Cichoric Acid

Cichoric Acid at a Glance

Cichoric acid — more often spelled chicoric acid — is a dicaffeoyltartaric acid: two units of caffeic acid esterified to a central tartaric-acid backbone. It is the signature caffeic-acid derivative of purple coneflower (Echinacea purpurea) and takes its name from chicory (Cichorium intybus), where it was first identified ^{1Reference 1Lee J · 2013Chicoric acid: chemistry, distribution, and productionView study →}.

In practice its most concrete role is as the routine quality marker for Echinacea: because it is the predominant phenolic in E. purpurea, its measured content is used to standardise and grade commercial preparations ^{3,6Reference 3Pellati F et al. · 2005Variability in the composition of anti-oxidant compounds in Echinacea species by HPLCView study →Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}. The molecule itself is a genuine antioxidant and, in the laboratory, a well-characterised reversible inhibitor of HIV-1 integrase — the finding it is best known for in pharmacology ^{2,4Reference 2Robinson WE Jr · 1998In vitroL-chicoric acid, an inhibitor of human immunodeficiency virus type 1 (HIV-1) integrase, improves on the in vitro anti-HIV-1 effect of Zidovudine plus a protease inhibitor (AG1350)View study →Reference 4Lin Z et al. · 1999Chicoric acid analogues as HIV-1 integrase inhibitorsView study →}.

The honest posture here: cichoric acid’s antiviral, anti-inflammatory and metabolic activities are in-vitro and cell-based, on the isolated molecule or on whole Echinacea extract. There are no human efficacy trials of isolated cichoric acid, and — importantly — it is poorly absorbed and enzymatically unstable, two facts that temper any leap from a culture dish to a clinical claim ^{5,6Reference 5Stevenson LM et al. · 2005Modulation of macrophage immune responses by EchinaceaView study →Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}.

The Echinacea Quality Marker — and Why It Degrades

Cichoric acid is the compound most Echinacea products are standardised to. As the dominant caffeic-acid derivative in E. purpurea, its concentration is the usual yardstick for whether a batch of coneflower is potent, correctly identified, or has been degraded in processing ^{3,6Reference 3Pellati F et al. · 2005Variability in the composition of anti-oxidant compounds in Echinacea species by HPLCView study →Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}.

That last point is the molecule’s defining industrial quirk: cichoric acid is enzymatically unstable in Echinacea preparations. Nüsslein and colleagues showed that E. purpurea’s own polyphenol oxidases (PPO) — not peroxidases — oxidatively degrade cichoric acid and the other caffeic-acid derivatives once plant tissue is cut and hydrated; a separate esterase additionally hydrolyses the ester bonds between the tartaric acid and its two caffeic-acid arms ^{6Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}. Left unchecked, a “high-cichoric-acid” harvest can lose much of that marker before it reaches a bottle.

The fix is a processing story, not a pharmacology one: degradation is suppressed by adding antioxidants or working under nitrogen, and the authors held cichoric acid steady for four weeks by extracting into 40% ethanol with 50 mM ascorbic acid ^{6Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}. This is why fresh-plant tinctures made with prompt alcohol extraction tend to preserve cichoric acid better than slowly dried, aqueous material — and why the marker is as much a test of handling as of plant chemistry.

HIV-1 Integrase Inhibition

The single most-studied property of the isolated molecule is that L-chicoric acid inhibits HIV-1 integrase — the viral enzyme that splices HIV DNA into the host genome. It is a reversible, largely non-competitive inhibitor active at sub-micromolar to low-micromolar concentrations, and in infected-cell assays chicoric acid and its dicaffeoyltartaric analogues blocked HIV-1 replication with EC50 values in the low-micromolar range ^{4Reference 4Lin Z et al. · 1999Chicoric acid analogues as HIV-1 integrase inhibitorsView study →}.

