Delphinidin-3-Glucoside — Myrtillin (Anthocyanin · Retinal Protection · Visual Acuity)

Compound	Delphinidin-3-Glucoside (Myrtillin)
Chemical class	Polyphenol — Anthocyanin (Delphinidin-3-O-β-D-Glucoside)
CAS	6906-38-3
Primary source	Vaccinium myrtillus (bilberry), V. corymbosum (blueberry), Ribes nigrum (black currant)
Key applications	Retinal protection, visual acuity, eye health, AREDS-relevant
Claim strength	Moderate
Typical form	Bilberry extract standardised to total anthocyanins; myrtillin isolate
Buy from Herbuno	Bilberry Extract Powder → Bilberry Fruit Oil Soluble Extract - Vaccinium myrtillus →

Name origin: Myrtillin — from Vaccinium myrtillus (bilberry / European blueberry) — the plant in which delphinidin-3-glucoside was first characterised and most extensively studied. It is the principal anthocyanin in bilberry alongside delphinidin-3-galactoside, delphinidin-3-arabinoside, and cyanidin glycosides. Traditional use: Bilberry (Vaccinium myrtillus) has been used in European folk medicine since medieval times for eye complaints, diarrhoea, and urinary tract conditions. Bilberry leaf preparations were used for blood glucose management in European phytomedicine long before modern research identified the anthocyanin fraction as the primary bioactive. Research trajectory: Delphinidin-3-glucoside has the most direct evidence for retinal photoprotection and visual function support among individual anthocyanins, attributable to its high antioxidant capacity and documented rhodopsin regeneration activity. Bilberry extract (myrtillin-standardised) has been studied in multiple human eye health trials. Commercial source: Commercially available via bilberry extract standardised to total anthocyanins. See sourcing options below.

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Evidence for Delphinidin-3-Glucoside Applications

Retinal protection and visual function: Delphinidin-3-glucoside (myrtillin) protects retinal pigment epithelial (RPE) cells from oxidative damage in cell models — a mechanism directly relevant to age-related macular degeneration (AMD) pathology. Bilberry extract RCTs show improvements in visual acuity, contrast sensitivity, and dark adaptation in subjects with normal-tension glaucoma, myopia, and retinal stress. Myrtillin is proposed as the key contributor to bilberry’s visual benefits alongside other delphinidin glycosides. Claim strength: Moderate.

Rhodopsin regeneration: Delphinidin-3-glucoside accelerates rhodopsin (visual purple) regeneration in retinal rod cells in vitro — the mechanism underlying visual dark adaptation. This has been proposed as the basis for traditional bilberry use in night vision support, though controlled human trials have not consistently demonstrated improved night vision in healthy subjects. Claim strength: Moderate (mechanism established; human dark adaptation data mixed).

Antioxidant and anti-inflammatory (ocular): Myrtillin has high antioxidant capacity (trihydroxylated B-ring, catechol/pyrogallol) and reduces inflammatory cytokine production in ocular cell models. Relevant for dry eye, eye fatigue, and screen-exposure ocular stress formulations. Claim strength: Moderate.

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Dosage & Formulator Specification

Bilberry extract eye health studies: 160–480 mg/day standardised bilberry extract (25–36% total anthocyanins, equivalent to 40–170 mg total anthocyanins/day). The classic European bilberry extract dose is 160 mg/day at 25% anthocyanins (40 mg total anthocyanins). For modern premium eye health formulations, 200–300 mg/day at 36% anthocyanins is increasingly standard.

Herbuno supplies Bilberry Extract Powder and Bilberry Fruit Oil Soluble Extract. For eye health oral applications, the water-soluble powder extract is appropriate. For topical or specialised lipid-based delivery, the oil-soluble extract provides compatibility with lipid matrices. Specify minimum 25% total anthocyanins (pH differential) with an individual anthocyanin HPLC profile confirming delphinidin-3-glucoside as the primary constituent.

Myrtillin is the most extensively pharmacokinetically characterised bilberry anthocyanin. After oral dosing of bilberry extract, delphinidin-3-glucoside reaches plasma within 30–60 minutes, with peak concentration at 1.5–2 hours. It is detected in ocular tissues (retina and choroid) in animal pharmacokinetic studies — supporting mechanistic plausibility for retinal applications. Standard anthocyanin pH stability considerations apply.

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Frequently Asked Questions — Delphinidin-3-Glucoside

Is bilberry extract AREDS-relevant for age-related macular degeneration?
The AREDS (Age-Related Eye Disease Study) formula uses vitamins C and E, beta-carotene (or lutein/zeaxanthin in AREDS2), zinc, and copper. Bilberry anthocyanins are not in the AREDS formula and do not have the same level of RCT evidence for AMD prevention or progression. However, bilberry extract addressing oxidative stress in retinal RPE cells is mechanistically complementary to AREDS nutrients, and it is commonly co-formulated with lutein/zeaxanthin in comprehensive eye health supplements without direct AREDS equivalence claims.

Why is bilberry (European) considered superior to North American blueberry for eye health?
Wild bilberry (Vaccinium myrtillus) has significantly higher total anthocyanin content per gram than cultivated highbush blueberry (V. corymbosum), and its anthocyanin profile is enriched in delphinidin glycosides. Bilberry is a smaller, wild berry consumed whole including the skin (where anthocyanins concentrate), while cultivated blueberries are larger with proportionally less skin relative to flesh. For standardised extract production, bilberry yields higher anthocyanin content per extraction unit.

Can delphinidin-3-glucoside penetrate to the retina after oral dosing?
Animal pharmacokinetic studies (rats) demonstrate intact delphinidin-3-glucoside in retinal tissue after oral bilberry extract dosing. Human ocular pharmacokinetic data are not available due to ethical constraints on retinal tissue sampling. The animal data provide mechanistic plausibility but not direct human confirmation. The consistent human clinical outcomes in bilberry eye health trials support the conclusion that sufficient anthocyanin reaches relevant ocular targets after oral dosing.

Is there a synergy between bilberry extract and lutein for eye health formulations?
Yes — bilberry anthocyanins (antioxidant, anti-inflammatory, rhodopsin regeneration) and lutein/zeaxanthin (macular pigment density, blue light filtration, RPE protection) address complementary mechanisms of retinal protection. Co-formulation is mechanistically rational and commercially well-established in premium eye health formulations. The combination provides broader ocular photoprotection than either ingredient alone.

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Claim-strength scale – High = multiple human RCTs; Moderate = limited trials or strong preclinical convergence; Emerging = early-stage lab or animal data.

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