01Product

Dihydromyricetin 98% (HPLC) + optical purity · CAS 27200-12-0

Q: Which grades can you supply?

DHM 98% (HPLC) as the isolated compound — the only grade on which a chiral result is meaningful; 80% and 50% extract concentrates; 20% water-soluble for beverage work; and vine tea leaf polyphenols ≥ 85%, which is the specification written into China's 2026 Announcement No. 5. Tell us the target market in the RFQ, because it usually decides the grade.

Q: Can we sell DHM in the United States?

Ask your regulatory counsel, but know this first: no NDI notification has ever been filed under the name dihydromyricetin or ampelopsin. We parsed FDA's official NDI list (July 2026 version, 2,624 entries) and both names return zero hits. The only related records are NDI 698 and 714, both from one company in 2011 for an Ampelopsis grossedentata extract product, and the nature of FDA's replies is not public. Current US products rest on old-dietary-ingredient or food-ingredient arguments, which is a weaker legal basis than a cleared NDI.

Bulk (2R,3R)-dihydromyricetin from vine tea. The industry spec is achiral “HPLC ≥98%”, which cannot tell a single enantiomer from a racemate. We will report enantiomeric ratio and specific optical rotation on the batch certificate.

At a glance

Bulk dihydromyricetin (DHM) from Zhicheng Bio — supply summary

Zhicheng Bio supplies bulk dihydromyricetin (DHM, ampelopsin; CAS 27200-12-0) at 98% by HPLC from Shanghai, China, and will additionally report optical purity by chiral HPLC or SFC together with specific optical rotation. That second measurement is the point. A conventional “98% by HPLC” figure is produced on an achiral reversed-phase method, which by construction cannot distinguish (2R,3R)-DHM from its enantiomer — so a standard 98% certificate is silent on stereochemistry even though published work links configuration to activity. Zhicheng Bio also supplies the vine tea (Ampelopsis grossedentata) leaf polyphenol grade at ≥85%.

Supplier: Zhicheng Bio, Shanghai, China — B2B raw material only
CAS number: 27200-12-0 · C₁₅H₁₂O₈ · also called ampelopsin
Assay: 98% minimum by achiral HPLC — the industry-standard figure
The specification most suppliers omit: Optical purity by chiral HPLC or SFC, plus specific optical rotation, reported on the batch certificate on request. Achiral RP-HPLC cannot resolve enantiomers, so “98% HPLC” alone does not describe stereochemical quality
Why configuration is at risk: Published work reports that racemisation of DHM accelerates above 80 °C, is promoted by Mg²⁺, Ca²⁺ and Mn²⁺ in process water, and is worsened at pH above 9 — conditions that ordinary hot-water extraction and slow-cooled crystallisation fall inside
Second grade: Vine tea (Ampelopsis grossedentata) leaf polyphenols ≥85%
Solubility constraint: Roughly 0.2 mg/mL in water at 25 °C — a formulation constraint, not a defect
Pharmacopoeial status: No USP, EP, ChP or JP monograph for dihydromyricetin — specification agreed in writing per contract
How to get a price: Email an RFQ with quantity, destination and Incoterm — Zhicheng Bio publishes no list price for this grade

Flavonoid Actives By project

Dihydromyricetin

98% (HPLC) + optical purity · CAS 27200-12-0

CAS 27200-12-0 · C15H12O8

Bulk dihydromyricetin (DHM, ampelopsin) for B2B manufacturing, from vine tea leaf. The whole industry quotes this material as “HPLC ≥ 98%”. That number is achiral — ordinary reverse-phase HPLC cannot separate DHM's enantiomers, so it is silent on whether you are buying (2R,3R)-DHM or a racemate. On request we report enantiomeric ratio by chiral HPLC or SFC and the measured specific optical rotation on the batch certificate. There is no price on this page: this material is quoted per project.

Quote on request RFQ

We do not publish an indicative range for this material: it is quoted per project against your target specification, quantity and analytical package. Send an RFQ and we reply within one business day.

Category: Flavonoid Actives

Availability: Sourced to order — lead time confirmed with your quotation

Packing: 25 kg bags, cartons or drums (standard)

Key supply points

Optical purity reported on request — chiral HPLC (polysaccharide-coated CSP) or SFC, plus measured specific optical rotation
98% by achiral RP-HPLC as the content assay, with myricetin reported as the related substance
Also available as vine tea leaf polyphenols ≥ 85%, matching the specification in China's 2026 Announcement No. 5
Handling limits stated up front: above 80 °C and above pH 9 the configuration is at risk, and Mg²⁺, Ca²⁺ and Mn²⁺ promote racemisation

Documentation with every batch

COA per batchSpec SheetMSDS / SDSExport docs

Third-party lab verification can be arranged pre-shipment on request. Certificates of origin, non-GMO or allergen statements per destination-market requirements.

