Product name: Astilbin
Synonym name: Taxifolin 3-rhamnoside
Catalogue No.: BP0208
Cas No.: 29838-67-3
Formula: C₂₁H₂₂O₁₁
Mol Weight: 450.396
Botanical Source: Engelhardtia roxburghiana Wall.leaf
Physical Description:
Type of Compound: Flavonoids

Purity: 95%~99%
Analysis Method: HPLC-DAD or/and HPLC-ELSD
Identification Method: Mass, NMR
Packing: Brown vial or HDPE plastic bottle

Storage: Store in a well closed container, protected from air and light. Put into refrigerate or freeze for long term storage.
Whenever possible, you should prepare and use solutions on the same day. However, if you need to make up stock solutions in advance, we recommend that you store the solution as aliquots in tightly sealed vials at -20℃. Generally, these will be useable for up to two weeks.

The product could be supplied from milligrams to grams
Inquire for bulk scale.

Description:

Astilbin has insecticidal, antioxidant, antibacterial, and anti-inflammatory activities, it may act as an efficient therapeutic agent for arthritis like cyclosporine A but with less toxicity, its mechanism includes a selective suppression on lymphocyte functions via reducing MMP and NO production. Astilbin can exert an early renal protective role to diabetic nephropathy (DN), inhibit production of transforming growth factor-beta1 (TGF-beta1) and connective tissue growth factor (CTGF).Astilbin also alleviates contact hypersensitivity through a unique mechanism involving a negative cytokine regulation through stimulating IL-10, which is distinct from the immunosuppressant cyclosporin A.

References:

J Ethnopharmacol. 2006 Jun 30;106(2):272-8.    

Isolation and in vitro antibacterial activity of astilbin, the bioactive flavanone from the leaves of Harungana madagascariensis Lam. ex Poir. (Hypericaceae).   

Harungana madagascariensis is well known for its topical antibacterial properties used in the elaboration of a lot of skin hygiene products. The aim of this study was, on the one hand, to evaluate the in vitro antibacterial activities of aqueous, ethanolic and ethyl acetate crude extracts of Harungana madagascariensis leaves against bacterial strains representative of skin microflora and, on the other hand, to determine the chemical structure of the active compound. Only the ethyl acetate leaf extract presented important antibacterial activity.

METHODS AND RESULTS:

Its fractionation was carried out by column chromatography using silica gel 60 and it yielded 11 fractions. A bioautographic method, revealed in these fractions the presence of a flavanone as the active compound Astilbin or 3-O-alpha-L-rhamnoside-5,7,3',4'-tetrahydroxydihydroflavonol which was identified on the basis of its spectroscopic data. Concerning the antibacterial activity against the representative skin microflora of the armpit and feet, MIC and MBC ranged from 25 to 250 and 100 to 750 microg ml-1, respectively. 

CONCLUSIONS:

The results showed that some bacteria considered to be responsible for bad odours at the armpit and feet levels, were destroyed at 200 microg ml-1 (MBC), a concentration sparing most of the useful saprophytic microflora. The minimal inhibitory quantity (MIQs) of Astilbin ranged from 50 to 100 microg.    

Food Chem.,2009,115(1):297-303.    

Antioxidant activity of Rhizoma Smilacis Glabrae extracts and its key constituent-astilbin.    

Rhizoma Smilacis Glabrae is widely consumed by Chinese as functional food and in folk medicine for its medicinal properties. In this study, methanol and water extracts of Rhizoma Smilacis Glabrae were prepared. The water extract was further divided into polysaccharide and supernatant fractions. 

METHODS AND RESULTS:

Constituents in different extracts were analysed by capillary electrophoresis, and levels of total phenolics were also determined using the Folin-Ciocalteu method. Astilbin, the main constituent in the herb, was isolated and purified. Different antioxidant tests were employed to evaluate the antioxidant activities of the extracts and the isolated Astilbin, and the results were compared with two commonly used synthetic antioxidants-butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). Methanol, water extract and supernatant fraction showed concentration dependent antioxidant activity while polysaccharide didn’t show any antioxidant activity. 

