European Elder (Sambucus nigra L.)
1. Identity
Botanical Classification and Nomenclature
European elder or elderberry (Sambucus nigra L., family Viburnaceae) is a plant species with known high pharmaceutical and nutritional value. Common English names include Elder, European black elder (for the tree) and Elderberry, Common elderberry, Black elderberry, and European elderberry (for the fruit). The scientific name Sambucus nigra L. is etymologically derived from the Greek sambuca, a musical instrument similar to a harp that Romans reportedly fashioned from the wood of this tree. The Latin specific epithet nigra means "black," referring to the deeply dark colour of the berries. The English term "elder" is not believed to come from the word "old," but from the Anglo-Saxon æld, meaning fire, because the hollow stems of the branches were used as bellows to blow air into a fire.
There are several closely related species, native to Asia and North America, which are similar and sometimes treated as subspecies of Sambucus nigra, including S. nigra subsp. canadensis and S. nigra subsp. cerulea. Richard Bolli's 1994 monograph "Revision of the Genus Sambucus" proposed the placement of five species as subspecies of Sambucus nigra, including S. canadensis (American elderberry) as S. nigra subsp. canadensis. The common or European elderberry is designated as S. nigra subsp. nigra, or simply S. nigra. These changes have been accepted by the Integrated Taxonomic Information System (ITIS), but not the World Flora Online (WFO) as of March 2026.
Natural Source and Distribution
Sambucus nigra L., commonly known as black elder, European elder, or elderberry, is native to the temperate regions of Europe, West Asia, and North Africa, though it has also been introduced to the Americas, South Asia, and Australia. It is a perennial deciduous shrub that can reach the height of a small tree, with large, dark-green pinnate leaves and small, white–yellowish fragrant flowers arranged in corymb inflorescences that blossom through May to June. The fruits of black elder are small, spherical drupes that ripen during August and September in temperate regions. Depending on the maturity stage, their colour ranges from green (for unripe fruits) to shiny black–violet (for fully ripe ones).
Most of the botany, plant morphology, and fruit development are very similar between S. nigra and S. canadensis; however, American elderberry tends to spread more aggressively by underground rhizomes and is usually multi-trunked. European elderberry, on the other hand, is a single-trunked or few-trunked large shrub or small tree.
Plant Parts Used and Common Preparations
All parts of the tree have long been used in traditional medicine — the bark, the leaves, the flowers, and the fruit. In contemporary commerce, the fruit (berry) and flower are the principal parts used, the bark and leaves having largely been abandoned owing to toxicity concerns (see Safety section). Both the flowers and the berries have a long tradition of culinary use, primarily for cordial and wine. Modern dosage forms include syrups, liquid extracts, tinctures, lozenges, capsules, tablets, gummies, dried berry powder, and standardised extracts. Black elder is used as an antiviral, especially to treat common cold and flu. The flower of black elder has been approved by the German Commission E and ESCOP for its mentioned usage, and its qualification parameters were described in several pharmacopoeias. However, the fruits, with similar uses as the flowers, have not been considered by the pharmacopoeias, even though the number of black elder fruit supplements marketed under different brands is increasing steadily.
2. Traditional and Historical Use
Ancient Greece and Rome
Greek physicians, including Hippocrates (460–370 BCE), often referred to elderberry as their "medicine chest" due to its versatility. The Roman naturalist Pliny the Elder (23–79 CE) documented its use for skin conditions, inflammation, and respiratory ailments. Both Greek and Roman herbalists recommended elderberry extracts as a general tonic.
Celtic, Germanic, and Northern European Traditions
Among Celtic and Germanic tribes, elder trees were believed to have protective and magical properties. The plant was commonly used in sacred rituals, and elderberry infusions were believed to ward off evil spirits and disease. The berries were sometimes fermented into medicinal wines, and the bark was used in poultices for external healing. Black elder has been cultivated in Sweden at least since the Middle Ages. Previously, this plant was associated with a supernatural being to whom sacrifices were made, and its fruits were used in folk medicine and its wood for fuel and crafts.
Elderberry is one of the trees with the most magical potential in European culture. According to Christian tradition, it has historically been considered as the emblem of grief and death. In the Teutonic tradition it was related to the nymph of the Hyldemoer forests, who was believed to live in its branches and pursue those who cut it down.