Request COA & Quote Use the RFQ form

Shipping & Lead Time

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Documentation-first

COA per batch, Spec Sheet and MSDS — reviewed by your QA before anything ships.

Ready-stock depth

Multi-tonne inventory on core SKUs, plus 28 actives held in our US warehouse in Los Angeles for domestic delivery.

Certified supply chain

Sourced from audited, certified manufacturers — ISO, HACCP, Halal & Kosher available.

Flexible export

25 kg bags, cartons or drums; FOB / CIF / DDP by lane, sea or air consolidation.

02What it is

What it is

Identity, source plant, and why two chiral centres change how this material has to be bought.

Dihydromyricetin (CAS 27200-12-0; C₁₅H₁₂O₈; MW 320.25; UNII KD8QND6427), also written DHM, DMY or ampelopsin, is a dihydroflavonol. Its full stereochemical name is the part that matters: (2R,3R)-3,3′,4′,5,5′,7-hexahydroxy-2,3-dihydroflavonol. The molecule has two chiral centres and therefore four theoretically possible stereoisomers, and only the (2R,3R) form occurs in nature.

The commercial source is vine tea — Nekemias grossedentata (Hand.-Mazz.) J. Wen & Z. L. Nie, formerly Ampelopsis grossedentata, in the Vitaceae — grown mainly in Hubei (Laifeng) and Hunan (Zhangjiajie, Yongding) and known locally as 藤茶 or 莓茶. A second botanical source, Hovenia dulcis, the Japanese raisin tree, is what many overseas products actually declare. What makes vine tea unusual as a raw material is how concentrated it is: DHM has been reported “as high as 35%” in A. grossedentata, around 20% of dried leaf across several production areas (21.42%, 20.17% and 16.47% in three surveys), and the 2025 near-complete genome paper puts DHM at about 35% of total flavonoids, accumulating most in young shoots.

Supply behind it is real rather than notional. Laifeng County in Hubei reported 102,000 mu under cultivation in 2025 — up from under 2,000 mu in 2012 — across 8 townships and 110 villages, with 91 producing enterprises and 46 processing plants, and flavonoid extraction yield improved from 60% to 90%; a single local producer reports 150 tonnes per year of flavonoid output. Yongding District in Zhangjiajie reports more than 150,000 mu. For a buyer, this matters in a specific way: raw material at 20–35% active content, in a region with this much processing capacity, means the constraint on quality is not availability. It is process control.

Published purification routes agree on what the difficult part is. Cooling crystallisation — ethanol below 10%, solvent above 85 °C, 0.1–0.3% activated carbon for 1–3 minutes — has been reported to give above 70% yield at above 98% content, with productivity collapsing if the temperature is dropped too fast. An ACS Omega 2020 method introduces Zn²⁺ chelation specifically to stop the molecule oxidising during extraction and purification. Ceramic-membrane filtration followed by vacuum concentration and crystallisation is claimed in CN110201067B. The process registered with China's 2026 new food ingredient approval is leaf, then ethanol extraction, decolourisation, concentration, filtration and drying.

03Optical purity — the specification the industry does not write down

Optical purity — the specification the industry does not write down

This is the genuine differentiator on this material, and it is a measurement, not a marketing line.

The standard commercial specification for DHM is “HPLC ≥ 98%”. That figure is achiral. Ordinary reverse-phase HPLC cannot separate DHM's enantiomers, so a certificate showing 98% by RP-HPLC says nothing about whether the material is (2R,3R)-DHM or a racemate. The literature is explicit that some products sold as (+)-DHM are in fact racemic, because small changes in temperature, pH and metal-ion content during extraction and crystallisation are enough to flip configuration.

The kinetics were mapped systematically in J Food Sci 2024 (PMID 38745380). Temperature above 80 °C markedly accelerates racemisation and 100 °C accelerates it dramatically. Ultrapure water was the most stable medium tested; purified, mineral and tap water were all worse. Fe²⁺ suppresses racemisation, while Mg²⁺, Ca²⁺ and Mn²⁺ significantly promote it. pH below 5.0 protects the configuration and pH above 9.0 destroys it. The same paper identified a further pair of DMY isomers for the first time.

