Alpha-Bisabolol CAS Numbers and COA Checks Before Buying

A buyer-side guide to stereochemistry, assay, optical rotation, origin claims and supplier qualification

Buyer guide · Cosmetic specialty chemical · Updated October 2026

Quick Answer

One CAS field cannot express both the defined stereochemical form and the broader bisabolol family, so a listing that quotes CAS 515-69-5 is not automatically wrong and one that quotes CAS 23089-26-1 alone does not guarantee a cosmetic grade. Ask each supplier to state the form and the assay method on the quotation, then compare 95%, 98% and 99% offers only after the assay basis is normalised. Rank on identity and documentation first, commercial terms second, and treat any listing that turns a comparison into a ranking with caution.

Quick Answer

For alpha-bisabolol, do not approve a raw material from the name “bisabolol” and an assay number alone. First define which material your formula requires: a specified alpha-bisabolol stereoisomer, a broader bisabolol mixture, or a supplier’s named commercial grade. Then make the CAS number, INCI name, manufacturing route, test method and batch documents agree with that definition. If a supplier sells “natural” or “levomenol,” the certificate should provide evidence that supports the specific claim, such as a stated optical rotation with test conditions and a suitable chromatographic identity or profile. A total GC assay of 98% does not, by itself, establish which stereoisomer makes up that 98% or prove botanical origin.

This distinction matters because listings often compress chemically different ideas into one line: alpha-bisabolol, bisabolol, Dragosantol, “natural bisabolol,” and CAS 515-69-5 may appear as interchangeable labels. They are not enough, on their own, to tell a purchasing team what is in a drum. The useful buyer task is narrower: translate the intended raw-material identity into a written specification, then check the supplier’s COA and supporting documents against it before paying for a sample or approving a production lot.

Why the name and CAS field can mislead

Bisabolol is a family label used across related structures. NIST’s Chemistry WebBook lists alpha-bisabolol under CAS 515-69-5 and shows multiple stereoisomer records; it also lists names such as levomenol and Dragosantol among related names. The USP/Food Chemicals Codex preview for (−)-alpha-bisabolol identifies CAS 23089-26-1 and describes the material as primarily (−)-alpha-bisabolol with minor related beta-bisabolol. Together, these primary references show that broad names and identifiers can describe different levels of specificity.

This does not mean that every listing using CAS 515-69-5 is wrong, or that CAS 23089-26-1 alone guarantees a cosmetic grade. It means one CAS field cannot resolve every identity question. Treat it as one identity field to reconcile, not as a complete specification.

Before requesting quotes, decide whether your formula or regulatory dossier requires (−)-alpha-bisabolol, another defined stereoisomer, a racemic or mixed alpha-bisabolol grade, or a broader INCI “Bisabolol” ingredient. If you do not need a specific stereochemical form, say so explicitly and define the acceptable composition. If you do need it, write the stereochemical descriptor in the specification and ask the supplier to confirm that the quoted product matches it. Do not let a supplier infer the requirement from “natural” or “cosmetic grade.”

What the COA must tell you

A usable certificate of analysis should be lot-specific, dated, attributable to the supplier or testing laboratory, and tied to the exact product name and lot number on the package. A generic “sample COA” may illustrate a test menu, but it is not evidence that the delivered lot passed. Check the document against the packing label, invoice, specification and SDS; names and identifiers should align rather than drift between “bisabolol,” “alpha-bisabolol” and a trade name.

Start with identity. Ask which method supports identity: for example, GC comparison to a reference, a chromatographic profile, or a spectroscopic method appropriate to the material. The method should make sense for the claim. One public research supplier’s sample COA for (−)-alpha-bisabolol reports GC purity, refractive index, specific rotation and 1H-NMR identification; it is a useful example of different fields answering different questions, not a universal mandatory format for every cosmetic batch. A buyer should agree in advance which method and limits are required for their intended use and quality system.

Next, inspect the assay result and its basis. Does “98%” mean GC area percent, a calibrated mass fraction, or another calculation? Is the result reported as alpha-bisabolol, total bisabolols, or a summed chromatographic peak area? A percentage without a named method and definition cannot be compared fairly with another supplier’s percentage. Ask for the chromatogram or a representative profile if stereoisomer distribution or related isomers matter. A high assay can coexist with poor identity information.