Ethnomedicinal Preparations and Purposes
For centuries, Sambucus nigra has been a staple in traditional medicine across Europe, Asia, and North Africa. Many cultures recognised its healing properties and used different parts of the plant—flowers, berries, leaves, and bark—for various ailments. Extended ethnopharmacological research in the area of Drama, Greece, documented the traditional uses of black elder in the folk medicine practiced for centuries in that area; elders used plant parts prepared as a remedy tea to cure tuberculosis, influenza, and cough with phlegm.
Berries were used as a laxative and diuretic, particularly in decoctions for constipation and to promote urinary flow, reflecting its role as a versatile remedy in folk practices across Europe since antiquity. In Europe, tea made from flowers of the elderberry subspecies nigra is a popular herbal treatment for respiratory infections such as colds and influenza.
3. Key Constituents and Active Compounds
Fruit (Berry) Constituents
Analysis of elderberry showed that it contains high biological activity components, primarily polyphenols, mostly anthocyanins, flavonols, phenolic acids and proanthocyanidins, as well as terpenes and lectins.
Anthocyanins
Compared with other fruit, elderberry is a very rich source of anthocyanins (approximately 80% of the polyphenol content). The antioxidative properties of elderberries are mostly determined by anthocyanins, which are a large group of bioactive compounds (cyanidin-3-glucoside: 65.7% of all anthocyanins), as well as flavonoids, flavonols, and phenolic acids. The fruit of Sambucus nigra contains anthocyanins, especially cyanidin-3-glucoside and cyanidin-3-sambubioside. Two other (minor) anthocyanins are cyanidin-3,5-diglucoside, and cyanidin-3-sambubioside-5-glucoside. In addition, trace quantities of cyanidin-3-rutinoside, pelargonidin-3-glucoside, and delphinidin-3-rutinoside have been identified in certain elderberry cultivars.
Phenolic Acids and Flavonols
The main polyphenols in elderberry fruit are chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, quercetin, quercetin-3-rutinoside (rutin), quercetin-3-glucoside (isoquercitrin), kaempferol-3-rutinoside, kaempferol-3-glucoside (astragalin), isorhamnetin-3-rutinoside, and isorhamnetin-3-glucoside. The primary flavonol is rutin, while the other flavonols, isoquercitrin and astragalin, occur in elderberries in smaller amounts.
Other Constituents
Elderberry plant (Sambucus nigra) is a good source of protein, free and conjugated forms of amino acids, unsaturated fatty acids, fibre fractions, vitamins, antioxidants, and minerals. The phytotherapeutic principles found in elderberry fruits give them antiviral, antibacterial, and antidiabetic properties, antitumor potential, antioxidant, antidepressant, and immune-boosting properties, as well as certain impacts on obesity and metabolic dysfunctions.
Flower Constituents
Key constituents found in elderflower (Sambucus nigra) include flavonoids (isoquercitrin, hyperoside, rutin), phenolic acids (chlorogenic acid), triterpenes (ursolic and oleanolic acids), and a small quantity of essential oil. The British Pharmacopoeia requires not less than 0.8% flavonoids expressed as isoquercitroside. The primary polyphenol constituents in the flower extract are flavonoids and phenolic acids, while anthocyanins are the main components in the fruit extract.
Cyanogenic Glycosides (Toxic Constituents)
Elderberry leaves have been proved to contain cyanogenic glycosides such as zierin, sambunigrin, prunasin, and holocalin. The highest amounts of sambunigrin are present in elder leaves (27.68–209.61 µg/g FW), lower amounts were found in flowers (1.23–18.88 µg/g FW), whereas berries contain the lowest amounts of this compound (0.08–0.77 µg/g FW). These compounds occur primarily in unripe berries and are degraded during heat treatment.
4. Mechanisms of Action
Antioxidant Activity
Elderberry is a very rich source of anthocyanins (approximately 80% of the polyphenol content). These polyphenols essentially contribute to the high antioxidant and anti-inflammatory capacities and the health benefits of elderberry fruit extract. Bioactive compounds in elderberry can also increase the activity of enzymes in the small intestine, liver, and lungs, including peroxidase, S-transferase, glutathione reductase, and catalase.
