Identification of "genuine and counterfeit saponins" in Tribulus terrestris extract
The key to distinguishing between "genuine and counterfeit saponins" in *Tribulus terrestris* extract lies in establishing a comprehensive evaluation system encompassing "raw material traceability, component testing, process verification, and practical validation."
Release time：
2026-01-09
Source：
一、First, let's clarify: the core characteristics of *Tribulus terrestris* "true saponins"
1.The only ingredient is the dried, mature fruit of the Tribulus terrestris plant (family Zygophyllaceae).
The only legitimate source for Tribulus terrestris extract is "the dried, mature fruit of the plant Tribulus terrestris L. (family Zygophyllaceae)." The dried material must have a moisture content of ≤12%—only saponins extracted from this type of raw material possess definite efficacy and activity.
2. Active ingredients are clearly defined: contains characteristic saponin monomers, not just "general total saponins."
Core active monomer：The main components include diosgenin, hecogenin, and sarsasapogenin, which are key to achieving the "testosterone regulation and liver protection" effects; in high-quality extracts, the diosgenin content is usually ≥0.2% (HPLC detection).
3. Process compliance and controllability: Low-temperature extraction + purification and enrichment, with no harmful residues.
The extraction process of genuine saponins must ensure both "activity retention and purity improvement": typically, "ethanol reflux extraction + macroporous resin adsorption purification" is used, which effectively enriches the saponin components and removes impurities such as polysaccharides and tannins. The final product meets national standards in terms of solvent residue and heavy metal content, and is free of harmful impurities.
二、Three common methods used to create "fake saponins"
1. Using other plant extracts to "impersonate" [the genuine product].
Common materials used in counterfeiting：Yam extract (containing diosgenin, which is identical to the core monomer of Tribulus terrestris), Smilax extract, agave extract, etc.;
Characteristics of counterfeiting：The total saponin content can easily meet the standard (even ≥60%), but it lacks the "characteristic monomer combination" of *Tribulus terrestris* (e.g., containing only diosgenin, but no hecogenin or sarsasapogenin); the source is vaguely described in the test report, only stating "plant extract" instead of "Tribulus terrestris (family Zygophyllaceae)";
2. Using low-activity saponins to "pad the numbers" (i.e., to artificially increase the quantity).
The raw material is genuine *Tribulus terrestris*, but inferior parts (such as branches, leaves, and immature fruits) or substandard processing methods are used to extract low-activity saponins, and then the total saponin content is artificially increased through "dilution + addition of cheap saponins":
Characteristics of counterfeiting：The total saponin content meets the standard (e.g., ≥40%), but the content of the core active monomer (diosgenin) is extremely low (<0.05%); the product has a light color and poor solubility (due to the presence of a large amount of low-activity impurities); the ash content exceeds the standard (>8%), possibly due to the addition of inorganic impurities to increase weight;
Identify key elements：The focus of the inspection is on verifying the content of characteristic monomers such as "diosgenin" in the test reports, and products that only list total saponins without specifying the characteristic monomers will be rejected; ash content and moisture content will also be tested, and exceeding the limits will indicate inferior quality and adulteration.
3. Adding chemically synthesized compounds as a "disguise"
Characteristics of counterfeiting：The test report shows "abnormally high diosgenin content" (e.g., >1.0%, far exceeding the natural extraction limit); the product price is significantly lower than the market average (chemical synthesis costs are much lower than natural extraction); and there may be "unidentified organic solvent residues" (resulting from the synthesis process).
Identify key elements：Be wary of the combination of "ultra-high activity + ultra-low price"; request a "comprehensive solvent residue test." If harmful solvents such as methanol or acetone are detected, or if ethanol residue is abnormally high (>100 ppm), it is highly likely that chemical synthesis and additives were involved.
三、Four key dimensions for identification/authentication.
