The Influence of in Vitro Gastrointestinal Digestion of Brassica oleracea Florets on the Antioxidant Activity and Chlorophyll, Carotenoid and Phenolic Content

Brassica oleracea L. var. Italica is known to contain a wide variety of antioxidants and due to the protection against various diseases its consumption has been increasing over the years. Thus, knowledge of the changes that occur during the digestion process is of great interest. The aim of this study was to investigate the influence of in vitro gastrointestinal digestion of broccoli on antioxidant activity and on the chlorophyll, carotenoid and phenolic content. First, the ultrasound-assisted extraction of bioactive compounds was optimized and the kinetic model was evaluated. Then, the broccoli was subjected to a static simulated digestion. The antioxidant activity was monitored by ABTS [2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonate)] assay and the contents of target compounds were investigated by UV-Vis spectrophotometry and thin-layer chromatography. The optimum conditions were: solvent—ethanol; time—20 min and temperature—30 °C, and a second order kinetic model was found to describe the mechanism of extraction. The antioxidant activity and carotenoid, chlorophyll and total phenolic content was significantly decreased after simulated gastric and intestinal digestion. The gastric digestion considerably decreased carotenoid and chlorophyll content, meanwhile the intestinal digestion significantly decreased the total phenolic content (TPC). The antioxidant activity was equally affected by both gastric and intestinal digestion

Sweeteners from Different Lingonberry Jams Influence on Bioaccessibility of Vitamin C, Anthocyanins and Antioxidant Capacity under In Vitro Gastrointestinal Digestion

Lingonberries are considered anot fully exploited major source of antioxidants. Their health benefits are closely linked to their bioavailability. Due to growing health concerns, consumers are looking for jams prepared with sweeteners other than white sugar, which could be a good alternative to meet their needs. The aim of this research was to evaluate the influence of sucrose, fructose, erythritol, brown sugar, coconut sugar, stevia and saccharine on the bioaccessibility of vitamin C, anthocyanins andthe antioxidant capacity of lingonberry jams under in vitro gastrointestinal digestion. The vitamin C, total anthocyanin content and antioxidant capacity measured by ABTS and FRAP assays were determined spectrophotometrically. Individual anthocyanins were determined by high performance liquid chromatography. All analyzed compounds were highly altered during gastrointestinal digestion and this effect was more visible in the case of the anthocyanins. Antioxidant capacity decreased after gastric digestion, but after the gastrointestinal step, radical scavenging capacity increased, while reducing power decreased. Vitamin C bioaccessibility was negatively affected by coconut sugar addition, while stevia addition showed a protective effect. Fructose and sucrose increased the total anthocyanin stability during the intestinal phase. Stevia, fructose and coconut sugar exhibited high protection of the antioxidant capacity of lingonberry jams during digestion