PSB
Pterostilbene
Key Specifications
| CAS Number | 537-42-8 |
| Purity | ≥98.0% |
| Molecular Formula | C₁₆H₁₆O₃ |
| Molecular Weight | 256.30 g/mol |
| Appearance | White to off-white powder |
| Solubility | Slightly soluble in water; soluble in ethanol |
| Storage | Room temperature, protect from light |
| Shelf Life | 24 months |
CAS 537-42-8
What Is PSB?
Pterostilbene is a naturally occurring dimethylated stilbenoid and a structural analog of resveratrol, identified by CAS No. 537-42-8, molecular formula C16H16O3, and molecular weight 256.30 g/mol. Chemically it is trans-3,5-dimethoxy-4'-hydroxystilbene, in which two of resveratrol's phenolic hydroxyl groups are replaced by methoxy groups, improving lipophilicity and metabolic stability relative to resveratrol. It occurs naturally in trace amounts in blueberries and other Vaccinium berries, grape leaves, and Pterocarpus marsupium heartwood. Because natural extraction yields are too low for commercial supply, bulk-scale material is typically produced industrially via a biosynthetic/enzymatic route: engineered microbial fermentation generates a resveratrol precursor, which is then enzymatically O-methylated to pterostilbene, followed by extraction, crystallization, and purification.
Other Names
Key Features
High-Purity Assurance
Each batch is manufactured to ≥98.0% purity and verified by HPLC before release, giving formulators a consistent, dependable active for finished-product dosing.
Controlled Bio-Enzymatic Production
Produced on PathGene's synthetic-biology platform via fermentation-derived precursor and enzymatic O-methylation, with in-process controls at every stage to ensure batch-to-batch consistency.
Fine White Powder Form
Supplied as a white to off-white powder with uniform particle size, offering good flow and blend uniformity for tableting, capsule filling, and premix applications.
Full Contaminant Screening
Every lot is screened for heavy metals (Pb, As, Hg, Cd) and microbial limits, with a COA and supporting test reports available on request.
Flexible Bulk & OEM Supply
Available in flexible order quantities from sample to bulk kilogram/ton scale, with OEM/private-label formatting, custom packaging, and documentation support.
| Molecular Formula | C₁₆H₁₆O₃ |
| Molecular Weight | 256.30 g/mol |
| Appearance | White to off-white powder |
| Solubility | Slightly soluble in water; soluble in ethanol |
| Storage Condition | Room temperature, protect from light |
| Shelf Life | 24 months |
| Grade 1 | Supplement Grade · ≥98.0% · COA |
End-Product Applications
Mechanism & Benefits
Methylated resveratrol analog with superior bioavailability. Anti-inflammatory, anti-microbial, blood glucose regulation.
Packaging Options
100 g 500 g 1 kg
Lead Time
7–10 business days
Minimum Order
100 g
Custom Packaging
Custom packaging (foil bags, HDPE drums), GMP labeling, and export documentation are available. Contact us for specifics.Certifications
ISO
ISO
Manufacturing Process
Strain & Enzyme System Development
An engineered microbial host strain is constructed carrying the biosynthetic gene cassette (tyrosine ammonia-lyase, coumarate-CoA ligase, stilbene synthase) together with a resveratrol O-methyltransferase (ROMT), enabling downstream conversion to pterostilbene.
Fermentation to Resveratrol Precursor
The engineered strain is fermented under controlled conditions, converting a tyrosine/p-coumaric acid feedstock through the stilbene synthase pathway to accumulate resveratrol as the key intermediate.
Enzymatic Bio-Methylation
The resveratrol intermediate undergoes SAM-dependent, two-step enzymatic O-methylation catalyzed by ROMT, selectively installing methoxy groups at the 3,5-positions to yield pterostilbene while preserving the 4'-hydroxyl.
Cell Harvest & Extraction
Fermentation broth is harvested and the biomass is disrupted; pterostilbene is extracted from the cell mass and clarified broth using solvent extraction.
