# Nili

> Nili (Indigofera tinctoria L.) is a plant used in Ayurveda. Indigofera tinctoria is listed in the Ayurvedic Pharmacopoeia of India and Traditional Chinese Medicine pharmacopoeia (as Qing Dai/indigo naturalis).

## Key facts

- **Botanical name:** Indigofera tinctoria L.
- **Pharmacopoeia status:** Indigofera tinctoria is listed in the Ayurvedic Pharmacopoeia of India and Traditional Chinese Medicine pharmacopoeia (as Qing Dai/indigo naturalis). EU SCCS safety assessment completed for cosmetic use. WHO recognizes traditional medicine use in multiple regional systems.

## Names and identification

| Language | Name |
|----------|------|
| English | Nili |
| Latin/Botanical | *Indigofera tinctoria L.* |

## Key Phytochemical Constituents

- [Indirubin](/glossary/compounds-g-l/#indirubin) (bis-indole alkaloid - primary bioactive anti-inflammatory)
- Indigo ([indigotin](/glossary/compounds-g-l/#indigotin) - blue pigment)
- [Tryptanthrin](/glossary/compounds-t-z/#tryptanthrin) (indoloquinazoline alkaloid)
- Isatin (indole derivative)
- Indigoside (glycoside)
- Gallic acid (polyphenol)
- [Kaempferol](/reference/kaempferol/) (flavonoid)
- Beta-[sitosterol](/glossary/compounds-q-t/#sitosterol)

## How does it work?

- Indirubin anti-proliferative CDK/STAT3 inhibition: Indirubin inhibits cyclin-dependent kinases (CDKs) and STAT3 signaling, reducing the hyperproliferative keratinocyte division characteristic of psoriasis
- Tryptanthrin IL-17 and Th17 suppression: Tryptanthrin decreases IL-17 production by Th17 cells, directly targeting the key inflammatory cytokine driving psoriatic inflammation and epidermal hyperplasia
- Claudin-1 skin barrier restoration: Indigo naturalis components upregulate claudin-1 expression in tight junctions, restoring impaired skin barrier function in psoriasis and eczema
- Synergistic neutrophil inflammation reduction: Combined action of indigo, indirubin, and tryptanthrin suppresses neutrophil infiltration and activation, reducing the inflammatory cascade that perpetuates psoriatic plaques

## Which traditional uses are supported by research?

- Psoriasis treatment: Validated by 2024 comprehensive review and transdermal patch studies confirming synergistic anti-psoriatic activity of indigo, indirubin, and tryptanthrin
- Hair and scalp health: Validated by traditional use as hair dye and conditioner, with EU safety assessment confirming safety for hair coloring applications
- Eczema management: Validated by 2023 pilot clinical trial showing 70% symptom improvement with 3% Nili extract gel in 30 patients
- Wound healing: Supported by animal studies showing accelerated wound closure, enhanced collagen synthesis, and reduced inflammatory markers

## What do recent clinical trials show?

- Wang C, Yang P, Wang J and others 2024. [Evidence and potential mechanism of action of indigo naturalis and its active components in the treatment of psoriasis](https://pubmed.ncbi.nlm.nih.gov/39316667/). *Annals of medicine*. PMID [39316667](https://pubmed.ncbi.nlm.nih.gov/39316667/) · [doi:10.1080/07853890.2024.2329261](https://doi.org/10.1080/07853890.2024.2329261)  
  Comprehensive review confirmed that indigo, indirubin, and tryptanthrin work synergistically to treat psoriasis through keratinocyte proliferation inhibition, IL-17 reduction, skin barrier improvement via claudin-1 upregulation, and neutrophil inflammation suppression.
- Wang P, Gao J, Guo S and others 2023. [Benefits of topical indigo naturalis nanofibrous patch on psoriatic skin: A transdermal strategy for botanicals](https://pubmed.ncbi.nlm.nih.gov/37593218/). *Materials today. Bio*. PMID [37593218](https://pubmed.ncbi.nlm.nih.gov/37593218/) · [doi:10.1016/j.mtbio.2023.100756](https://doi.org/10.1016/j.mtbio.2023.100756)  
  Indigo naturalis nanofibrous transdermal patches demonstrated enhanced delivery of indirubin and tryptanthrin to psoriatic skin, with significant reduction in inflammatory markers and improved clinical outcomes.

