Cyperus rotundus Extract 6% Stilbenes

The dried rhizome of Cyperus rotundus, the nutgrass or purple nutsedge, is the only part used in this extract, and the leaf, stem and the edible tubers of the related Cyperus esculentus are excluded. Ethanol extraction takes up the stilbenes and phenolic compounds of the rhizome, and the concentrate is dried to a light brown powder.

The single grade is 6% stilbenes by HPLC, counted as scirpusin A, scirpusin B and piceatannol. The powder is 80 mesh and insoluble in water. It fits capsules, tablets and blends in which a stilbene-rich rhizome fraction is the design target.

SKU: BOT-STX-0137 Category: Standardized Extracts Tags: Ethanol Extracted, Nut Grass, Polyphenols, Root & Rhizome, Standardized Extracts, Stilbenes

Stilbene Standardization & Grades

Stilbenes are a group of phenolic compounds built on a two-ring skeleton joined by an ethylene bridge, of which resveratrol is the best known. In Cyperus rotundus rhizome the relevant members are piceatannol, a hydroxylated analog of resveratrol, and its dimers scirpusin A and scirpusin B. The botanical entity is Cyperus rotundus L., and the extract is standardized to this group because it is the defining non-volatile phenolic fraction of the rhizome, in contrast to the sesquiterpene essential oil that is the other well-known part of the plant.

The grade is a single point at 6%, so there is no grade table. The figure is the sum of the three named stilbenes by HPLC, and it does not include the sesquiterpenes such as cyperene and alpha-cyperone, which are volatile and largely absent from a dried ethanol extract. Cyperus is also supplied as a 10:1 ratio extract with no marker figure, the Cyperus Rhizome Extract Powder, and as milled rhizome, the Cyperus Root Powder. The standardized extract is the row to use when a stilbene figure has to appear in the specification of the Cyperus rotundus extract.

Stilbene Analysis & Purity Risks

HPLC separates piceatannol, scirpusin A and scirpusin B on a reversed-phase column and quantifies the peaks against reference standards, with UV detection at a wavelength where the stilbene chromophore absorbs strongly. The result is the sum of the three named compounds. A UV total would count other phenolics, and a gravimetric polyphenol figure would count tannins as well, so neither can be converted into the HPLC sum.

For identity, the fingerprint of the rhizome is read beside the sum. The three stilbene peaks, together with flavonoid glycosides and phenolic acids, form the pattern that is characteristic of Cyperus rotundus rhizome. The ratio of the dimers to piceatannol shows whether the material has been exposed to oxidation, because stilbene dimers form and break down as the extract ages.

Purity risks follow from the botanical group. The genus is large, and several sedges are traded as nutgrass, among them the edible tiger nut Cyperus esculentus, whose tubers are starch-rich and low in stilbenes. The stated species and the stated rhizome part are therefore part of the identity. A figure of 6% stilbenes is also a statement about the sum of three compounds, and a lot with the same percentage built on a different balance of the three may behave differently in a formulation.

Sample preparation uses a polar organic solvent and a short extraction time, because stilbenes with catechol groups oxidize in solution. Samples are protected from light and injected promptly, and an antioxidant such as ascorbic acid is sometimes added to the extraction solvent.

Raw material handling also matters. The rhizome is dug, cleaned of roots and soil, and dried, and some traditional processing steps fry or steep it in vinegar, which changes the balance of volatile and non-volatile constituents. The processing state of the starting rhizome is therefore part of the lot history.

Typical Specifications

Specification Item	Product Information
Latin Name	Cyperus rotundus
Plant Part	Root & Rhizome
Processing	Ethanol Extraction
Compound Class	Polyphenols
Common Name	Nutgrass, Purple Nutsedge, Xiang Fu
Ingredient Type	Standardized Extract
Marker Compound(s)	Stilbenes (scirpusin A, scirpusin B, piceatannol)
Primary Grade	6% Stilbenes (HPLC)
Appearance	Light Brown powder
Solubility / Dispersibility	Insoluble in Water
Quality Parameters
Moisture (LOD)	≤5.0%
Total Ash	≤5.0%
Particle Size	80 mesh
Heavy Metals	Lead ≤2 ppm · Arsenic ≤1 ppm · Cadmium ≤1 ppm · Mercury ≤0.1 ppm
Microbiology	TPC ≤1,000 cfu/g · Yeast & Mold ≤100 cfu/g · E. coli Negative · Salmonella Negative/25 g
Shelf Life	24 months in unopened original packaging, cool and dry storage