Purification & Decolorization
Crude extract is purified through chromatographic/adsorption separation and activated-carbon decolorization to remove residual pigments, proteins, and process-related impurities.
Crystallization
The purified concentrate is crystallized under controlled cooling to obtain pterostilbene crystals of defined polymorphic form and particle characteristics.
Drying & Micronization
Crystals are vacuum-dried to the target moisture specification and milled/sieved to achieve a uniform, free-flowing fine powder.
QC Testing & Packaging
Finished powder is tested against full release specifications (assay, heavy metals, microbial limits) before being packed under moisture-protective conditions for shipment.
Quality Specifications
| Test Item | Specification | Result |
|---|---|---|
| Appearance | White to off-white crystalline powder | White to off-white powder, conforms |
| Odor | Characteristic, odorless to faint | Odorless, conforms |
| Identification (HPLC retention time) | Matches reference standard | Conforms |
| Assay (HPLC) | ≥98.0% | 98.5% |
| Melting point | 96.0-99.0 °C | 97.2 °C |
| Loss on drying | ≤0.5% | 0.2% |
| Particle size (80 mesh pass rate) | ≥95% | 98% |
| Lead (Pb) | ≤2 mg/kg | <1 mg/kg |
| Arsenic (As) | ≤1 mg/kg | <0.5 mg/kg |
| Mercury (Hg) | ≤0.1 mg/kg | <0.05 mg/kg |
| Cadmium (Cd) | ≤1 mg/kg | <0.5 mg/kg |
| Total plate count | ≤1000 CFU/g | <100 CFU/g |
| Yeast & mold | ≤100 CFU/g | <10 CFU/g |
| Pathogens (E. coli / Salmonella) | Negative/25g | Negative |
Purity & Assay Method
Purity is determined by reversed-phase HPLC against a certified pterostilbene reference standard, typically with UV detection around 306 nm, and reported on an as-is (non-volatile) basis. Buyers should request the full Certificate of Analysis for each lot, confirm the exact HPLC method (column, mobile phase, wavelength) used, and specify any additional identity confirmation (e.g., IR or mass spectrometry) required for their internal qualification.
Solubility & Formulation
Pterostilbene is only slightly soluble in water but readily soluble in ethanol and most food-grade organic solvents, consistent with its lipophilic dimethoxy-stilbene structure. For aqueous or beverage formulations, buyers commonly improve dispersibility using co-solvents (ethanol, propylene glycol), surfactant/emulsifier systems, cyclodextrin complexation, or micro/nano-emulsification and self-emulsifying delivery formats. For solid-dose formats such as tablets, capsules, and powders, the material can generally be used directly with standard excipients and appropriate particle-size control to support blend uniformity.
Available Product Forms
Bulk PSB Powder
High-purity raw powder for supplement factories, research organizations, ingredient distributors, and contract manufacturers.
PSB Capsules
Custom capsule strength, shell material, bottle count, excipients, and label design for private-label brands.
PSB Tablets
Tablet formulation, granulation, compression, coating, bottle packaging, and custom labeling support.
PSB Powder Blends
PSB can be blended with complementary actives (antioxidants, other longevity ingredients, vitamins, minerals) per customer formula.
How is the ≥98.0% purity of PathGene's pterostilbene verified?+
Each batch is tested by HPLC against a certified reference standard and reported on the Certificate of Analysis (COA) issued with every shipment; buyers are welcome to request the COA and supporting chromatogram before or after purchase.
What production method is used to manufacture this pterostilbene?+
It is produced on PathGene's synthetic-biology and enzymatic production platform: engineered microbial fermentation generates a resveratrol precursor, which is then converted to pterostilbene via enzymatic O-methylation, followed by extraction, purification, and crystallization.