There is a reason this goes beyond purity theatre. Semi-preparative supercritical fluid chromatography has been used to separate DHM enantiomers and to compare their anti-inflammatory activity in vitro, and the enantiomers were not equivalent (J Chromatogr A 2019). If measured activity differs by configuration, then configuration is a quality attribute — and at present it is neither specified nor priced anywhere in the trade.

So this is what we offer, and it is the reason to buy this material from us rather than from a listing. On request we will report, on the batch certificate: enantiomeric ratio / optical purity by chiral HPLC on a polysaccharide-coated chiral stationary phase with hexane–ethanol, or by RP-HPLC with a β-cyclodextrin mobile-phase additive, or by SFC; together with the measured specific optical rotation, stating solvent and concentration. We deliberately do not publish a target rotation value, because we could not verify a reference figure for (2R,3R)-DHM in our source review — the measured value is reported and the acceptance range is agreed with your QA. That is a real specification with a real method behind it, and it is the one attribute a standard 98% certificate cannot give you.

04Identity & properties

Identity & properties

Compound identifiers and physical properties for this material. The binding version is always the Specification Sheet and batch COA issued with your quotation.

Chemical name	(2R,3R)-3,3′,4′,5,5′,7-Hexahydroxy-2,3-dihydroflavonol
CAS No.	27200-12-0
Molecular formula	C₁₅H₁₂O₈
Molecular weight	320.25
UNII	KD8QND6427
Synonyms	Dihydromyricetin · DHM · DMY · Ampelopsin · Ampeloptin · 二氢杨梅素 / 蛇葡萄素 (zh)
Stereochemistry	Two chiral centres; four theoretically possible stereoisomers. Only (2R,3R) occurs in nature. Achiral RP-HPLC cannot distinguish the enantiomers.
Botanical source	Nekemias grossedentata (Hand.-Mazz.) J. Wen & Z. L. Nie (formerly Ampelopsis grossedentata), Vitaceae — vine tea leaf. Hovenia dulcis is a second published source.
Appearance	White to off-white crystalline powder
Solubility	Approximately 0.2 mg/mL in water at 25 °C and 0.9 mg/mL at 37 °C; dissolves in hot water and in ethanol. Measured logP was not established in the literature we reviewed — treat any logP figure you are quoted with caution.
Pharmacopoeial reference	No monograph located for the isolated compound. Vine tea has provincial and group standards (Hubei TCM material standard 鄂YC-20220001; T/ZMX 001—2025; T/HNTI 074—2025; DB43/T 2388—2022) but our review found no GB or industry standard for DHM raw material.

05Specifications

Specifications

Typical parameters below — the binding version is the Specification Sheet and batch COA we send with your quotation.

Parameter	Specification	Test method
Appearance	White to off-white crystalline powder	Visual
Identification	Retention time and UV spectrum correspond to the reference standard	HPLC-DAD
Assay (dihydromyricetin)	≥ 98.0% on the dried basis, achiral	RP-HPLC (UV/DAD)
Optical purity / enantiomeric ratio — (2R,3R) vs (2S,3S)	Reported on request; acceptance range agreed with your QA	Chiral HPLC on polysaccharide-coated CSP (hexane–ethanol), RP-HPLC with β-cyclodextrin additive, or SFC
Specific optical rotation	Measured value reported, with solvent and concentration stated. We publish no target range because we could not verify a reference figure for (2R,3R)-DHM	Polarimetry
Myricetin (related substance)	Reported	RP-HPLC (UV/DAD)
Total polyphenols — ≥85% grade only	≥ 85 g/100 g	Spectrophotometric / as agreed, aligned with China's 2026 Announcement No. 5
Loss on drying	—	Gravimetric, 105 °C
Ash / residue on ignition	—	Pharmacopoeial method
Heavy metals — Pb, As, Cd, Hg	—	ICP-MS
Residual solvents — ethanol	Reported, ICH Q3C classes observed	GC headspace
Solvate / crystal form	Reported where controlled. DHM readily forms solvates — cocrystal solvates with methanol, ethanol, acetone and acetonitrile are documented	XRPD / TGA as agreed
Microbiological — TAMC, TYMC, E. coli, Salmonella	—	Pharmacopoeial methods
Particle size	As agreed; mesh specification available	Sieve analysis
Water solubility	≈ 0.2 mg/mL at 25 °C; ≈ 0.9 mg/mL at 37 °C (literature)	Reported for information; method-dependent

A dash means we have no fixed limit to publish for that parameter: it is reported on the batch COA and the limit is agreed with your QA. We would rather leave it blank than invent a number.

