Introduction
In recent years, natural extracts have been in high demand from the manufacturers of foods, cosmetics, and pharma- ceuticals due to the growing interest of consumers in ingredients from natural sources. Increasing concern about potentially harmful synthetic additives has also con- tributed to the demand. Synthetic antioxidants, such as butylated hydroxyanisole (BHA) and butlylated hydro- xytoluene (BHT), have restricted use in food because they have been reported to be carcinogenic. Some countries, such as Japan and some European countries, have not per- mitted the use of tertiary butyl hydroquinone (TBHQ), the most potent synthetic food antioxidant and other countries may ban it in the future. Therefore, the search for new natural antioxidant sources has been greatly intensified.1