Applications by Grade

6% Grade for Standard Capsules

The 6% grade of Cyperus rotundus extract fills two-piece capsules at a moderate weight. The powder is fine, slightly sticky and aromatic, so use a flow agent, fill in a dry room and seal the capsules in a desiccated bottle to protect the stilbenes from moisture.

6% Grade in Tablet Blends

Tablets of the 6% grade need a dry binder and a lubricant, and a film coat covers the earthy, bitter taste of the rhizome. Check hardness and disintegration after storage, because the catechol stilbenes darken tablets that take up moisture.

6% Grade in Sachet Premixes

Sachets dilute the 6% grade with a bulking carrier so that the filler can weigh an accurate dose. The extract is insoluble in water, so the label should call for stirring, and a fine grind avoids visible specks in the cup.

6% Grade in Stick-Pack Drink Powders

Stick packs pair the 6% grade with cocoa, coffee or spiced flavors that cover its earthy character. The cup is hazy and brown, and a light-protective laminate protects the stilbenes from bleaching during storage and transport.

6% Grade in Lipid-Based Fills

Where a liquid or semi-solid capsule is wanted, the 6% grade is dispersed in an oil carrier. Mill it fine first and keep the fill under gentle agitation during dispensing, and choose an antioxidant-stabilized oil.

6% Grade for Contract Blending

Contract blenders place the 6% grade in multi-ingredient powders where a rhizome matrix is wanted. The woody scent of the rhizome lingers on mixer paddles, so dedicated scoops and a dry purge between runs protect milder products that follow. A short clean-down note in the batch record helps trace the product order.

Technical & Quality Considerations

Cyperus rotundus extract is a light brown powder with a woody, faintly sweet, earthy odor. It is insoluble in water, so a liquid format needs a suspension system or a lipid carrier. The stilbenes dissolve in ethanol and in lipid phases but hardly in water, which is why a lipid dispersion gives better uniformity than an aqueous mix.

Piceatannol and the scirpusins carry catechol groups, which oxidize in air, light and the presence of metal ions. The powder darkens with time and turns gray to olive on contact with iron, so stainless contact surfaces, low-iron fillers and light-protective packaging are the practical countermeasures. Oxygen-barrier liners and nitrogen flushing of the drum slow the change.

Scale-up begins with passing the rhizome extract through a fine screen and premixing it with part of the carrier. Drums stay sealed, cool and dark, with a desiccant liner in humid regions. Dust control follows from the fine, tinting powder, so charge the extract through a closed system and wipe balances after each weighing.

Formulation with other ingredients needs a short trial. Alkaline minerals and strongly basic buffers accelerate stilbene oxidation, and acidic, antioxidant-rich bases hold the shade better. An accelerated stability study at elevated temperature shows early whether a combination is sound.

Packaging & Commercial Supply

Essencefield supports product evaluation, formulation trials, commercial orders, and ongoing ingredient supply. Packaging, storage, and shipping arrangements are determined by product characteristics, order quantity, stability requirements, and destination-market needs.

Supply Item	General Information
Sample	Available upon request for formulation, testing, and supplier evaluation
Order Quantities	100 g · 1 kg · 5 kg · 25 kg · 100 kg · 500 kg · Bulk
Sample Lead Time	Typically 5–7 days after sample confirmation
Production Lead Time	Typically 15–30 days after order and specification confirmation
Packaging	Suitable protective inner packaging with bags, cartons, drums, or other appropriate outer packaging
Storage	Store in tightly sealed, suitable protective packaging in a cool, dry environment. Protect from moisture, heat, and direct sunlight. Specific storage conditions follow the approved product specification.
Documentation	COA · Product Specification · TDS · SDS · Applicable declarations (as applicable)

Final order quantities, lead times, packaging, documentation, and shipping arrangements are confirmed according to the selected product and commercial requirements.