Extraction of peroxidase enzyme from cabbage legs for catalytic biodegradation of textile dyes and bisphenol A in wastewater: Purification and characterization technologies

Abstract

Abstract In this work, the peroxidase enzyme was extracted from cabbage legs obtained from restaurant waste. Additionally, a comparison was made between crude and pure enzymes to evaluate their efficacy as catalysts for the biodegradation of common contaminants, textile dyes, and bisphenol A. The concentration of protein, bioactivity of peroxidase, and specific activity of both crude and pure enzymes were experimentally determined. The extracted peroxidase enzyme displayed optimal bioactivity at pH 6 and a temperature of 40°C. Moreover, it exhibited good stability across a wide pH range (3–7), retaining 65% of its original bioactivity at 60°C. The addition of FeSO4 and ZnCl2 enhanced enzyme activity by 153% and 120%, respectively, whereas exposure to CuCl2, AgNo3, and HgCl2 ions reduced enzyme activity by 60%, 53%, and 25%, respectively. The crude enzyme exhibited remarkable efficiency in decolorizing the synthetic dyes, with percentage decolorization of 86% and 78% for reactive blue 49 (RB) and reactive green 19 (RG), respectively, after a 10-hour incubation at the laboratory scale. Similarly, the pure enzyme exhibited a decolorization percentage of 79% and 75% for RB and RG, respectively, under the same conditions. The crude enzyme showed a high degradation efficiency of 92.8% for bisphenol A degradation in aqueous solution after 5 h.