CONCLUSIONS:

Purified Astilbin showed the strongest antioxidant activity in comparison to any other extracts.    

Pest Manag Sci. 2002 May;58(5):503-7.    

Biological activity of astilbin from Dimorphandra mollis against Anticarsia gemmatalis and Spodoptera frugiperda.    

METHODS AND RESULTS:

Astilbin was isolated in high yield from Dimorphandra mollis, and its insecticidal and growth inhibiting activity by stomach ingestion were evaluated against Anticarsia gemmatalis and Spodoptera frugiperda. The insecticidal activity of Astilbin, the weight reduction of the larval phase and the prolongation of the larval and pupal phases were verified for both species. 

CONCLUSIONS:

Astilbin was identified on the base of its NMR, MS and physical data.    

Food Chem Toxicol. 2014 Jan;63:104-10.    

Astilbin protects diabetic rat heart against ischemia-reperfusion injury via blockade of HMGB1-dependent NF-κB signaling pathway.    

Astilbin, a flavonoid compound was isolated from the rhizome of Smilax china L. 

METHODS AND RESULTS:

In this study, we investigated the anti-myocardial ischemia and reperfusion (I/R) injury effect of Astilbin on diabetic rats in vivo and elucidated the potential mechanism in vitro. The results showed that Astilbin significantly attenuated hypoxia-induced cell injury in a concentration-dependent manner. Treatment of H9c2 cells with Astilbin at 15 μM blocked nuclear factor kappaB (NF-κB) phosphorylation by blocking High-mobility group box protein 1 (HMGB1) expression. Treatment of diabetic rats with Astilbin by intravenous injection (i.v.) at a single dose of 50 mg/kg protected the rats from myocardial I/R injury as indicated by decreasing infarct volume, improving hemodynamics and reducing myocardial damage, and also lowered serum levels of pro-inflammatory factors, reduced HMGB1 and phosphorylated NF-κB expression in ischemic myocardial tissue from diabetic rats. Additionally, treatment of diabetic rats with Astilbin at dose of 50 mg/kg by i.v. for continuous 14 days attenuated cardiac remodeling in the model myocardial I/R injury. 

CONCLUSIONS:

These protective effects suggested that Astilbin might be due to block of the myocardial inflammatory cascade via the HMGB1-dependent NF-κB signaling pathway.    

J Pharm Pharmacol. 2004 Apr;56(4):495-502.    

Astilbin prevents concanavalin A-induced liver injury by reducing TNF-alpha production and T lymphocytes adhesion.   

The aim of this study was to evaluate the effect of Astilbin on concanavalin A (Con A)-induced hepatitis, a T cell-dependent model of liver injury. 

METHODS AND RESULTS:

Con A administration resulted in a severe liver injury in mice, with a strong increment in spleen cell adhesion and liver infiltration of T cells, as well as in tumour necrosis factor (TNF)-alpha production. Against this liver injury, Astilbin significantly inhibited the elevation in transaminase activity, reduced the TNF-alpha production, and improved the histological changes, including inflammatory infiltration, hepatocyte necrosis and degeneration and Kupffer cell hyperplasia. In addition, Astilbin inhibited the adhesion of spleen cells and purified T lymphocytes isolated from the liver-injured mice to fibronectin, laminin and type IV collagen.Moreover, the adhesion of human Jurkat T cells to endothelial cell line ECV-304 was also inhibited by Astilbin. 

CONCLUSIONS:

These results suggest that the improvement of the T cell-mediated liver injury by Astilbinmay be related to the reduction in TNF-alpha production and in T cell adhesion to extracellular matrices and endothelial cells.   

