L-Ascorbate oxidases

The specific enzyme, classified as EC 1.10.3.3, that converts L-ascorbic acid into dehydroascorbic acid while reducing molecular oxygen to water. Because it reacts selectively with the vitamin C form used in nutrition, it is the basis of precise enzymatic assays and biosensors that measure vitamin C levels in fruit juices, soft drinks, and fortified foods without interference from other reducing substances. Manufacturers use these measurements to verify label claims, check fortification dosing, and track nutrient losses through processing and storage. The enzyme also features in experimental antioxidant protection systems for food preservation, where oxygen-scavenging reactions extend shelf life. Heat destroys its activity, which is why blanching vegetables before freezing preserves their vitamin C. Recombinant versions now give laboratories a consistent, high-purity reagent.