o-glycosylation

D-(+)-Xylose (Wood sugar) is an aldopentose - a monosaccharide containing five carbon atoms and an aldehyde functional group. It has chemical formula C5H10O5 and is 40% as sweet as sucrose. Xylose is also found in mucopolysaccharides of connective tissue and sometimes in the urine. Xylose is the first sugar added to serine or threonine residues during proteoglycan type O-glycosylation. Therefore xylose is involved in the biosythetic pathways of most anionic polysaccharides such as heparan sulphate and chondroitin sulphate. In medicine, xylose is used to test for malabsorption by administering a xylose solution to the patient after fasting. If xylose is detected in the blood and or urine within the next few hours, it has been absorbed by the intestines. Xylose is said to be one of eight sugars which are essential for human nutrition, the others being galactose, glucose, mannose, N-acetylglucosamine, N-acetylgalactosamine, fucose, and sialic acid. . Xylose in the urine is a biomarker for the consumption of apples and other fruits.

Caffeic acid 4-O-glucoside (Linocaffein), a glycosylation product of Caffeic acid, reverses Aβ25-35-induced axonal atrophy and induces axonal regeneration in mouse cortical neurons, and can be used in Alzheimer's disease research.

Chrysin 7-O-beta-gentiobioside (Chrysin 7-O-β-gentiobioside), a glycosylation product of Chrysin, is derived from Spartium junceum.