HPLC of Astilbin

HNMR of Astilbin

Storage conditions：Short-term storage at 2~8℃, long-term storage at -20 ~ -80℃

Introduction/Overview

Astilbin, also known as (2R, 3R) -3,5,7-trihydroxy-2- (3-hydroxy-4-methoxyphenyl) -4-benzodihydropyran-3- α - L-rhamnoside, is a natural dihydroflavonol glycoside with significant biological activity. Its CAS number is 29838-67-3 and it is widely present in various medicinal plants, such as Smilax glabra and Astilbe plants. It is often used in traditional medicine to treat inflammation and immune related diseases. In recent years, with the deepening of modern pharmacological research, Luoxinfu glycoside has attracted much attention due to its multi-target and multi pathway pharmacological effects, especially in anti-inflammatory, antioxidant, endothelial function protection, and regulation of metabolic disorders, showing great potential. Its core mechanism involves the activation of the nuclear factor E2 related factor 2 (NRF2) pathway and the inhibition of the nuclear factor kappa B (NF - κ B) signaling pathway, providing a theoretical basis for its prevention and treatment of chronic inflammation related diseases such as cardiovascular disease, metabolic syndrome, and neurodegenerative diseases. This article aims to systematically review the chemical properties, plant sources, pharmacological activities, molecular mechanisms, medicinal properties, and clinical application prospects of Luoxinfu glycoside, in order to provide comprehensive scientific references for the in-depth research and development of this compound.

Chemical structure and physicochemical properties

The molecular formula of Luoxinfu glycoside is C21H22O11, with a molecular weight of 450.3960 g/mol. Its basic skeleton is dihydroflavonol (flavanone), and its specific structure is (+) - Taxifolin, which is connected to an α - L-rhamnose group through a glycosidic bond at the C-3 position. This structure contains multiple phenolic hydroxyl groups (3,5,7,3 ', 4' - pentahydroxyl, with the 4 'position often being a methoxy substituted variant), which are key functional groups for its antioxidant and free radical scavenging activities. Luoxinfu glycoside exists in stereoisomers, with the common configuration described in the article being (2R, 3R), which differs from the enantiomer Neoastilbin in the C-2 and C-3 configurations.

In terms of physical and chemical properties, the calculated value of the lipid water partition coefficient (LogP) of Luoxinfu glycoside is about 0.4969, indicating that it has a certain degree of hydrophilicity. Its topological polar surface area (TPSA) is as high as 186.37 Å ², mainly attributed to the numerous hydrogen bond donors and acceptors (hydroxyl and sugar groups) in the molecule. The theoretical water solubility value is about 3.8585mg/L, which belongs to the category of slightly soluble to poorly soluble, and this needs to be considered in practical extraction and formulation. Crystals usually appear as light yellow to white powder. Its UV absorption characteristic peak is around 290 nm, which can be used for qualitative and quantitative analysis. Luoxinfu glycoside is relatively stable under acidic conditions, but its glycosidic bonds and phenolic hydroxyl structures may undergo hydrolysis or oxidation under strong alkaline or high temperature conditions. Therefore, pH and temperature should be carefully controlled during extraction, storage, and processing.

Plant sources and extraction methods

Luoxinfu glycoside is relatively widely distributed in nature and mainly exists in the following plant families and genera:
1. Liliaceae family The most important source is the rhizome of Smilax glabra Roxb., a traditional Chinese medicine commonly used for clearing heat and dampness, detoxifying and reducing swelling. Luoxinfu glycoside is considered one of its key active ingredients.
2. Saxifragaceae family The compound is named after the genus name of Astilbe plants, such as Astilbe chinensis.
3. Other sources Trace amounts have also been detected in grape seeds, some ferns, and certain fruits.

The extraction of Luoxinfu glycoside mainly adopts solvent extraction method, supplemented by modern separation and purification technology.
* extraction process Ethanol water or methanol water systems are commonly used for reflux extraction or ultrasound assisted extraction. The extraction efficiency is affected by solvent concentration, solid-liquid ratio, temperature, and time. For example, using a 60-70% ethanol solution for hot reflux extraction of Poria cocos powder is a common and effective method.
* Separation and purification After concentration, the crude extract is enriched by macroporous adsorption resins (such as AB-8, D101) and eluted with a gradient of water and different concentrations of ethanol. Luoxinfu glycoside is usually eluted in the medium to high concentration ethanol elution fraction. Further purification relies on column chromatography techniques such as silica gel column chromatography, polyamide column chromatography, and high-performance liquid chromatography (HPLC) preparative chromatography. Semi preparative or preparative HPLC is currently the most reliable method for obtaining high-purity standard samples of rosmarin.
* Identification Method The structural identification of compounds comprehensively utilizes techniques such as ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS), nuclear magnetic resonance spectroscopy (NMR, especially 1H-NMR and 13C-NMR), and optical rotation determination.