Grades we can source

Grade	Description
DHM 98% (HPLC)	Isolated compound, white to off-white crystalline powder. The grade to specify when optical purity matters — and the only grade on which a chiral result is meaningful.
DHM 80% / 50%	Extract concentrates. Sourced to specification; the balance is the native vine tea flavonoid and polyphenol matrix, reported rather than assumed.
DHM 20%, water-soluble	For beverage and solid-drink applications where solubility, not assay, is the limiting factor.
Vine tea leaf polyphenols ≥ 85%	Specification aligned with China's 2026 Announcement No. 5: principal constituents DHM and other polyphenols at ≥ 85%, with a recommended intake of no more than 470 mg/day of total polyphenols. This is the grade to use if your target market is China.

06Analytical & QC notes

Analytical & QC notes

Why a standard release method is not sufficient for this material, and what to add.

DHM is the clearest case we handle of a material where the industry-standard method measures the wrong thing well. Content by achiral RP-HPLC is necessary and easy; configuration is the attribute that published work links to activity, and it needs a different column or a different technique altogether.

Achiral reverse-phase HPLC cannot resolve DHM's enantiomers. An assay of 98% by RP-HPLC establishes content, not configuration. If a supplier's answer to a question about optical purity is to resend the HPLC certificate, the question has not been answered.

Three published chiral options exist, and we can work to any of them: RP-HPLC with β-cyclodextrin as a mobile-phase additive on C18; direct chiral HPLC on a polysaccharide-coated chiral stationary phase with hexane–ethanol; and semi-preparative supercritical fluid chromatography, which is what was used to separate the enantiomers and compare their activity.

A stability-indicating assay can be built from the published base rather than from scratch: the identification of thermal degradation products in neutral aqueous solution at 100 °C, combined with the racemisation kinetics from J Food Sci 2024, covers both the chemical and the stereochemical degradation pathways.

Myricetin is the obvious related substance, being the oxidation partner of DHM, and it should be reported rather than lumped into a total. Thermal degradation in neutral water at 100 °C is not a single clean reaction either: isomerisation, oxidation, hydroxylation, dimerisation and ring opening have all been reported to occur together.

Reference standards: Sigma-Aldrich SML0295 and SML4070 are supplied at ≥98% by HPLC. Whether NIFDC provides an official Chinese reference standard for DHM was not something we could verify, and no GB or industry standard for DHM raw material was found — vine tea has provincial and group standards, but the isolated compound does not.

Solvates and cocrystals are a real scale-up issue, not a curiosity: DHM has been shown to form cocrystal solvates with ciprofloxacin hydrochloride in methanol, ethanol, acetone and acetonitrile. Residual-solvent control and crystal-form control belong in the specification if your process is sensitive to either.

For pharmacokinetic work, published plasma methods use LC-MS/MS, and metabolism proceeds through reduction, dehydroxylation, methylation, glucuronidation and sulfation — so parent compound alone will understate exposure here too.

07Formulation & handling notes

Formulation & handling notes

The practical points our technical team raises with buyers of this material — the things that decide whether a batch behaves in your process.

Keep process temperatures below 80 °C wherever the material is in solution. Above that, racemisation accelerates markedly; at 100 °C it is rapid, and thermal degradation in neutral water proceeds by isomerisation, oxidation, hydroxylation, dimerisation and ring opening at the same time.

Hold aqueous systems weakly acidic. pH below 5 protects the configuration; pH above 9 destroys it. DHM has been reported stable only at low temperature and weakly acidic pH, around 6.0.

Watch the mineral profile of your water and your excipients, not just your actives. Mg²⁺, Ca²⁺ and Mn²⁺ promote racemisation; Fe²⁺ suppresses it; ultrapure water was the most stable medium tested. Hard water, mineral premixes and calcium-rich matrices are therefore a risk to configuration, not only to appearance.

Slow degradation is real at moderate temperatures. A 60 µg/mL solution lost about 40% of its content over 16 days at 60 °C, with the rate depending on pH and on Fe³⁺, Al³⁺ and Cu²⁺. Plan hold times for intermediates accordingly.

