Enzymatic Synthesis of Puerarin Glucosides Using Cyclodextrin Glucanotransferase with Enhanced Antiosteoporosis Activity

Abstract

Puerarin (PU) is the most abundant isoflavone from the root of Pueraria lobata and exhibits a broad range of pharmacological activities. However, poor water solubility and low bioavailability limit its use. Enzymatic transglycosylation is emerging as a new strategy to improve the pharmacodynamic and pharmacokinetic properties of natural products for drug development. In this study, three PU glucosides (PU-G, PU-2G, and PU-3G) were synthesized by using a cyclodextrin glucanotransferase from Bacillus licheniformis with PU as the acceptor and α-cyclodextrin as the sugar donor. The transglycosylation products were isolated and structurally identified by mass spectrometry and nuclear magnetic resonance. The water solubilities of PU-G, PU-2G, and PU-3G were 15.6, 100.9, and 179.1 times higher than that of PU, respectively. Moreover, the antiosteoporosis activities of these glucosides were tested, and PU-G was found to show much more potent antiosteoporosis activity as compared to the original PU.

Enzymatic Synthesis of Novel and Highly Soluble Puerarin Glucoside by Deinococcus geothermalis Amylosucrase

“…The results revealed significant absorption at 3273 cm −1 , representing the typical hydroxyl groups, and another at 1623.9 cm −1 , representing the typical carbonyl groups in compound (1) (Figure S3). The compound (1) characteristic 1 H and 13 S1. Compound (1) was thus confirmed to be puerarin-4 -O-α-glucoside (Table S1 and Figures S4-S10).…”

“…Figure 3 illustrates the biotransformation process of puerarin by DgAS. Previously studied GH enzymes catalyzed two major glycosylations-α-(1→6 )puerarin and α-(1→4 )-puerarin-on the C-glucoside residue of puerarin [9][10][11][12][13][14][15][16][17]. In contrast, DgAS preferred catalyzing glycosylation on the 4 -hydroxyl group of puerarin and produced a novel derivative.…”

“…Ko et al, (2012) used Leuconostoc lactis dextransucrase (GH70; EC 2.4.1.5) to produce glucosyl-α-(1→6 )-puerarin and maltosyl-α-(1→6 )-puerarin, which possessed 15-fold and 202-fold higher solubility than that of puerarin, respectively [12]. Huang et al, (2020) used another GH13 enzyme, Bacillus licheniformis cyclodextrin glucanotransferase (EC 2.4. 1.19), to produce glucosyl-α-(1→4 )-puerarin, maltosyl-α-(1→4 )-puerarin, and maltotriosyl-α-(1→4 )-puerarin, which showed 15-fold, 100-fold, and 179-fold higher solubility than that of puerarin, respectively [13].…”

“…Huang et al, (2020) used another GH13 enzyme, Bacillus licheniformis cyclodextrin glucanotransferase (EC 2.4. 1.19), to produce glucosyl-α-(1→4 )-puerarin, maltosyl-α-(1→4 )-puerarin, and maltotriosyl-α-(1→4 )-puerarin, which showed 15-fold, 100-fold, and 179-fold higher solubility than that of puerarin, respectively [13]. On the other hand, Wang et al, (2014) and Wu et al, (2013) used Arthrobacter nicotianae β-fructosidase (GH32; EC 3.2.1.153) to produce fructosyl-β-(2→6 )-puerarin and difructosyl-β-(2→6 )puerarin [14,15], although the authors did not determine the solubility of the two puerarin fructosides.…”

Separation and purification of plant terpenoids from biotransformation

“…Structural modification is an effective tool for changing the lipophilicity and hydrophilicity of terpenoids and their saponins. For the desired modification, glycosylation acts as an important modification strategy to improve the druggability by increasing their solubility and bioavailability [14, 15]. Glycyrrhizin (GL), a major class of terpenoids found in licorice with immuno‐regulatory, anti‐oxidative, contains two molecules of glucuronic acid (GlcA) at 3‐OH of skeleton of glycyrrhetinic acid (GA).…”