Chemical Characterization and Antioxidant Potential of the Rowan Fruits (Sorbus aucuparia L.) from Alpine-Dinaric region of Croatia

Abstract

Research background. The rowan (Sorbus aucuparia L.) is a small tree in the Rosaceae family with characteristic orange-red fruits. Raw fruits can be used for making jams, juices, and puree, as well as dried ones for teas. In folk medicine, they were used to prevent scurvy and bleeding or as a diuretic and laxative. The aim of this study was to characterize the proximate chemical composition, antioxidant potential, and macro and trace elements of the rowan fruits for their potential use as a functional food. Experimental approach. Fruits were collected in the Alpine-Dinaric region of Croatia in 12 populations. After collection, samples were transported to the laboratory, chopped into small pieces, placed in plastic containers, and stored at -20 ºC until analysis. Proximate chemical composition, including ash, water, cellulose, crude fat, crude protein, was determined according to the official AOAC methods and total carbohydrates as non-structural carbohydrates. Total phenolic content (TPC) and antioxidative capacity (TAC) were also measured. For multielement analysis, fruits were cleaned from the dust, lyophilized, homogenized, and acid digested in a microwave system. Concentrations of elements were quantified using the ICP-MS method. Results and conclusions. The basic constituents in analyzed fruits were 76.53 % of water, 17.45 % of total carbohydrates, 2.98 % of crude proteins, 1.49 % of crude fats, 1.07 % of cellulose, and 1.29 % of ash. On average, the TPC was 932 mg/100 g and the TAC was (60.14±14.48) % and (4.1±1.2) mmol Fe2+/100 g, determined by DPPH and FRAP assay, respectively. Levels of elements decreased as follows (in mg/kg): K: 2485 > Ca: 459 > P: 206, Mg: 193 > Na: 6.29 > Fe: 3.68, Mn: 3.58 > Zn: 1.11 > Cu: 0.731 > Mo: 0.098 > Co: 0.003 > Se: 0.001. In comparison with the literature, the phenolic and element content of the rowan fruits are similar to that of blueberry and raspberry. Obtained results suggest that the rowan fruits have valuable nutritional properties and could be useful for the fortification in the food industry. Novelty and scientific contribution. The importance of the obtained results is reflected in the completion of the literature gaps on the elemental composition, especially on the content of essential macro- and trace elements, as well as the antioxidant potential of rowan fruits.