1. Check raw material traceability.
Source of origin verification：Provide a "species identification report" issued by a professional institution, clearly stating "Tribulus terrestris L." (Tribulus terrestris L.), and avoid vague descriptions;
Origin and harvesting records：The authentic production areas (Henan, Hebei, etc.) certify the harvesting time (autumn-ripening fruits) and raw material processing records (screening, drying methods), ensuring the avoidance of inferior parts or moldy raw materials;
Qualification documents：The supplier's production license (SC) and raw material purchase invoices (proving the compliance of raw material sources) ensure full traceability throughout the entire supply chain.
2. Nuclear component indicators
The ingredient specifications are crucial for distinguishing genuine products from counterfeit ones. Suppliers must provide third-party testing reports from CNAS/CMA accredited laboratories within the past six months, with a focus on verifying the following:
Indicator Type
Core verification indicators
High-quality standard (true saponins)
Warning signs of counterfeiting
Activity indicators
Total saponins, diosgenin
Total saponins ≥40% (UV-VIS method), diosgenin ≥0.2% (HPLC method)
Only total saponins are specified, not individual components; the content of individual components is abnormally high/extremely low; the testing method is unclear.
The manufacturing process directly determines the "activity retention" and "purity" of saponins. High-quality, genuine saponins are produced using processes that meet specific standards, and fraudulent products can be identified by inquiring about these details from the supplier:
Core process requirements：The authentic product is manufactured using a process involving "ethanol reflux extraction (60-70℃) + macroporous resin purification + low-temperature vacuum drying (≤60℃)";
Counterfeiting process signals：The supplier avoided disclosing process details; claimed "high-temperature extraction (>100℃) with no loss of activity"; and the product did not undergo any purification process (only "crushing + simple extraction").
Additional verification：A "process validation report" is required, including data on extraction yield, purification efficiency, etc., to ensure process control.
Procedure: Take 0.1g of the sample, dissolve it in 10mL of ethanol by sonication, and spot the supernatant onto a silica gel G thin-layer chromatography plate. Use a "chloroform-methanol-water (65:35:10)" mixture as the developing solvent. After development, spray with a 10% ethanolic sulfuric acid solution and heat at 105℃ for color development.
Judgment: A genuine product should show 3-5 clear purple spots (corresponding to different saponin monomers); if only one spot appears, or the spots are blurry or smeared, it is likely a counterfeit product.
Method 2: Foam Reaction Test:
Procedure: Take 0.5g of the sample, add 50mL of distilled water, and shake vigorously for 1 minute;
Judgment: Genuine products, due to the presence of natural saponins, will produce persistent foam (lasting for more than 5 minutes without dissipating); if the foam is minimal, dissipates quickly, or if layering or precipitation occurs after shaking, it may indicate low-activity saponins or an adulterated product.
五、Common misconceptions clarified
Misconception 1: "Higher total saponin content means better quality" - Incorrect. High total saponin content may be due to the addition of other plant extracts or chemically synthesized substances; the key is to look at the dual standard of "total saponins + characteristic monomers," not a single indicator.
Misconception 2: "The lower the price, the better the deal" - Incorrect. The raw material and processing costs of genuine Tribulus terrestris extract (total saponins ≥40%, diosgenin ≥0.2%) are clearly defined. If the price is far below the market average (e.g., below 150 yuan/kg), it is likely counterfeit.
Misconception 3: "The whiter the appearance, the better the quality" - Incorrect. Genuine Tribulus terrestris extract is a light brown to yellowish-brown powder; if it is a pure white powder, it may have been bleached with starch, talc powder, or other impurities, or contain chemically synthesized substances.
Misconception 4: "Imported products are definitely better than domestic ones" - Incorrect. The saponin content of Tribulus terrestris from authentic Chinese production areas has reached international standards, and domestic plant extract companies have more mature purification processes, offering far better value for money than imported products; imported products require additional verification of customs duties, customs declarations, and other compliance documents.
Distinguishing between genuine and counterfeit saponins in *Tribulus terrestris* extract cannot be done through a single indicator or visual inspection. The key is to establish a comprehensive evaluation system encompassing "raw material traceability, component testing, process verification, and practical validation."
