Antioxidant and phytochemical analysis of volatile oil and extracts of Pinus wallichiana

The present study aims to explore the chemical constituents and antioxidant potential of Pinus wallichiana essential oil and extracts. Chemical composition of the essential oil was analyzed by GC-MS and result showed that the oil contain three major monoterpene compounds viz. α-pinene (48.6%), β-pinene (45.6%) and limonene (5.6%). Antioxidant potential of Pinus wallichiana was analyzed by three basic methods; DPPH radical scavenging method, FRAP assay and Fe2+ ion chelating activity. Among leaf and bark extracts, best radical scavenging, activity was determined by aqueous extract (IC50 values 20.83±0.8µg/ml) of bark followed by its methanol extract (IC50 value 25.9±1.6µg/ml). The aqueous extract of bark also exhibited better reducing and chelating activity than leaf extracts. Essential oil showed moderate radical scavenging and chelating activity but negligible reducing activity. Phytochemical analysis of extracts determined that the aqueous and methanol extracts of bark contain rich amount of poly phenol and flavonoids, in comparison to the leaf extracts. A significant correlation between the antioxidant activity and these phytoconstituents of the extracts has been observed. The results of the present study concluded that the bark of Pinus wallichiana is a potential source of active antioxidant constituents that could be further explored and exploited for numerous commercial applications.