Black sesame pigment extract from sesame dregs by subcritical CO ce:inf loc='post'>2/ce:inf>: Extraction optimization, composition analysis, binding copper and antioxidant protection

摘要

Black sesame pigment (BSP) is a natural product with good bioactivity. The massive accumulation of sesame dregs (SDs) from sesame seed processing provides a rich source of BSP. This study investigates the activity of BSP derived from SDs. A BSP yield of 3.58?±?0.08% was achieved via extraction with subcritical CO2under optimal conditions. BSP effectively bound Cu in vitro at a pH of 7.0 (R?>?90%). Furthermore, binding activity was observed inSaccharomyces cerevisiae(43.78% reduction in intracellular Cu, BSP at 200?μg/mL). In addition, BSP conferred antioxidant protection in mutant yeast strains lacking superoxide dismutase and glutathione synthase by decreasing lipid peroxidation and reactive oxygen species (ROS). Superoxide dismutase and glutathione synthase protect against ROS by decreasing lipid peroxidation conferred by BSP. For decreasing intracellular ROS, only glutathione synthase seemed to be involved.