The term "superfruit" has gained increasing usage and attention recently with the marketing strategy to promote the extraordinary health benefits of some exotic fruits, which may not have worldwide popularity. This has led to many studies with the identification and quantification of various groups of phytochemicals. This contribution discusses phytochemical compositions, antioxidant efficacies, and potential health benefits of the main superfruits such as açai, acerola, camu-camu, goji berry, jaboticaba, jambolão, maqui, noni, and pitanga. Novel product formulations, safety aspects, and future perspectives of these superfruits have also been covered. Research findings from the existing literature published within the last 10 years have been compiled and summarized. These superfruits having numerous phytochemicals (phenolic acids, flavonoids, proanthocyanidins, iridoids, coumarins, hydrolysable tannins, carotenoids, and anthocyanins) together with their corresponding antioxidant activities, have increasingly been utilized. Hence, these superfruits can be considered as a valuable source of functional foods due to the phytochemical compositions and their corresponding antioxidant activities. The phytochemicals from superfruits are bioaccessible and bioavailable in humans with promising health benefits. More well-designed human explorative studies are needed to validate the health benefits of these superfruits.
This article presents a comprehensive overview of upcycling commercial nut byproducts (such as Brazil nut, cashew, hazelnut, macadamia, peanut (also known as a legume), pecan, pine nut, pistachio, and walnut) for food, nutraceutical, and pharmaceutical applications. Upcycling nut byproducts, namely husk/hull, hard shell, brown skin, defatted flour/meal/cake, pine cone, cashew nut shell liquid, cashew apple, walnut septum, and dreg/okara, has great potential, not only to reduce/minimise waste, but also to fit within the circular economy concept. Each byproduct has its own unique functional properties, which can bring significant value. These byproducts can be used as value-added ingredients to promote better health and well-being, due to their rich sources of diverse bioactive components/phytochemicals, polysaccharides, fibre, lignin, prebiotics, oils, proteins, bioactive peptides, minerals, and vitamins, among other components. This comprehensive review provides a basis for future research and development of product applications for nut byproducts. More studies are needed on novel product development to valorise nut byproducts.
As many studies are exploring the association between ingestion of bioactive compounds and decreased risk of non-communicable diseases, the scientific community continues to show considerable interest in these compounds. In addition, as many non-nutrients with putative health benefits are reducing agents, hydrogen donors, singlet oxygen quenchers or metal chelators, measurement of antioxidant activity using in vitro assays has become very popular over recent decades. Measuring concentrations of total phenolics, flavonoids, and other compound (sub)classes using UV/Vis spectrophotometry offers a rapid chemical index, but chromatographic techniques are necessary to establish structure-activity. For bioactive purposes, in vivo models are required or, at the very least, methods that employ distinct mechanisms of action (i.e., single electron transfer, transition metal chelating ability, and hydrogen atom transfer). In this regard, better understanding and application of in vitro screening methods should help design of future research studies on 'bioactive compounds'.