Entrapment Of Curcumin To BSA/carrageenan Electrostatic Complexes

This work studied the influence of formation of BSA/t-carrageenan electrostatic complexes on the binding, stability and antioxidant activity of curcumin. BSA molecules and carrageenan molecules can form soluble BSA/carrageenan complexes through electrostatic interaction between positively charged amino groups on BSA molecule and negatively charged sulfated groups on carrageenan sugar chain. Studies have been employed to compare free curcumin, curcumin combined with BSA and curcumin combined with BSA/carrageenan complexes on curcumin UV and fluorescence spectra, determining curcumin properties, including binding constants of curcumin, degradation kinetics in neutral solution, curcumin stability and antioxidation. In the presence of BSA and i-carrageenan, curcumin gives higher intensities of absorption and fluorescence than free curcumin and curcumin combined with BSA. The determined values of the binding constant are higher for curcumin with BSAA-carrageenan complexes than curcumin with BSA alone. BSAA-carrageenan complexes are found to be superior to single BSA on enhancing stability and anti-oxide ability of curcumin. Besides, the added i-carrageenan is observed to restain curcumin in quenching intrinsic fluorescence of BSA. Moreover, changing the carrageenan types is found to be able to form soluble BSA/carrageenan complexes and decrease pKa of curcumin, achieving entrapment of curcumin.