16290-07-6

Usage

Uses

Used in Pharmaceutical Applications:
KAEMPFEROL-7-O-GLUCOSIDE is used as a therapeutic agent for its antioxidant and anti-inflammatory activities. These properties contribute to its potential use in treating various conditions, such as inflammation-related diseases and oxidative stress-related disorders.
Used in Cosmetic Applications:
KAEMPFEROL-7-O-GLUCOSIDE is used as an active ingredient in the cosmetic industry for its antioxidant and anti-inflammatory properties. It can be incorporated into skincare products to provide benefits such as reducing inflammation, protecting the skin from environmental stressors, and promoting overall skin health.

InChI:InChI=1/C21H20O11/c22-7-13-15(25)17(27)19(29)21(32-13)30-10-5-11(24)14-12(6-10)31-20(18(28)16(14)26)8-1-3-9(23)4-2-8/h1-6,13,15,17,19,21-25,27-29H,7H2/t13-,15-,17+,19-,21?/m1/s1

Upstream product

• 55136-76-0 kaempferol 3-O-sophoroside-7-O-β-D-glucopyranoside 
• 133-89-1 UDP-glucose 
• 520-18-3 kaempferol 
• 2106-10-7 1-deoxy-1-fluoro-α-D-glucose 
• 87863-90-9 3-O-β-sophorosyl-7-O-β-D-(2-O-feruloyl)glucosylkaempferol 
• 55136-76-0 kaempferol 3-O-β-D-[β-D-glucopyranosyl-(1→2)-glucopyranoside]-7-O-β-D-glucopyranoside 

Downstream Products

• 2280-44-6 D-Glucose 
• 520-18-3 kaempferol 

Relevant academic research and scientific papers

Identification of a flavonoid 7-O-glucosyltransferase from Andrographis paniculata

Andrographis paniculata is an important traditional medicinal herb in which flavonoids are part of the primary specialized metabolites. A flavonoid glucosyltransferase with broad substrate spectrum (named ApUGT3) was successfully identified by screening homologous glycosyltransferase genes from A. paniculata. The enzyme displayed glycosylation activity toward multiple flavonoids in?vitro, and the major products were identified as 7-O-glucosides. Phylogenetic analysis revealed that ApUGT3 is the first reported glycosyltransferase from the Acanthaceae family that belongs to cluster I, suggesting that ApUGT3 is a new flavonoid glycosyltransferase of this subcluster. This enzyme is potentially useful as powerful glycosylation catalysts to modify flavonoid-like compounds and improve their biological activities. (Figure presented.).

Characterization of flavonoid 7-O-glucosyltransferase from Arabidopsis thaliana

Most flavonoids found in plants exist as glycosides, and glycosylation status has a wide range of effects on flavonoid solubility, stability, and bioavailability. Glycosylation of flavonoids is mediated by Family 1 glycosyltransferases (UGTs), which use UDP-sugars, such as UDP-glucose, as the glycosyl donor. AtGT-2, a UGT from Arabidopsis thaliana, was cloned and expressed in Escherichia coli as a gluthatione S-transferase fusion protein. Several compounds, including flavonoids, were tested as potential substrates. HPLC analysis of the reaction products indicated that AtGT-2 transfers a glucose molecule into several different kinds of flavonoids, eriodictyol being the most effective substrate, followed by luteolin, kaempferol, and quercetin. Based on comparison of HPLC retention times with authentic flavonoid 7-O-glucosides and nuclear magnetic resonance spectroscopy, the glycosylation position in the reacted flavonoids was determined to be the C-7 hydroxyl group. These results indicate that AtGT-2 encodes a flavonoid 7-O-glucosyltransferase.

Functional Characterization and Protein Engineering of a Triterpene 3-/6-/2′-O-Glycosyltransferase Reveal a Conserved Residue Critical for the Regiospecificity

Engineering the function of triterpene glucosyltransferases (GTs) is challenging due to the large size of the sugar acceptors. In this work, we identified a multifunctional glycosyltransferase AmGT8 catalyzing triterpene 3-/6-/2′-O-glycosylation from the medicinal plant Astragalus membranaceus. To engineer its regiospecificity, a small mutant library was built based on semi-rational design. Variants A394F, A394D, and T131V were found to catalyze specific 6-O, 3-O, and 2′-O glycosylation, respectively. The origin of regioselectivity of AmGT8 and its A394F variant was studied by molecular dynamics and hydrogen deuterium exchange mass spectrometry. Residue 394 is highly conserved as A/G and is critical for the regiospecificity of the C- and O-GTs TcCGT1 and GuGT10/14. Finally, astragalosides III and IV were synthesized by mutants A394F, T131V and P192E. This work reports biocatalysts for saponin synthesis and gives new insights into protein engineering of regioselectivity in plant GTs.