Two lines of evidence make this more than a screening hit. First, resistance mapped to the integrase itself: a single amino-acid change (position 140) in integrase confers resistance, and later work showed cross-resistance between chicoric acid and the diketo-acid integrase inhibitors — placing chicoric acid on the same target as a clinically validated drug class ^{8Reference 8Lee DJ · 2004Human immunodeficiency virus type 1 (HIV-1) integrase: resistance to diketo acid integrase inhibitors impairs HIV-1 replication and integration and confers cross-resistance to L-chicoric acidView study →}. Second, adding L-chicoric acid to zidovudine plus a protease inhibitor improved anti-HIV activity beyond any of the drugs alone, and combinations of reverse-transcriptase, protease and integrase inhibitors including chicoric acid were synergistic in vitro against both drug-sensitive and drug-resistant clones ^{2,9Reference 2Robinson WE Jr · 1998In vitroL-chicoric acid, an inhibitor of human immunodeficiency virus type 1 (HIV-1) integrase, improves on the in vitro anti-HIV-1 effect of Zidovudine plus a protease inhibitor (AG1350)View study →Reference 9Beale KK · 2000In vitroCombinations of reverse transcriptase, protease, and integrase inhibitors can be synergistic in vitro against drug-sensitive and RT inhibitor-resistant molecular clones of HIV-1View study →}.

The caveat is decisive, and it is why chicoric acid never became a drug: in cells, much of the anti-integrase and antiviral effect is thought to reflect interference at the cell surface / viral entry step, its two catechol groups make it prone to non-specific redox and metal chelation, and — as with all its activities — the molecule is poorly absorbed orally ^{4,8Reference 4Lin Z et al. · 1999Chicoric acid analogues as HIV-1 integrase inhibitorsView study →Reference 8Lee DJ · 2004Human immunodeficiency virus type 1 (HIV-1) integrase: resistance to diketo acid integrase inhibitors impairs HIV-1 replication and integration and confers cross-resistance to L-chicoric acidView study →}. The HIV work is a real, well-documented mechanism, not a treatment.

What It's Used For

Cichoric acid’s pharmacology is a set of isolated-molecule and cell-based signals — antiviral, anti-inflammatory/immune, antioxidant, and metabolic — with no human efficacy data. Read every row against two headline facts: poor oral absorption and enzymatic instability.

Evidence by IndicationStrength of support · Beta

Support is an experimental score — weighted by study type (human > animal > in vitro) and volume. A beta, not a validated metric. Every row here is preclinical (isolate or whole-extract), so scores are capped low; read the per-row basis.

01Antiviral (HIV-1 Integrase)Shaky42%Reversible integrase inhibition, mapped resistance, in-vitro antiretroviral synergy — no human data ^{2,4,8,9Reference 2Robinson WE Jr · 1998In vitroL-chicoric acid, an inhibitor of human immunodeficiency virus type 1 (HIV-1) integrase, improves on the in vitro anti-HIV-1 effect of Zidovudine plus a protease inhibitor (AG1350)View study →Reference 4Lin Z et al. · 1999Chicoric acid analogues as HIV-1 integrase inhibitorsView study →Reference 8Lee DJ · 2004Human immunodeficiency virus type 1 (HIV-1) integrase: resistance to diketo acid integrase inhibitors impairs HIV-1 replication and integration and confers cross-resistance to L-chicoric acidView study →Reference 9Beale KK · 2000In vitroCombinations of reverse transcriptase, protease, and integrase inhibitors can be synergistic in vitro against drug-sensitive and RT inhibitor-resistant molecular clones of HIV-1View study →}

02Antioxidant (Phenolic)Shaky34%In-vitro ROS scavenging + AMPK activation in myotubes; Echinacea DPPH activity ^{3,7Reference 3Pellati F et al. · 2005Variability in the composition of anti-oxidant compounds in Echinacea species by HPLCView study →Reference 7Schlernitzauer A et al. · 2013Chicoric acid is an antioxidant molecule that stimulates AMP kinase pathway in L6 myotubes and extends lifespan in Caenorhabditis elegansView study →}

03Anti-Inflammatory / ImmuneShaky32%↓ LPS-stimulated TNF-α in macrophages, but poorly absorbed ^{5Reference 5Stevenson LM et al. · 2005Modulation of macrophage immune responses by EchinaceaView study →}

04Metabolic (AMPK / PTP1B)Shaky22%Myotube + C. elegans data only; isolate, preclinical ^{7Reference 7Schlernitzauer A et al. · 2013Chicoric acid is an antioxidant molecule that stimulates AMP kinase pathway in L6 myotubes and extends lifespan in Caenorhabditis elegansView study →}

Mechanisms

The load-bearing tension: cichoric acid has a genuinely mapped molecular target (integrase) and clear di-catechol chemistry, but is undermined for human use by poor absorption and by being a substrate for its own plant’s degrading enzymes.

