Nutritional, Phytochemical, and Antioxidant Properties, and α-Amylase Inhibitory Activity of Pulp and Whole Fruit of Three Varieties of Christophine Fruits (Sechium edule, Curcubitaceae)

Sechium edule is a highly nutritious fruit used in many countries for therapeutic purposes. It is a rich source of bioactive compounds but is still mainly used for animal feed. The aim of this study was to evaluate the nutritional, phytochemical, antioxidant properties, and α-amylase inhibitory activity of the pulp and whole fruit of 3 varieties (spiny green, spineless green, yellow) of Sechium edule fruits. The protein (12.02%) and cellulose (2.01%) contents are high in the pulp of the spiny green variety and the whole fruit of the spineless green variety, respectively. Phenol and flavonoid contents were higher in the pulp of spiny green variety, 90.80 mg of GAE/g of E and 13.73 mg of EC/g of E, respectively, as were condensed and hydrolyzable tannin contents, 1.59 and 1.68 mg of TA/100 g, respectively. The pulp of the yellow variety showed the lowest values in oxalates, cyanides, and phytates. Antioxidant potential (FRAP) was a higher value in the pulp of the spiny green variety. The lowest IC50 values of the DPPH test and α-amylase inhibition test were 128.70 μg/mL in the whole fruit of the spiny green variety and 34.40 μg/mL in the whole fruit of the yellow variety, respectively. In conclusion, these results show that the green spiny variety of Sechium edule fruit has the best phytochemical and nutritional properties, making it the most suitable variety as a functional food, but it could also be used to prevent diabetes or regulate the glycemic index.