Solubility is the other hard constraint: roughly 0.2 mg/mL in water at 25 °C. Published solubilisation approaches include β-cyclodextrin (about 14×), HP-β-cyclodextrin (10–30×), PVP K30 solid dispersions, self-emulsifying systems (about 130×, and notably only 0.4% degradation over 30 days versus 55.8% for an ethanol solution) and an O/W microemulsion reported at up to 875× (0.2 to 175.2 mg/mL). None of these is on the shelf as a commercial DHM product, which is where a formulator still has room.

Oral exposure is low: rat absolute oral bioavailability has been reported at 4.02%. The chain is dissolution-limited absorption, poor gastrointestinal stability, P-glycoprotein efflux (reversible in Caco-2 by verapamil and ciclosporin A) and extensive phase II glucuronidation and sulfation. If your product concept depends on systemic exposure, that chain is the design problem.

A self-emulsifying route is worth considering for stability as much as for solubility: the same system reported 130× solubility and only 0.4% degradation over 30 days. Stability and exposure are not independent problems for this molecule.

If you need a defined optical purity, say so in the RFQ. It changes the analytical package, the acceptance criteria and possibly the process, and it is the one attribute a standard 98% COA cannot tell you.

For China-market products, specify the ≥85% total-polyphenol grade and design to the 470 mg/day total-polyphenol ceiling in Announcement No. 5, and note the excluded populations. For other markets, confirm status before you commit to artwork.

08Applications

Applications

B2B manufacturing use only — no finished-product or health claims.

Beverages and solid drinks, subject to the approvals in your market

Capsules, tablets and powder blends (B2B manufacture)

Formulation, solubilisation and stabilisation R&D

Analytical reference and chiral method development

Food-preservation and antimicrobial research

Contract manufacturing and private label

09Regulatory status by market

Regulatory status by market

Status of the raw material, stated as conservatively as our sources allow. This is supply-chain information, not regulatory advice — confirm the position for your finished product and destination market with your own regulatory counsel.

Market	Status	Basis
China — food	Approved in two steps. Vine tea leaf (显齿蛇葡萄叶) has been a new food raw material since 2013, but with the consumption method limited to infusion. Vine tea leaf polyphenols (显齿蛇葡萄叶多酚) were approved in 2026: DHM and other polyphenols at ≥ 85%, recommended intake ≤ 470 mg/day, and not suitable for infants and young children, pregnant women or lactating women.	NHC Announcement 2013 No. 16 (24 December 2013) and Announcement 2026 No. 5 (published 27 May 2026; some secondary sources give 13 May — check the NHC original). The registered process is leaf, ethanol extraction, decolourisation, concentration, filtration, drying. The list of permitted food categories circulating in secondary interpretations is not consistent between versions, so verify against the announcement annex before you finalise labelling.
China — health food	Not in the health food raw material catalogue, so a health food product must go through registration rather than filing. Not in the medicinal-and-edible substances catalogue either. “Hangover relief” is not a legally permitted health function claim in China.	Absence from both catalogues as of our review in July 2026; permitted health functions are set by the 2023 edition of the official catalogue of health functions for health food.
China — traditional Chinese medicine route	Vine tea has a provincial TCM materials standard and a reimbursement route in Hubei.	Hubei provincial standard for TCM materials 鄂YC-20220001 (2022); Hubei authentic-material list (2025); Hubei 2025 basic medical insurance list of TCM decoction pieces, one of 159 items, Class A.
United States	No new dietary ingredient notification has ever been submitted under the name dihydromyricetin or ampelopsin.	We parsed FDA's official List of NDINs 1995 to the Present (July 2026 version, 2,624 entries): zero hits for either name. The only related records are NDI 698 and NDI 714, both from BF Suma Pharmaceuticals Inc. for an Ampelopsis grossedentata extract product, submitted 14 February 2011 and 19 June 2011; the nature of FDA's replies is not public and we have not verified it. Products on the US market therefore rely on old-dietary-ingredient or food-ingredient arguments rather than on a DHM NDI. A warning letter is also on record against a marketer in this category (Synaptent, LLC, ref. 610683, 9 November 2021); the letter is no longer retrievable at its original address and we make no representation about its contents.
European Union	Unconfirmed. We do not claim Novel Food status for DHM or for vine tea.	We could not verify an entry for dihydromyricetin, ampelopsin or Nekemias / Ampelopsis grossedentata in the EU Novel Food Status Catalogue. Under Regulation (EU) 2015/2283, a plant extract without significant EU consumption history before 15 May 1997 would generally require authorisation.
Japan · Canada (NHP)	Unconfirmed — no determination located in our review.	Confirm directly before planning a launch in either market.
Safety-data context	LiverTox records typical US supplement doses of 300–1,000 mg/day, no reported cases of clinically apparent liver injury, and a hepatotoxicity likelihood score of E (unlikely).	NCBI Bookshelf NBK594407. Note what is missing: our review found no publicly available 90-day subchronic study or standard genotoxicity battery for DHM, and we will not quote an LD50 or a NOAEL because we could not verify one. China's 2026 approval reflects the same gap by excluding infants, pregnant and lactating women on the basis of insufficient safety data.

