Impact of simulated in vitro gastrointestinal digestion on the antioxidant activity and phenolic compounds of soursop peel (Annona muricata L.).

Abstract

Abstract This work aimed to investigate in vitro phenolics bioaccessibility and soursop peel's antioxidant activity. Proximate composition, ascorbic acid, total phenolic compounds, and in vitro antioxidant activity (DPPH, ABTS, and FRAP assays) were conducted on soursop peel and pulp. The accessibility of total phenolics and antioxidant capacity of soursop peel and pulp was assessed through simulated in vitro digestion. Soursop peel had a significant amount of fiber, particularly insoluble fiber, and higher levels of total phenolic compounds and antioxidant capacity than pulp. The pulp has 30% higher levels of ascorbic acid than the peel. Simulated in vitro digestion, the total phenolic compounds of the peel exhibited stability throughout the gastric and intestinal stages. In the pulp, there was an increase in total phenolic compounds that persisted until the final stage. After the simulation of in vitro digestion, the peel showed stability in DPPH antioxidant capacity analysis and obtained higher accessibility in the enteric II stages (40% and 29%) on ABTS and FRAP assays. Soursop pulp increased accessibility in the gastric stage on DPPH and FRAP assay. In the ABTS method of antioxidant capacity evaluation, the pulp showed the highest values in enteric phase II. These results are essential for human nutrition as they provide information about soursop peel and pulp's nutritional and bioactive composition. Furthermore, the in vitro accessibility of these compounds offers insights into their potential utilization by the organism. This knowledge holds significant implications for nutrition experts, as it can inform the development of healthier dietary habits and promote enhanced health outcomes.