# Eucalyptus camaldulensis (Eucalyptus camaldulensis Dehnh.)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/eucalyptus-camaldulensis-eucalyptus-camaldulensis-dehnh
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-04-02
**Evidence Score:** 1 / 10
**Category:** Middle Eastern
**Also Known As:** Red Gum Eucalyptus, Eucalyptus camaldulensis Dehnh., Eucalyptus rostrata Schlecht., Kah-weet (Aboriginal), River Red Gum, Murray Red Gum, Eucalipto rojo, Eucalyptus camaldulensis (River Red Gum)

## Overview

Eucalyptus camaldulensis leaves concentrate 1,8-cineole (eucalyptol, up to 84.9% of essential oil) alongside ellagitannins such as tellimagrandin I and vescalagin, which together disrupt microbial membranes, inhibit key enzymes, and scavenge [free radical](/ingredients/condition/antioxidant)s through electron/hydrogen donation. In vitro studies demonstrate up to 90% DPPH radical inhibition at 500 µg/mL and [antimicrobial](/ingredients/condition/immune-support) activity attributed to cineole-driven membrane disruption, though no human clinical trials have yet quantified these effects in therapeutic endpoints.

## Health Benefits

- **[Antimicrobial](/ingredients/condition/immune-support) and Anti-tuberculosis Activity**: Leaf essential oil dominated by 1,8-cineole (average 77%) disrupts the lipid membranes of bacterial pathogens, and the plant is used in Middle Eastern herbalism specifically for respiratory infections including tuberculosis, supported by in vitro inhibitory data.
- **[Antioxidant Protection](/ingredients/condition/antioxidant)**: Methanolic and acetone leaf extracts containing total polyphenols of 364.1 ± 8.2 mg GAE/g and flavonoids at 80.5 ± 0.9 mg QE/g achieve up to 90% DPPH radical scavenging inhibition at 500 µg/mL, indicating robust free-radical neutralization capacity.
- **Antiviral Potential**: Ellagitannins including tellimagrandin I (active at 1.45 µg/mL, 71.47 ± 5.64% inhibition) and vescalagin/castalagin exhibit enzyme-inhibitory and membrane-disruptive antiviral mechanisms in cell-based assays, suggesting utility against viral pathogens.
- **[Anti-inflammatory](/ingredients/condition/inflammation) Effects**: Quercetin glucuronide (5.15% of flavonoid fraction) and kaempferol glucuronide (3.36%) contribute to anti-inflammatory signaling by modulating pro-inflammatory enzyme pathways, consistent with the broader anti-inflammatory pharmacology of flavonoid glucuronides.
- **Cytotoxic and Anticancer Properties**: Leaf extracts induce 16–44% cell death in tumor cell lines at concentrations of 20–120 µg/mL in vitro, attributed to the combined action of ellagitannins and flavonoids interfering with cellular proliferation pathways.
- **Wound Healing and Astringent Action**: Kino exudate from the bark contains up to 45% kinotannic acid and 76.7% total tannins, which are applied topically in traditional practice to contract tissue, reduce microbial load, and support wound healing through protein-precipitating astringency.
- **Respiratory Mucolytic Support**: Inhalation or steam preparations of the essential oil deliver 1,8-cineole directly to bronchial mucosa, where it acts as a mucolytic and bronchodilatory agent consistent with the well-characterized pharmacology of eucalyptol in respiratory conditions.

## Mechanism of Action

1,8-Cineole (eucalyptol), comprising up to 84.9% of the essential oil, intercalates into and disorders phospholipid bilayers of bacterial and fungal cell membranes, increasing permeability and causing leakage of cellular contents, while also inhibiting cholinesterase and modulating NF-κB-mediated [inflammatory](/ingredients/condition/inflammation) signaling. Ellagitannins—specifically tellimagrandin I, pedunculagin, vescalagin, and castalagin—inhibit viral and bacterial enzymes likely through binding to active-site residues via multiple hydroxyl-mediated hydrogen bonds and hydrophobic interactions, with tellimagrandin I demonstrating 71.47 ± 5.64% target inhibition at 1.45 µg/mL. Polyphenols including quercetin glucuronide and kaempferol glucuronide donate electrons and hydrogen atoms to neutralize DPPH, ABTS, and superoxide radicals (15–75% superoxide quenching at 100–500 µg/mL), while also chelating transition metals to suppress Fenton-type oxidative chemistry via ferric-reducing (FRAP) mechanisms. Tannins (5–11% in leaves, up to 16% in bark) precipitate surface proteins on microbial cells and host tissue, contributing both to [antimicrobial](/ingredients/condition/immune-support) membrane disruption and the astringent wound-healing effects observed with kino preparations.

