Valorizing common pomelo peel by-product via a multi-dimensional framework: a functionally equivalent alternative to a rare botanical for liver health

Turning agricultural and food processing by-products into health-promoting ingredients is pivotal for developing sustainable food systems. This study developed an integrated multi-dimensional evaluation framework to assess whether the common pomelo peel by-product (Citrus grandis (L.) Osbeck, CGO) can serve as a functionally equivalent alternative to the rare Citrus grandis 'Tomentosa' (CGT) for functional food ingredient development. The framework combined comparative metabolomics and delayed luminescence profiling to characterize chemical and physical properties, alongside multi-parametric in vivo bioactivity and safety assessment in a diet-induced vertebrate model. Analyzes confirmed CGO and CGT as distinct chemotypes and physicotypes, with differential enrichment in bioactive pathways like phenylpropanoid biosynthesis. Crucially, both extracts demonstrated statistically equivalent efficacy in alleviating hepatic steatosis, oxidative stress, and inflammation in a high-cholesterol diet-induced zebrafish model, and modulated key genes related to lipid metabolism, antioxidant response, and inflammation. Safety assessment revealed CGO's significantly wider safety margin. Data integration across dimensions demonstrates that despite compositional differences, the net bioactivity converges on similar beneficial outcomes for liver metabolic health. This work provides a validated strategy for transforming underutilized residues into a multi-target, dietary-relevant ingredient, offering a replicable framework for resource-efficient development of sustainable functional crops and food supply chains.