Pharmacokinetics

The decisive pharmacokinetic fact is poor oral bioavailability. In a controlled comparison, cichoric acid did not cross the intestinal barrier and was undetectable in blood plasma, leading the authors to judge it “unlikely to be relevant” to Echinacea’s in-vivo immune activity ^{5Reference 5Stevenson LM et al. · 2005Modulation of macrophage immune responses by EchinaceaView study →} — a rare, explicit statement that low absorption breaks the chain from in-vitro potency to systemic effect. Mechanistically this is expected: a large, highly polar, doubly-esterified di-catechol acid is a poor candidate for passive absorption, and its ester bonds are labile to gut and plant esterases, which would liberate caffeic acid and tartaric acid ^{6Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}. No validated human half-life, active-metabolite profile or absolute bioavailability figure is established for the isolate.

Clinical Trials

There are no clinical trials of isolated cichoric acid. Human exposure is entirely as a dietary phenolic (chicory, lettuce, Echinacea foods/teas) or as the standardisation marker in Echinacea supplements, whose trials test the whole extract, not the molecule.

Last checked: July 2026.

Isolate vs. Plant Studies

Cichoric acid splits cleanly by application. The antiviral (HIV-1 integrase) and antioxidant/AMPK work is genuine isolated-molecule science — pure L-chicoric acid and synthetic dicaffeoyltartaric analogues, with target-mapped resistance ^{4,7,8Reference 4Lin Z et al. · 1999Chicoric acid analogues as HIV-1 integrase inhibitorsView study →Reference 7Schlernitzauer A et al. · 2013Chicoric acid is an antioxidant molecule that stimulates AMP kinase pathway in L6 myotubes and extends lifespan in Caenorhabditis elegansView study →Reference 8Lee DJ · 2004Human immunodeficiency virus type 1 (HIV-1) integrase: resistance to diketo acid integrase inhibitors impairs HIV-1 replication and integration and confers cross-resistance to L-chicoric acidView study →}. That is a real strength: the mechanism is not smeared across a crude extract.

The immune/anti-inflammatory signal is more mixed — measured both on the isolate (macrophage TNF-α) and as part of whole-Echinacea activity ^{3,5Reference 3Pellati F et al. · 2005Variability in the composition of anti-oxidant compounds in Echinacea species by HPLCView study →Reference 5Stevenson LM et al. · 2005Modulation of macrophage immune responses by EchinaceaView study →} — and it is precisely here that the absorption failure was exposed: the isolate is active in the dish but does not reach the blood ^{5Reference 5Stevenson LM et al. · 2005Modulation of macrophage immune responses by EchinaceaView study →}. So the usual caveat inverts twice: the isolate evidence is stronger than typical for antiviral chemistry, yet weaker than it looks for oral use, because pharmacokinetics — not evidence quality — is the limiting step. Where cichoric acid matters most reliably is neither as isolate drug nor extract active, but as the analytical fingerprint that tells you an Echinacea product is what it claims to be ^{3,6Reference 3Pellati F et al. · 2005Variability in the composition of anti-oxidant compounds in Echinacea species by HPLCView study →Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}.

Prevalence in Nature

Cichoric acid was first identified in 1958 by Scarpati and Oriente in chicory (Cichorium intybus), the plant it is named for ^{1Reference 1Lee J · 2013Chicoric acid: chemistry, distribution, and productionView study →}. It is now reported across at least 60 plant genera and species, concentrated in the Asteraceae but also in ferns, sea grasses and other lineages ^{1Reference 1Lee J · 2013Chicoric acid: chemistry, distribution, and productionView study →}.