## Clinical Summary

No controlled human clinical trials have been conducted specifically with Eucalyptus camaldulensis extracts or essential oil as primary interventions, representing a significant evidence gap for a widely used traditional herb. Available in vitro outcomes—including 90% DPPH inhibition at 500 µg/mL, 71.47% enzyme inhibition by tellimagrandin I at 1.45 µg/mL, and 16–44% tumor cell cytotoxicity at 20–120 µg/mL—provide mechanistic signals but cannot be directly extrapolated to human efficacy or safety without bioavailability data. Some indirect clinical evidence exists for 1,8-cineole (eucalyptol) as a class compound from studies on Eucalyptus globulus and purified eucalyptol preparations, suggesting mucolytic and [anti-inflammatory](/ingredients/condition/inflammation) benefits in respiratory conditions, but these findings cannot be uncritically attributed to E. camaldulensis formulations. Confidence in clinical efficacy is therefore low; the ingredient merits Phase I and Phase II investigation to establish pharmacokinetics, effective human doses, and validated clinical endpoints.

## Nutritional Profile

Eucalyptus camaldulensis leaves are not consumed as a food and do not contribute macronutrients (protein, carbohydrate, fat) or conventional micronutrients (vitamins, minerals) in meaningful quantities in herbal use contexts. Phytochemically, dried leaves contain total polyphenols at 364.1 ± 8.2 mg GAE/g dry weight and total flavonoids at 80.5 ± 0.9 mg QE/g, representing an exceptionally polyphenol-rich matrix. Ellagitannins (tellimagrandin I, pedunculagin, vescalagin at 5 mg/mL, castalagin at 4 mg/mL) and tannins (5–11% of leaf dry weight, 2.5–16% in bark) dominate the phenolic fraction, alongside key flavonoids quercetin glucuronide (5.15%) and kaempferol glucuronide (3.36%). The essential oil fraction (0.1–0.4% yield) is rich in terpenoids: 1,8-cineole (13.73–84.9%), α-pinene (up to 15%), spathulenol (0.16–19.2%), trans-pinocarveol (0.06–8.5%), terpinen-4-ol (0.27–5.2%), and myrtenol (1.4–9.75%); bioavailability of phenolics is expected to be moderate and dependent on [gut microbiome](/ingredients/condition/gut-health) [metabolism](/ingredients/condition/weight-management) of ellagitannins to urolithins.

## Dosage & Preparation

- **Essential Oil (Steam Distillation)**: Yield 0.1–0.4% from fresh leaves; no standardized therapeutic dose established; aromatherapy inhalation typically uses 2–5 drops in a diffuser or steam bowl; standardization to ≥70% 1,8-cineole is recommended for consistency.
- **Methanolic/Acetone Leaf Extract**: Research extracts prepared at 60% methanol or acetone used at 100–500 µg/mL in vitro; equivalent human dose not established; traditionally prepared as a decoction using 5–10 g dried leaves per 250 mL water.
- **Aqueous Decoction (Traditional)**: Leaves boiled for 10–15 minutes; used in Middle Eastern folk medicine as a tea or inhalant steam for respiratory conditions; no standardized dosing validated in clinical trials.
- **Kino Exudate (Topical)**: Bark exudate containing 45% kinotannic acid applied directly to wounds or oral mucosa as an astringent; concentration and frequency not clinically standardized.
- **Nanoemulsion Formulations**: Experimental preparations identifying 20 volatile compounds (93.52% volatiles) show promise for enhanced bioavailability; currently pre-clinical only.
- **Timing Note**: Traditional use suggests morning inhalation or decoction use; no chronopharmacological data available to guide optimal dosing timing.