10Selected research

Selected research

Peer-reviewed literature on the compound, linked so you can read the primary source. Cited for scientific context only — not claims about this material or any finished product.

Human evidence for the isolated compound is thin, and you should hear that from your supplier rather than discover it later. A PubMed-filtered search finds two published randomised controlled trials, both from Chinese groups. The first (Pharmacol Res 2015) studied 60 patients with non-alcoholic fatty liver disease taking two 150 mg capsules twice daily — about 600 mg/day, not the 300 mg/day that many secondary sources quote — for three months; that paper attracted four published Comments, one of which points out a high degree of similarity in design and data between it and the same group's resveratrol trial in the same indication. The second (Eur J Clin Nutr 2019) randomised 80 patients with type 2 diabetes, 70 completing, to 10 g/day of vine tea containing 970 mg of DHM against the same vine tea with the DHM removed — an unusually well-designed control — for one month.

A 2026 systematic review from USC covering 22 studies concludes that clinical evidence is limited to two small trials using Hovenia dulcis extract and that no trial has directly evaluated DHM as a single compound, with ethanol-metabolism and neurobehavioural results inconsistent. The first-in-human Phase 1 pharmacokinetic study (NCT05623501) was registered in 2022 and was still listed as not yet recruiting at its most recent update, four years on.

One thing we will not do is repeat a number we cannot find. A claim circulating widely online — that a 2024 paper in Foods showed roughly a 70% reduction in hangover severity — does not correspond to anything we can locate in PubMed, and the 2026 systematic review states plainly that no trial of the isolated compound exists. We do not cite it, and we would advise you not to repeat it in your own materials.

These references are listed for scientific context only. They describe published research on the compound; they are not claims about this raw material and not claims about any finished product. Zhicheng Bio makes no medical, health or performance claims.