Its richest and most economically important sources are in the coneflowers: in Echinacea purpurea it is the predominant phenolic, ranging from as little as ~0.4 mg/g dry weight in stems up to ~38 mg/g (nearly 4%) in flower heads, with roots also rich ^{3,6Reference 3Pellati F et al. · 2005Variability in the composition of anti-oxidant compounds in Echinacea species by HPLCView study →Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}. Everyday salad and culinary plants carry meaningful amounts too — dandelion flower heads (~3-9 mg/g), chicory, lettuce and basil — which is why cichoric acid is also studied as a dietary phenolic, not only a herbal one ^{1Reference 1Lee J · 2013Chicoric acid: chemistry, distribution, and productionView study →}. Levels vary enormously with plant part, cultivar, maturity, growing conditions and — critically — post-harvest handling, since the molecule degrades enzymatically once tissue is disrupted ^{6Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}.

Major Natural Sources

Plant	Part	Typical cichoric acid	Note
Purple coneflower (Echinacea purpurea)	flower heads	up to ~38 mg/g dry wt	richest source; the QC marker
Purple coneflower (Echinacea purpurea)	root	~6-21 mg/g dry wt	predominant root phenolic
Chicory (Cichorium intybus)	leaves	variable	the namesake source (1958)
Dandelion (Taraxacum officinale)	flower heads	~3-9 mg/g dry wt	dietary phenolic
Lettuce (Lactuca sativa)	leaves	cultivar-dependent	up to ~1.4 mg/g fresh wt
Basil (Ocimum basilicum)	leaves	~0.03-2.8 mg/g dry wt	~90-fold cultivar variation

Note that E. angustifolia and E. pallida roots are characterised instead by echinacoside, not cichoric acid — the marker set is species-specific, which is itself a taxonomic and QC discriminator.

Discovery & Synthesis

Cichoric acid was first identified in 1958 by the Italian chemists Scarpati and Oriente, who isolated it from chicory (Cichorium intybus) and named it after the plant’s genus ^{1Reference 1Lee J · 2013Chicoric acid: chemistry, distribution, and productionView study →}. It was then largely overlooked for decades — a minor curiosity of chicory chemistry — until two developments revived interest: its adoption as the standardisation marker for Echinacea purpurea ^{3,6Reference 3Pellati F et al. · 2005Variability in the composition of anti-oxidant compounds in Echinacea species by HPLCView study →Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}, and the late-1990s discovery that L-chicoric acid inhibits HIV-1 integrase ^{4Reference 4Lin Z et al. · 1999Chicoric acid analogues as HIV-1 integrase inhibitorsView study →}.

For synthesis, the earliest dedicated total synthesis is not well documented as a landmark; in practice L-chicoric acid and a series of dicaffeoyltartaric-acid analogues were prepared synthetically during the HIV-1 integrase medicinal-chemistry campaigns of the late 1990s, which is where most of the pure-compound structure-activity work originates ^{4Reference 4Lin Z et al. · 1999Chicoric acid analogues as HIV-1 integrase inhibitorsView study →}. Because the ester-linked di-catechol is straightforward to assemble by coupling protected caffeic acid to tartaric acid, synthetic material has been the norm for mechanistic studies, while extraction from Echinacea or chicory supplies the analytical-standard and supplement-marker demand. Given the molecule’s enzymatic instability, commercial isolation is as much about stabilised processing (antioxidant/inert-atmosphere extraction) as about yield ^{6Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}.

Patents: not yet researched.

Toxicity & Safety

Cichoric acid carries a low toxicity flag. It is a dietary phenolic consumed routinely in chicory, lettuce, dandelion and Echinacea foods and teas, with a long history of ordinary human exposure and no signal of notable toxicity. Its very poor absorption further limits any systemic effect from oral intake ^{5Reference 5Stevenson LM et al. · 2005Modulation of macrophage immune responses by EchinaceaView study →}.

Safety at a Glance

✅ Low / no toxicity

• Ordinary dietary phenolic. Consumed in chicory, lettuce, dandelion and Echinacea preparations with no established toxicity concern; a natural constituent of common foods.
• Minimal systemic exposure. Poorly absorbed and undetectable in plasma after oral intake, so systemic risk from the isolated molecule is low ^{5Reference 5Stevenson LM et al. · 2005Modulation of macrophage immune responses by EchinaceaView study →}.
• Echinacea-level cautions apply, not molecule-level ones. Safety decisions about Echinacea products (allergy in atopic/asthmatic individuals, autoimmune-disease caution, pregnancy/lactation) belong to the herb and product pages, where intake is decided — not to this phytochemistry page.
• No dedicated isolate toxicology. No comprehensive genotoxicity, reproductive or repeat-dose dataset exists for purified cichoric acid; absence of findings is not evidence of safety.

