Nutritional Composition and Geographic Variation of Elaeagnus angustifolia Fruit from the Alxa Region, China

The nutritional composition of Elaeagnus angustifolia fruits from the Alxa Region, China, remains poorly understood. To address this gap, E. angustifolia fruits were collected from four sites (Tonggunaoer, Barunbieli, Chaertan, Jilantai) in the Alxa Region, Inner Mongolia. Morphological traits, basic nutrients (protein, fat, soluble sugar, titratable acid, crude fiber), mineral elements (Ca, Mg, Fe, Zn, Cu, Mn), and bioactive compounds (tannin, total flavonoids) were analyzed using standard methods. Significant geographic variation was observed. Chaertan fruits were the smallest (0.42 g), while Jilantai had the highest protein (7.49%). Barunbieli had the highest Ca (1721.20 μg/g), Fe (36.31 μg/g), and Zn (4.38 μg/g). Correlation analysis revealed a trade-off between organic nutrients and mineral elements (particularly Mg, Ca, Mn, and Cu) in larger fruits, and principal component analysis (PCA) explained 72.59% of the total variance. These preliminary findings provide a basis for germplasm conservation and functional food development of E. angustifolia.