Lgulonolactone

L-gulonolactone, also known as L-gulono-1,4-lactone, is a naturally occurring compound and a derivative of L-gulonic acid. It is a cyclic ester formed from L-gulonic acid, which is a sugar acid. In biological systems, L-gulonolactone is a key intermediate in the biosynthesis of L-ascorbic acid (vitamin C) in many animals.

The enzyme L-gulonolactone oxidase (GULO) catalyzes the final step in vitamin C synthesis by converting L-gulonolactone to L-ascorbic acid. Humans and some other species lack a functional GULO enzyme, making them unable to synthesize their own vitamin C and requiring dietary intake.

L-gulonolactone itself has been investigated for various biological activities. Some research suggests it may possess antioxidant properties. It has also been studied in the context of its potential role in cellular metabolism and as a precursor to other biologically relevant molecules. Its presence in various fruits and vegetables further highlights its natural occurrence.