Catechins are plant-derived flavan-3-ols most abundantly found in green tea. Nutraceutical manufacturers value catechins for their antioxidant activity and wide-ranging formulation into capsules/tablets, beverages and topical applications. In this guide, we discuss catechin chemistry, major natural sources, analytical/quality control best practices, formulation and stability challenges, and more.
What Are Catechins?
Catechins are flavan-3-ols, a subclass of flavonoids that are synthesized as secondary metabolites in plants. These polyphenolic compounds are characterized by their unique chemical structure featuring two polyphenolic aromatic rings with hydroxyl groups. Major catechins relevant to nutraceuticals include:
- (−)-Epigallocatechin gallate (EGCG)
- (−)-Epigallocatechin (EGC)
- (−)-Epicatechin gallate (ECG)
- (−)-Epicatechin (EC)
Galloylation (attachment of gallic acid) and stereochemistry define functional differences between these molecules. Catechins are chemically labile: they oxidize, epimerize (especially under heat), and can polymerize to form theaflavins/thearubigins in processing. These compounds are not merely plant pigments; many colorless flavonoids like catechins play crucial roles in plant defense and offer significant benefits when incorporated into human nutrition. The reported beneficial effects of catechins include antioxidant activity, UV protection activity, antibacterial activity, anti-allergic and anti-inflammatory activity, antiviral and anticancer activity, etc.
Learn More About the Benefits of Catechins for Human Health
Natural Sources of Catechins: From Tea to Beyond
While tea is the most concentrated source, catechins are distributed throughout the plant kingdom.
Table: Catechin Content in Common Dietary Sources
| Source | Notable Catechins Present | Concentration Level |
|---|
| Green tea | EGCG, EGC, ECG, EC | High (15-30% dry weight) |
| Red wine | Catechin, Epicatechin | Moderate |
| Cocoa/Chocolate | Catechin, Epicatechin | Moderate |
| Apples | Catechin, Procyanidins | Low to Moderate |
| Strawberries | Catechin, Epicatechin | Low to Moderate |
Population daily intake of flavonoids is highly variable depending on diet and other lifestyle factors, but the average range is reported to be 23-1000 mg/day. In tea drinkers, about 55% of dietary catechin intake is derived from tea consumption, while in Mediterranean diets featuring wines and fresh produce, about 100 mg of catechins and procyanidins is consumed daily.
Catechin Ingredients from Alfa Chemistry
At Alfa Chemistry, we provide a comprehensive portfolio of high-purity, well-characterized catechin compounds to support your advanced research and product development. Our products are trusted by nutritional supplement manufacturers and formulators worldwide for their consistency, quality, and reliability.
| Product Name | Brief Technical Note | Common Applications | Price |
|---|
| Epigallocatechin Gallate (EGCG) | Most-studied catechin and common standard for green-tea extracts. | High-potency supplements, topical antioxidants, clinical research | Inquiry |
| Epigallocatechin (EGC) | Non-galloylated epigallocatechin; precursor to EGCG in green tea. | Comparative catechin studies, assay standards | Inquiry |
| Epicatechin Gallate (ECG) | Galloylated epicatechin; antioxidant polyphenol found in tea & cocoa. | Antioxidant blends, research on lipids & metabolism, high-potency nutraceuticals | Inquiry |
| Epicatechin, (-)- (EC) | Naturally occurring (−)-epicatechin; common in cocoa and tea. | Cardiometabolic research, nutraceutical ingredient, assay standard | Inquiry |
| Catechin, Dl- | Racemic catechin mixture for method development and research. | Analytical method development, calibration standards | Inquiry |
| Gallocatechin | Non-galloylated gallocatechin; green-tea constituent. | Research into bioactivity, comparative catechin profiling | Inquiry |
| Catechin Gallate | Common galloylated catechin found in Camellia sinensis. | Standardization marker, antioxidant blends, topical antioxidants | Inquiry |
| Theaflavine-3-Gallate | Theaflavin conjugate formed during black-tea oxidation; pigmented polyphenol. | Functional beverage color/stability testing, analytical reference | Inquiry |
