Stable Polyphenol Oxidase Produced by Pleurotus pulmonarius from Fermented Peach-Palm and Cocoa Wastes

• Published in: Bioenergy research 2024-03, Vol.17 (1), p.198-207
• Main Authors: de Carvalho, Lucas Ribeiro, Santos, Débora Reis, dos Santos Lima, Camilla Silveira, Peralta, Rosane Marina, de Souza, Cristina Giatti Marques, Uetanabaro, Ana Paula Trovatti, da Silva, Erik Galvão Paranhos, da Costa, Andréa Miura
• Format: Article
• Language: English
• Subjects: Aluminum; Ammonium; Ammonium sulfate; Biomedical and Life Sciences; Biotechnology; Catechol; Cocoa; Cocoa beans; Economic importance; Enzymes; Ethylenediaminetetraacetic acids; Fermentation; Ions; Life Sciences; Magnesium; Phenolic compounds; Phenols; Plant Breeding/Biotechnology; Plant Ecology; Plant Genetics and Genomics; Plant Sciences; Pleurotus pulmonarius; Polyphenol oxidase; Reagents; Solid state fermentation; Substrates; Thermal stability; Wood Science & Technology
• ISSN: 1939-1242; 1939-1234; 1939-1242
• DOI: 10.1007/s12155-023-10628-0

Pleurotus pulmonarius is an economically important edible mushroom well known for the production of several lignocellulolytic enzymes, including polyphenol oxidase (PPO), EC 1.14.18.1. This enzyme can oxidize and hydrolyze phenolic compounds directly associated with the organoleptic and nutritional properties of foods. Thus, the aim of this paper is to produce and characterize the PPO of P. pulmonarius 21 (CCB21). The fungus was able to produce PPO using peach-palm waste and cocoa bean shell as substrates under solid-state fermentation (SSF) in 5 days of cultivation at 90% humidity (3066 ± 232 U/gds). PPO was partially purified with 60% ammonium sulfate and showed a purification rate of 2.1 times and a yield of 53.92%. The enzyme showed an optimum temperature above 45 °C, an optimum pH in the range of 5.5 to 6.5, and proved quite stable, maintaining 86–88% of its activity for up to 120 min under these conditions. PPO had reduced activity in the presence of β-mercaptoethanol, while EDTA, SDS, Al 3+ , Cu 4+ , Li 4+ , and Mg 2+ ions increased their activity. The enzyme presented a V max of 4166.65 U/min and a K m of 4.16 mM for pyrocatechol. The results obtained suggest that, due to its thermostability and little influence in the presence of ions and reagents tested, the PPO of P. pulmonarius CCB21 can be an alternative for application in different biotechnological and industrial processes.