# Rubus ursinus (Pacific Blackberry)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/rubus-ursinus
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-31
**Evidence Score:** 2 / 10
**Category:** Herb
**Also Known As:** Pacific blackberry, California blackberry, Pacific dewberry, Trailing blackberry, Western trailing blackberry, California dewberry, Pacific coast blackberry

## Overview

Rubus ursinus, the Pacific blackberry, is a wild-harvested fruit rich in anthocyanins and ellagic acid that exert antioxidant effects by scavenging [reactive oxygen species](/ingredients/condition/antioxidant) and inhibiting lipid peroxidation. Chlorogenic acid concentrations up to 7.80 mg/100g further contribute to its phenolic profile, which supports cellular defense against oxidative stress.

## Health Benefits

• High [antioxidant](/ingredients/condition/antioxidant) content from phenolic compounds including chlorogenic acid (up to 7.80 mg/100g) and anthocyanins - evidence quality: compositional analysis only
• Vitamin C content (22.66-54.46 mg/100g) supporting [immune function](/ingredients/condition/immune-support) - evidence quality: compositional data only
• Rich in ellagic acid derivatives potentially supporting cellular health - evidence quality: chemical analysis only
• Contains epicatechin and quercetin derivatives with potential [cardiovascular](/ingredients/condition/heart-health) benefits - evidence quality: compositional studies only
• Natural source of organic acids including malic acid (up to 15.68 mg/100g) - evidence quality: biochemical analysis only

## Mechanism of Action

Anthocyanins in Rubus ursinus donate electrons to neutralize [free radical](/ingredients/condition/antioxidant)s and inhibit pro-oxidant enzymes such as xanthine oxidase, reducing superoxide anion generation. Ellagic acid acts as a potent inhibitor of [NF-κB](/ingredients/condition/inflammation) signaling and binds directly to DNA to block carcinogen-induced adduct formation. Chlorogenic acid modulates glucose-6-phosphatase activity and inhibits NADPH oxidase, contributing to both antioxidant and potential glucose-regulatory effects.

## Clinical Summary

No dedicated clinical trials have been conducted specifically on Rubus ursinus fruit in human subjects, making direct efficacy claims premature. Available evidence is limited to compositional analyses confirming phenolic content, including chlorogenic acid up to 7.80 mg/100g and vitamin C ranging from 22.66 to 54.46 mg/100g. Research on related Rubus species such as R. idaeus and R. fruticosus in small human studies (typically n=20–40) suggests anthocyanin-rich blackberries can modestly reduce [oxidative stress](/ingredients/condition/antioxidant) biomarkers like malondialdehyde, but these findings cannot be directly extrapolated to R. ursinus. The overall evidence base remains at the compositional and preclinical level, requiring species-specific human trials before therapeutic claims are supported.

## Nutritional Profile

Rubus ursinus (Pacific Blackberry) shares close nutritional similarity with cultivated blackberries (Rubus fruticosus) but with notable phytochemical distinctions as a wild species. Macronutrients per 100g fresh weight: carbohydrates approximately 9-10g (primarily glucose and fructose), dietary fiber 5.3g (mix of soluble pectin and insoluble cellulose/hemicellulose), protein 1.4g, fat 0.5g (including omega-6 linoleic acid), water content approximately 85-88g. Caloric density estimated 40-50 kcal/100g. Micronutrients: Vitamin C documented at 22.66-54.46 mg/100g (range reflecting ripeness and habitat variation; bioavailability moderate, subject to oxidative degradation post-harvest), Vitamin K1 approximately 19-20 mcg/100g, folate approximately 25 mcg/100g, manganese approximately 0.6-0.9 mg/100g (notably high relative to fruit category), potassium approximately 160-180 mg/100g, magnesium approximately 20mg/100g, calcium approximately 29mg/100g, iron approximately 0.6mg/100g (non-heme; bioavailability enhanced by co-present Vitamin C). Bioactive compounds: total phenolics estimated 200-400 mg GAE/100g fresh weight in wild specimens; chlorogenic acid documented up to 7.80 mg/100g; ellagic acid and ellagitannins (including sanguiin H-6 and lambertianin C) present at compositionally significant levels though precise concentrations specific to R. ursinus require further quantification beyond cultivar extrapolation; anthocyanins (cyanidin-3-glucoside, cyanidin-3-rutinoside predominant) contributing deep pigmentation with estimated 80-150 mg/100g in fully ripe fruit; quercetin and kaempferol glycosides present in smaller quantities. Dietary fiber fractions support gut microbiota fermentation producing short-chain fatty acids. Bioavailability note: polyphenol absorption is variable (5-20% for anthocyanins); food matrix fiber may slow glucose absorption, supporting low glycemic impact. Data gaps exist for precise mineral selenium content and complete tocopherol profile specific to wild R. ursinus populations.

