Formation of Metal‐Chlorophyll Derivatives Extract From Chaetomorpha aerea Algae and Comparison of Their Antioxidant Activity

Chlorophyll pigment has attracted increasing interest due to its applications in cosmetics, medicine and the food industry, largely owing to its antioxidant properties and characteristic green colour. However, natural chlorophyll is inherently unstable and highly susceptible to degradation when exposed to heat, acidic conditions or light. This instability limits its practical use in many industrial applications. This study is aimed at forming metal‐chlorophyll derivatives from chlorophyll extracted from Chaetomorpha aerea algae with the aim of enhancing the antioxidant activity of chlorophyll. The effects of metal ion type, metal ion concentration, pH and incubation time on the efficiency of metal‐chlorophyll derivatives formation were investigated. The results showed that Cu‐chlorophyll (Cu‐Chl) derivative was formed with Cu 2+ ions (CuSO 4 ) at a concentration of 150 ppm, under pH 6 for 90 min of incubation, exhibiting the highest antioxidant activity as compared with native chlorophyll extracted from C. aerea algae. The results highlight the potential application of Cu‐Chl derivatives in cosmetics or functional foods.