Korean blackberry
StarRubus coreanus
Traditionally used for
- Energy & fatigue
Western Herbalism Properties
Gallery
Botanical Description
Rubus coreanus, the Korean blackberry or Bokbunja, is a deciduous shrub of the rose family (Rosaceae) native to Korea, Japan and China. It produces arching, biennial canes 2–3 m long that are covered with a conspicuous whitish, waxy bloom and armed with stout recurved prickles. The leaves are pinnately compound, with five to seven ovate, sharply toothed leaflets that are paler beneath. In late spring it bears clusters of pink to reddish flowers, which develop into rounded aggregate fruits ripening from red to deep purple-black. The ripe berries are edible and widely used in Korea to make a fruit wine (bokbunja-ju), while the unripe green fruit is harvested for medicinal use.
Active Constituents
Ellagic acid
Hydroxybenzoic acid (ellagitannin hydrolysis product)Concentration: Principal marker used to standardise unripe-fruit extracts; the 5% ethanol unripe-fruit extract used in the Korean trials is standardised on it
Ellagic acid from unripe fruit blocks the PD-1/PD-L1 interaction in cell-free and cell-based assays and activates T cells. It is also the constituent to which the extract's effect on AMPK, SREBP-2, HMGCR and INSIG-1 signalling is attributed in the cholesterol-metabolism work that preceded the human lipid trial.
Sanguiin H-6
Dimeric ellagitanninConcentration: Major ellagitannin of the fruit; not routinely quantified on commercial certificates of analysis
A casuarictin dimer isolated from Rubus coreanus. In vitro it reduces viability of MCF-7 and MDA-MB-231 breast carcinoma cells and induces caspase-8 and caspase-3 dependent apoptosis, and it does so independently of oestrogen receptor status. No human data.
Cyanidin 3-O-rutinoside
AnthocyaninConcentration: Most abundant of the four major anthocyanins of the ripe fruit
Dominant pigment of the ripe fruit. The anthocyanin fraction of a ripe-fruit extract supplies roughly 47 to 55 per cent of its total antioxidant capacity and protects PC-12 neuronal cells against oxidative stress in a dose-dependent way. This is ripe-fruit chemistry, not the chemistry of the unripe drug.
Cyanidin 3-O-xylosylrutinoside
AnthocyaninConcentration: Second most abundant anthocyanin of the ripe fruit, ahead of cyanidin 3-O-glucoside and cyanidin 3-O-sambubioside
One of four major anthocyanins resolved in ripe fruit by triple-quadrupole and Q-TOF LC/MS. Anthocyanin fingerprints of this kind are the practical means of telling authentic Rubus coreanus fruit from the Rubus occidentalis routinely sold in its place.
Proanthocyanidins
Condensed tannins (oligomeric flavan-3-ols)Concentration: Higher in the unripe fruit; fall as the fruit ripens and anthocyanins accumulate
Transcriptome and metabolite profiling across ripening shows proanthocyanidins and anthocyanins are the two metabolite classes that shift most between unripe and ripe fruit. That shift is the chemical justification for the traditional split, in which the unripe fruit is the medicine and the ripe fruit is food and wine.
⚠ Drug Interactions
Rubus occidentalis supplied as bokbunja
Most Korean black raspberry products sold outside Korea, and a large part of the literature filed under Rubus coreanus, in fact use Rubus occidentalis L. Lee, Dossett and Finn set out the characters that separate the two and showed by anthocyanin fingerprinting that authentic R. coreanus fruit carries a different profile. A patient given a bokbunja supplement is therefore often taking a different species with a different phenolic composition from the one the prescription names.
Clinical note: Require material identified to species, ideally with a voucher or an LC-MS anthocyanin profile. Do not treat published Korean black raspberry supplement data as evidence for R. coreanus without confirming which species the study actually used.
Rubus chingii (Fu Pen Zi)
The drug name 覆盆子 covers two plants. The Chinese Pharmacopoeia specifies the unripe fruit of Rubus chingii Hu, which Chou and colleagues identified as the source plant of the Chinese folk medicine Fu-pen-zi on chemical grounds. Korean practice and the Korean market use Rubus coreanus Miq. under the same name, romanised Bokbunja. The two are botanically and chemically distinct, and a formula written for one is not automatically satisfied by the other.
Clinical note: When a formula calls for Fu Pen Zi, establish which pharmacopoeia the source material follows. Record the binomial on the prescription, not just the pinyin.
