Co-Ingestion of Natal Plums ( Carissa macrocarpa ) and Marula Nuts ( Sclerocarya birrea ) in a Snack Bar and Its Effect on Phenolic Compounds and Bioactivities.

This study investigated the effect of co-ingesting Natal plums ( Carissa macrocarpa ) and Marula nuts ( Sclerocarya birrea ) on the bioaccessibility and uptake of anthocyanins, antioxidant capacity, and the ability to inhibit α-glucosidase. A Natal plum-Marula nut bar was made by mixing the raw nuts and the fruit pulp in a ratio 1:1 ( v / v ). The cyanidin-3- O -sambubioside (Cy-3-Sa) and cyanidin-3- O -glucoside content (Cy-3-G) were quantified using the ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS). Inclusion of Natal plum in the Marula nut bar increased the Cy-3-Sa, Cy-3-G content, antioxidants capacity and α-glucosidase inhibition compared to ingesting Marula nut separately at the internal phase. Adding Natal plum to the Marula nut bar increased bioaccessibility of Cy-3-Sa, Cy-3-G, quercetin, coumaric acid, syringic acid and ferulic acid to 80.2% and 71.9%, 98.7%, 95.2%, 51.9% and 89.3%, respectively, compared to ingesting the Natal plum fruit or nut separately.