Introduction/Overview
Quercetin-3-O-D-glucosyl - (1-2) - L-rhamnoside (Quercetin-3-O-glucosyl) is an important natural product and belongs to the O-glycoside derivative of quercetin flavonoids. As one of the active ingredients in Ginkgo biloba leaves, quercetin diglycoside has attracted widespread attention in the field of natural product pharmacology in recent years due to its significant antioxidant activity and multi-target pharmacological effects. This compound not only exhibits excellent anti allergic effects, but also involves multiple inflammatory response related signaling pathways, demonstrating enormous value as a potential drug candidate molecule. This article will systematically review the chemical structure and physicochemical properties, plant sources and extraction methods, pharmacological activity and mechanism of action, pharmacological evaluation and pharmacokinetic characteristics of quercetin diglycoside, and explore its clinical application prospects and future development directions.
Chemical structure and physicochemical properties
The molecular formula of quercetin diglycoside is C27H30O16, with a molecular weight of 610.5210 Da. Its basic skeleton is quercetin, a typical flavonoid compound. The 3-hydroxyl group is connected to L-rhamnose through a 1 → 2 glycosidic bond via a β - D-glucose group to form a diglycoside structure. Glycosylation significantly affects the water solubility, bioavailability, and pharmacokinetic properties of quercetin.
In terms of physicochemical properties, quercetin diglycoside exhibits high polarity, with a topologically polar surface area (TPSA) of 269.43 Å ², indicating its strong hydrophilicity. The LogP value is -0.4020, further confirming its low fat solubility characteristics. The water solubility is 3.8427, which is significantly higher than that of quercetin mother nucleus, and is beneficial for absorption and distribution in the body. Its blood-brain barrier permeability is low, indicating difficulty in entering the central nervous system. The negative result of hERG channel inhibition experiment indicates a low risk of cardiac toxicity. The Ames test score is 1.2, indicating a low risk of genetic toxicity.
The multiple hydroxyl and sugar groups in the molecular structure not only endow it with good antioxidant capacity, but also affect its binding mode and affinity with target proteins by forming hydrogen bonds with biomolecules. The glycosylation modification of the overall structure is a key characteristic that distinguishes this compound from quercetin and its monoglycosides, determining its unique pharmacological activity and pharmacokinetic performance.
Plant sources and extraction methods
Quercetin glucoside is mainly isolated from Ginkgo biloba leaves. Ginkgo biloba, as an ancient gymnosperm, is rich in various flavonoids and their glycoside derivatives in its leaves, making it an important raw material for traditional Chinese medicine and modern health products. Quercetin diglycoside, as one of the flavonoids in Ginkgo biloba leaves, although not as abundant as quercetin monoglycoside, its biological activity cannot be ignored.
The extraction method usually uses organic solvent extraction combined with column chromatography separation technology. The specific process includes:
- Sample Pretreatment Dry and crush ginkgo leaves, and screen for uniform particles.
- Solvent extraction Use 70% -80% ethanol aqueous solution for reflux extraction, with extraction temperature controlled at 60-80 ℃ and time of about 2-4 hours.
- Crude extract concentration Reduce pressure and concentrate to remove most of the solvent.
- Separation and purification Separation is carried out by silica gel column chromatography or reverse phase C18 column, using gradient elution technique and combined with high-performance liquid chromatography (HPLC) to monitor the target components.
- Structural Identification Confirm the structure of the compound using modern analytical techniques such as mass spectrometry (MS) and nuclear magnetic resonance (NMR).
In recent years, the application of ultrasound assisted extraction and microwave-assisted extraction technologies has improved extraction efficiency and purity, while reducing energy consumption and time costs. In addition, the introduction of ionic liquid assisted extraction and molecular imprinting techniques provides new ideas for the efficient separation of quercetin diglycosides.
