Purification of limonoid glucosyltransferase from navel orange albedo tissues

Abstract

Abstrae~UDP-D-glucose:limonoid glucosyltransferase was purified from albedo tissues of navel orange (Citrus sinensis) cultivars, Frost and Newhall, by a combination of (NH4)2SO 4 fractionation, UDP-glucuronic acid affinity chromatography and DEAE ion exchange HPLC. This procedure resulted in a 452-fold increase in enzyme purification. This enzyme catalysed the glucosylation of both nomilin and limonin. SDS-PAGE showed a M~ of 5(~58 k for the enzyme. The enzyme displayed a peak of activity between pH 6.5 and 9.0 with an optimum at 8.0. Mn 2+ stimulated enzyme activity by 66% over basal activity observed with EDTA. Activity was lost when the purified enzyme was frozen and stored in Tris-HC1 buffer at pH 8.0. Published by Elsevier Science Ltd INTRODUCTION

Purification and characterization of UDPG:ginsenoside Rd glucosyltransferase from suspended cells of Panax notoginseng

“…Many bioseparation techniques have been used for purification of glucosyltransferases involved in plant secondary metabolism, such as ammonium sulphate precipitation, ion exchange chromatography, affinity chromatography and gel filtration [19][20][21][22]. In our purification procedure of UGRdGT from P. notoginseng cells, ion exchange chromatography was found to be very effective.…”

Isolation and characterization of limonoate and nomilinoate A-ring lactones

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Limonoids in Seeds of Iyo Tangor (Citrus iyo hort. ex Tanaka)

“…The conversion of open D-ring limonoid aglycones to their corresponding glucosides is catalyzed by UDP-D-glucose transferase, which has been isolated from the navel orange tissue (Hasegawa et al, 1997). The glucosidation of aglycones in the seeds begins during the late stage of fruit growth and continues during maturation until the fruit is harvested .…”