From waste to wealth: A review of emerging approaches for utilizing dragon fruit (pitaya) waste polysaccharides in...

Dragon fruit production generates a substantial amount of agricultural waste, including peels, seeds, pulp residues, and foliage, which are often discarded despite their rich content of valuable bioactive compounds. Among these, polysaccharides are highly promising yet underexploited with diverse biological activities. This review comprehensively summarizes the types of polysaccharides found in dragon fruit waste, recent advancements in the extraction, purification, and functional evaluation of polysaccharides obtained from dragon fruit waste. These polysaccharides exhibit a wide range of biological activities, including strong antioxidant activity, anti-inflammatory effects, prebiotic properties beneficial for gut health, anti-diabetic and metabolic regulatory functions, wound healing promotion, and antibacterial actions. Because of the covalent combination of dragon fruit polysaccharide and betaine, it can effectively scavenge various free radicals, delay aging and cell damage, and make it have strong antioxidant capacity. On the contrary, the antioxidant capacity of ordinary fruit polysaccharides is limited, mainly relying on the synergistic effect of vitamin C, polyphenols and other components in fruits. What's more, the high-value applications of these polysaccharides across multiple sectors are also discussed, including their use as functional ingredients in the food industry, therapeutic agents in pharmaceutical and biomedical fields, active compounds in cosmetic and personal care formulations, and eco-friendly materials for environmental and agricultural applications. This review provides valuable insights and guidance for further research, development, and utilization of proposed to facilitate the full realization of dragon fruit waste polysaccharides as renewable resources for high-value applications.