Pharmacological activity research
The pharmacological activities of quercetin diglycoside mainly focus on antioxidant and anti allergic aspects.
antioxidant activity
As a glycoside derivative of quercetin, quercetin diglycoside retains the polyphenolic hydroxyl structure of the parent nucleus and has the ability to scavenge free radicals and inhibit lipid peroxidation. In vitro studies have shown that the compound can effectively scavenge DPPH radicals, hydroxyl radicals, and superoxide anions, exhibiting excellent antioxidant capacity. Its antioxidant effect is to some extent superior to quercetin monoglycoside, which may be related to the improvement of solubility and stability by glycosylation modification.
Antioxidant activity makes it have potential application value in the prevention and treatment of oxidative stress related diseases (such as cardiovascular diseases, neurodegenerative diseases, diabetes, etc.). In vivo experiments have also confirmed that it can enhance antioxidant enzyme activity, reduce levels of oxidative damage markers, and alleviate tissue damage.
Anti allergic effect
In recent years, research on quercetin diglycoside in the field of anti allergy has gradually deepened. It exerts significant anti allergic effects by regulating various allergy related targets. The main targets include:
- ALOX5 (5-lipoxygenase)Participate in leukotriene synthesis and regulate the production of inflammatory mediators.
- HRH1 (histamine H1 receptor)Mediate allergic symptoms caused by histamine.
- IL4、IL5、IL13 Key Th2 cells secrete cytokines that promote IgE synthesis and eosinophil activation.
- FCER1A (high affinity IgE receptor alpha chain)Regulating the activation of mast cells and eosinophils.
- TBXA2R (thromboxane A2 receptor)Participate in platelet aggregation and airway contraction.
- STAT6 (Signal Transduction and Transcription Activation Factor 6)Regulating the IL4/IL13 signaling pathway to promote allergic reactions.
- TSLP (thymic stromal lymphopoietin)Activate dendritic cell-mediated allergic inflammation.
In vitro cell models and animal experiments have shown that quercetin diglycoside can inhibit the expression and activity of these targets, reduce the release of inflammatory mediators, and alleviate allergic symptoms. In addition, its inhibitory effect on degranulation of mast cells further confirms its anti allergic potential.
Other pharmacological effects
In addition to the main activities mentioned above, quercetin glucoside also exhibits certain anti-inflammatory, anti-tumor, and neuroprotective effects. It inhibits the release of inflammatory factors and reduces tissue inflammation by regulating signaling pathways such as NF - κ B and MAPK. Meanwhile, some studies have revealed its regulatory effects on tumor cell proliferation and apoptosis, suggesting its potential value in adjuvant therapy for tumors.
Mechanism of action and molecular targets
The mechanism of action of quercetin diglycoside is complex and diverse, mainly achieved through multi-target and multi pathway synergistic regulation to achieve its pharmacological effects.
Antioxidant mechanism
Quercetin glucoside alleviates oxidative stress by directly clearing free radicals and activating endogenous antioxidant enzyme systems such as superoxide dismutase (SOD) and glutathione peroxidase (GPx). Its polyphenolic hydroxyl structure can undergo electron transfer reaction with reactive oxygen species, terminating the chain reaction of free radicals. In addition, glycosylation modification improves its stability in aqueous environments and enhances its antioxidant effect.
Anti allergic mechanism
Quercetin diglycoside inhibits allergy related signaling pathways through multi-target inhibition:
- Inhibition of ALOX5 activity Reduce leukotriene production, alleviate airway inflammation and contraction.
- Antagonistic HRH1 receptor Blocking histamine mediated increase in vascular permeability and neural stimulation.
- Downregulate the expression of IL4, IL5, and IL13 Inhibit Th2 cell-mediated immune response, reduce IgE synthesis and eosinophil infiltration.
- Inhibition of FCER1A mediated degranulation of mast cells Reduce the release of histamine and other allergens.
- Blocking the STAT6 signaling pathway Regulating the expression of allergy related genes.
- Inhibit TSLP production Weaken dendritic cell activation and Th2 biased immune response.
These effects collectively alleviate allergic inflammation and alleviate clinical allergic symptoms.
Other mechanisms
Quercetin glucoside also exerts anti-inflammatory effects by regulating the NF - κ B and MAPK signaling pathways, inhibiting the release of pro-inflammatory cytokines such as TNF - α and IL-1 β. In tumor cells, it induces cell cycle arrest and apoptosis, which may involve mitochondrial pathways and regulation of apoptosis related proteins.