Is pterostilbene water soluble, and how should I formulate with it?+
Pterostilbene is only slightly soluble in water but soluble in ethanol; for aqueous applications we recommend co-solvents, emulsification, or cyclodextrin complexation, while solid-dose formats can typically use the powder directly. See our solubility/formulation guidance for more detail.
Can I request a free sample before placing a bulk order?+
Yes, small evaluation samples are available on request for qualified B2B buyers to verify appearance, solubility, and analytical results before committing to a bulk purchase.
Do you support third-party testing of this ingredient?+
Yes, buyers may send retained samples to an independent third-party laboratory of their choice for verification of purity, heavy metals, or microbial limits, and we can provide historical COAs to support the process.
Do you offer OEM or private-label services for finished products containing this ingredient?+
Yes, PathGene supports OEM/private-label formatting, including custom blends, encapsulation/tableting coordination with partner facilities, and customer-branded packaging and documentation.
What packaging options are available, and what is the MOQ?+
Standard packaging is in moisture-proof, light-protected bags/drums (e.g., 1 kg, 5 kg, 25 kg), with custom packaging available for larger or OEM orders. MOQ and pricing depend on order volume and specification requirements — please contact us for a formal quotation.
Why Choose PathGene
- Direct China manufacturer supply — factory pricing, no middleman
- Batch-specific COA & full traceability on every shipment
- In-house R&D + synthetic biology / enzymatic production platform
- Free sample for qualified B2B buyers before commercial order
- Flexible MOQ — from lab-scale trial to ton-scale commercial supply
- One-stop OEM/private-label support for finished dosage forms
- Worldwide shipping by courier, air freight, and sea freight
OEM & Private-Label Services
- ·Custom capsule manufacturing
- ·Custom tablet manufacturing
- ·Powder blending & custom formulation
- ·Private-label bottles, pouches & labels
- ·Small trial orders
- ·Bulk commercial production
- ·Export documentation
- ·Third-party laboratory testing
Documents Available
- ·Certificate of Analysis (COA)
- ·Product specification sheet
- ·Material Safety Data Sheet (MSDS)
- ·Manufacturing flow chart
- ·HPLC test report
- ·Heavy-metal test report
- ·Microbiological test report
- ·Non-GMO / allergen statement
- ·Country-of-origin documentation
- ·Packing list & commercial invoice
Certificate availability should be confirmed with our sales team before ordering.
Sample Certificate of Analysis
PathGene Biotech Co., Ltd.
南京派琪生物科技有限公司
CERTIFICATE OF ANALYSIS
Layout example — not an issued batch record
Product Name
PSB
CAS No.
537-42-8
Batch No.
PG-SAMPLE-000000
Packaging
Issued upon order confirmation
| Test Item | Specification | Result |
|---|---|---|
| Appearance | White to off-white crystalline powder | White to off-white powder, conforms |
| Odor | Characteristic, odorless to faint | Odorless, conforms |
| Identification (HPLC retention time) | Matches reference standard | Conforms |
| Assay (HPLC) | ≥98.0% | 98.5% |
| Melting point | 96.0-99.0 °C | 97.2 °C |
| Loss on drying | ≤0.5% | 0.2% |
| Particle size (80 mesh pass rate) | ≥95% | 98% |
| Lead (Pb) | ≤2 mg/kg | <1 mg/kg |
| Arsenic (As) | ≤1 mg/kg | <0.5 mg/kg |
| Mercury (Hg) | ≤0.1 mg/kg | <0.05 mg/kg |
| Cadmium (Cd) | ≤1 mg/kg | <0.5 mg/kg |
| Total plate count | ≤1000 CFU/g | <100 CFU/g |
| Yeast & mold | ≤100 CFU/g | <10 CFU/g |
| Pathogens (E. coli / Salmonella) | Negative/25g | Negative |
Conclusion: Conforms to internal quality specifications
The COA issued with your order will carry the actual batch number, manufacture/test dates, and QC signature.
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Interested in PSB?
Our R&D team will respond to your inquiry or sample request within 24 hours.
