# Turmeric (curcuma longa) rhizome essential oil: analytical profile of authenticated and commercial samples, safety and pharmacology review

## TL;DR

This study analyzes the composition and safety of turmeric rhizome essential oil, highlighting variability in commercial products and its potential therapeutic benefits.

## Contribution

The study provides a detailed analytical profile and safety review of authentic and commercial turmeric essential oils.

## Key findings

- Turmeric essential oil is mainly composed of turmerones, with compositional differences between fresh and ground rhizomes.
- Some commercial samples showed signs of adulteration or dilution, affecting product consistency.
- The oil exhibits anti-inflammatory, antimicrobial, and anticancer properties with a favorable safety profile.

## Abstract

Turmeric (Curcuma longa) rhizome essential oil is the volatile and aromatic fraction of turmeric rhizome. Despite increasing commercial availability and scientific interest, variability in production practices and oil composition has created challenges for quality, safety, and pharmacological interpretation.

This work provides a comprehensive overview of turmeric rhizome essential oil including an assessment of the composition of authentic oils, and commercial oils, and a review of safety and pharmacology.

Authentic samples from India (n = 35) and Nepal (n = 15), and market samples (n = 25) were analyzed by GC-MS. A review of published toxicological and pharmacological studies was conducted.

Authenticated oils were primarily composed of turmerones. Sesquiterpenes were more abundant in the oil from ground material, whereas monoterpenes were more prevalent in the oil from fresh rhizomes. Most market samples also exhibited the large dominance of turmerones, with some showing compositional variability, dilution, or adulteration, including 4/25 samples containing adulteration markers. Toxicological studies indicate no genotoxicity or dermal toxicity, minimal systemic toxicity, and good tolerability in humans. The pharmacology data supports anti-inflammatory, antimicrobial, neuroprotective, antioxidant, and anticancer properties, with synergistic effects when turmerones and curcuminoids are combined.

Turmeric rhizome essential oil demonstrated a favorable safety profile and diverse bioactivities with therapeutic potential. However, compositional variation in commercial products with adulteration highlights the need for production standards. Authentic and consistent essential oil composition is key to ensure reproducible research findings, validate therapeutic potential, guarantee safety and provide the desirable outcomes when used.