The black seeds of Nigella sativa which are called black cumin seeds (BCUSs) were subjected to many studies from researchers to elucidate their bioactive compounds. For decades, BCUSs have been used conventionally by natives of different countries in treating many diseases. The active ingredients of BCUSs were proved for their significant biological activities such as antiinflammatory, immunomodulatory, antidiabetic, antihypertensive, antineurodegenerative, and anticancer as well. The present chapter focuses on the most common anticancer active compounds tested and proved by the various studies, thymoquinone, alpha-hederin, thymol (THY), longifolene (LON), and carvacrol (COL).