Pharmacological activity research

A large number of in vitro and in vivo studies have shown that Luoxinfu glycoside has a wide range of pharmacological activities, with its core revolving around anti-inflammatory, antioxidant, and cell protective effects.

1. Anti inflammatory and immune regulatory effects Luoxinfu glycoside is a potent natural anti-inflammatory agent. In various inflammatory models, such as lipopolysaccharide induced macrophage RAW264.7 inflammation model, carrageenan induced rat paw swelling model, and collagen induced arthritis mouse model, Luoxinfu glycoside can significantly inhibit the production of pro-inflammatory cytokines (such as TNF - α, IL-1 β, IL-6) and the release of nitric oxide (NO). Its immune regulatory effect is reflected in the regulation of T lymphocyte proliferation and differentiation, which may have therapeutic value for autoimmune diseases.

2. Antioxidant and NRF2 activation The multiple phenolic hydroxyl structures of Luoxinfu glycoside enable it to effectively scavenge free radicals such as DPPH and ABTS, and exhibit significant iron ion reduction ability. More importantly, it can activate the core transcription factor NRF2 (encoded by the NFE2L2 gene) for cellular defense. Luoxinfu glycoside promotes the dissociation and nuclear translocation of NRF2 from the cytoplasmic chaperone protein Keap1, thereby upregulating the expression of downstream antioxidant and phase II detoxifying enzyme genes, such as heme oxygenase-1 (HO-1), quinone oxidoreductase 1 (NQO1), glutathione S-transferase (GST), etc., thereby enhancing the cell's ability to resist oxidative stress damage.

3. Protective effect of endothelial function Endothelial dysfunction is the initial link of cardiovascular diseases such as atherosclerosis and vascular complications of diabetes. Luoxinfu glycoside protects endothelial cells through multiple pathways: inhibiting endothelial cell apoptosis induced by high glucose or oxidized low-density lipoprotein; Downregulate the expression of matrix metalloproteinase-2 (MMP-2), alleviate extracellular matrix degradation, and stabilize plaques; Improve endothelial dependent vasodilation function. Its endothelial protective effect is closely related to the inhibition of NF - κ B pathway, activation of NRF2 pathway, and regulation of related proteins such as STAT3 and PRKCA.

4. Anti fibrotic effect In liver fibrosis and pulmonary fibrosis models, rosmarin has shown inhibitory effects on collagen deposition and reduced fibroblast activation, which may be related to the inhibition of the TGF - β 1/Smad signaling pathway and inflammatory response.

5. Other activities The study also suggests that astilboside has anti diabetes potential (possibly related to the inhibition of aldose reductase AKR1B1), slight analgesic effect, and possible neuroprotective effect by inhibiting acetylcholinesterase (BCHE).

Mechanism of action and molecular targets

The core of the multifunctional pharmacological effects of Luoxinfu glycoside lies in its regulation of multiple key signaling pathways and its action on multiple molecular targets. According to the provided target information, its action network can be summarized as follows:

• Core anti-inflammatory pathway: inhibition of NF - κ B signaling Luoxinfu glycoside can effectively inhibit the activation of NF - κ B. It may inhibit the nuclear translocation of NF - κ B p65 subunit by interfering with the activation of IKK complex, preventing the phosphorylation and degradation of I κ B α. This directly leads to a decrease in transcription of downstream pro-inflammatory cytokine genes such as TNF - α and IL-6. target STAT3 As an important signaling molecule for inflammation and cell survival, its activation may also be inhibited by lovastatin, synergistically exerting anti-inflammatory effects.

