A Critical Review on Tropical Fruits Seeds as Prospective Sources of Nutritional and Bioactive Compounds for Functional Foods Development: A Case of Indonesian Exotic Fruits

Some tropical countries in the Southeast Asia are rich in exotic fruits with worldwide acceptance, such as mango, orange, snake fruit, durian, jackfruit, rambutan, and avocado. In addition to their abundant production, those fruits are also currently gaining expansive distribution and marketing due to their promising advantages to human well-being. Surprisingly, their by-products, especially the seed kernel and peel, which account about 10–35% of their weight also offer high nutritional and functional potentials. This work exhibits the nutritional and bioactive compositions of the seeds of eight tropical exotic fruits, which are analyzed for their possible application as sources of functional food and environmental points of view. The seeds contain essential bioactive components, such as polyphenols, flavonoids, phenolic acid, and carotenoids, that exhibit excellent antioxidant activity, fats that have remarkable physicohemical properties (free of trans-fatty acids), and a high protein content. After a proper reduction of antinutritional contents, seed powders which contain carbohydrate, protein, and premium lipids or specific extracts with excellent functional properties can be obtained. However, further research should be carried out to determine the profiles of the nutritional and bioactive components in different seed types, their bioavailability, and their efficacy. Extensive researches with the industrial parts should also be performed to valorize the nutritional and functional potentials of these exotic fruit seeds.