SCREENING OF POLYPHENOL OXIDASE AND PEROXIDASE ENZYMES FROM BRINJAL (SOLANUM MELONGENA) WITH EMPHASIS ON INHIBITION BY ORGANIC (EDIBLE) INHIBITORS

Abstract

Background: Polyphenol oxidase (PPO) and Peroxidase (POD) enzymes produce dark color to vegetables by oxidizing phenolic
substrates with oxygen and thus converting the di-phenol into melanin pigments. Therefore, the enzymatic browning can be
overcome by utilizing antioxidants, commercial synthetic inhibitors and organic edible inhibitors. Findings: PPO and POD enzymes were extracted from Solanum melongena by 30% and 70% (NH4)2SO4 saturation followed by Gel chromatographic purification by
Sephadex G-300 Colum. The estimated molecular weight of PPO was found 100 kDa. The highest activity of the enzymes was measured at 50°C and above 50 °C, enzyme was deactivated. The enzyme showed temperature stability in the range of 30–70 °C. The optimum pH of PPO of Solanum melongena was determined as 7.2 showing stability in the range of 6.2–8.2. Diverse commercial synthetic compounds as well as organic edible compounds were used to inhibit the enzymatic activity in Solanum melongena. Conclusion: Coffee and cinnamon powder among edible organic compounds and acetic acid and ascorbic acid among synthetic compounds were