Phytochemical composition and antioxidant capacity in Mexican pecan nut

The nut is a very nutritious fruit, and they play an important role in the nutrition of humans, because it is an important source of antioxidants and natural phenol compounds. It has been shown that such compounds are able to reducing the risk to get chronic diseases. This study evaluates the content in phenolic compounds and the antioxidant activity in pecan edible part 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.sup.-1]) and tannins (582.07 mg [g.sup.-1]) found in the shell were 7- to 8-fold higher than in the edible part. The results for the variety Wichita were significantly higher than for Western. The antioxidant activity was assessed by the DPPH*method (1,1-diphenyl-1,2-picrylhydrazyl), which correlated strongly with the phenolic compounds ([r.sup.2] = 0.99). Using liquid chromatography (HPLC) three phenolic compounds could be identified in the edible part and shell of the pecan nut, which were, 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 edible part and the shell. These compounds are of great importance for the health of the people. The high concentration of phytochemicals in the shells represents a good source of antioxidants for future applications in the pharmaceutical and agro-food industry.