pH-promoted O-α-glucosylation of flavonoids using an engineered α-glucosidase mutant

Retaining glycosidase mutants lacking its general acid/base catalytic residue are originally termed thioglycoligases which synthesize thio-linked disaccharides using sugar acceptor bearing a nucleophilic thiol group. A few thioglycoligases derived from retaining α-glycosidases have been classified into a new class of catalysts, O-glycoligases which transfer sugar moiety to a hydroxy group of sugar acceptors, resulting in the formation of O-linked glycosides or oligosaccharides. In this study, an efficient O-α-glucosylation of flavonoids was developed using an O-α-glycoligase derived from a thermostable α-glucosidase from Sulfolobus solfataricus (MalA-D416A). The O-glycoligase exhibited efficient transglycosylation activity with a broad substrate spectrum for all kinds of tested flavonoids including flavone, flavonol, flavanone, flavanonol, flavanol and isoflavone classes in yields of higher than 90%. The glucosylation by MalA-D416A preferred alkaline conditions, suggesting that pH-promoted deprotonation of hydroxyl groups of the flavonoids would accelerate turnover of covalent enzyme intermediate via transglucosylation. More importantly, the glucosylation of flavonoids by MalA-D416A was exclusively regioselective, resulting in the synthesis of flavonoid 7-O-α-glucosides as the sole product. Kinetic analysis and molecular dynamics simulations provided insights into the acceptor specificity and the regiospecificity of O-α-glucosylation by MalA-D416A. This pH promoted transglycosylation using O-α-glycoligases may prove to be a general synthesis route to flavonoid O-α-glycosides.

Exploring the catalytic promiscuity of a new glycosyltransferase from Carthamus tinctorius

The catalytic promiscuity of a new glycosyltransferase (UGT73AE1) from Carthamus tinctorius was explored. UGT73AE1 showed the capability to glucosylate a total of 19 structurally diverse types of acceptors and to generate O-, S-, and N-glycosides, making it the first reported trifunctional plant glycosyltransferase. The catalytic reversibility and regioselectivity were observed and modeled in a one-pot reaction transferring a glucose moiety from icariin to emodin. These findings demonstrate the potential versatility of UGT73AE1 in the glycosylation of bioactive natural products.

Polyphenolic compounds in Scopolia caucasica Kolesn. ex Kreyer (Solanaceae)

The qualitative and quantitative determinations of coumarins, phenolic acids and flavonoids in the leaves and underground parts of Scopolia caucasica using paper chromatography and HPLC methods were described. From the leaves of this plant, kaempferol 3-O-(2-glucosyl)-galactoside-7-O-glucoside, kaempferol 3-O-(2-glucosyl)-galactoside and quercetin 3-O-glucoside were isolated and identified by spectroscopic methods (UV, 1H- and 13C-NMR).

Purification and characterization of a flavonol 3-O-β heterodisaccharidase from the dried herb of Fagopyrum esculentum Moench

A flavonol-3-O-β-heterodisaccharide glycosidase (FHG I) was isolated from dried aerial tissues of Fagopyrum esculentum Moench (Fagopyri herba). It has a specific enzyme activity of ca. 3.5 nkat mg-1 protein in buffered extracts when rutin (quercetin-3-O-rutinoside) was used as substrate and an optimal enzyme activity was seen at around pH 4.8 and 30 °C. FHG I was purified about 156-fold to apparent homogeneity by hydrophobic interaction, anion exchange and size exclusion chromatographic steps. The apparent molecular mass of FHG I was 74.5 ± 2 kDa as determined by SDS-PAGE and it is a monomeric glycoprotein with a carbohydrate content of 23%. The isoelectric point as determined by isoelectric focusing was 5.7 and the energy of activation was 32 kJ mol-1. FHG I exhibits a high substrate specificity, preferring flavonol 3-O-glycosides comprising the disaccharide rutinose. The Km and Vmax values for the natural substrate rutin were calculated to be 0.561 μM and 745 nkat mg -1 protein, respectively. Two oligopeptide fragments obtained after enzymatic digestion of FHG I were sequenced and showed similarities to sequences of β-glucohydrolases from other plant species. Polyclonal antibodies were raised and their specificities determined. Another flavonol 3-O-β -heterodisaccharide glycosidase (FHG II) could also be detected in buckwheat herb, having a molecular mass of 85.3 ± 2 kDa and an isoelectric point between pH 6.0 and 6.5.