Product name: Kaempferol
Synonym name:
Catalogue No.: BP0820
Cas No.: 520-18-3
Formula: C₁₅H₁₀O₆
Mol Weight: 286.239
Botanical Source: Very widespread in the plant world, e.g. in Cruciferae, Apocynaceae, Dilleniaceae, Ranunculaceae, Leguminosae, etc.
Physical Description: Yellow powder
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, up to kilograms
Inquire for bulk scale.

Descriptions:
Kaempferol is a polyphenol antioxidant found in fruits and vegetables, has beneficial effects in reducing the risk of chronic diseases, especially cancer, it may help to promote the development of cancer by augmenting the body's antioxidant defence against free radicals,and inhibit cancer cell growth and angiogenesis and induce cancer cell apoptosis.[1]
Kaempferol and quercetin have anti-inflammatory effects by modulating of iNOS, COX-2 and CRP, and involving blockade of NF-κB activation and the resultant up-regulation of the pro-inflammatory genes.[2]
Kaempferol is an autophagic enhancer, has a more general protection in Parkinson's disease, can mediate antiapoptotic and antioxidant effects is the enhancement of mitochondrial turnover by autophagy.[3]
Kaempferol and quercetin at concentrations ranging from 0.1 to 100 microM reduce bone resorption in a time and dose-dependent manner, have significant inhibitory effects at concentrations as low as 0.1 microM especially with kaempferol, they exert a potent inhibitory effect on in vitro bone resorption.[4]

References:
[1] Chen A Y, Chen Y C.Food Chem, 2013, 138(4):2099-107.
[2] García-Mediavilla V, Crespo I, Collado P S, et al. Eur J Pharmacol, 2007, 557(2–3):221-9.
[3] Filomeni G, Graziani I, Zio D D, et al. Neurobiol Aging, 2012, 33(4):767-85.
[4] Wattel A, Kamel S, Mentaverri R, et al. Biochem Pharmacol, 2003, 65(1):35-42.
[5] Yuanqing F U, Fengwei M O, Liao H. Medicinal Plant, 2013(1):42-43, 46.

HPLC of Kaempferol

NMR of Kaempferol

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

Introduction/Overview

Kaempferol, CAS number 520-18-3, is a natural flavonoid compound widely found in various plants, attracting attention for its diverse biological activities and potential medicinal value. As an important member of flavonoid compounds, kaemprol exhibits significant pharmacological effects in antioxidant, anti-anti-tumor, and neuroprotective effects, especially exhibiting unique mechanisms in tumor cell growth inhibition and apoptosis induction. In recent years, with the advancement of molecular biology and pharmacological research, kaempabol has made significant progress in the treatment of various malignant tumors such as breast cancer, glioblastoma, and lung cancer, demonstrating its broad prospects as a potential anti-cancer drug.

This paper aims to systematically review the chemical structure and physicochemical properties of kaempol, plant origin and extraction methods, pharmacological activity and mechanism of action, druggability evaluation, and pharmacokinetic characteristics, and to explore its clinical application potential and future development directions, providing comprehensive and in-depth reference materials for researchers in the field of natural product pharmacology.

Chemical structure and physicochemical properties

The chemical name of kaempabol is 3,4',5,7-tetrahydroxyflavone, with the molecular formula C15H10O6 and a molecular weight of 286.2390. Its structural core is a typical flavonoid backbone, formed by two benzene rings (A and B rings) connected by a tri-carbon bridge (C ring). Kaemprol contains multiple hydroxyl groups on the A and B rings, which impart excellent antioxidant activity. Its chemical structure is shown in Figure 1:

(This should include a schematic diagram of the chemical structure of kaempol)

In terms of physicochemical properties, the LogP value of kaempol is 2.0477, indicating moderate lipid solubility, which facilitates penetration of cell membranes. Its topological polar surface area (TPSA) is 111.1300 Ų, indicating certain polarity that affects its water solubility and bioavailability. Its low water solubility (0.1198 mg/mL) somewhat limits its oral absorption and bioavailability. Additionally, sannolol does not significantly inhibit hERG channels, with an Ames test result of 0.6, indicating low genotoxicity risk and good safety.

Plant Origins and Extraction Methods

Kaempol is widely found in a variety of edible fruits, vegetables, and medicinal plants, with common sources including cabbage, spinach, green tea, thyme, onions, and various berries. Its content varies depending on plant species, tissue location, growing environment, and harvest time. As a natural flavonoid, kaempabol is usually extracted using organic solvents, such as ethanol, methanol, or ethyl acetate, combined with modern technologies like ultrasound-assisted extraction and microwave-assisted extraction to improve extraction efficiency and purity.

Common extraction processes include: plant drying and pulverization→ solvent extraction → filtration concentration→ column chromatography separation and purification→ high-performance liquid chromatography (HPLC) analysis and identification. In recent years, supercritical fluid extraction and membrane separation technologies have also been applied to the extraction of kaempaol, further enhancing the green, environmentally friendly, and economic benefits of extraction.

Pharmacological activity research

Antioxidant activity

As a natural flavonoid antioxidant, kaempabol can effectively eliminate free radicals and reduce cellular damage caused by oxidative stress. Its antioxidant mechanism mainly regulates the signaling pathway of nuclear factor red cell red cell 2-related factor 2 (NFE2L2/NRF2), enhancing cellular antioxidant defenses and protecting cells from oxidative damage.

