Flavonolignans are natural phenols comprises flavonoid part and lignant part. Flavonolignans arise from oxidative coupling of 3-hydroxyflavonone taxifolin having amidst coniferyl alcohol. An imperative flavonolignans such as silymarin and silybin are formed by Silybrum marianum Gartn. These constituents enclose anti-hepatotoxic properties. Three flavonolignans acquired from flavone tricin are isolated from herb Avena sativa.