Drug-interaction data specific to isolated cichoric acid are not established. The HIV-1 integrase and antiviral results are in-vitro mechanistic findings, not evidence that dietary or supplemental cichoric acid affects viral infection or antiviral drug therapy in people, and should not be read that way.

Dosage

There is no established therapeutic dose for isolated cichoric acid, and — given its poor oral absorption — no rationale for one has been demonstrated in humans ^{5Reference 5Stevenson LM et al. · 2005Modulation of macrophage immune responses by EchinaceaView study →}. Real-world exposure comes in two forms:

• Dietary: as a phenolic in chicory, lettuce, dandelion, basil and Echinacea foods and teas, at the milligram-per-gram levels above.
• As an Echinacea quality marker: commercial E. purpurea products are frequently standardised to a stated cichoric-acid content (often on the order of ~2-4% of the extract). This is a specification for identity and potency, and a proxy for correct handling — not a dose target for the isolated molecule ^{3,6Reference 3Pellati F et al. · 2005Variability in the composition of anti-oxidant compounds in Echinacea species by HPLCView study →Reference 6Nüsslein B et al. · 2000Enzymatic degradation of cichoric acid in Echinacea purpurea preparationsView study →}.

These are dietary and quality-control figures, not a personal recommendation.

References

1. Lee J, Scagel CF (2013). Chicoric acid: chemistry, distribution, and production. Frontiers in Chemistry. https://pubmed.ncbi.nlm.nih.gov/24790967/
2. Robinson WE Jr (1998). L-chicoric acid, an inhibitor of human immunodeficiency virus type 1 (HIV-1) integrase, improves on the in vitro anti-HIV-1 effect of Zidovudine plus a protease inhibitor (AG1350). Antiviral Research. https://pubmed.ncbi.nlm.nih.gov/9806487/
3. Pellati F, Benvenuti S, Melegari M, Lasseigne T (2005). Variability in the composition of anti-oxidant compounds in Echinacea species by HPLC. Phytochemical Analysis. https://pubmed.ncbi.nlm.nih.gov/15881113/
4. Lin Z, Neamati N, Zhao H, et al. (1999). Chicoric acid analogues as HIV-1 integrase inhibitors. Journal of Medicinal Chemistry. https://pubmed.ncbi.nlm.nih.gov/10212126/
5. Stevenson LM, Matthias A, Banbury L, et al. (2005). Modulation of macrophage immune responses by Echinacea. Molecules. https://pubmed.ncbi.nlm.nih.gov/18007520/
6. Nüsslein B, Kurzmann M, Bauer R, Kreis W (2000). Enzymatic degradation of cichoric acid in Echinacea purpurea preparations. Journal of Natural Products. https://pubmed.ncbi.nlm.nih.gov/11141099/
7. Schlernitzauer A, Oiry C, Hamad R, et al. (2013). Chicoric acid is an antioxidant molecule that stimulates AMP kinase pathway in L6 myotubes and extends lifespan in Caenorhabditis elegans. PLoS One. https://pubmed.ncbi.nlm.nih.gov/24244361/
8. Lee DJ, Robinson WE Jr (2004). Human immunodeficiency virus type 1 (HIV-1) integrase: resistance to diketo acid integrase inhibitors impairs HIV-1 replication and integration and confers cross-resistance to L-chicoric acid. Journal of Virology. https://pubmed.ncbi.nlm.nih.gov/15140981/
9. Beale KK, Robinson WE Jr (2000). Combinations of reverse transcriptase, protease, and integrase inhibitors can be synergistic in vitro against drug-sensitive and RT inhibitor-resistant molecular clones of HIV-1. Antiviral Research. https://pubmed.ncbi.nlm.nih.gov/10867160/

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