• Core antioxidant pathway: activation of NRF2/ARE signaling As mentioned earlier, Luoxinfu glycoside is an effective activator of NRF2 (target)NFE2L2）. This forms the cornerstone of its cellular protective effect, combating various types of damage caused by oxidative stress.

• Targets related to endothelial protection and metabolic regulation：

  • APP (amyloid precursor protein)Luoxinfu glycoside may indirectly affect endothelial function or neuronal activity by regulating APP metabolism, and the specific mechanism needs to be elucidated.
  • PTPN1 (protein tyrosine phosphatase 1B)As a negative regulator of the insulin signaling pathway, inhibition of PTPN1 can improve insulin sensitivity. Astiriflorin may play an anti diabetes role through this target.
  • PRKCA (protein kinase C alpha)Overactivation of PKC α is involved in vascular complications and endothelial dysfunction in diabetes. Luoxinfu glycoside's inhibition helps maintain vascular homeostasis.
  • AKR1B1 (aldose reductase)Inhibition of this enzyme can reduce the abnormal accumulation of sorbitol in tissues (such as nerves, lenses, and blood vessels), which is crucial for the prevention and treatment of complications of diabetes.
  • MMP2 (Matrix Metalloproteinase 2)Astiriflorin down regulates the expression of MMP2, which helps to stabilize atherosclerotic plaque and prevent rupture.
  • XDH (xanthine dehydrogenase/oxidase)Inhibiting XDH can reduce the production of uric acid and superoxide anions, and has both uric acid lowering and antioxidant effects.
  • P4HB (Prolyl 4-hydroxylase β subunit)Participate in collagen synthesis, which may be related to its anti fibrotic effect.
  • BCHE (butyrylcholinesterase)Inhibition of BCHE may enhance cholinergic signaling and potentially be used in research on neurodegenerative diseases.

Luoxinfu glycoside exerts synergistic effects on pathological processes such as inflammation, oxidative stress, metabolic abnormalities, and cell apoptosis through this multi-target network, thus demonstrating therapeutic potential for various complex diseases.

Evaluation of drug properties and pharmacokinetics

Based on the provided parameters and existing research, the preliminary evaluation of the pharmacological properties of Luoxinfu glycoside is as follows:

• Preliminary analysis of drug properties The molecular weight of 450.4 is slightly higher than the 500 standard of the "Five Rules for Generic Drugs", but still within an acceptable range. The LogP value (0.5) is moderate, and the TPSA value (186) is high, indicating that its membrane permeability may be average. The low theoretical water solubility is the main physical and chemical bottleneck affecting its bioavailability.
• Absorption, distribution, metabolism, excretion (ADME)：
  • absorb As a flavonoid glycoside, the absorption of rosmarin in the intestine may be limited by its polarity and molecular size. Studies have shown that its oral bioavailability is low, which may be related to gut microbiota hydrolysis, first pass effects, and P-glycoprotein efflux. Formulation technologies such as nanocrystals, phospholipid complexes, and cyclodextrin inclusion complexes are key strategies for improving their oral absorption.
  • distribution Its blood-brain barrier permeability is predicted to be "low", which is consistent with high TPSA values, indicating that its prototype drug may have difficulty entering the central nervous system, but has little impact on its peripheral targets such as blood vessels and liver.
• Preliminary Safety Assessment：
  • HERG inhibition A prediction of 'no' indicates a low risk of potential cardiac toxicity (inducing long QT syndrome), which is a favorable safety feature.
  • Genotoxicity The Ames test (evaluating mutagenicity) result is 0.6, and it is generally considered negative if it is less than twice the control value, indicating no significant mutagenic risk under the testing conditions. However, a more complete genetic toxicity test combination is needed for confirmation.
• Current status of pharmacokinetic research Animal pharmacokinetic studies have shown that after intravenous administration, the distribution of puerarin is faster and the elimination half-life is relatively short. After oral administration, the blood drug concentration is low, and the peak time (Tmax) is about 1-2 hours. Its main metabolic pathways may include hydrolysis of glycosidic bonds (to produce the aglycone paclitaxel), glucuronidation, and sulfation binding reactions. The main excretion pathways may be through the kidneys and bile.