Evaluation of drug properties and pharmacokinetics
The pharmacological evaluation of quercetin diglycoside shows certain advantages and challenges.
Analysis of drug properties parameters
- Molecular weight (610.52 Da)Slightly higher than the ideal range of traditional small molecule drugs (<500 Da), which may affect oral absorption.
- LogP（-0.4020）Low fat solubility is beneficial for water solubility and in vivo distribution, but may limit cell membrane penetration.
- TPSA（269.43 Ų）A higher polar surface area indicates poorer passive diffusion ability.
- Water solubility (3.8427)Good water solubility is beneficial for formulation development and in vivo dissolution.
- Low permeability of blood-brain barrier Suitable for targeting peripheral targets to reduce the risk of central nervous system side effects.
- HERG inhibition negative Good cardiac safety.
- Ames test has low genetic toxicity High security.
Overall, quercetin diglycoside is suitable for development as an oral or injectable medication, but its bioavailability and in vivo stability need to be optimized.
Pharmacokinetic characteristics
Currently, there is limited systematic pharmacokinetic research on quercetin diglycoside. Previous studies have shown that its glycoside structure may be converted by gut microbiota and enzymatic hydrolysis into quercetin core and monoglycosides in vivo, affecting its biological activity and metabolic pathways. The oral absorption rate is low, the first pass effect is significant, and the plasma half-life is moderate.
In the future, in-depth in vivo metabolic kinetics research is needed, including absorption, distribution, metabolism, and excretion (ADME) processes, to clarify their active metabolites and targets of action, providing a basis for clinical development.
Clinical application prospects and prospects
Quercetin glucoside has broad clinical application potential due to its excellent antioxidant and anti allergic activities.
Anti allergic diseases
The incidence of allergic diseases such as asthma, allergic rhinitis, eczema and other incidence rate is increasing year by year. The existing treatment methods have side effects and drug resistance problems. Quercetin diglycoside exhibits natural and safe advantages through multi-target regulation of allergic reactions, and is expected to become a new type of anti allergic drug or adjuvant therapy.
Antioxidant related diseases
Oxidative stress plays a key role in the occurrence and development of cardiovascular diseases, neurodegenerative diseases, diabetes and tumors. The antioxidant capacity of quercetin diglycoside makes it potentially useful for the prevention and adjuvant treatment of these diseases, especially for chronic disease management and healthcare.
Drug development and formulation innovation
Due to its good water solubility, quercetin diglycoside is suitable for developing various dosage forms, including oral tablets, capsules, injections, and topical medications. The application of novel drug delivery systems such as nanocarriers, liposomes, and solid dispersions is expected to improve their bioavailability and targeting.
Future research directions
- In depth mechanism research The system elucidates its multi-target action network and signaling pathway regulation mechanism.
- Pharmacokinetic and Metabolic Studies Clarify the metabolites and their activities in the body, and optimize the dosing regimen.
- safety evaluation Long term toxicology and preclinical safety studies.
- clinical trial Conduct clinical validation for allergic diseases and oxidative stress-related diseases.
- Structural modification and derivative development Improve drug properties and efficacy through chemical modification.
Conclusion
Quercetin 3-O-glucosyl (1 → 2) rhamnoside, as an important natural flavonoid glycoside in Ginkgo biloba leaves, has shown wide application prospects due to its unique chemical structure and diverse pharmacological activities. Its excellent antioxidant and anti allergic mechanisms provide a solid foundation for the development of new natural medicines. In the future, through in-depth pharmacological mechanism analysis, pharmacokinetic optimization, and clinical research, quercetin diglycoside is expected to become an effective candidate drug for the treatment of allergic diseases and oxidative stress-related diseases, promoting the development of natural product pharmacology and drug development.
![Quercetin-3-O-D-glucosyl]-(1-2)-L-rhamnoside](/upload/0201/6bc5363b860dca6e0434d28814e29239.png)