Anti-inflammatory Pathways
Health benefits of S. nigra primarily stem from flavonoid-mediated modulation of NF-κB and PPARγ pathways, demonstrating dose-dependent antioxidant and anti-inflammatory activities. Polyphenols have shown an ability to suppress prostaglandin pathways. Flavones effectively reduce the synthesis of cyclooxygenase-2 (COX-2), whereas flavonoids can inhibit eicosanoids such as prostaglandins, decreasing inflammation and pain.
Antiviral Mechanisms
Anthocyanins can attach to (and render ineffective) viral glycoproteins that enable viruses to enter host cells, thereby potentially having an inhibitory effect on viral infection. It has been proposed that elderberries could prevent influenza infection by competitively inhibiting the binding of the influenza virus to host cells during pathogenesis. Extracts of elderberry have demonstrated in vitro inhibitory effects on influenza A and influenza B viruses, as well as H1N1 "swine" flu virus.
In addition to this direct action on viruses, elderberry may have an effect on the immune system through cytokines. There is some evidence that elderberry increases the production of inflammatory cytokines (i.e., TNF-alpha, interleukins), although there is also evidence suggesting that cytokine production is decreased.
Immunomodulatory Effects
The flavonoids, phenolic acids, and immunomodulatory polysaccharides identified from elderberries may contribute to their antiviral activity, but the mechanisms for this type of activity have not been investigated in detail. Black elderberry can prevent oxidative stress and reduce blood pressure and prevent cardiovascular diseases, diabetes mellitus, and neurodegenerative diseases thanks to the polyphenols it contains. It can prevent diseases, stimulate the immune system, show an antitumor effect, and be effective in disease processes by raising the activity of antioxidant enzymes, including glutathione.
5. Scientific Evidence by Area of Use
5.1 Upper Respiratory Infections: Common Cold and Influenza
This is the area of elderberry research with the strongest and most clinically relevant human evidence, though the total body of evidence remains limited in scale.
Key Randomized Controlled Trials (RCTs)
Two previous studies, in 27 and 60 patients respectively, found that elderberry extract supplements shortened the duration of proven influenza by approximately 4 days compared with placebo (p < 0.001 in both studies).
A randomized, double-blind, placebo-controlled clinical trial of 312 economy-class passengers travelling from Australia to an overseas destination aimed to investigate whether a standardised membrane-filtered elderberry (Sambucus nigra L.) extract has beneficial effects on physical, especially respiratory, and mental health. Most cold episodes occurred in the placebo group (17 vs. 12); however, the difference was not significant (p = 0.4). Placebo group participants had a significantly longer duration of cold episode days (117 vs. 57 days, p = 0.02).
The elderberry extract-treated group saw a substantial improvement in symptoms, including fever, in 93.3% of cases within 2 days, whereas the control group saw an improvement in 91.7% of patients within 6 days (p = 0.001).
Meta-Analyses
A 2019 meta-analysis provides evidence that elderberry supplementation at the onset of upper respiratory symptoms substantially reduces overall symptom duration as compared to a control group, with an effect size of 1.717. This analysis included 89 participants in the elderberry group and 91 participants in the control group for a total of 180 participants.
Systematic Reviews
Wieland et al. (2021) aimed to determine benefits and harms of elderberry for the prevention and treatment of viral respiratory infections, and to assess the relationship between elderberry supplements and negative health impacts associated with overproduction of pro-inflammatory cytokines. The authors conducted a systematic review and searched six databases, four research registers, and two preprint sites. Two reviewers independently assessed studies for inclusion and assessed risk of bias using Cochrane tools. The overall time to resolution or global improvement of illness was nearly three days shorter in the elderberry group compared to the placebo group (MD −2.68 days, 95% CI −5.23 to −0.13; 2 studies, 87 participants). The review concluded that elderberry may be a safe option for treating viral respiratory illness, and there is no evidence that it overstimulates the immune system. However, the evidence on both benefits and harms is uncertain, and information from recent and ongoing studies is necessary to make firm conclusions.