## Safety & Drug Interactions

No formal human safety studies, toxicology trials, or established maximum safe doses exist specifically for Eucalyptus camaldulensis preparations, representing a critical data gap; users and practitioners should exercise caution in the absence of clinical safety data. The high tannin content (up to 11% in leaves and 76.7% in kino) poses a plausible risk of gastrointestinal irritation, nausea, and constipation at high oral doses, and prolonged high-tannin intake may theoretically impair iron and protein absorption by forming insoluble complexes. Essential oil containing high 1,8-cineole concentrations is toxic if ingested in undiluted form—even small volumes (as little as 3–5 mL) can cause CNS depression, seizures, and respiratory distress in adults, and the oil is contraindicated in children under 2 years and should be used with extreme caution in young children. Potential drug interactions include additive CNS-depressant effects with sedatives, theoretical interference with cytochrome P450 enzyme [metabolism](/ingredients/condition/weight-management) (CYP1A2, CYP2C9) by flavonoid components, and reduced absorption of orally co-administered iron supplements; use during pregnancy and lactation is not recommended due to absence of safety data.

## Scientific Research

The current evidence base for Eucalyptus camaldulensis consists entirely of in vitro and phytochemical characterization studies; no peer-reviewed randomized controlled trials or prospective human clinical studies have been published for this specific species. In vitro [antioxidant](/ingredients/condition/antioxidant) assays using DPPH, ABTS, FRAP, and superoxide protocols consistently demonstrate dose-dependent activity across methanolic, acetone, and aqueous extracts at 100–500 µg/mL, with total polyphenols quantified at 364.1 ± 8.2 mg GAE/g providing a robust phytochemical foundation. [Antimicrobial](/ingredients/condition/immune-support) and cytotoxic data derive from agar diffusion, broth microdilution, and cell viability (MTT-type) assays showing 16–44% cytotoxic cell death at 20–120 µg/mL, but these concentrations have not been correlated with achievable human plasma levels. The species' traditional use in anti-tuberculosis Middle Eastern herbalism provides ethnopharmacological plausibility but remains unvalidated by clinical endpoint data, warranting well-designed human trials before therapeutic claims can be substantiated.

## Historical & Cultural Context

Eucalyptus camaldulensis was introduced to the Middle East and North Africa in the nineteenth century, initially for land drainage and timber, and was rapidly adopted into local herbalism as the climate proved ideal for its cultivation in Egypt, Iran, and the Levant. In Middle Eastern traditional medicine, the leaves have been employed as [antimicrobial](/ingredients/condition/immune-support) agents for respiratory diseases, including tuberculosis and bronchitis, with healers preparing steam inhalations and decoctions from freshly harvested or dried leaves. Australian Aboriginal peoples, within whose ancestral territories the species is native, historically used the kino resin for wound treatment and the leaves for respiratory ailments in traditional smoking ceremonies. The species' name references the Camaldoli garden near Naples, Italy, where specimens cultivated from Australian seed were first formally described by Dehnhardt in 1832, reflecting its early botanical documentation in the European tradition.

## Synergistic Combinations

Eucalyptus camaldulensis essential oil is traditionally combined with other [antimicrobial](/ingredients/condition/immune-support) botanicals such as thyme (Thymus vulgaris, rich in thymol and carvacrol) and tea tree oil (Melaleuca alternifolia), where additive to synergistic membrane-disruption and enzyme-inhibitory effects against respiratory pathogens are proposed based on in vitro checkerboard assay data for analogous eucalyptol-containing preparations. Pairing ellagitannin-rich leaf extracts with vitamin C (ascorbic acid) may enhance [antioxidant](/ingredients/condition/antioxidant) capacity through regeneration of oxidized polyphenol radicals back to their reduced, active forms, a mechanism documented for similar ellagitannin-ascorbate combinations. In traditional Middle Eastern practice, E. camaldulensis decoctions are sometimes combined with honey, whose own antimicrobial (methylglyoxal, hydrogen peroxide) and osmotic mechanisms may complement the cineole-driven and tannin-driven antibacterial actions of the leaf extract.

## Frequently Asked Questions

### What is eucalyptus camaldulensis used for medicinally?

Eucalyptus camaldulensis leaves and essential oil are used in Middle Eastern and North African herbalism primarily for respiratory infections, including tuberculosis and bronchitis, exploiting the membrane-disrupting antimicrobial activity of 1,8-cineole (up to 84.9% of the essential oil). The bark kino exudate, rich in kinotannic acid (45%) and total tannins (up to 76.7%), is applied topically as an astringent for wound healing. All current evidence is based on in vitro studies and traditional ethnobotanical records; no human clinical trials have confirmed these therapeutic applications.

