Gene Expression and Enzyme Kinetics of Polyphenol Oxidases in Strawberry and Their Possible Involvement in Enzymatic Browning Reactions in Strawberry Nectar.

ABSTRACT: The browning of fruit juices and nectars is a common issue in the beverage industry and is a particular problem in strawberry nectars, where it significantly reduces the shelf-life. Polyphenol oxidases (PPOs), which are multicopper enzymes responsible for the oxidation of a wide plethora of polyphenols in plants, have been widely assumed to be involved in the enzymatic browning of strawberry nectar. To investigate the possible involvement of PPOs, the substrate specificity of four recombinant PPOs and their gene expression pattern in 10 cultivars of Fragaria × ananassa at five ripening stages were determined. This allowed us to obtain adequate amounts of enzymes to study them independently and without interfering matrix effects. All four PPOs possess monophenolase activity, w

SUBMITTER: Zavarise A 

PROVIDER: S-EPMC12191596 | biostudies-literature | 2025 Jun

REPOSITORIES: biostudies-literature