November 19, 2025 | Journal of the Science of Food and Agriculture | Mertoglu
This study conducted by Gottfried Wilhelm Leibniz University Hannover, Germany investigated the physicochemical characteristics and antioxidant properties of two commercially important pitaya species, the white-fleshed Hylocereus undatus and the red-fleshed Hylocereus polyrhizus. As climate change increases pressure on agricultural water resources, drought-tolerant crops such as cacti are receiving growing attention. Pitaya is particularly valued for its nutritional quality and antioxidant compounds, but the relationship between fruit composition and antioxidant function remains incompletely understood.
The researchers compared fruit size, soluble solids, organic acids, phenolic compounds, flavonoids, and antioxidant activity between the two species. White-fleshed pitaya produced larger and heavier fruits, whereas red-fleshed pitaya contained substantially higher levels of soluble solids, total phenolics, total flavonoids, and antioxidant activity. Correlation analyses indicated that increased sugar accumulation was associated with higher concentrations of phenolic compounds, contributing to stronger antioxidant capacity in the red-fleshed fruit.
Principal component analysis clearly distinguished the two species based on fruit size and biochemical composition. In addition, molecular docking analyses suggested that major organic acids and phenolic compounds could interact with the human iron regulatory protein IRP1, providing insight into possible antioxidant mechanisms.
The findings indicate that H. polyrhizus is a richer source of antioxidant compounds, while H. undatus offers superior fruit size and yield-related traits. The study provides useful information for breeding, climate-resilient cultivation, and value-added utilization of pitaya.
