# Palandu

> Palandu (Allium cepa) is a plant used in Ayurveda. Allicin and thiosulfinates are rapidly absorbed but quickly metabolized to diallyl sulfides. S-allyl cysteine shows >90% oral bioavailability. Cooking reduces quercetin content by 20-30% but may improve digestibility.

## Key facts

- **Botanical name:** Allium cepa

## Names and identification

| Language | Name |
|----------|------|
| English | Palandu |

## Ayurvedic pharmacology (Dravyaguna)

| Property | Value | Description |
|----------|-------|-------------|
| **Rasa** (Taste) | Madhura, Katu | Primary taste |
| **Guna** (Quality) | Guru, Snigdha | Physical quality |
| **Virya** (Potency) | Ushna | Heating/Cooling effect |
| **Vipaka** (Post-digestive) | Madhura | Post-digestive effect |

## Dosage forms and preparation

**Dosage Forms:** Fresh juice (Swarasa), Capsule, Tablet, Soft gel (oil extract), Powder (dehydrated), Syrup, Ear drops, Poultice

**Standard Dosage:** 5-15 mL fresh onion juice daily; 500-1000 mg dried onion extract daily; 1-3 g dehydrated onion powder daily

**Bioavailability:** [Quercetin](/reference/quercetinquercetin/) from onion is among the most bioavailable dietary sources (~50-65% absorption) due to the presence of [quercetin](/reference/quercetinquercetin/) glucosides (especially quercetin-4'-glucoside) which are actively transported by SGLT1 in the small intestine. [Allicin](/glossary/compounds-1-a/#allicin) and thiosulfinates are rapidly absorbed but quickly metabolized to diallyl sulfides. S-allyl cysteine shows >90% oral bioavailability. Cooking reduces quercetin content by 20-30% but may improve digestibility.

**Optimal Timing:** Fresh juice: morning on empty stomach or with meals. Supplements: with meals to reduce GI irritation and improve quercetin absorption with dietary fat. Ear drops: as directed by practitioner.

**Standardized Extract:** Standardized onion extract with quercetin >8% (as quercetin glucosides), total thiosulfinates >1%. Dehydrated onion powder retaining >70% of fresh quercetin content.

**Shelf Life:** Fresh juice: 4-8 hours unpreserved; Dehydrated powder: 12-18 months; Standardized extract: 24 months; Capsules: 24 months; Freeze-dried powder: 24-36 months

**Storage:** Fresh onion juice: refrigerated 2-8 deg C, use immediately. Dried forms: below 25 deg C, RH <40%, moisture-barrier packaging. Protect from light (quercetin photodegradation). Enteric-coated products in blister packs to prevent moisture ingress.

**Marker Compounds:** Quercetin, Quercetin-4'-glucoside, Quercetin-3,4'-diglucoside, Allicin, S-allyl cysteine, Diallyl disulfide, [Kaempferol](/reference/kaempferol/), [Isorhamnetin](/glossary/compounds-g-l/#isorhamnetin)

### Extraction Methods

- Fresh mechanical juice extraction
- Aqueous extraction followed by spray drying
- Hydroalcoholic extraction (30-50% ethanol) for quercetin-rich fractions
- Steam distillation for volatile sulfur compounds
- Freeze-drying of juice for maximum bioactive retention
- Enzymatic extraction for enhanced yield

### Synergistic Combinations

- Rasona/Garlic (cardiovascular synergy - combined allium formulation)
- [Haridra](/herb/haridra/) (anti-inflammatory combination)
- [Methi](/herb/methi/)/Fenugreek (blood sugar management)
- [Madhu](/herb/madhu/)/Honey (cough and cold remedy)
- Adrak/[Ginger](/herb/ginger/) (digestive and anti-inflammatory)

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

## Sources

- Amidha Ayurveda Herb Database (700+ herbs, CC-BY-4.0)
- 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.