PREPARATION OF COMPLEXES OF SOME PHENOLIC ANTIOXIDANTS WITH CYCLODEXTRIN AND AMYLOSE

Abstract

Using antioxidants such as vitamin E and anthocyanins as food additives or in pharmaceutical applications is very important due to their strong antioxidant activity and protection activities against many of diseases. However, their usage is limited because of their high sensitivity towards heat, pH, light and UV radiation. Therefore, to enhance their stability, they were complexed with natural hosts i.e. β-cyclodextrin and starch that are available and non-toxic. In addition, these hosts have specific structure which is hydrophilic in outer surface and hydrophobic in inner surface; thus, they are suitable to form complexes with many guest molecules to modify their physicochemical properties. The purpose of this research was to prepare complexes of vitamin E in the form of α-Tocopheryl acetate and α-Tocopherol as well as strawberry anthocyanins with β-cyclodextrin and starch to enhance their stability against hydrogen peroxide and exposure to light and UV radiation. The obtained results can be summarized as follows: 1- Extraction of anthocyanins from strawberry by 0.1% HCl in methanol. 2- Preparation of six complexes of α-TQA, α-TQ and strawberry anthocyanins with β–cyclodextrin and starch as hosts. 3- Identification of the prepared complexes by spectroscopic analysis (UV-VIS and IR) and thermal analysis (TG, DTG and DSC). 4- Determination of stability of complexes against hydrogen peroxide. Results revealed that the both α-TQA and α-TQ complexes of β–CD and starch were more stable than un-complexed compounds in either oil or solution forms. AN complexes showed also more stability against H2O2 than AN powder or solution.