Effect of Roasting Levels and Drying Process of Coffea canephora on the Quality of Bioactive Compounds and Cytotoxicity

Coffee is a popular drink consumed all over the world. Besides its long-recognized stimulant effect, it has important nutritional and health effects. However, the type of bean processing modifies the composition of brewed coffee and possibly its bioactivity. In this study, extracts obtained from green and roasted beans of Coffea canephora (Coffea canephora var. robusta) were submitted to spray- or freeze-drying and were tested for antiproliferative activity, using MTT assay, and their influence on the cell cycle and apoptosis by flow cytometry analysis. Moreover, colors and nutrient contents were measured to identify the changes due to the roasting process. The results obtained showed that extracts from green and light roasted beans exhibited strong bioactive capacity. Coffee extracts promoted a decrease in cell viability, modulated cell cycle and induced apoptosis in human prostate carcinoma cell line (DU-145). The level of roasting reduced this property, but the type of drying did not in all cases.