Evaluation of the total antioxidant capacity and antioxidant compounds of different solvent extracts of Chilgoza pine nuts (Pinus gerardiana)

•The antioxidant potential of Pinus gerardania, or Chilgoza, was explored.•Six solvent extracts were prepared for comparison of antioxidant compounds.•Water and dichloromethane were observed to be the best solvents.•Polyphenols, xanthenes, carotenoids and tocopherols were present in all extracts. The total antioxidant capacity of Pinus gerardania, or Chilgoza and the presence of antioxidant compounds which typically exist in pine nuts were quantified. Oxygen radical absorbance capacity assay, ferric reducing antioxidant power, and the 2, 2-diphenyl-1-picrylhydrazyl (DPPH•) and 2, 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+) radical cation scavenging assays were conducted on dichloromethane, ethanol, ethyl acetate, hexane, methanol and water extracts of Chilgoza. The water and dichloromethane extracts displayed the highest antioxidant activity across all assays. Antioxidant compounds such as gallocatechin, catechin, lutein, lycopene, caretenoids and tocopherols were present in all extracts. Gallocatechin had the highest presence out of all the compounds. Its amounts present in the water and dichloromethane extracts were 64.9 and 56.9 µg per gram fresh weight (µg/g), respectively. The total carotenoid contents in the water and dichloromethane extracts were 14.72 and 14.26 µg/g, respectively, while the total tocopherol contents were 1.05 and 2.53 µg/g, respectively.