UDPG: p-COUMARATE GLUCOSYLTRANSFERASE ACTIVITY IN ENZYME EXTRACTS FROM HIGHER PLANTS

Article abstract of DOI:10.1016/0031-9422(81)83008-7

Leaves of Coleus, Pilea, Cistus and Cestrum, and ripe tomatoes were all able to convert trans-cinnamic acid-<3-14C> into glucose esters of cinnamic acids.The pool sizes of these esters were measured by the radioisotopic dilution method, and they were found to be of the order of a few μg/g fresh plant material. 1-O-Caffeoyl-β-D-glucose in Cestrum leaves amounted to 70 μg/g fresh plant material.Enzyme extracts from Cestrum leaves were able to convert trans-p-coumaric acid-<3-14C> to 1-O-p-coumaroyl-β-D-glucose, using UDPG as a source of glucose.This enzyme activity could be measured only by trapping techniques, due to the presence of considerable hydrolase activity in crude enzyme extracts.Key Word Index- Coleus; Labiatae; Cestrum; Lycopersicon; Solanaceae; UDPG; p-coumarate glucosyltransferase; hydroxycinnamic acids; biosynthesis.