Comparison of the antioxidant activity of Echium amoenum Fisch and C.A. Mey, Chamaemelum nobile (L.) All and Camellia sinensis (L.) O. Kuntze on oleic acid photooxidation using water soluble porphyrin complexes as catalyst

Lipid photooxidation is the undesirable chemical process in which singlet oxygen result in the peroxidation of fatty acids. In this study leaves aqueous extract of Camellia sinensis (L.) O. Kuntze and flower extracts of Chamaemelum nobile (L.) All and Echium amoenum Fisch and C.A. Mey collected from natural habitats in Lahijan, Shiraz and Golestan National Park, respectively. Aqueous extracts were extracted using maceration method. Generation of singlet oxygen and peroxide products in the presence of H2TCPP (meso-tetra-carboxy phenyl porphyrin) were proved by 1H NMR spectroscopy, UV-Vis spectroscopy and iodometric titration method. Aqueous extract of Echium amoenum Fisch and C.A. Mey flowers, aqueous extract of Camellia sinensis (L.) O. Kuntze leaves, aqueous extract of Chamaemelum nobile (L.) flowers and Ascorbic acid as a chemical antioxidant indicated an inhibition of 42.75%, 38.34%, 36.98%, 33.51% and 20.32% on peroxidation of oleic acid, respectively. The results of this study also showed that the antioxidant activity of Echium amoenum Fisch and C.A. Mey in organic solvents such as acetonitrile, ethanol and methanol solvents are maintained.