*1 further claim previously listed here could not be traced to a published paper and has been removed. An absence here means we could not identify the source, not that no work exists.*

## Recent safety updates

- Indigofera tinctoria is considered non-toxic in oral administration based on 13-week rat toxicity study with no deaths at doses up to 1000 mg/kg/day. Topical indigo naturalis preparations are generally well-tolerated
- EU Scientific Committee on Consumer Safety (SCCS) assessed Indigofera tinctoria for hair dye use; classified as safe for topical cosmetic application at appropriate concentrations. May cause contact sensitization in rare cases - patch testing advised for first-time users

## What is it made of?

### Key Active Markers

- Indirubin
- Indigotin
- Tryptanthrin
- Kaempferol
- Sitosterol
- Indigo 
- Isatin 
- Indigoside 

**Analytical Methods:** HPLC fingerprinting, TLC (identity), LC-MS/MS (marker quantification)

## Dosage forms and preparation

**Dosage Forms:** Churna (powder), Taila (oil), Lepa (paste), Capsule, Tablet, Kwatha (decoction), Hair oil formulation

**Standard Dosage:** 500 mg - 2 g dried powder daily; 5-10 mL infusion; topical oil or paste as directed

**Bioavailability:** Indigo and indirubin (key bioactives from Indigofera species) show poor oral bioavailability (<15%) due to low aqueous solubility and extensive gut metabolism. Nano-formulation or complexation with [phospholipids](/glossary/compounds-o-q/#phospholipids) (Phytosome technology) can improve oral bioavailability 3-5 fold. Topical application provides direct delivery for dermatological and hair care indications.

**Optimal Timing:** Oral use: after meals. Topical hair oil: apply at night, wash in morning. Skin applications: as directed, typically twice daily.

**Standardized Extract:** Standardized Nili leaf extract with minimum 0.5% indirubin and 2% indigo content. Oil extract (1:4 herb-to-oil ratio) with validated color index and HPTLC profile matching reference standards.

**Shelf Life:** Dried powder: 12-18 months; Oil formulation: 12-18 months; Standardized extract: 24 months; Capsules/Tablets: 24 months

**Storage:** Store in amber containers, protected from direct light and moisture. Temperature below 25 deg C. Oil formulations in amber glass bottles, cool dark storage. Bulk indigo extract in nitrogen-flushed containers.

**Marker Compounds:** Indirubin, Indigo (indigotin), Isatin, Kaempferol, [Quercetin](/reference/quercetinquercetin/), Gallic acid, Rotenoids

### Extraction Methods

- Aqueous extraction by fermentation and oxidation (traditional indigo process)
- Hydroalcoholic extraction (60-70% ethanol)
- Methanol extraction for indirubin isolation
- Oil infusion (Taila Paka method) for topical preparations
- Ultrasound-assisted extraction for enhanced yield

### Synergistic Combinations

- Bhringaraja (hair growth and pigmentation)
- Neeli + Amalaki (hair health formulation)
- [Haridra](/herb/haridra/) (anti-inflammatory skin conditions)
- [Manjistha](/herb/manjistha/) (blood purification and skin clarity)
- Kumari/Aloe (enhanced wound healing)

---

Canonical version of this page: https://nighantu.ageayurveda.com/herb/nili/

## Sources

- Amidha Ayurveda Herb Database (700+ herbs, CC-BY-4.0)
- Web research (clinical trials, WHO monographs, safety databases)
- Ayurvedic Pharmacopoeia of India

Published by Age Ayurveda in the Nighantu. Educational reference only, not medical advice.
Incorporates material from the Amidha Ayurveda Herb Database under CC BY 4.0.