An olive leaf extract (OLE) was microencapsulated with sodium alginate (SA) by spray-drying to study the evolution of oleuropein (ORP) during in vitro gastrointestinal digestion, and its bioaccessibility and potential bioavailability from OLE and OLE-SA microparticles. Secoiridoids, flavonoids, simple phenols, oleosides and elenolic acid were identified in OLE. OLE/SA ratio 1:1.6 and inlet air temperature 135 °C were the optimal conditions for OLE-SA microparticles. ORP (70%) from OLE was degraded during gastric digestion, giving hydroxytyrosol and ORP-aglycone, whereas only the superficial ORP was released from microparticles. The remaining ORP from OLE was degraded under intestinal conditions, leading to oleosides; whereas alginate was swollen and disintegrated, releasing the ORP (90% of encapsulated ORP). ORP from both OLE and microparticles was degraded to hydroxytyrosol under colonic conditions. Encapsulation of OLE allowed the protection of ORP under gastric conditions and its controlled release at intestinal conditions, and higher bioaccessibility (58%) and potential bioavailability (20%).

通过喷雾干燥将藻叶酸钠（SA）微囊化橄榄叶提取物（OLE），以研究橄榄苦苷（ORP）在体外的进化OLE和OLE-SA微粒的胃肠道消化及其生物可及性和潜在生物利用度。在OLE中鉴定了类胡萝卜素，类黄酮，简单的酚，油苷和亚油酸。OLE / SA比例为1：1.6，进气温度为135°C是OLE-SA微粒的最佳条件。OLE中的ORP（70％）在胃消化过程中被降解，产生了羟基酪醇和ORP-糖苷配基，而只有表面的ORP从微粒中释放出来。OLE中残留的ORP在肠道条件下被降解，形成了油苷。而藻酸盐溶胀并崩解，释放出ORP（占封装ORP的90％）。在结肠条件下，来自OLE和微粒的ORP被降解为羟基酪醇。