the phytochemical composition of R. emodi collected from the Siran Valley, Pakistan, with emphasis on comparing the rhizome (conventionally used part) with fruits, leaves, and callus. Methanolic extracts (2 g/250 mL) of each plant part were prepared using Soxhlet extraction and subjected to preliminary qualitative phytochemical screening. The chemical profiling was further performed through Gas Chromatography–Mass Spectrometry (GC–MS) using an Rxi®-5Sil MS capillary column, and compounds were tentatively identified by matching mass spectra with NIST and Wiley libraries. Phytochemical screening showed the widest metabolite diversity in rhizomes, including anthraquinones, while leaves and fruits showed strong presence of phenolics/tannins and flavonoids. GC–MS analysis revealed distinct organ-wise fingerprints; the rhizome was dominated by the anthraquinone chrysophanol (43.97% peak area) along with physcion, whereas leaves were enriched with fatty acid methyl esters and antioxidant-associated constituents such as squalene and vitamin E. Callus exhibited a comparatively reduced profile, indicating altered metabolite accumulation under in vitro conditions. These findings provide baseline chemical evidence supporting traditional use and highlight potential bioactive value in non-rhizome tissues.