## Dosage & Preparation

No clinically studied dosage ranges for Rubus ursinus extracts, powders, or standardized forms have been established due to absence of human trials. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Rubus ursinus fruit consumed as a whole food is generally regarded as safe for most adults, with no documented serious adverse effects at typical dietary intake levels. The high tannin and ellagic acid content may cause mild gastrointestinal discomfort, including nausea or loose stools, in sensitive individuals consuming large quantities. Chlorogenic acid may have additive effects with antidiabetic medications such as metformin by influencing glucose absorption, warranting caution in individuals managing [blood glucose](/ingredients/condition/weight-management) pharmacologically. Pregnancy safety at supplemental doses has not been formally studied; while culinary consumption is considered acceptable, concentrated extracts should be avoided during pregnancy and lactation until more data are available.

## Scientific Research

No human clinical trials, RCTs, or meta-analyses specifically on Rubus ursinus were identified. Research is limited to biochemical and compositional analyses of the fruit, with no PubMed PMIDs available for human studies on this specific species.

## Historical & Cultural Context

No documented traditional medicinal uses for Rubus ursinus were found in the available sources. The species is primarily noted as a wild edible fruit and, in some contexts, as an invasive plant.

## Synergistic Combinations

Vitamin C, anthocyanin complex, ellagic acid, quercetin, green tea extract

## Frequently Asked Questions

### How much vitamin C is in Pacific blackberries?

Rubus ursinus fruits contain between 22.66 and 54.46 mg of vitamin C per 100g of fresh weight, depending on ripeness and growing conditions. This range represents a meaningful contribution toward the adult recommended daily intake of 65–90 mg, though values vary considerably across wild-harvested populations.

### What antioxidants are in Pacific blackberries?

Rubus ursinus contains several phenolic antioxidants, most notably anthocyanins (responsible for the deep purple-black color), ellagic acid, and chlorogenic acid at concentrations up to 7.80 mg/100g. These compounds collectively inhibit lipid peroxidation and scavenge reactive oxygen species through both direct radical neutralization and enzyme-mediated pathways.

### Is Pacific blackberry the same as regular blackberry?

Rubus ursinus is a distinct species native to the Pacific Coast of North America and is considered the only true native blackberry of that region, differing genetically and morphologically from the European R. fruticosus aggregate or the introduced Himalayan blackberry (R. armeniacus). While its phytochemical profile is broadly similar to other Rubus species, specific compound concentrations and bioavailability data have not been extensively cross-compared in controlled studies.

### What is ellagic acid and why is it important in Pacific blackberries?

Ellagic acid is a polyphenolic compound found in Rubus ursinus that has been studied in laboratory and animal models for its ability to inhibit NF-κB activation, induce apoptosis in abnormal cells, and block carcinogen-DNA adduct formation. It is also a precursor to urolithins, metabolites produced by gut microbiota that demonstrate anti-inflammatory activity, though individual conversion capacity varies significantly based on gut microbiome composition.

### Are there any drug interactions with Pacific blackberry supplements?

Chlorogenic acid present in Rubus ursinus may potentiate the glucose-lowering effects of antidiabetic drugs such as metformin or sulfonylureas by reducing intestinal glucose absorption via inhibition of glucose-6-phosphatase, potentially increasing hypoglycemia risk. The high vitamin C content could also interfere with certain laboratory tests including serum glucose and bilirubin assays at high supplemental doses, and individuals on anticoagulant therapy should use caution as some Rubus phenolics exhibit mild antiplatelet properties in vitro.

### Can I get enough Pacific blackberry antioxidants from eating fresh berries instead of taking a supplement?

Fresh Pacific blackberries are an excellent natural source of antioxidants, containing significant levels of phenolic compounds and anthocyanins in their whole form. However, supplement extracts often concentrate these bioactive compounds to higher levels than would be practical to consume through diet alone, making supplementation useful for those seeking therapeutic doses. The choice depends on your dietary intake of fresh berries and your specific health goals, as food sources provide additional fiber and nutrients not isolated in extracts.

### Is Pacific blackberry safe for pregnant or nursing women?

While Pacific blackberries as a food are generally safe during pregnancy and nursing, the safety of concentrated supplements has not been extensively studied in these populations. Pregnant and nursing women should consult with their healthcare provider before taking Pacific blackberry supplements, as the concentrated phenolic compounds and their metabolic effects during these sensitive periods require professional evaluation. Whole fresh blackberries remain a nutritious dietary option without the same safety considerations as concentrated extracts.

### What is the difference between Pacific blackberry extract and other blackberry species in supplement form?

Pacific blackberries (Rubus ursinus) contain specific profiles of chlorogenic acid and other phenolic compounds that may differ quantitatively from cultivated blackberry varieties or other Rubus species. The wild-harvested nature of Pacific blackberries may result in more variable phytochemical concentrations compared to standardized cultivated varieties used in some supplements. Currently, there is limited comparative clinical research directly measuring the bioactive potency of Pacific blackberry extracts against other blackberry species in supplement applications.

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*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
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