Enzymatic Synthesis of a Novel Kaempferol-3-O-β-d-glucopyranosyl-(1→4)-O-α-d-glucopyranoside Using Cyclodextrin Glucanotransferase and Its Inhibitory Effects on Aldose Reductase, Inflammation, and Oxidative Stress

Abstract

Kaempferol-3-O-β-d-glucopyranoside (astragalin, AS), a major flavonoid that exists in various plants, exerts antioxidant, antitumor, anti-human immunodeficiency virus (HIV), and anti-inflammatory effects. However, the low water solubility of AS limits its use. In this study, we used cyclodextrin glucanotransferase (CGTase) with maltose (G2) as a donor molecule to enzymatically modify AS to improve its water solubility and physiochemical properties. We isolated the glycosylated astragalin (G1-AS) and identified the structure of G1-AS as kaempferol-3-O-β-d-glucopyranosyl-(1→4)-O-α-d-glucopyranoside, where one glucose residue was transferred to AS. G1-AS retained the antioxidative activity of the original AS compound; however, the solubility of G1-AS was 65-fold higher than that of AS. In addition, G1-AS showed enhanced anti-inflammatory effects and aldose reductase inhibitory activity compared to AS when applied to rat lenses.

Enzymatic Synthesis of a Novel Pterostilbene α-Glucoside by the Combination of Cyclodextrin Glucanotransferase and Amyloglucosidase

“…(Toruzyme 3.0L) worked better than that from Bacillus macerans (CGTase Amano). The transglycosylation activity of CGTase is well reported, as it is able to glucosylate other phenolic compounds such as resveratrol [ 26 , 27 ], catechin [ 28 ], hydroquinone [ 29 ], kaempferol [ 30 ] or genistein [ 31 ].…”

Anti-glycation, Carbonyl Trapping and Anti-inflammatory Activities of Chrysin Derivatives

“…The low solubility of flavonoids restricts their application in medicine. Therefore, many researchers have sought new methods of modifying their structures to improve their physical and physiological activities [ 30 ]. In the present study, we synthesized 5,7- O -DA by simple O -acetylation using anhydrous acetic anhydride and significantly increased the water solubility of 5,7- O -DA (5,7- O -DA > 7- O -A > CS > 5,7- O -DM > 7- O -M> 7- O -P).…”

“…RAW 264.7 cells were seeded into 12-well plates at 4 × 10 5 -cells/well, and then incubated with LPS (1 μg/mL) and various concentrations of samples for 24 h. The concentration of nitric oxide (NO) in the medium was measured using the Griess reagent system, as described by the manufacturer. The production of NO was measured at 570 nm using an EL-800 Universal microplate reader (Bio-Tek Instrument Inc., Winooski, VT, USA), and was compared with a sodium nitrite standard calibration curve [ 30 ].…”

“…After sonication, undissolved samples were eliminated by centrifugation (7000× g , 37 °C, 5 min). The supernatants were diluted in methanol and filtered through a 0.45 μm disposable syringe filter (Advantec, Dublin, CA, USA) to analyze the concentration of the samples using HPLC analysis [ 30 ].…”

Optimization of Regioselective α-Glucosylation of Hesperetin Catalyzed by Cyclodextrin Glucanotransferase

“…(Toruzyme 3.0L) [ 30 , 33 ], employing partially hydrolyzed starch (maltodextrins with DP ≤ 60) as glucosyl donor. This enzyme has demonstrated an extraordinary ability to glucosylate other mono- and polyphenolic compounds [ 26 , 31 , 32 , 34 , 35 , 36 , 37 , 38 ].…”