Evidence Summary
Black elderberry was associated with clinically meaningful reductions in symptom severity and illness duration, although evidence for its preventive efficacy remains limited. Overall, the clinical evidence in this area is positive but constrained by small sample sizes, heterogeneity of preparations, and limited high-quality trials; larger, well-powered RCTs are needed before definitive conclusions can be drawn.
5.2 Cardiovascular Health
The antioxidant and protective potential of elderberry preparations has been established in cardiovascular diseases. Proposed health effects include attenuation of cardiovascular disorders. However, direct large-scale human clinical trial data specifically on cardiovascular endpoints (e.g., blood pressure, lipid profiles, cardiac events) from interventional studies in humans remain limited and preliminary. The available evidence is primarily derived from in vitro and animal studies demonstrating antioxidant capacity, with mechanistic plausibility supported by the flavonoid content of the plant.
5.3 Diabetes and Metabolic Function
Black elderberry (Sambucus nigra L.) flowers are rich in polyphenolic compounds, including chlorogenic acid and quercetin derivatives, which are known for their health benefits, particularly their antioxidant and antidiabetic properties. Research has aimed to optimize extraction conditions and evaluate their potential for antidiabetic action. Results indicated that the Black Beauty, Obelisk, and Haschberg cultivars demonstrated significant inhibition of α-glucosidase, with a high inhibitory potential against α-amylase enzymes for the Obelisk cultivar. This inhibition of carbohydrate-digesting enzymes is mechanistically relevant to blood glucose management, but to date this evidence is from in vitro and preclinical models. Human clinical trial data on glycaemic outcomes from elderberry supplementation specifically are limited.
5.4 Antioxidant and Anti-inflammatory Effects
The presence of biologically active substances with antioxidant properties in the flowers and fruits of S. nigra L., mainly polyphenols and anthocyanins, determines their health-promoting properties, including anti-inflammatory and anticancer properties. Sambucus nigra fruit extract revealed pronounced and dose-dependent in vivo anti-inflammatory activity, assessed by the cotton pellet-induced granuloma test. Most anti-inflammatory evidence is from animal and in vitro experiments; robust human clinical data on inflammatory biomarkers as primary outcomes are scarce.
5.5 Antimicrobial Activity
The most sensitive microorganism to the antimicrobial activity of elderberry extract was proven to be Staphylococcus aureus, and Pseudomonas aeruginosa had the lowest minimum inhibitory concentration of 1.95 mg/mL. This antimicrobial evidence is in vitro only; there are no published clinical trials examining elderberry as a direct antibacterial treatment in humans.
5.6 Anticancer Properties
Elderberry exhibits preventive and supportive anticancer effects through antioxidant, antiproliferative, and pro-apoptotic mechanisms. Its phytochemicals may reduce chemotherapy-related toxicity and enhance tumour cell sensitivity to treatment. However, heterogeneity in extract preparation, dosage, and experimental design, combined with limited human clinical evidence, restricts firm nutritional or therapeutic conclusions. Current evidence on S. nigra's anticancer effects is predominantly preclinical, with limited in vivo and no clinical trial data.
5.7 Cytokine Modulation and Immune Overstimulation Concerns
Part of elderberry's activity involves increasing cytokine production at the first stage of viral attachment and early viral replication, which helps kill the virus and stop replication. Once the cytokine storm begins, it would theoretically no longer be appropriate, but there is no data either way. During the COVID-19 pandemic, there has been interest in elderberry supplements to treat or prevent illness, but also concern that elderberry might overstimulate the immune system and increase the risk of "cytokine storm." One small study compared elderberry to diclofenac (a nonsteroidal anti-inflammatory drug) and provided some evidence that elderberry is as effective or less effective than diclofenac in cytokine reduction over time.
6. Body Systems and Health Areas
- Respiratory system: Elderberry is used in the treatment of viral infections and upper respiratory infections, colds, flu, and catarrh.
- Immune system: Elderberry's anthocyanins demonstrate significant potential for immune support.
- Cardiovascular system: Elderberry extract has demonstrated beneficial effects related to cardiovascular diseases.
- Metabolic/endocrine: Elderberry has been noted for anti-diabetic properties and anti-inflammatory effects.
- Renal/urinary system: Elderberry has traditionally been used as a diuretic.
