# Dyer's Woad (Isatis tinctoria)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/dyer-s-woad
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-04-01
**Evidence Score:** 2 / 10
**Category:** Traditional Chinese Medicine
**Also Known As:** Isatis tinctoria, Woad, Dyer's Weed, Asp of Jerusalem, Glastum, European Woad, Common Woad, Ban Lan Gen, Da Qing Ye

## Overview

Dyer's Woad (Isatis tinctoria) is a flowering plant used in Traditional Chinese Medicine whose primary bioactive compounds include tryptanthrin and indirubin. These alkaloids exert [antiviral](/ingredients/condition/immune-support), [anti-inflammatory](/ingredients/condition/inflammation), and antineoplastic effects largely by inhibiting key inflammatory enzymes and modulating cell cycle progression.

## Health Benefits

• [Antiviral](/ingredients/condition/immune-support) properties: Demonstrated in vitro, but no human trials available.
• Antibacterial effects: Evident in preclinical studies.
• [Anti-inflammatory](/ingredients/condition/inflammation) potential: Tryptanthrin inhibits COX-2 and 5-LOX in vitro.
• Antineoplastic activity: Suggested by animal studies.
• Antifungal action: Observed in lab settings, yet unverified in humans.

## Mechanism of Action

Tryptanthrin, an alkaloid derived from Isatis tinctoria, inhibits cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX), thereby reducing synthesis of [prostaglandin](/ingredients/condition/inflammation)s and leukotrienes that drive inflammatory cascades. Indirubin, another key compound, inhibits cyclin-dependent kinases (CDKs) and glycogen synthase kinase-3 beta (GSK-3β), disrupting tumor cell proliferation and inducing apoptosis. [Antiviral](/ingredients/condition/immune-support) activity is attributed to multiple constituents interfering with viral replication mechanisms, though the precise receptor-level targets in human cells remain incompletely characterized.

## Clinical Summary

The evidence base for Isatis tinctoria relies predominantly on in vitro cell studies and animal models, with no well-designed randomized controlled human trials published to date. Preclinical studies have demonstrated antibacterial activity against pathogens including Staphylococcus aureus and antifungal effects in laboratory settings, though effect sizes are not yet translated to validated clinical doses. Antineoplastic activity observed in rodent models involves indirubin-mediated CDK inhibition, but human pharmacokinetic and efficacy data are absent. Overall, the evidence is early-stage and insufficient to make clinical recommendations without further rigorous investigation.

## Nutritional Profile

Dyer's Woad (Isatis tinctoria) is a medicinal herb rather than a dietary staple, so its nutritional profile is characterized primarily by bioactive compounds rather than significant macronutrient content. Dried leaf material contains approximately 10–15% protein by dry weight, with a modest fiber content of roughly 20–25% (predominantly cellulose and hemicellulose from plant cell walls). Fat content is minimal, estimated below 3% dry weight. Carbohydrates constitute the largest macronutrient fraction at approximately 40–50% dry weight, largely structural polysaccharides. Key bioactive compounds include: Indigo (indigotin) at concentrations of 0.2–0.8% in dried leaves, and indirubin at lower concentrations of 0.01–0.1%, both being bis-indole alkaloid pigments with documented pharmacological activity. Tryptanthrin (indolo[2,1-b]quinazoline-6,12-dione) is present at approximately 0.01–0.05% dry weight and is considered a primary [anti-inflammatory](/ingredients/condition/inflammation) and antineoplastic agent. Isatin (2,3-dioxoindoline) occurs at trace levels (~0.005–0.02%). Glucosinolates, particularly glucobrassicin and its derivatives, are present at 1–5 µmol/g dry weight, consistent with its Brassicaceae family membership. Sinigrin has been identified in root preparations. Polysaccharides (notably arabinogalactans and rhamnogalacturonans) from the root (Ban Lan Gen) are present at 5–15% dry weight and are associated with [immunomodulatory](/ingredients/condition/immune-support) activity. Flavonoids including clemastanin B and lariciresinol are detectable at low concentrations (~0.01–0.05%). Amino acid content includes tryptophan and its metabolic derivatives, which serve as biosynthetic precursors to the indole-based bioactives. Mineral content includes moderate levels of potassium (~1,500–2,500 mg/100g dry weight), calcium (~800–1,200 mg/100g dry weight), and iron (~15–30 mg/100g dry weight), though bioavailability of minerals is reduced by the presence of glucosinolate-derived compounds and fiber matrix. Vitamin C has been detected in fresh leaf tissue (~30–60 mg/100g fresh weight) but degrades substantially during drying and processing. Bioavailability of tryptanthrin and indigo is limited by poor aqueous solubility; lipid-based delivery or ethanol extraction significantly enhances absorption. Most pharmacokinetic data are derived from animal models, and human bioavailability data remain sparse.