In summary, Luoxinfu glycoside has good pharmacological activity and preliminary safety signals, but its poor solubility and oral bioavailability are the main challenges it faces in drug development. It is expected to overcome these obstacles through prodrug modification or the development of new drug delivery systems.

Clinical application prospects and prospects

The multi-target pharmacological properties of Luoxinfu glycoside have depicted broad prospects for its application in various chronic disease fields.

1. Cardiovascular and metabolic diseases Based on its strong endothelial protection, anti-inflammatory and antioxidant effects, astilboside is a potential candidate drug for the prevention and treatment of atherosclerosis, hypertension, diabetes and its vascular complications (such as diabetes nephropathy, retinopathy). Its role in inhibiting AKR1B1 and PTPN1 further strengthens its position in the management of diabetes.

2. Autoimmune and inflammatory diseases Luoxinfu glycoside can exert therapeutic effects on chronic inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease, psoriasis, etc. by inhibiting NF - κ B and regulating immune cell function. Its natural product identity may bring better long-term medication safety.

3. Anti fibrotic therapy In the fields of liver fibrosis (such as non-alcoholic fatty liver disease), pulmonary fibrosis, etc., the anti-inflammatory and collagen synthesis inhibiting effects of rosuvastatin are worthy of further exploration.

4. neuroprotection Although the blood-brain barrier has low permeability, its inhibition of BCHE and anti-inflammatory and antioxidant properties, as well as its potential to indirectly affect the central nervous system by regulating peripheral inflammation, still have research value in the prevention or adjuvant treatment of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. Developing derivatives or delivery systems that can cross the blood-brain barrier is key.

5. Challenges and Strategies in Drug Development：

   • challenge Mainly including low oral bioavailability, fast metabolism in vivo, complex mechanism of action network leading to difficulties in identifying key targets, and cost issues in obtaining high-purity raw materials from plants.
   • Strategy：
     • structural optimization Improve its solubility, stability, and membrane permeability through chemical modifications such as preparing prodrugs, modifying sugar or phenolic hydroxyl groups.
     • delivery system Develop new formulations such as liposomes, nanoparticles, microemulsions, and solid dispersions to improve their solubility and targeting properties.
     • In depth mechanism research Using techniques such as gene knockout/knockdown and chemical proteomics, precisely elucidate the most critical targets and pathways for its therapeutic effects.
     • Synthetic Biology Explore the green and sustainable large-scale production of rosmarin through microbial fermentation or plant cell culture and other biosynthetic methods.

In the future, with more refined analysis of the pharmacological network of Luoxinfu glycoside and breakthroughs in pharmaceutical technology, it is expected to develop from a promising lead compound into an innovative drug or functional food additive for the treatment of various chronic inflammation related diseases.

Conclusion

Luoxinfu glycoside, as a dihydroflavonol glycoside derived from traditional medicinal plants, shines brightly in modern pharmacological research due to its unique chemical structure and multi-target pharmacological mechanism of action. It exhibits significant efficacy in anti-inflammatory, antioxidant, endothelial function protection, and metabolic regulation by synergistically activating the NRF2 antioxidant pathway and inhibiting the NF - κ B inflammatory pathway. It has potential preventive and therapeutic value for various major chronic diseases such as cardiovascular disease, metabolic syndrome, and autoimmune diseases. Although it faces challenges such as low bioavailability in drug development, this is precisely the direction that modern medicinal chemistry and pharmacy can focus on breaking through. The in-depth study of the mechanism of action, rational structural optimization, and innovative drug delivery strategies will jointly promote the transformation process of Luoxinfu glycoside from laboratory to clinical application. The continuous exploration of Luoxinfu glycoside not only contributes to the development of new therapeutic drugs, but also reflects the enormous potential of exploring modern therapeutic value from the treasure trove of traditional medicine, providing a model for innovative research and development of natural products.