- Neurological system: Proposed health effects include attenuation of neurodegenerative disorders.
- Gastrointestinal system: Berries have historically been used as a mild laxative in traditional European practice.
- Oncology (preclinical only): Elderberry exhibits preventive and supportive anticancer effects through antioxidant, antiproliferative, and pro-apoptotic mechanisms.
7. Dosage Forms and Reported Dosages
Dried elderberry fruits are used as well as fresh fruit. The dried fruits and fresh fruit of elderberry in various herbal preparations were considered for inclusion during the assessment work in support of the establishment of a draft Community herbal monograph by the EMA.
The following dosages were reported in the clinical and review literature cited above:
- Two randomized, double-blind, placebo-controlled trials, in 27 and 60 patients respectively, demonstrated shortening of the duration of proven influenza by approximately 4 days with elderberry extract supplementation versus placebo (p < 0.001 in both studies). These trials used a liquid elderberry extract (Sambucol®).
- By 48 hours of supplementation in one trial of 64 patients with flu-like symptoms, 9 patients (28%) in the elderberry extract-supplemented group were void of all symptoms, 19 patients (60%) showed complete relief from some symptoms. No patient in the placebo group achieved complete recovery, and only 5 patients (16%) showed improvement. Most patients in the placebo group remained the same or worsened over the 48-hour monitoring period.
- A fourth study of elderberry extract evaluated supplementation before, during, and after air travel in 312 passengers. More cold episodes occurred in the placebo group (17 vs. 12) but that did not reach statistical significance (p = 0.4). Placebo group participants had a significantly longer duration of cold episode days (117 vs. 57, p = 0.02) and the average symptom score over these days was also significantly higher (583 vs. 247, p = 0.05).
8. Safety Considerations and Interactions
Cyanogenic Glycosides: Raw and Unripe Plant Parts
Cyanogenic glycosides can be found in edible parts of some plants. When such plant parts are consumed, β-glucosidase present in the gut comes in contact with glycosides and cyanogenic glycosides hydrolyze to produce hydrogen cyanide (HCN), which is toxic. The unripe berries contain toxic constituents such as cyanogenic glycosides and should be avoided in elderberry preparation.
The cyanogenic glycosides zierin and holocalin are potentially toxic and life-threatening, because they can be hydrolysed resulting in the release of cyanide. However, they occur primarily in unripe berries and are degraded during heat treatment.
Results of analytical studies showed no quantifiable trace of cyanogenic glycosides (CNGs) in commercial elderberry juice. Levels of CNGs found in various fruit tissues of elderberry cultivars studied ranged from 0.12 to 6.38 µg/g. In pressed juice samples, the concentration range measured was 0.29–2.36 µg/mL, and in seeds the levels were 0.12–2.38 µg/g. Total cyanogenic potential was highest in the stems and green berries. Concentration levels in all tissues were generally low and at a level that poses no threat to consumers of fresh and processed elderberry products.
Processing and Preparation Effects
Elderberry fruit and its food products are not only a rich source of phenolics, boosting antioxidant activity, but also contain harmful cyanogenic glycosides. Processing considerably affects the content of elderberry phenolics and cyanogenic glycosides. Ingestion of elderberry parts in larger doses may cause gastrointestinal disorders, such as nausea, vomiting, weakness, and dizziness.
Gastrointestinal Adverse Effects
While elderberry is generally recognised as safe when properly prepared, clinical trials on long-term safety are limited. Safety data from short-term studies of processed, standardised extracts show mostly mild gastrointestinal adverse effects.
Drug Interactions: CYP450 Enzymes
Sambucus nigra did not show an inhibitory effect on CYP3A4 in vitro. This finding suggests a low likelihood of CYP3A4-mediated drug interactions, though in vitro data may not fully predict in vivo behaviour.
Immune Modulation: Theoretical Concerns
In some cases of COVID-19, proinflammatory cytokines are overproduced and the patient experiences what has been called a "cytokine storm," which increases risk of multiorgan failure and death. There is therefore concern that the potential benefits of elderberry in inhibiting viral replication may be negated by potential harms from cytokine release and immune system hyperresponsiveness. The Wieland et al. (2021) systematic review concluded that elderberry may be a safe option for treating viral respiratory illness and there is no evidence that it overstimulates the immune system. However, the evidence on both benefits and harms is uncertain and information from recent and ongoing studies is necessary to make firm conclusions.
