Native Australian fruits - a novel source of antioxidants for food

Abstract Twelve native Australian fruits, finger lime (red and yellow), riberry, brush cherry, Cedar Bay cherry, muntries, Illawarra plum, Burdekin plum, Davidson's plum, Kakadu plum, Molucca raspberry and Tasmanian Pepper, were investigated for their antioxidant capacity and presence of phenolic compounds, anthocyanins and ascorbic acid. The radical scavenging activities of five of the evaluated fruits were significantly higher (3.1 to 5.2-fold in the TEAC assay and 1.2 to 4.2-fold in the PCL assay, respectively) than that of the control blueberry, cv. Biloxi. The total phenolics level (Folin–Ciocalteu assay) in six of the twelve fruits was 2.5 to 3.9-fold of that of blueberry. Kakadu plum was identified as the richest source of ascorbic acid (938-fold of that of control). A high correlation between total phenolics (but not anthocyanins) and antioxidant capacity was observed. The HPLC-DAD/ESI/MS-MS profiles revealed simple anthocyanin composition (one to four individual pigments) with cyanidin as the dominating type. Australian native fruits investigated in this study are shown to be a novel rich source of antioxidant compounds. Industrial relevance The search for world unique food ingredients and flavors with enhanced health-beneficial properties is at present one of the key market trends. Botanicals from the regions linked to wellness and natural functionality with exotic fruits called “superfruits”, such as acai from Amazonia, are becoming a popular target of health-conscious consumers and industry managers. Sustainability and responsibility for the environment is another important reason which brings a commitment to ethical products. Utilization of local and seasonal fruits will not only enhance the variety of exotic fruits available on international market, but will contribute toward sustainable agriculture. Our research program addresses all these essential issues. In this manuscript we are describing for the first time twelve native Australian fruits as a rich source of antioxidants. We propose these exotic fruits to be considered as a potential source of bioactive phytochemicals for application in health promoting foods.