Antitumor activity

Kaempol exhibits significant anti-proliferative and pro-apoptotic effects in various tumor cell lines. Especially in breast cancer cells, kaemprol can inhibit the expression of estrogen receptor α (ERα), block estrogen signaling pathways, and suppress tumor cell growth and division. Additionally, in glioblastoma and lung cancer cells, kaemprol exerts anti-tumor effects by activating the MEK-MAPK signaling pathway, inducing apoptosis. Related studies have shown that kaemprol can regulate the expression of various cyclins and apoptosis-related proteins, such as Bcl-2 family proteins and caspase enzymes, promoting programmed death of tumor cells.

Other pharmacological effects

In addition to antioxidant and antitumor properties, kaemprol also possesses multiple biological activities including anti-inflammatory, antibacterial, neuroprotective, and cardiovascular protection. For example, kaemprol can inhibit the release of inflammatory mediators and alleviate chronic inflammatory responses; In neurological disease models, kaemprol protects neurons through antioxidant and anti-inflammatory mechanisms, demonstrating potential therapeutic value.

Mechanism of action and molecular targets

The pharmacological effects of kaemprol involve multiple signaling pathways and molecular targets, mainly including:

1. Antioxidant mechanism
   Kaempol activates the NFE2L2/NRF2 transcription factor, promoting the expression of downstream antioxidant enzyme genes such as SOD1, SOD2, CAT, GPX1, and HMOX1, thereby enhancing cellular resistance to oxidative stress. Additionally, kaemprol can directly eliminate reactive oxygen species (ROS), reducing cellular oxidative damage.

2. Antitumor mechanism

3. ERα inhibition in breast cancer cells: Kaemprol can downregulate the expression of estrogen receptor α, block estrogen-mediated signaling, and suppress tumor cell proliferation.
4. MEK-MAPK pathway activation: In glioblastoma and lung cancer cells, kaemprol activates the MEK-MAPK signaling pathway, promoting apoptosis. Activation of this pathway leads to caspase cascades and cell cycle blockade, thereby inducing tumor cell death.

5. Regulating cell cycle and apoptosis proteins: Kaemprol modulates the expression of apoptosis-related proteins such as Bcl-2 and Bax, promoting mitochondrial pathway-mediated apoptosis.

6. Anti-inflammatory and other mechanisms
   Kaempol exerts anti-inflammatory effects by inhibiting the NF-κB signaling pathway, reducing the release of pro-inflammatory cytokines such as TNF-α and IL-6. In addition, its regulation of various enzyme activities also contributes to its pharmacological effects across multiple targets.

Druggability evaluation and pharmacokinetics

The druggability parameters of kaempamol indicate that it has certain potential for drug development. A molecular weight of 286.2390 conforms to the Lipinski rule, and a LogP value of 2.0477 indicates moderate lipid solubility, which is beneficial for penetrating the cell membrane. TPSA was 111.1300, slightly above the ideal range (<90 Ų), which may affect its oral bioavailability. Low water solubility (0.1198 mg/mL) limits its absorption in the body, suggesting the need for drug formulations to improve its solubility.

The lower blood-brain barrier penetration capacity suggests that kaemprol is distributed in the central nervous system, but this may reduce central side effects in treating diseases that are not central targets. The hERG channel inhibition test was negative, indicating a low risk of cardiotoxicity. Ames test results showed low genotoxicity risk and good safety.

Pharmacokinetics, physomatol is absorbed slowly after oral administration, and its bioavailability is limited by its low water solubility and first-pass effect. Its metabolism in the body is mainly through phase II reactions in the liver, such as glucuronylation and sulfation, with metabolites being easily excreted. Future research needs to further optimize its pharmacokinetic properties to improve in vivo stability and targeting.

Prospects and outlooks for clinical applications

With its broad pharmacological activity, especially its remarkable effects in antitumor and antioxidant fields, kaempabol demonstrates promising clinical application potential. As a common malignant tumor in women, kaemprol offers a new approach for treating hormone-dependent breast cancer by inhibiting ERα expression. Research on glioblastoma and lung cancer shows that it has potential therapeutic value across various tumor types.

However, the clinical translation of kaempraphenol still faces many challenges, mainly its low water solubility and bioavailability, which limit its efficacy. In the future, drug formulation technologies such as nanocarriers, liposome encapsulation, and eucrystal formation can improve their pharmacokinetic properties. Furthermore, in-depth analysis of its mechanisms of action and molecular targets helps in developing more targeted derivatives or combination drug strategies.

Preclinical research should strengthen systematic evaluation of the safety, toxicology, and pharmacodynamics of kaemprol to promote its entry into clinical trials. By integrating precision medicine concepts, patients suitable for kaemprol therapy are selected to improve the success rate of clinical application.

Conclusion

As a versatile natural flavonoid compound, kaempabol demonstrates broad research and application prospects in fields such as antioxidant, anti-tumor, and anti-inflammatory due to its unique chemical structure and rich bioactivity. By regulating multiple signaling pathways such as the NFE2L2/NRF2 antioxidant pathway and the MEK-MAPK apoptotic pathway, it exerts complex molecular mechanisms and provides valuable research examples for natural product pharmacology.

Although clinical development of kaempabol still faces challenges in pharmacokinetics and formulation technology, with advances in modern drug design and nanotechnology, these bottlenecks are expected to be overcome in the future, enabling its clinical application in the treatment of tumors and other diseases. Systematic and in-depth pharmacological mechanism research and preclinical evaluation will lay a solid foundation for the drug development of kaemprol, promoting it as an important representative in natural product drug development.

In summary, as a safe and effective natural active ingredient, kaempafen deserves continued attention and in-depth exploration in future drug development.