Altitude and Variability of Toxic Compounds
The highest amounts of sambunigrin are present in elder leaves, lower amounts in flowers, and berries contain the lowest amounts of this compound. The content of sambunigrin in elderberry changes depending on the growing altitude.
Pharmacopoeia and Regulatory Context
Black elder is used as an antiviral, especially to treat common cold and flu. The flower of black elder has been approved by the German Commission E and ESCOP for its mentioned usage, and several pharmacopoeias have described its qualification parameters. The EMA has published a formal assessment report on Sambucus nigra fructus. Sales of elderberry supplements reached $320 million in the year 2020, according to an American Botanical Council (ABC) report, attributable to purported immune-enhancing effects of elderberry.
References
- Sambucus nigra L. (fam. Viburnaceae) in Sicily: Distribution, Ecology, Traditional Use and Therapeutic Properties — PMC
- Wild-Growing and Conventionally or Organically Cultivated Sambucus nigra Germplasm: Fruit Phytochemical Profile — PMC
- Health-Promoting Properties: Anti-Inflammatory and Anticancer Properties of Sambucus nigra L. Flowers and Fruits — PMC
- Bioactive properties of Sambucus nigra L. as a functional ingredient for food and pharmaceutical industry — PMC
- Sambucus Nigra Extracts – Natural Antioxidants and Antimicrobial Compounds — PMC
- Bioactive Potential of Elderberry (Sambucus nigra L.): Antioxidant, Antimicrobial Activity, Bioaccessibility and Prebiotic Potential — PMC
- In Vivo Anti-Inflammatory and Antinociceptive Activities of Black Elder (Sambucus nigra L.) Fruit and Flower Extracts — PMC
- Development of Potential Therapeutic Agents from Black Elderberries (the Fruits of Sambucus nigra L.) — PMC
- Elderberry Extracts: Characterization of the Polyphenolic Chemical Composition, Quality Consistency, Safety, Adulteration, and Attenuation of Oxidative Stress- and Inflammation-Induced Health Disorders — PMC
- Elderberries — A Source of Bioactive Compounds with Antiviral Action — PMC
- Black elderberry (Sambucus nigra) supplementation effectively treats upper respiratory symptoms: A meta-analysis of randomized, controlled clinical trials — PubMed
- Elderberry Supplementation Reduces Cold Duration and Symptoms in Air-Travellers: A Randomized, Double-Blind Placebo-Controlled Clinical Trial — PMC
- Elderberry Extract Outpatient Influenza Treatment for Emergency Room Patients Ages 5 and Above: a Randomized, Double-Blind, Placebo-Controlled Trial — PMC
- Elderberry for prevention and treatment of viral respiratory illnesses: a systematic review (Wieland et al., 2021) — PMC
- The Pros and Cons of Using Elderberry (Sambucus nigra) for Prevention and Treatment of COVID-19 — PMC
- Cyanogenic Glycoside Analysis in American Elderberry — PMC
- Final Assessment Report on Sambucus nigra L., fructus — European Medicines Agency (EMA)
- Advanced research on the antioxidant and health benefit of elderberry (Sambucus nigra) in food — a review — ScienceDirect
- Processed elderberry (Sambucus nigra L.) products: A beneficial or harmful food alternative? — ScienceDirect
- Health-promoting mechanisms and food applications of Sambucus nigra L.: A comprehensive review — ScienceDirect
- Flower and Leaf Extracts of Sambucus nigra L.: Application of Membrane Processes to Obtain Fractions with Antioxidant and Antityrosinase Properties — PMC
- Antidiabetic Potential of Black Elderberry Cultivars Flower Extracts: Phytochemical Profile and Enzyme Inhibition — PMC
- Are the Effects of Bioactive Components on Human Health a Myth?: Black Elderberry (Sambucus nigra L.) from Exotic Fruits — PubMed
- From Supernatural to Ornamental: Black Elder (Sambucus nigra L., Family Adoxaceae) in Sweden — MDPI Plants
- Sambucus nigra — Wikipedia
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