SINGLET OXYGEN CHEMISTRY .7. THE QUENCHING OF SINGLET OXYGEN BY THE MAIN ANTIOXIDATIVE COMPONENTS OF ROSEMARY

The quenching of singlet oxygen by rosmanol and carnosol is investigated by steady kinetic methods. The experiment offer the results of that the total rate constants k(A) for quenching singlet oxygen are 2.51 x 10(7) and 7.19 x 10(6) mol1.dm-3.s-1 in methanol respectively in which the chemical quenching rate constants K(r), are 1.27 x 10(7) and 9.82 x 10(5) mol.dm-3.s-1 and corresponding half quenching concentration beta values are 4.6 x 10(-3) and 1.6 x 10(-2)mol.dm-3 respectively. Two components extracted from natural rosemary appear excellent potential application as high performance antioxidative agents in food industries.