Phytochemical composition and antioxidant capacity in Mexican pecan nut

The nut plays a major role in human nutrition, as a nutritive food rich in phenolic compounds and natural antioxidants. These compounds have the ability to reduce the incidence of chronic diseases. This study evaluates the content in phenolic compounds and the antioxidant activity in pecan meat and shell, examining the two varieties Western and Wichita, cultivated in the region of Delicias of the state of Chihuahua (Mexico). The high concentrations of phenolic compounds (170.36 mg g-1) and tannins (582.07 mg g-1) found in the shell were 7- to 8-fold higher than in the meat. The results for the variety Wichita were significantly higher than for Western. The antioxidant activity was assessed by the DPPH (1,1-diphenyl-1,2-picrylhydrazyl), which correlated strongly with the phenolic compounds (r2=0.99). Three phenolic compounds were identified and quantified by high-performance liquid chromatography (HPLC) in the meat and the shell, i.e. gallic acid, ellagic acid, and catechin, while only ellagic acid was not identified in the shell of the variety Western. Pecans are rich in phytochemical compounds that provide high antioxidant activity to the meat and the shell. These phytochemical compounds are beneficial for human health. The high concentration of phytochemicals in the shells represent a good source of antioxidants for future applications in the pharmaceutical and agro-food industry.