Acylation of flavonoid glycosides enhances their chemical stability, lipo-solubility and antioxidant activity, improving their medicinal potential. Enzymatic acylation of flavonoid glycosides is advantageous compared to chemical procedures, as these reactions proceed at mild conditions and the acyl group is inserted at specific positions. In the present work, enriched leaf protein extracts of Croton floribundus Spreng and C. urucurana Baillon (Euphorbiaceae) were used as sources of enzymes in approaches to obtain p-coumaroyl derivatives of 3-O-glycosides of kaempferol and quercetin, as well as 7-O-quercetagetin glucoside. Tiliroside (1), helichrysoside (2) and quercetin-3-O-(6″-p-coumaroyl)-galactoside (3) were detected by HPLC–DAD and UPLC/MS as products of acylation reaction, using protein extracts of C. urucurana and either p-coumaroyl-CoA or p-coumaric acid plus CoA and ATP. Protein extracts of C. floribundus Spreng were effective toward the acylation of kaempferol-3-O-glucoside. Although acyltransferases seem to be ubiquitous in Croton, the ability to acylate different flavonol glycosides might largely depend on the species. Acyltransferases in the protein extracts are versatile at acylating flavonoids with distinct aglycones and distinct sugar substituents. The failure to attain acylated products of quercetagetin-7-O-glucoside indicates that Croton acyltransferases are regioselective, with a target on 3-O-sugars of flavonoids.

黄酮苷的酰化增强了它们的化学稳定性、脂溶性和抗氧化活性，从而提高了它们的药用潜力。与化学程序相比，类黄酮糖苷的酶促酰化是有利的，因为这些反应在温和的条件下进行，并且酰基插入在特定位置。在目前的工作中，富集的叶的蛋白质提取物巴豆floribundus林氏和C. urucurana Baillon（大戟科）用作酶的来源的方法，以获得对- 3-香豆衍生物ö山柰酚和槲皮素的-glycosides，以及7 - O-槲皮素葡萄糖苷。Tiliroside (1), 蜡菊苷 (2) 和槲皮素-3- O- (6″-对香豆酰)-半乳糖苷 (3) 通过 HPLC-DAD 和 UPLC/MS 检测为酰化反应的产物，使用C. urucurana和对香豆酰辅酶 A 或对香豆酸加辅酶 A 和 ATP 的蛋白质提取物。C. floribundus Spreng 的蛋白质提取物对山奈酚-3- O-葡萄糖苷的酰化有效。尽管酰基转移酶似乎在巴豆中无处不在，但酰化不同黄酮醇糖苷的能力可能在很大程度上取决于物种。蛋白质提取物中的酰基转移酶可用于酰化具有不同苷元和不同糖取代基的黄酮类化合物。槲皮素-7- O酰化产物未能获得-glucoside 表明巴豆酰基转移酶具有区域选择性，目标是黄酮类化合物的3- O-糖。