Chinese yam (Dioscorea polystachya)

Chinese yam: botanical (rhizome).

Chinese yam testing at Vanguard Laboratory: identity, purity and quantity $250 per sample, with results in 3 to 5 business days.

Structure

Marker compound: 2D structure drawn from the PubChem record (CID 204).

Compound data

Botanical source

Dioscorea polystachya Rhizome

Marker compounds

allantoin

Basis

total or named markers, as your specification states

Type

Botanical (rhizome)

Structure and names

Marker compounds: allantoin (CAS 97-59-6)

How Vanguard tests Chinese yam

Method for the $250 identity, purity and quantity test: Chromatographic marker-compound assay, with detection selected for the compound, against a reference standard, with results in 3 to 5 business days.

The USP Herbal Medicines Compendium monograph (proposed for development) covers identity by HPTLC fingerprint and an assay of marker compounds by HPLC.

What's reported

Marker compounds, as % w/w on the basis your specification states
Quantity, against the label claim
Identity, reported as match or no match against the reference standard
With monograph testing (quoted): the monograph’s tests against its limits

Tests and prices

Purity and quantity

$250

Chromatographic purity and mg per unit by the method matched to the compound, identity against a reference standard. 1 unit.

Raw powder purity

$200

Chromatographic purity on bulk powder. 50 mg.

Add-on tests

Add-on test	Price
Identity and impurities
FTIR identity	$90
CHNS elemental analysis (carbon, hydrogen, nitrogen, sulfur)	$125
Chiral purity (where a chiral method exists; new methods quoted)	$250
Water, solvents and salt form
Water content by Karl Fischer	$60
Residual solvents	$150
Counterions: chloride, acetate and TFA	$70
Assay
Assay, % w/w (with raw powder purity; $250 together)	+$50
Metals and conformity
Heavy metals: arsenic, cadmium, chromium, mercury and lead	$150
Conformity: purity and quantity on more units from the same lot	$100 per extra unit

10% off for 10 or more samples.

Need something else? Other tests are available on request.

Sample amount and turnaround

Purity and quantity is $250 per sample (1 unit) and raw powder purity is $200 for 50 mg, with results in 3 to 5 business days. Send the material sealed and labeled, with the label claim and the form it contains.

Salts, forms and compendial references

Dioscorea polystachya Rhizome
Tell us the salt or form the label states, so quantity is reported on the same basis.

Questions about Chinese yam testing

Is the $250 test the same as USP monograph testing?

No. The $250 test covers identity, purity and quantity by a chromatographic assay, with detection selected for the compound.

Is Chinese yam a source of diosgenin?

Chinese yam rhizome contains only small amounts of diosgenin-type saponins compared with the Dioscorea species grown for diosgenin. Products labeled as wild yam are often other Dioscorea species.

What form do samples usually arrive in?

Usually dried rhizome slices, powder or extract. The rhizome is high in starch, which is taken into account during extraction.

Sources

https://pubchem.ncbi.nlm.nih.gov/compound/204

Identity facts from the USP monograph header for this compound.

Order

Start an order online, or send the compound name and the tests you need for a quote.

All research compounds