Phytochemical profiling, total flavonoid, total phenolic content and in-vitro antioxidant evaluation of Citrus maxima extract

Abstract

Introduction and Aim: Citrus fruits are rich in polyphenolic compounds. The conventional medical system has utilized the fruit’s entire composition including the peel for its diverse biological functions. With this, the study aimed to assess and compare the phytochemical, in-vitro antioxidant analysis as well as polyphenol and flavonoid content of Citrus maxima juice, aqueous and ethanolic extracts of its pulp and peel. Materials and Methods: Qualitative phytochemical screening, total phenolic content and total flavonoid content and different in-vitro antioxidant assays like total antioxidant capacity (TAC), Ferric reducing antioxidant power assay (FRAP), 2,2-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging assay were carried out to evaluate the in-vitro antioxidant potential in the juice, aqueous and ethanolic extract of pulp and peel of C. maxima. Gas chromatography–Mass spectrometry (GC–MS) analysis was performed in the peel ethanolic extract to identify the compounds present. Results: Preliminary phytochemical analysis revealed the presence of triterpenoids and steroids, glycosides, alkaloids, flavonoids, carbohydrates and vitamin C in all the C. maxima crude extracts. Tannins were present only in pulp of ethanol extract and in both aqueous and ethanol extracts of peel. Resins were present in the juice and ethanol extract of pulp and peel. The total phenol and total flavonoid content was comparatively higher in ethanolic extracts of peel. All the extracts showed dose-dependent free radical scavenging activity. The reducing potential of the C.maxima extractives increased with the increase in its concentration. GC-MS analysis of ethanolic peel extract identified key constituents with pharmacological effects. The ethanolic peel extract showed good antioxidant activity and free radical scavenging activity when compared to other extracts. Conclusion: The results indicated that ethanolic peel extract of Citrus maxima revealed the highest presence of polyphenolic compounds, which are secondary plant metabolites with potential antioxidant activity.