Chirality and configuration protection: temperature above 80 °C accelerates racemisation (100 °C markedly); ultrapure water is the most stable medium; Fe²⁺ suppresses racemisation while Mg²⁺, Ca²⁺ and Mn²⁺ promote it; pH below 5.0 protects and above 9.0 destroys configuration. A further pair of DMY isomers was identified. Li S, Sha X, Sun S, Zhang X, Guo D, Huang S. Study on the stability of molecular chirality and the configuration protection of dihydromyricetin in vine tea. J Food Sci 2024;89(6):3569-3576. PMID 38745380 DOI 10.1111/1750-3841.17105
Semi-preparative separation of DHM enantiomers by supercritical fluid chromatography, with a comparison of anti-inflammatory activity between the enantiomers — the direct evidence that configuration belongs in the specification. Semi-preparative separation of dihydromyricetin enantiomers by supercritical fluid chromatography and determination of anti-inflammatory activities. J Chromatogr A 2019. Source
Extraction and purification with Zn²⁺ chelation to prevent oxidation during processing; DMY reported “as high as 35%” in A. grossedentata. Hu H, Luo F, Wang M, Fu Z, Shu X. New method for extracting and purifying dihydromyricetin from Ampelopsis grossedentata. ACS Omega 2020;5(23):13955-13962. PMID 32566862 DOI 10.1021/acsomega.0c01222
Comprehensive review covering solubility (0.2 mg/mL at 25 °C, 0.9 mg/mL at 37 °C), reported rat absolute oral bioavailability of 4.02%, and the signalling pathways studied. Dihydromyricetin: an emerging compound with comprehensive effects on multiple systems. Front Pharmacol 2024;15:1488003. DOI 10.3389/fphar.2024.1488003
Review of delivery strategies for DHM, with measured solubility and bioavailability multiples for cyclodextrin complexes, solid dispersions, self-emulsifying systems, microemulsions, micelles and liposomes. Zhang R, et al. Strategic developments in the drug delivery of natural product dihydromyricetin. Drug Deliv 2022;29(1):3052-3070. DOI 10.1080/10717544.2022.2125601
Review of identification and quantification methods, chemical stability, metabolism and approaches to improving bioavailability. Zhang J, et al. Dihydromyricetin: a review. Trends Food Sci Technol 2019;91:586-597. PMID 32288229 DOI 10.1016/j.tifs.2019.07.038
Tissue distribution, excretion and metabolic profile after oral administration in rats — reduction, dehydroxylation, methylation, glucuronidation and sulfation. Tissue distribution, excretion, and metabolic profile of dihydromyricetin after oral administration in rats. J Agric Food Chem 2017. DOI 10.1021/acs.jafc.7b01155
In vitro gastrointestinal stability of dihydromyricetin, myricetin and myricitrin. Gastrointestinal stability of dihydromyricetin, myricetin, and myricitrin: an in vitro investigation. PMID 28114854
Thermal degradation of (2R,3R)-DHM in neutral aqueous solution at 100 °C: isomerisation, oxidation, hydroxylation, dimerisation and ring opening identified together. Thermal degradation of (2R,3R)-dihydromyricetin in neutral aqueous solution at 100 °C. Food Chem 2024. Source
Salt cocrystallisation to improve solubility and bioavailability; cocrystal solvates form in methanol, ethanol, acetone and acetonitrile, and the reported 8× relative bioavailability comes with reduced stability under humidity. Li J, Chen X, Liu Y, Jiang C. Salt cocrystallization — a method to improve solubility and bioavailability of dihydromyricetin. Pharmaceutics 2025;17(9):1209. PMID 41012544 DOI 10.3390/pharmaceutics17091209
Randomised controlled trial in non-alcoholic fatty liver disease, n = 60, two 150 mg capsules twice daily (about 600 mg/day) for three months. Read together with the Comment below. Chen S, et al. Pharmacol Res 2015;99:74-81. PMID 26032587 DOI 10.1016/j.phrs.2015.05.009
Published Comment questioning the similarity in design and data between the DHM trial above and the same group's resveratrol trial in the same indication. Similarity between studies of dihydromyricetin and resveratrol for NAFLD. Pharmacol Res 2015;100:335. PMID 26318761 DOI 10.1016/j.phrs.2015.07.034
Randomised controlled trial in type 2 diabetes, n = 80 (70 completed): vine tea 10 g/day containing 970 mg DMY versus the same vine tea with DMY removed, one month. Ran L, et al. Eur J Clin Nutr 2019;73(5):776-782. PMID 30089792 DOI 10.1038/s41430-018-0282-z
Systematic review of 22 studies: clinical evidence is limited to two small trials using Hovenia dulcis extract, no trial has directly evaluated DHM as a single compound, and ethanol-metabolism and neurobehavioural results are inconsistent. Skinner SG, Matcha S, Davies DL. Therapeutic effects of dihydromyricetin on wholly alcohol-attributed conditions: a systematic review. Nutrients 2026;18(14):2221. PMID 42514290 DOI 10.3390/nu18142221
Near-complete genome assembly of A. grossedentata; DHM about 35% of total flavonoids, accumulating most in young shoots; ten key flavonoid pathway genes identified. Yao Z, Feng Z, Wu F, et al. Front Plant Sci 2025;16:1580779. DOI 10.3389/fpls.2025.1580779
Safety-data context: typical US supplement doses of 300–1,000 mg/day, no reported cases of clinically apparent liver injury, hepatotoxicity likelihood score E. LiverTox: Dihydromyricetin. NCBI Bookshelf NBK594407. Source

11Documentation, packing & storage

Documentation, packing & storage

Documents per batch	COA (assay, myricetin, loss on drying, heavy metals, residual solvents, microbiological), Specification Sheet, MSDS / SDS
Chiral package on request	Enantiomeric ratio by chiral HPLC or SFC, measured specific optical rotation with solvent and concentration stated, and the chromatograms behind both
Analytical detail on request	Method parameters, chromatograms and botanical source declaration; third-party laboratory verification can be arranged pre-shipment
Sample / trial unit	1 kg bag; 25 kg drum for commercial batches, per the trade convention for this material
Storage	Sealed in the original packaging, cool and dry. Keep away from heat: the configuration is at risk above 80 °C in solution
Lead time	Sourced to order — confirmed with your quotation
Shipping	Sea or air consolidation out of Shanghai · FOB / CIF / DDP by lane
Claims	Raw material for B2B manufacturing. We make no medical, health or performance claims — including no hangover, liver or metabolic claims — and we do not supply marketing copy for finished products.

12Procurement FAQ

Procurement FAQ

01Why do you report optical purity when everyone else just writes “HPLC ≥98%”?