For a stereochemically specified or natural-origin grade, look for optical rotation when applicable. The COA should state the measured result, specification range and conditions such as wavelength, temperature, concentration and solvent or neat measurement. The sign alone—positive or negative—is not a complete test result. Optical rotation can support a stereochemical identity claim, but it is not a universal proof of botanical source: mixtures, test conditions and other constituents can affect a reading. If “naturally derived” is a commercial or compliance requirement, request a separate origin declaration and traceability evidence; determine whether the supplier means plant extraction, fermentation, or another route. These routes are not interchangeable claims.

Finally, request the fields your own quality system needs: appearance, water or volatile content where relevant, related substances, residual solvents where relevant to the manufacturing route, storage conditions, retest or shelf-life basis, packaging and transport conditions. A field that is not tested should be marked as not tested or not applicable, rather than filled with an assumed pass. The article cannot set universal acceptance limits: limits should reflect your product specification, applicable rules, risk assessment and intended process.

How to compare 95%, 98% and 99% offers

Do not rank quotations by the largest number in the purity column. First normalize what the assay actually measures. Ask each supplier to quote on the same basis: named ingredient identity, method, assay definition, stereochemical requirement, product form and unit of sale. If one listing reports “99% HPLC” and another reports “98% GC,” the values are not automatically comparable. The analytical methods may separate or quantify different components, and the denominator may not match.

Then compare the cost of the material that meets your specification, not a hypothetical cost per advertised percent. If a supplier’s offer is a mixture that does not satisfy your required stereochemistry, the nominally lower price is not a substitute. If the formula is flexible and the specification permits a broader bisabolol profile, the extra assay point may have little value. Cost-in-use should account for the actual inclusion rate, handling losses, packaging, freight, duties, testing and rejected-lot risk. Ask for a quotation on a sample quantity and on the first realistic production quantity so the comparison reflects the procurement decision you will make.

The available listings are not evidence of a market-wide grade ladder. They are snapshots of supplier offers that can change. For example, one Alibaba offer surfaced as “High Cosmetics Grade Dragosantol Oil Alpha-Bisabolol,” CAS 515-69-5, with a 1 kg minimum and a 12-year Alibaba storefront. The listing is a lead for quote comparison, not technical approval: the broad CAS and title do not establish stereoisomer profile, origin, test method or lot documentation. Treat platform tenure as a business-history signal only. It cannot replace product identity or quality records.

Supplier questions that resolve the uncertainty

Send the same concise questions to every finalist. Ask: What is the exact chemical identity and stereochemical form of the offered lot? Which CAS number and INCI name will appear on the specification, COA and SDS? Is the material extracted, synthesized, or produced by fermentation, and what evidence supports the origin statement? What does the assay percentage measure, which method is used, and can you provide a representative chromatogram? If the grade is specified as (−)-alpha-bisabolol or natural levomenol, what optical-rotation range and conditions are reported? What related isomers or beta-bisabolol are included in the specification? Can you provide a current lot COA, TDS, SDS and origin declaration before the sample order?

Ask operational questions too: Is the quoted unit price per kilogram, per package or per sample? What is the MOQ for the stated grade rather than a different listing variant? Is the sample drawn from current stock or prepared separately? Can the same specification be held for the production lot? What packaging, light protection, storage conditions, lead time and retest period apply? If the supplier says a field is confidential, ask for a signed specification with acceptance limits and a third-party test option. A buyer cannot verify a controlled attribute from a marketing page alone.

The reply itself is informative. A supplier who clarifies the exact grade and sends consistent, lot-relevant documents is easier to qualify than one who responds with a new CAS number, changes the origin claim, or keeps quoting an assay without a method. Keep the answers in the approved specification or purchase order; do not leave critical requirements only in chat messages.

A practical incoming-lot workflow

For the first order, separate sample evaluation from production approval. Review the quote and documents first. Confirm the material identity, grade and intended application, then check the supplier’s sample COA and make sure its lot number corresponds to the sample. Test the sample against the attributes that could change your formula decision: identity, assay using an agreed method, physical appearance, odor if relevant, and stereochemical evidence if required. If the claim is especially important or the supplier’s data are incomplete, have a qualified independent laboratory test a retained sample. A third-party result should be compared with the same agreed method and specification, not with an unrelated generic limit.

Before production release, approve the exact specification. Require the production COA to reference the shipped lot and match the approved name, grade and test methods. On receipt, reconcile the COA, lot number, seals, labels and package integrity. Retain a sample and record storage conditions. If the production result differs from the sample or prior lot, pause use while the supplier investigates.