## Dosage & Preparation

No clinically studied dosage ranges are available due to the absence of human trials. Preclinical screenings have been conducted, but without standardized human doses. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Isatis tinctoria is generally considered low-risk at traditional doses, but high or prolonged intake of indirubin-containing preparations has been associated with gastrointestinal disturbances including nausea and diarrhea in case reports. Because tryptanthrin inhibits COX-2 pathways similarly to NSAIDs, concurrent use with nonsteroidal [anti-inflammatory](/ingredients/condition/inflammation) drugs or anticoagulants such as warfarin may theoretically potentiate bleeding risk. Indirubin's CDK-inhibitory activity raises theoretical concerns about interactions with chemotherapy agents, and use alongside cytotoxic drugs should be medically supervised. Safety data in pregnant or breastfeeding women is lacking, and use in these populations is not recommended.

## Scientific Research

There are no human clinical trials or meta-analyses available for Dyer's Woad. The existing evidence is derived from in vitro and animal studies, with no PMIDs for human studies.

## Historical & Cultural Context

Historically, Isatis tinctoria has been cultivated for its indigo dye production, a practice that dates back over a millennium in European traditions. Its phytopharmacological potential is recognized, but traditional medicinal uses are not well-documented beyond dye production.

## Synergistic Combinations

Tryptophan, Calcium Hydroxide, Citric Acid, Glucosinolates, Flavonoids

## Frequently Asked Questions

### What is tryptanthrin and why is it important in Dyer's Woad?

Tryptanthrin is an indoloquinazoline alkaloid found in Isatis tinctoria that directly inhibits the inflammatory enzymes COX-2 and 5-lipoxygenase, reducing production of prostaglandins and leukotrienes. It is considered one of the primary bioactive compounds responsible for the plant's anti-inflammatory and antiviral properties observed in laboratory studies. No clinical trials have yet established an effective human dose for tryptanthrin specifically.

### Does Dyer's Woad have proven antiviral effects in humans?

Antiviral activity of Isatis tinctoria has been demonstrated in multiple in vitro studies against viruses including influenza and certain herpes strains, but no controlled human clinical trials have confirmed these effects in people. The gap between cell-culture findings and human efficacy is significant, as bioavailability and pharmacokinetics in vivo have not been adequately characterized. Until human trials are conducted, antiviral claims remain preclinical and should not be used as a basis for treatment.

### What is indirubin and how does it relate to cancer research?

Indirubin is a bis-indole compound present in Isatis tinctoria that inhibits cyclin-dependent kinases (CDK1, CDK2, CDK5) and GSK-3β, disrupting cancer cell cycle progression and promoting apoptosis. It gained research attention partly because of its structural similarity to staurosporine and has been studied in animal tumor models showing reduced tumor growth. However, human clinical evidence for indirubin as an antineoplastic agent from Dyer's Woad specifically is currently absent.

### Are there any known drug interactions with Dyer's Woad supplements?

Dyer's Woad may interact with NSAIDs and anticoagulants like warfarin due to tryptanthrin's COX-2 inhibitory activity, potentially increasing bleeding risk when combined. Indirubin's inhibition of CDKs also raises concern about additive or antagonistic effects when used alongside conventional chemotherapy agents. Patients on immunosuppressants, blood thinners, or cancer medications should consult a healthcare provider before use.

### How was Dyer's Woad traditionally used in Chinese Medicine?

In Traditional Chinese Medicine, Dyer's Woad is used in two primary forms: Ban Lan Gen (the root) and Da Qing Ye (the leaf), both classified as 'cold' herbs used to clear heat and resolve toxicity. These preparations have historically been prescribed for febrile illnesses, sore throats, and viral infections such as influenza and mumps. The traditional applications broadly align with the antiviral and anti-inflammatory properties identified in modern preclinical research, though TCM dosing protocols differ from standardized supplement formats.

### What is the difference between Dyer's Woad extract and whole leaf powder in terms of active compound concentration?

Dyer's Woad extracts are concentrated to deliver higher levels of bioactive compounds like tryptanthrin and indirubin compared to whole leaf powder, which contains these constituents at naturally lower concentrations. Extract forms typically provide more standardized dosing of active ingredients, whereas whole leaf powder offers the full spectrum of plant compounds but requires larger doses to achieve equivalent potency. The choice between forms depends on whether concentrated bioactive delivery or whole-plant synergy is the priority for your supplementation goals.

### Is Dyer's Woad safe to use during pregnancy and breastfeeding?

There is insufficient clinical data on Dyer's Woad safety during pregnancy and breastfeeding, and it is not recommended for these populations due to its bioactive compounds and lack of human safety studies in these vulnerable groups. Traditional use in Chinese medicine does not constitute proof of safety during gestation or lactation, as historical practices were not designed with modern pregnancy standards in mind. Pregnant and nursing women should consult a healthcare provider before considering Dyer's Woad supplementation.

### What does current research show about Dyer's Woad's effectiveness compared to its traditional reputation?

Most research on Dyer's Woad has been conducted in vitro or in animal models, showing promising antibacterial, antiviral, and anti-inflammatory effects that align with its traditional use, but human clinical trials remain limited or absent. The gap between preclinical evidence and proven human efficacy means traditional claims cannot yet be fully validated in modern clinical settings. While the scientific foundation is encouraging, consumers should understand that supplement marketing often exceeds the current strength of human evidence.

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