Immune checkpoint inhibitors (pembrolizumab, nivolumab, atezolizumab)
Unripe fruit extract and its constituent ellagic acid block the PD-1/PD-L1 interaction and activate T cells in vitro, and in a humanised PD-1/PD-L1 knock-in colorectal cancer mouse the extract augmented the antitumour effect of oxaliplatin. This is the same axis therapeutic checkpoint antibodies act on. No human study has examined co-administration, so whether the result would be added efficacy, added immune-related toxicity, or nothing at all is unknown.
Clinical note: Have the patient disclose bokbunja use to the oncology team before or during checkpoint blockade. There is no human safety data for the combination and no basis for recommending it.
Statins and other lipid-lowering drugs
In a 12-week randomised, double-blind, placebo-controlled trial in 77 adults with borderline-high cholesterol, 600 mg/day of freeze-dried unripe fruit extract lowered total cholesterol by about 21 mg/dL and LDL cholesterol by about 16 mg/dL against placebo. Preclinical work attributes the effect to AMPK, SREBP-2 and HMGCR signalling, which is the pathway statins act on, so the effects should be additive rather than opposing.
Clinical note: Not a reason to avoid the combination, but recheck a lipid panel after starting or stopping the herb rather than attributing the change to the drug.
Drugs cleared by cytochrome P450 enzymes
No CYP inhibition study of Rubus coreanus on its own has been published. The nearest data comes from CP-001, a standardised four-herb mixture containing R. coreanus alongside Houttuynia cordata, Rehmannia glutinosa and Betula platyphylla, which inhibited CYP isozymes in human liver microsomes only weakly, with all IC50 values above 100 micrograms/mL and no time-dependent inactivation. That is reassuring but it does not isolate this herb.
Clinical note: Treat as low risk but not studied. Apply normal caution with narrow-therapeutic-index drugs, and do not cite the CP-001 result as if it tested the single herb.
Dosage Calculator
⚖ Dosage Calculator
A weight-based mathematical estimate for Korean blackberry. Not a prescription.
Evidence Tier
Strong evidence · 5 studiesRecorded studies by study design, strongest design at the top. This is a study-design tier only, not a GRADE rating: it does not weigh risk of bias, consistency or precision.
Systematic review / meta-analysis
0
Randomized controlled trial
3
1 verified · 2 unverified
Show 3 studies
- The cholesterol-lowering effect of unripe Rubus coreanus is associated with decreased oxidized LDL and apolipoprotein B levels in subjects with borderline-high cholesterol levels: a randomized controlled trial
- Effects of Unripe Rubus Coreanus Extract on Upper Body Obesity: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial
- Efficacy of Rubus coreanus Miq. and Astragalus membranaceus Bunge Extract for Postmenopausal Syndrome: A Randomised, Double-Blind, Placebo Comparative Clinical Trial
Other clinical trial
0
Observational / case report
0
In vitro / animal
2
1 verified · 1 unverified
Show 2 studies
- Unripe Black Raspberry (Rubus coreanus Miquel) Extract and Its Constitute, Ellagic Acid Induces T Cell Activation and Antitumor Immunity by Blocking PD-1/PD-L1 Interaction
- Augmented Antitumor Effect of Unripe Rubus coreanus Miquel Combined with Oxaliplatin in a Humanized PD-1/PD-L1 Knock-In Colorectal Cancer Mouse Model
Other / unclassified
0
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
The cholesterol-lowering effect of unripe Rubus coreanus is associated with decreased oxidized LDL and apolipoprotein B levels in subjects with borderline-high cholesterol levels: a randomized controlled trial
Randomised, double-blind, placebo-controlled trial in 77 adults with total cholesterol between 200 and 239 mg/dL, given one 600 mg capsule of freeze-dried unripe fruit extract or placebo daily for 12 weeks. Total cholesterol fell by 21.23 mg/dL and LDL cholesterol by 15.61 mg/dL in the treated arm; apolipoprotein B fell in the treated arm while rising on placebo, and oxidised LDL was lower at 12 weeks. Registered as NCT03649620, though retrospectively. This is the strongest human evidence for the herb and it is for the unripe fruit specifically.