Ask the supplier to notify you before changes to feedstock source, production route, test laboratory, specification, packaging or manufacturing site. These changes can alter origin claims, impurities or analytical comparability even when the trade name remains unchanged. For recurring purchases, review trends across lots. A stable series of lot results builds more confidence than one impressive sample certificate.

Sourcing candidate for buyer review

One Alibaba listing reviewed for this article is linked below as a starting point for an RFQ, not as a supplier recommendation. It is a cosmetic-grade alpha-bisabolol offer with a displayed 1 kg minimum and a long storefront history; marketplace tenure does not establish assay, stereochemistry or lot consistency.

Common sourcing errors

The first error is treating CAS 515-69-5 and CAS 23089-26-1 as universal synonyms. The authoritative sources above show broader and more specific identity contexts; resolve the form required for your use with the supplier and, where necessary, your regulatory or quality team. The second error is assuming “natural” means (−)-alpha-bisabolol, or that a negative rotation alone proves the botanical source. Ask for composition and origin evidence separately.

The third error is equating purity with suitability. A 99% number without an assay method, peak definition and stereoisomer information may tell you less than a lower, well-characterized grade. The fourth is accepting a generic COA or an undated specification as if it certified your lot. The fifth is confusing an Alibaba badge or years on platform with validated manufacturing capability. Verify the company identity, relevant category experience, facility or quality-system evidence, and document control in proportion to the risk. The sixth is comparing displayed marketplace prices without confirming price units, packaging, grade, shipping terms and order quantity.

A final error is turning a supplier comparison into a ranking. Public listings rarely provide enough comparable, independently verified data to support “best supplier” claims. A more useful buyer guide explains what is known, what is missing and what a buyer should confirm before ordering.

A specification starter you can adapt

A first-pass RFQ can state: “Bisabolol for cosmetic raw-material evaluation. Required identity: [state defined alpha-bisabolol stereochemical form or permitted composition]. INCI: Bisabolol, subject to confirmation for offered grade. CAS: supplier to state the identifier applicable to the exact material and explain any alternate identifier. Assay: report value, method, basis and chromatographic profile. If a stereochemical or natural-origin claim is made, provide optical rotation with test conditions plus separate origin/process documentation. Provide lot-specific COA, current TDS and SDS, packaging details, storage conditions, shelf-life or retest basis, MOQ, sample availability, lead time, and quotation units. No substitution or specification change without written approval.”

This wording is deliberately a starting point, not a finished release specification. Replace bracketed text with your actual formula and compliance requirements. Set numeric limits only after reviewing process needs, applicable rules, method capability and supplier data. If the material is used in a finished cosmetic, assess the finished formula and local regulatory obligations separately; a raw-material COA does not establish finished-product safety, efficacy or regulatory compliance.

Where to start your supplier comparison

For an initial quote, compare offers by identity first, documentation second, and commercial terms third. A listing that names “Dragosantol” and provides a low MOQ may be useful for opening a discussion, but the purchasing decision should remain conditional until the supplier confirms the exact grade and supplies the required batch evidence. Do not order a production quantity solely because the listing title includes “cosmetic grade” or “high purity.”

One current Alibaba listing surfaced under Xi’an Herbking Biotechnology Co., Ltd. as high-cosmetics-grade Dragosantol oil, CAS 515-69-5, with a displayed 1 kg minimum and a 12-year storefront history. These are marketplace-stated commercial details, not independent quality findings, and availability, terms and product page content can change. Before payment, ask the supplier to confirm that the CPS-linked listing still refers to the same bisabolol product, then request the specification and lot documentation described above.

References

1. NIST Chemistry WebBook, SRD
2. Alpha-Bisabolol, CAS 515-69-5 and listed stereoisomers. https://webbook.nist.gov/cgi/cbook.cgi?ID=515-69-5
3. Fiume MM. Bisabolol. International Journal of Toxicology. 2017. doi:10.1177/1091581817716644. https://journals.sagepub.com/doi/10.1177/1091581817716644
4. United States Pharmacopeia, Food Chemicals Codex. (−)-α-Bisabolol, FCC preview. https://doi.usp.org/USPFCC/FCC_F104450_07_01.html
5. Santa Cruz Biotechnology. Sample Certificate of Analysis for (−)-α-Bisabolol. Used as an example of reported analytical fields, not as an industry standard. https://www.scbt.com/p/alpha-bisabolol-23089-26-1