Because “HPLC ≥98%” is achiral and therefore cannot distinguish (2R,3R)-DHM from a racemate, and the literature is explicit that some material sold as (+)-DHM is in fact racemic. Published work has also separated the enantiomers by supercritical fluid chromatography and found their measured anti-inflammatory activity in vitro differed. If activity depends on configuration, configuration is a quality attribute. On request we report enantiomeric ratio by chiral HPLC or SFC and the measured specific optical rotation on the batch certificate — with the chromatograms.

02What is the target specific optical rotation?

We do not publish one, on purpose. Our source review could not verify a reference rotation figure for (2R,3R)-DHM, and inventing an acceptance range would defeat the point of measuring it. What we do is report the measured value, state the solvent and concentration, and agree the acceptance range with your QA. If someone quotes you a tidy target value, ask them for the reference.

03Which grades can you supply?

DHM 98% (HPLC) as the isolated compound — the only grade on which a chiral result is meaningful; 80% and 50% extract concentrates; 20% water-soluble for beverage work; and vine tea leaf polyphenols ≥ 85%, which is the specification written into China's 2026 Announcement No. 5. Tell us the target market in the RFQ, because it usually decides the grade.

04How should we handle DHM in processing?

Four rules, all from published work. Keep solution temperatures below 80 °C — above that racemisation accelerates markedly and at 100 °C several degradation pathways run at once. Keep aqueous systems weakly acidic: pH below 5 protects the configuration, pH above 9 destroys it. Watch your mineral profile: Mg²⁺, Ca²⁺ and Mn²⁺ promote racemisation, Fe²⁺ suppresses it, and ultrapure water was the most stable medium tested. And limit hold times on warm intermediates: a 60 µg/mL solution lost about 40% over 16 days at 60 °C.

05Can we sell DHM in the United States?

Ask your regulatory counsel, but know this first: no NDI notification has ever been filed under the name dihydromyricetin or ampelopsin. We parsed FDA's official NDI list (July 2026 version, 2,624 entries) and both names return zero hits. The only related records are NDI 698 and 714, both from one company in 2011 for an Ampelopsis grossedentata extract product, and the nature of FDA's replies is not public. Current US products rest on old-dietary-ingredient or food-ingredient arguments, which is a weaker legal basis than a cleared NDI.

06What is the position in China?

Better than it was, and specific. Vine tea leaf has been a new food raw material since Announcement 2013 No. 16, but the permitted consumption method was infusion only — which is why the category sat in tea bags for thirteen years. Announcement 2026 No. 5 approved vine tea leaf polyphenols: principal constituents DHM and other polyphenols at ≥ 85%, recommended intake ≤ 470 mg/day of total polyphenols, and not suitable for infants and young children, pregnant women or lactating women. DHM is not in the health food raw material catalogue, so a health food product needs registration; and “hangover relief” is not a legally permitted health function claim. Verify the permitted food categories against the announcement annex — the lists circulating in secondary interpretations disagree with each other.

07Can you provide toxicology data?

Not beyond what is published, and we will not quote what we cannot source. Our review found no publicly available 90-day subchronic study and no standard genotoxicity battery for DHM, and no verifiable LD50 or NOAEL — so we quote none. What does exist: LiverTox (NBK594407) records typical US supplement doses of 300–1,000 mg/day, no reported cases of clinically apparent liver injury, and a hepatotoxicity likelihood score of E, unlikely. China's 2026 approval acknowledges the same gap by excluding infants, pregnant and lactating women on the grounds of insufficient safety data. If you need a GLP package for an NDI or Novel Food dossier, treat it as a study to commission.

08What about the hangover claims we see everywhere?

We do not make them and we would rather you did not repeat them. DHM is the most common ingredient in the US hangover-product market, but the 2026 systematic review is explicit that no clinical trial has evaluated the isolated compound. The widely quoted “2024 Foods RCT showing about 70% lower hangover severity” does not correspond to anything we can find in PubMed, and we will not cite it. In China, “hangover relief” is not a legally permitted health function claim. We sell a characterised raw material with a real chiral specification; the claims are your regulatory risk, and thin ones are not worth taking.

09What is the MOQ and how is it priced?

Project-based, and there is no indicative range on this page because we do not yet have honest costing to publish for this material. Send the grade, target specification (including whether you need the chiral package), quantity and destination in an RFQ and you will have a firm quotation, lead time and document list back within one business day. 1 kg for trials, 25 kg drums for commercial batches.

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