| Theaflavine-3,3'-Digallate | Digallate theaflavin with strong antioxidant capacity and pigment properties. | Beverage formulation research, stability studies, pigment profiling | Inquiry |
| Gallocatechin Gallate | Gallocatechin with galloyl group — high antioxidant potential. | High-potency supplement blends, research on oxidative stress | Inquiry |
| Theaflavine | Core theaflavin (non-galloylated) from tea oxidation — pigment and antioxidant. | Beverage R&D, colorants, comparative polyphenol research | Inquiry |
| Eleagnin Hcl, Dl- | Salt form of a plant alkaloid used as a reference or research intermediate. | Analytical standards, phytochemical research | Inquiry |
| Tetrahydrolinalool | Terpenoid used as fragrance or analytical standard; relevant in botanical matrices. | Flavor masking, sensory studies, botanical extract profiling | Inquiry |
| Tartaric Acid, L- | Food-grade acidulant and chelator used in stabilization and pH control. | Beverage pH control, chelation to improve catechin stability | Inquiry |
Typical Use Levels & Formulation Examples
The following values are typical ranges used in industry formulations for reference only – adjust as needed per regulatory guidance, safety data and target claims.
Dietary supplement capsule/tablet: 100–500 mg green tea extract per serving; EGCG-specific formulations commonly deliver 50–300 mg EGCG per serving.
Functional beverages: 50–200 mg total catechins per serving (formulation dependent).
Topical: 0.5–5% w/w catechin fractions (product-dependent; stability and irritation testing required).
Formulation Considerations & Strategies with Catechins
In practice, catechins are considered to have challenges with respect to stability, aqueous solubility, and organoleptic characteristics. In particular, they can be chemically unstable and have a strong taste. A series of strategies can be applied in formulation development to address these issues.
Solid Oral Formats (Capsules/Tablets):
- Use antioxidants (ascorbic acid, tocopherols) and chelators (EDTA) as stabilizers.
- Microencapsulation (spray-dry with maltodextrin, gum arabic) to mask taste and improve stability.
- Enteric coating protects from stomach acid and masks bitterness, but is also a useful tool for achieving a targeted intestinal release
- High-fill excipients, and low-compression settings for tablets to avoid heat from compression causing epimerization during tableting process.
Liquids & Beverages:
- Catechins are susceptible to oxidation and color change; low pH can help stability in beverages, but low pH may increase astringency.
- Use oxygen-barrier packaging, inert headspace, and include antioxidants.
- Consider complexation (e.g., cyclodextrins) to increase solubility and mask bitterness.
Our Formulation Development Solutions
Analytical & Quality Control (QC)
Industry standard QC approaches:
- Identity & assay: HPLC with UV detection is the industry workhorse for catechin profiling and quantitation (EGCG, EGC, ECG, EC). HPLC-MS offers additional specificity for trace analysis.
- Purity: TLC/HPLC to detect major impurities and residual theaflavins.
- Moisture / loss on drying: to control degradation risk.
- Residual solvents: GC analysis following ICH Q3C.
- Heavy metals: ICP-MS or AAS for lead, cadmium, mercury, arsenic, etc.
- Microbiology: Total aerobic count, yeast & mold, E. coli, Salmonella.
- Pesticide residues: multi-residue screening (GC-MS/MS and LC-MS/MS).
- Stability testing: accelerated and long-term stability to monitor assay, color, and moisture changes.
- Certificate of Analysis (CoA): supply full CoA with batch ID, assay, contaminants, and date.
Recommended routine checks: HPLC catechin profile, moisture, heavy metals, residual solvents, microbial tests, and pesticide screen. For high-value EGCG concentrates, include epimerization and degradation product monitoring.
More Catechin-Related Products
References
- Isemura, Mamoru. Molecules 24.3 (2019): 528.
- Bae, Joonseo, et al. Biomedical Dermatology 4.1 (2020): 8.
Our products and services are for research use only and cannot be used for any clinical purposes.
