OPC 400 Forte
Grape Seed Extract


Our highly pure OPC grape seed extract 400 contains a full 400mg dose per capsule of OPC derived from Spanish grape seeds. OPC content HPLC-tested by the University of Braunschweig. Ultra pure extraction method using water and edible ethanol. Vegan, no additives (such as magnesium stearate, methanol, or ethyl acetate). 2x120 capsules
  • Naturally sourced: premium wine grape seed extract from Spain
  • High-dose: 400mg pure OPC per capsule
  • Cultivation, processing and extraction of the grapes directly in Spain
  • OPC content confirmed via reliable HPLC testing method by the TU Braunschweig 
  • Ultra-pure grape seed extract with 95%+ total polyphenols
  • High proportion of total proanthocyanidins: 89.72%
  • Best extraction process: gentle extract from water and edible ethanol
  • Free from chemical solvents and residues such as methanol, N-hexane, acetone
  • Vegan, gluten-free, non-GMO
Customize OPC 400 Forte <br/>Grape Seed Extract
2 x OPC 400 Forte Grape Seed Extract   + €0.00

* Required Fields

€32.10 €33.80


Delivery : 1–3 business days

Incl. VAT, excl. Shipping

€215.44 / 1kg

Premium Bioactive Ingredients

  • High-dose: 400mg pure OPC per capsule
  • 100% premium extract of Spanish grape seeds
  • OPC content confirmed via the reliable HPLC test by TU Braunschweig
  • Ultra-pure grape seed extract with over 95% total polyphenols
  • High proportion of total proanthocyanidins: 89.72%
  • Gentle extraction using water and food grade ethanol, free from chemical residues such as methanol, ethyl acetate, acetone and n-hexane

How are we different?

Our OPC 400 is obtained 100% from Spanish grapes and processed directly on site in Spain. The quality of different OPC active ingredients differs significantly, as the actual OPC content varies greatly. Conventional tests such as the DMAC and vanillin test deliver misleading and far too high OPC values here, which are sometimes 400% higher than the actual OPC content. Only HPLC controls can confirm the real OPC content.

Our OPC 400 has been tested by the TU Braunschweig for its actual OPC content and we publish the test results in their entirety. When choosing our raw materials, we pay attention to the highest possible OPC content in order to achieve a correspondingly sufficient dosage as well as the greatest possible purity. Our grape seed extract from white Spanish grapes has a pure content of at least 95% polyphenols, which was specified as the OPC content. Many producers confuse the total polyphenol content with the actual OPC content of a product. Information regarding the OPC content of our product was ascertained via an HPLC laboratory test (the most reliable measuring method) on mono-, di-, tri-, tetra-, penta-, and polymers conducted by the Technical University of Braunschweig: Excluding the monomers which do not belong to the OPCs, the pure OPC content is estimated to be 77.5%. This percentage is the basis for caluculation we use for our capsules. 

Unlike many other OPC supplements, our product is derived using water and edible ethanol without any other chemical solvents. The resulting ultra pure extract is completely natural and has no residues from chemical solvents such as n-hexane, methanol, or acetone. All of our products are guaranteed free from additives such as maltodextrin and peanut powder, which are often mixed into OPC but not required to be disclosed on the label.

For the capsule shells we use custom-made HPMC capsules that, unlike most other HPMC and pullulan capsules on the market, are 100% free from controversial additives such as carrageenans and PEG. We then package this product in environmentally friendly amber glass.


  • Premium active ingredients in their purest form
  • Sourced directly from the world’s best producers
  • Our select raw materials are the basis of all our formulations
  • Complete avoidance of all unnecessary additives and adjuvants
  • Exclusive use of valuable natural ingredients for additives
  • We voluntarily declare all ingredients
  • All extractions performed without the use of chemical solvents
  • Custom production when necessary, in order to achieve the highest possible level of purity
  • Independent laboratory testing available on product pages
  • Raw materials sourced only from premium suppliers who are committed to fair working conditions
  • Amber glass and compostable pouches used for packaging
  • Vegan capsule shells, free from PEG and carrageenans
  • Packaged in the EU according to HACCP, GMP and ISO 22000:2018 standards
  • Stored in non-toxic containers
  • Shipped in mineral oil-free boxes
  • All products guaranteed 100% free from magnesium stearate, silicon dioxide, nanoparticles (no legal opportunism), genetic engineering, artificial colours and flavours, titanium dioxide and added sugar & sweeteners


OPCs (Oligomeric Proanthocyanidins) named also as vitamin P, are a group of substances belonging to the flavonols, which consist of polymers of catechins and epicatechins. Proanthocyanidins are present in a whole range of fruits and plants, including the seeds and skins of grapes, in berries and citrus fruits, but also in the protective bark layer of trees.

The various proanthocynidins are categorised by their number of units (e.g. monomer for one unit, dimer for two). The exact definition of OPC is unclear and may include only di- to tetramers, di- to pentamers, di- to hexamers, or even all proanthocyanidins except monomers.

For a long time, only the dimers, i.e. consisting of two, and the trimers, consisting of three units, were considered to be bioactive. However, this has since been disproven, allowing a complex interaction of all components of the grape seed extract (including the polymeric proanthicyanidins such as hexamers and heptamers) to be used. OPC compounds are contained in large quantities, especially in pine bark and grape seeds, in which the individual proanthocyanidins differ from each other both in form and in their effect. There is also a notable amount of vital proanthocyanidin-B3-3'-O-gallate in grape seed extract.


Recommended Dosage

Take 1 capsule (400mg OPC) with 200ml water at mealtimes.

Food Supplement

Do not exceed the recommended dose. Nutritional supplements cannot replace a balanced and varied diet. Keep out of reach of children.


Store in a cool, dry place away from direct sunlight and heat.


Ingredients: Grape Seed Extract (from Spanish Grapes).
Capsule shells: Hydroxypropyl Methylcellulose.
Contains: 120 capsules

Ingredients per Daily Dose (1 Capsule) % NRV*
Grape Seed Extract 504.5mg -
of which pure OPC 400mg -

*% Nutrient Reference Value

Per capsule: 400mg OPC
In total: 48.000mg OPC / Glas

Product Details

German Pharmaceutical Number (PZN) 14291886
Origin Spain

In-house production in Europe, bottling and encapsulation in the EU according to HACCP, GMP / ISO 22000:2018 standards
Finished products packaged in amber glass jars, and stored in non-toxic containers
Shipping in mineral oil-free boxes

Capsules Plant-based cellulose (HPMC). Vegan
Premium HPMC quality: Free from controversial additives such as carrageenans and PEG
Packaging Amber glass jar to protect against light and oxidation (free from plasticisers and BPA)
To Reuse Remove product label by soaking the jar in warm water for 5 minutes. Glue residue can be removed with dish soap.

Laboratory Tests

The purity of our formulas is important to us. This is why we have both our raw ingredients as well as our finished products extensively tested by independent laboratories to confirm purity and active ingredient content. Here, we have provided the results of some of the tests carried out on this product.

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Our Philosophy

For thousands of years, cultures all over the world have been using medicinal plants and nutritious foods to naturally foster and maintain vitality and good health.

With our products, we try to emulate this ancient wisdom as much as possible.

Consequently, our philosophy is simple: everything we do meets the highest standards of quality and purity; our focus is on organic and natural ingredients.

We follow this philosophy with meticulous care on all levels and down to every last detail.

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