Effects of Unripe Rubus Coreanus Extract on Upper Body Obesity: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial
140 Korean adults aged 19 to 70 with BMI at or above 25 took 800 mg/day of a 5 per cent ethanol unripe-fruit extract or placebo for 12 weeks. Body weight and BMI did not change significantly. The between-group change in upper body fat mass was significant on analysis of covariance; trunk fat mass and percent trunk fat trended down without reaching significance, and no other blood marker differed. Safety parameters stayed within normal ranges in both arms. A modest, regionally specific fat effect, not a weight-loss result.
Efficacy of Rubus coreanus Miq. and Astragalus membranaceus Bunge Extract for Postmenopausal Syndrome: A Randomised, Double-Blind, Placebo Comparative Clinical Trial
Single-centre, double-blind, placebo-controlled trial in women in the menopausal transition or postmenopause, given 2000 mg/day of a combined Rubus coreanus and Astragalus membranaceus extract or placebo for 12 weeks. Kupperman index and Menopause Rating Scale both improved against placebo, with no clinically significant change in laboratory tests or vital signs and no excess of adverse events. Because the product is a two-herb combination, it does not establish an effect for Rubus coreanus alone.
Unripe Black Raspberry (Rubus coreanus Miquel) Extract and Its Constitute, Ellagic Acid Induces T Cell Activation and Antitumor Immunity by Blocking PD-1/PD-L1 Interaction
Extract of the unripe fruit, and ellagic acid isolated from it, blocked the binding of PD-1 to PD-L1 and restored T cell activation in cell-based co-culture assays. Mechanistic in vitro work; it establishes a checkpoint-axis target for the herb but says nothing about clinical antitumour effect.
Augmented Antitumor Effect of Unripe Rubus coreanus Miquel Combined with Oxaliplatin in a Humanized PD-1/PD-L1 Knock-In Colorectal Cancer Mouse Model
In a humanised PD-1/PD-L1 knock-in mouse bearing colorectal tumours, unripe fruit extract added to oxaliplatin produced greater tumour suppression than oxaliplatin alone. Animal study only. Its practical relevance is as a warning that the herb is pharmacologically active on the checkpoint axis, not as support for using it during chemotherapy.
Historical Texts
Dongui Bogam
Joseon Korea, 1613Ming Yi Bie Lu
Southern and Northern Dynasties China, circa 500 CEBen Cao Gang Mu
Ming dynasty China, 1596References
- Lee J, Dossett M, Finn C. Mistaken Identity: Clarification of Rubus coreanus Miquel (Bokbunja) . Molecules (2014) [DOI]
- Lee J, Dossett M, Finn CE. Anthocyanin fingerprinting of true bokbunja (Rubus coreanus Miq.) fruit . Journal of Functional Foods (2013) [DOI]
- Chou WH, Oinaka T, Kanamaru F, Mizutani K, Chen FH, Tanaka O. Diterpene glycosides from leaves of chinese rubus chingii and fruits of R. suavissimus, and identification of the source plant of the chinese folk medicine "Fu-pen-zi" . Chemical and Pharmaceutical Bulletin (1987) [DOI]
- Im SE, Nam TG, Lee H, Han MW, Heo HJ, Koo SI, Lee CY, Kim DO. Anthocyanins in the ripe fruits of Rubus coreanus Miquel and their protective effect on neuronal PC-12 cells . Food Chemistry (2013) [DOI]
- Hyun TK, Lee S, Rim Y, Kumar R, Han X, Lee SY, Lee CH, Kim JY. De-novo RNA Sequencing and Metabolite Profiling to Identify Genes Involved in Anthocyanin Biosynthesis in Korean Black Raspberry (Rubus coreanus Miquel) . PLoS ONE (2014) [DOI]
- Park EJ, Lee D, Baek SE, Kim KH, Kang KS, Jang TS, Lee HL, Song JH, Yoo JE. Cytotoxic effect of sanguiin H-6 on MCF-7 and MDA-MB-231 human breast carcinoma cells . Bioorganic & Medicinal Chemistry Letters (2017) [DOI]
- Yoo HH, Kim SA, Kim IS, Ko SG. The Evaluation of CP-001 (a Standardized Herbal Mixture of Houttuynia cordata, Rehmannia glutinosa, Betula platyphylla, and Rubus coreanus) for Cytochrome P450-Related Herb-Drug Interactions . Evidence-Based Complementary and Alternative Medicine (2013) [DOI]
- Yang JW, Choi IS. Comparison of the phenolic composition and antioxidant activity of Korean black raspberry, Bokbunja, (Rubus coreanus Miquel) with those of six other berries . CyTA - Journal of Food (2016) [DOI]
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.
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