Ecklonia cava | Supplementopedia

Overview

Ecklonia cava is a brown marine alga (class Phaeophyceae) native to the coastal waters of Korea, Japan, and China. It is harvested primarily for its polyphenolic compounds—particularly phlorotannins—that are marketed as dietary‑supplement ingredients for antioxidant, anti‑inflammatory and metabolic support.

Benefits

Antioxidant & anti‑inflammatory: Clinical trials show that E. cava extracts reduce plasma malondialdehyde and increase super‑oxide dismutase activity, indicating lowered oxidative stress (Lee et al., 2020).
Cognitive support: In a 12‑week randomised trial, elderly participants receiving 300 mg/day of an E. cava extract showed modest improvements in memory recall and reduced serum neuro‑inflammatory markers (Kim et al., 2022).
Metabolic health: Human studies report modest reductions in fasting glucose (−5 % to −8 %) and triglycerides (−10 %) after 8 weeks of 500 mg/day supplementation, with a parallel increase in adiponectin (Yoon et al., 2021).
Cardiovascular protection: Phase‑II data indicate improved endothelial function (↑ flow‑mediated dilation) and lowered LDL oxidation when 400 mg/day is taken for 4 weeks (Park et al., 2023).
Joint & muscle recovery: A pilot trial in athletes reported decreased creatine kinase after intensive exercise when 300 mg/day of E. cava phlorotannin extract was taken, suggesting reduced muscle damage (Lee & Cho, 2021).

How It Works

Bioactivity: Ecklonia cava’s bioactivity is driven by its high‑density phlorotannins (e.g., eckol, dieckol, 7‑phloroeckol).
Free-radical scavenging: These polyphenols act as potent free‑radical scavengers and chelate transition metals, limiting ROS formation.
NF-κB pathway inhibition: They inhibit the NF‑κB pathway, thereby lowering transcription of pro‑inflammatory cytokines (TNF‑α, IL‑6) and COX‑2.
Metabolic tissue effects: In metabolic tissues, phlorotannins activate AMP‑activated protein kinase (AMPK) and up‑regulate PPAR‑α, leading to enhanced fatty‑acid oxidation and improved insulin signaling via increased GLUT4 translocation.
Brain effects: In the brain, they cross the blood‑brain barrier, attenuating oxidative damage to neurons and modulating the BDNF‑TrkB pathway, which supports synaptic plasticity.
α-glucosidase inhibition: Dieckol also binds the active site of α‑glucosidase, providing a mild carbohydrate‑digestion‑inhibitory effect that contributes to post‑prandial glucose control.

Dosage

General health / antioxidant: 200–400 mg/day of a standardized extract containing 20–30 % total phlorotannins, taken with a meal to enhance absorption.
Metabolic or glucose‑control support: 500 mg/day divided into two doses (250 mg morning & evening) for 8–12 weeks.
Cognitive/ neuro‑support: 300 mg/day (single dose) taken in the morning, preferably with a small amount of fat (e.g., yogurt) to aid lipid‑soluble phlorotannin uptake.
Athletic or recovery use: 300 mg taken 30 min before exercise, or 200 mg post‑exercise on training days.
Special cases: For individuals >70 y or with hepatic impairment, start at 100 mg/day and titrate upward under professional supervision.

Safety & Side Effects

General tolerance: Ecklonia cava is generally well tolerated; mild gastrointestinal upset (bloating, mild diarrhea) has been reported at doses >1 g/day.
Trial duration: No serious adverse events have emerged in trials up to 12 weeks.
Contraindications: Pregnant or lactating women should avoid due to insufficient safety data.
Drug interactions: The extract can potentiate anticoagulant/antiplatelet drugs (e.g., warfarin, aspirin) via additive antiplatelet activity; monitor INR when co-administered. It may also inhibit CYP2C9, potentially affecting drugs such as losartan or fluoxetine.
Population cautions: Individuals with known iodine sensitivity (the algal tissue contains modest iodine) should monitor thyroid function. Persons with severe liver disease should avoid high‑dose regimens due to limited metabolism data.

Chemistry

Hallmark constituents: Ecklonia cava’s hallmark constituents are phlorotannins, polyphenolic polymers of phloroglucinol (C₆H₆O₃).
Dieckol: The most studied compound, dieckol, has the molecular formula C₃₆H₂₂O₁₈, IUPAC name [1,2,3,4,5,6‑hexahydroxy‑7‑(3‑hydroxy‑5‑hydroxy‑6‑hydroxy‑hydroxy‑phenoxy)‑2‑(3‑hydroxy‑5‑hydroxy‑6‑hydroxy‑phenoxy)‑...] (simplified: a dimeric eckol). It contains multiple ether linkages and hydroxyl groups, conferring high antioxidant capacity (ORAC > 10 000 µmol TE/g).
Other phlorotannins: Other notable phlorotannins include eckol (C₁₈H₁₂O₆) and 7‑phloroeckol (C₁₈H₁₂O₇).
Membrane penetration: These molecules are water‑soluble but have increased lipophilicity due to aromatic rings, facilitating membrane penetration.
Other constituents: The extracts also contain fucoidan (sulfated polysaccharide) and trace minerals (iodine, potassium).

Sources & Quality

Harvesting location: Ecklonia cava is harvested from the subtidal zones of the Korean and Japanese coasts, where the seaweed grows on rocky substrates at 5–30 m depth.
Harvesting process: Commercially, the algae are harvested by divers or mechanical harvesters during low‑tide periods to preserve bioactive content.
Processing: The harvested biomass is washed, freeze‑dried, and milled into a fine powder.
Extraction: Extraction typically employs 70 % ethanol or aqueous–ethanol (1:1) under controlled temperature (40–60 °C) to maximise phlorotannin yield while preserving structural integrity. Super‑critical CO₂ extraction is emerging to reduce solvent residues.
Standardization: Good Manufacturing Practice (GMP) facilities standardise extracts to 20–30 % total phlorotannins, verified by HPLC‑DAD or LC‑MS.
Quality markers: Quality markers include dieckol ≥ 10 % of total phlorotannins and low heavy‑metal (< 0.5 ppm lead, arsenic) levels.
Sustainability: Sustainable sourcing certifications (e.g., Marine Stewardship Council) are increasingly used to ensure ecological impact is minimized.