Bioaccessibility of Phytochemicals, Amino Acids, Antioxidant Capacity, and Enzyme Inhibitory Activities of Hawthorn (Crataegus spp.) Fruits Following INFOGEST Simulated Gastrointestinal Digestion

Abstract

ABSTRACT Hawthorn (Crataegus spp.) fruits are recognized as rich sources of phenolic compounds with well‐documented antioxidant and carbohydrate‐hydrolyzing enzyme inhibitory properties. However, the potential biological relevance of these phytochemicals depends largely on their stability and in vitro bioaccessibility during gastrointestinal digestion rather than on their native composition alone. This study comprehensively evaluated the impact of the standardized International Network of Food digestion (INFOGEST) model on the bioaccessibility of phenolic compounds and the associated changes in antioxidant capacity, free amino acid composition, and α‐amylase and α‐glucosidase inhibitory activities, while also characterizing the mineral composition of three Crataegus species. Simulated gastrointestinal digestion significantly decreased the bioaccessible fractions of total phenolics and flavonoids, accompanied by pronounced reductions in 2,2‐azino‐bis‐3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS), ferric reducing antioxidant power (FRAP), and cupric ion reducing antioxidant capacities (CUPRAC). Catechin was the predominant phenolic compound in all Crataegus species before digestion and remained the major phenolic in the bioaccessible fraction despite a substantial decrease during simulated gastrointestinal digestion. Although digestion attenuated the inhibitory activities against α‐amylase and α‐glucosidase, all hawthorn species retained appreciable enzyme inhibitory capacity following the intestinal phase. In parallel, l‐arginine, l‐glutamic acid, and l‐asparagine remained the predominant free amino acids in the bioaccessible fraction following simulated gastrointestinal digestion. In addition, distinct species‐dependent differences were observed in the mineral composition of the investigated hawthorn species. Collectively, these results demonstrate that simulated gastrointestinal digestion substantially influences the bioaccessibility of hawthorn phytochemicals and modulates their measured biological activities, whereas the investigated Crataegus species also differed in their nutritional composition. Overall, this study advances current understanding of the digestive stability and in vitro bioaccessibility of hawthorn phytochemicals and provides a scientific basis for selecting Crataegus species with favorable nutritional and functional attributes for future functional food development.