The same name does not guarantee the same material. Once it is a powder its origin is invisible, and all that remains is what the specification says in words. Our sourcing begins by establishing what those words actually refer to.
1. Identifying the substance — and where CAS stops helping
The first task is identification. Our catalog states a CAS number for 308 items. But a CAS number alone is not enough in two situations.
Same substance, different CAS — the salt form
Change the salt and the CAS number changes with it. The three forms of L-carnitine we carry each have their own.
| Form | CAS | Practical note |
|---|---|---|
| L-Carnitine (free base) | 541-15-1 | Hygroscopic; needs care after opening |
| L-Carnitine fumarate | 90471-79-7 | Carries the fumarate’s molecular weight |
| L-Carnitine tartrate | 36687-82-8 | Relatively stable as a powder |
What matters is that the same charged weight delivers a different amount of L-carnitine. We confirm whether the specification reads “as the salt” or “as L-carnitine”, and when a form changes we redesign the quantity on the compound basis rather than carrying it across.
Same CAS, different material — source and grade
The reverse also happens. Inulin from chicory and from agave share a CAS. Microcrystalline cellulose and cellulose are the same family, but a different specification means a different fit for the application. A CAS number identifies a substance, not a product.
2. Fixing the content basis — what the percentage is of
This is where rework most often starts. The same “x%” implies a different material quantity depending on what it is a percentage of. Four examples from items we actually carry:
| Material | How the basis splits | Size of the gap |
|---|---|---|
| L-Carnitine | as the salt / as L-carnitine | the counter-ion’s molecular weight |
| Lutein | free form / ester form | the fatty acid’s molecular weight |
| Bilberry extract | anthocyanins 36% / anthocyanidins 25% | about 1.4× |
| Glucosylceramide | material weight / component amount | per the content percentage |
Bilberry gives the clearest arithmetic. A specification states “anthocyanins 36.0% min.” and “anthocyanidins 25.0% min.” side by side — glycosides with the sugar attached, and aglycones with it removed. Both are correct for the same lot. The notified ingredient is “bilberry-derived anthocyanins”, so you calculate with 36%; divide by 25% and you overestimate the extract needed by about 1.4×.
Telling us “this component amount, in this dosage form” rather than “this material” lets us put the basis on a common footing before proposing candidates.
3. Concentration ratios are not a standard
Plant extract names often carry “20:1” or “50× concentrated”. This is a conventional way of expressing the ratio of plant material to extract, and no public standard governs it. The figure looks like a specification but is not one.
What can actually be compared is the marker compound content. Two materials both labelled “20:1” differ if the solvent, the plant part or the drying method differ. We treat the ratio as part of the name and use the marker specification as the basis for selection.
4. Origin and manufacturer — decided before the powder
The same plant differs by origin and by part. Root or leaf, when harvested, where dried. None of this can be confirmed once it is a powder, so it has to be settled at the sourcing stage.
- Origin — at country and region level; our catalog carries origin as a classification
- Plant part — root, leaf, fruit, seed, bark. Composition differs by part
- Manufacturer — where extraction, drying and milling were done; certifications held
- Distinguishing close relatives — bilberry (Vaccinium myrtillus) and blueberry (Vaccinium spp.) are one of many such pairs
5. Small lots and trials
Development usually starts with a small quantity. We take enquiries from trial and small-lot volumes. It helps to settle the scale-up conditions at the same time: whether a single lot can cover the run, continuity of specification across lots, and lead time.
Sourcing checklist
- CAS number — down to the salt form and hydrate
- Content basis — what the percentage is of; the factor and its justification if converted
- Marker compound specification — not the concentration ratio
- Origin, plant part, manufacturer
- Analytical method — compendial or in-house
- Lot-to-lot variation — the observed distribution, not just the specified minimum
- Storage conditions and shelf life
- Small-lot availability and lead time
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