### What is the main active compound in eucalyptus camaldulensis?

The primary bioactive compound is 1,8-cineole (eucalyptol), which constitutes an average of 77% and up to 84.9% of the leaf essential oil and is responsible for antimicrobial, mucolytic, and anti-inflammatory effects through membrane disruption and NF-κB pathway modulation. Equally important are the ellagitannins—tellimagrandin I, pedunculagin, vescalagin (5 mg/mL), and castalagin (4 mg/mL)—which provide antiviral, antibacterial, and antioxidant activity at low micromolar concentrations. The plant also concentrates flavonoid glucuronides including quercetin glucuronide (5.15%) and kaempferol glucuronide (3.36%).

### Is eucalyptus camaldulensis essential oil safe to ingest?

Undiluted eucalyptus essential oil high in 1,8-cineole is considered toxic when ingested; even small volumes (approximately 3–5 mL in adults) can cause CNS depression, seizures, vomiting, and respiratory distress. Oral ingestion is contraindicated in children under 2 years of age, and internal use in any age group should only occur under professional medical supervision using appropriately diluted and dose-controlled preparations. No standardized safe oral dose for E. camaldulensis preparations has been established in clinical trials.

### How does eucalyptus camaldulensis compare to eucalyptus globulus?

Both species are dominated by 1,8-cineole in their essential oils and share broad antimicrobial and respiratory pharmacology; however, E. globulus has been more extensively studied in clinical contexts, particularly for cineole-based pharmaceutical preparations for sinusitis and COPD, while E. camaldulensis has a substantially larger ellagitannin content that may confer superior antiviral and antioxidant activity at equivalent extract doses. E. camaldulensis essential oil can vary more widely in cineole content (13.73–84.9%) depending on provenance compared to the typically higher and more consistent cineole levels in E. globulus. Clinical evidence specifically for E. camaldulensis remains at the in vitro stage only.

### What is the antioxidant activity of eucalyptus camaldulensis leaf extract?

Methanolic and acetone extracts of E. camaldulensis leaves demonstrate strong in vitro antioxidant activity, achieving up to 90% DPPH radical inhibition at 500 µg/mL and 15–75% superoxide radical quenching at 100–500 µg/mL, attributed to a total polyphenol content of 364.1 ± 8.2 mg GAE/g and flavonoid content of 80.5 ± 0.9 mg QE/g dry extract. Ferric-reducing antioxidant power (FRAP) is dose-dependent across the tested concentration range. These values position the species among the higher-potency antioxidant eucalyptus species in comparative phytochemical surveys, though in vivo and clinical antioxidant efficacy remains undemonstrated.

### Is eucalyptus camaldulensis safe during pregnancy and breastfeeding?

Eucalyptus camaldulensis essential oil should be avoided during pregnancy and breastfeeding due to its potent 1,8-cineole content, which can cross biological barriers and may affect fetal development or nursing infants. While leaf extracts in traditional herbalism have a longer history of use, pregnant and nursing women should consult a healthcare provider before any internal use. External application of diluted essential oil should also be avoided during these periods.

### Does eucalyptus camaldulensis interact with tuberculosis medications or antibiotics?

While eucalyptus camaldulensis shows in vitro antimicrobial activity against tuberculosis pathogens, its use alongside prescription TB medications or antibiotics has not been thoroughly studied in clinical trials and may affect drug efficacy or increase side effects. Patients taking pharmaceutical antimicrobials should inform their healthcare provider before using eucalyptus camaldulensis supplements or essential oil products. The herb should not be used as a substitute for conventional medical treatment of tuberculosis or serious bacterial infections.

### What is the difference between eucalyptus camaldulensis leaf extract and essential oil for antimicrobial benefits?

Eucalyptus camaldulensis essential oil, concentrated in 1,8-cineole (typically 70–80%), delivers potent antimicrobial activity in smaller volumes and is more bioavailable for inhalation therapy, while standardized leaf extracts provide broader polyphenolic antioxidant compounds with potentially gentler systemic effects. Essential oil is more suitable for respiratory applications via diffusion or steam inhalation, whereas methanolic or acetone leaf extracts offer oral supplementation options with different absorption kinetics. The essential oil carries higher toxicity risk with ingestion, making leaf extracts the safer choice for internal use.

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