This thesis documents a research program in which Australian grown Danshen extracts and related bioactive compounds have been demonstrated to be effective in scavenging free radicals, namely ROS generation, in a cell free system and NADPH oxidase derived superoxide (O2-) generation in vascular tissue (rat aorta). Danshen extracts, both aqueous and ethanol, and their active compounds (Tanshinone IIA, Salvianolic Acid B and Danshensu) demonstrated anti-oxidant activity however findings exhibited stronger activity in a cell free system than in the aortic vascular tissue. |