Compound Monograph
Sakuranetin
Sakuranetin is the 7-O-methyl ether of naringenin and the major inducible phytoalexin of rice — the flavanone rice makes on demand to fight off blast fungus. Its most developed therapeutic evidence is a preclinical anti-asthma/airway-remodeling story in mice; its antimicrobial, antiparasitic and antiviral activity are all in vitro. No human trials of the isolate; poorly absorbed and rapidly conjugated.
Sources · 6
Where Does It Come From?
Sakuranetin is a naturally occurring flavanone (flavonoid), found in Rice — inducible leaf phytoalexin, Cherry and related Prunus species, Yerba Santa and 3 other sources. It is well tolerated orally (low toxicity).
Source Jurema Mimosa tenuiflora Herb monograph → 
Source Yerba Santa Eriodictyon californicum Herb monograph → Concentration
Content by Source
Concentrations not reported. No percent-dry-weight or mg/g figures have been published for this compound in its source plants.
Sakuranetin at a Glance
Sakuranetin is the 7-O-methyl ether of naringenin and the major inducible phytoalexin of rice — the flavanone the plant manufactures on demand when attacked by blast fungus, rather than storing in advance.
Its most developed therapeutic evidence is preclinical anti-asthma and airway work, where it has shown activity in allergic airway inflammation models.
What It's Used For
Sakuranetin is the 7-O-methyl ether of naringenin — and its honest identity is botanical: it is the principal inducible flavonoid phytoalexin of rice, biosynthesized from naringenin by naringenin 7-O-methyltransferase on demand after UV, jasmonate or blast-fungus (Magnaporthe oryzae) attack 4Reference 4Naringenin 7-O-methyltransferase involved in the biosynthesis of the flavanone phytoalexin sakuranetin from riceView study →.
That antifungal role is plant self-defense, not human therapeutics. Its most developed therapeutic literature is a preclinical anti-asthma/airway-remodeling story in mice; its antimicrobial, antiparasitic and antiviral activities are all in vitro. There are no human trials of the isolate.
Support is an experimental score — weighted by study type (human > animal > in vitro) and volume. A beta, not a validated metric. No human isolate data, so scores stay low by design.
Sakuranetin’s most developed therapeutic literature. In ovalbumin-sensitized mice, intranasal/systemic sakuranetin (~20 mg/kg) reduced airway hyperresponsiveness, eosinophilic/neutrophilic infiltration, Th2/Th17 cytokines, serum IgE and mucus, and reversed airway/peribronchial remodeling (collagen, elastic fibers) 1Reference 1AnimalFlavanone treatment reverses airway inflammation and remodeling in an asthma murine modelView study →, via NF-κB suppression plus inhibition of MAPK (ERK1/2, JNK, p38) and STAT3–SOCS3 signaling 2Reference 2AnimalInhibition of MAPK and STAT3–SOCS3 by sakuranetin attenuated chronic allergic airway inflammation in miceView study →.
Gap: a single lab lineage, rodent-only, with no inhaled/oral human PK bridge and no clinical data 1,
As a phytoalexin, sakuranetin is directly antifungal against rice blast 3Reference 3Analysis of the blast-fungus-responsive characters of the flavonoid phytoalexin sakuranetinView study →; from Baccharis retusa it showed antileishmanial and antitrypanosomal activity 5Reference 5In-vitro antileishmanial and antitrypanosomal activities of flavanones from Baccharis retusaView study →, and in cell culture it inhibited human rhinovirus 3 6Reference 6In-vitro antiviral activity of sakuranetin against human rhinovirus 3View study → and influenza B (acting at attachment/entry/post-entry) 7Reference 7Suppression of influenza B virus replication by sakuranetin and the mode of its actionView study →.
Gap: all in-vitro, at weak-to-moderate µg/mL potencies, with no in-vivo infection efficacy or mammalian selectivity data — and the antifungal biology is rice self-defense, not a human antifungal claim 3,
Sakuranetin’s antioxidant activity is a mechanistic contributor to its anti-inflammatory effect (oxidative-stress reduction in airway models) rather than a standalone indication 1,
Gap: no isolate outcome studies — typical flavanone radical scavenging, not distinctive 9Reference 9ReviewA review on sources and pharmacological aspects of sakuranetinView study →.
Sakuranetin is a member of the yerba-santa cancer-chemopreventive fraction identified in a 1992 screen 11Reference 11Isolation of potential cancer-chemopreventive agents from Eriodictyon californicumView study →.
Gap: a fraction-level/association claim with no dedicated in-vivo tumor efficacy for the isolate 11Reference 11Isolation of potential cancer-chemopreventive agents from Eriodictyon californicumView study →.
Mechanisms
| Target / pathway | Effect | Relevant to |
|---|---|---|
| NF-κB | ↓ activation (in-vivo airway) | anti-inflammatory / asthma |
| MAPK (ERK1/2, JNK, p38); STAT3–SOCS3 | ↓ phosphorylation; ↓ IL-17 | Th17-driven airway inflammation |
| Th2/Th17 cytokines, IgE, eosinophils, mucus | reduced | allergic-asthma phenotype |
| Fungal / parasite / viral targets | direct growth/replication inhibition (entry/post-entry for influenza B) | antimicrobial breadth |
| CYP450s / UGTs (esp. UGT1A3) | substrate + modulator | pharmacokinetics / interaction signal |
Pharmacokinetics
Sakuranetin is a flavanone aglycone with poor oral bioavailability typical of the class — presystemic elimination in gut and liver. It undergoes rapid phase-II glucuronidation (UGT1A3 responsible for >80%) in mouse/rat/dog microsomes but is comparatively stable in human liver microsomes — a notable species difference — and is also 7-O-demethylated back to naringenin 8Reference 8Hepatic metabolism of sakuranetin and its modulating effects on cytochrome P450s and UDP-glucuronosyltransferasesView study →. Because it modulates CYP450s and UGTs, a theoretical drug-metabolism-interaction signal exists (in vitro only), and no human oral pharmacokinetic parameters are reported for the isolate.
Clinical trials
There are no human clinical trials of isolated sakuranetin for any indication; all efficacy evidence is in-vitro or rodent.
| Completed | Planned | Terminated | Preclinical |
|---|---|---|---|
| —(none, isolate) | — | — | Moderate(rodent-asthma-led) |
Last checked: July 2026.
Toxicity & Safety
Sakuranetin looks benign in the little data that exists — no cytotoxicity in cell assays, well tolerated in mice — but the safety file is essentially empty: no repeat-dose, genotoxicity or reproductive studies, and no human exposure to the isolate at all.
- Low apparent toxicity. No cytotoxicity at antiviral test concentrations and good tolerability at efficacious doses in mouse asthma models.
- Avoid concentrated doses in pregnancy and lactation. Dietary trace is fine.
- CYP and UGT modulation. A theoretical herb–drug interaction signal, in vitro only.
- No safety studies exist. No dedicated repeat-dose, genotoxicity or reproductive-toxicity work has been done.
Full Safety & Interactions Detail
Sakuranetin has low apparent toxicity in the available data — no cytotoxicity at antiviral test concentrations (≤100 µg/mL in HeLa) 6Reference 6In-vitro antiviral activity of sakuranetin against human rhinovirus 3View study → and good tolerability at efficacious doses in mouse asthma models 1,
No dedicated repeat-dose, genotoxicity or reproductive-toxicity studies exist, and the main theoretical caution is CYP/UGT modulation with herb–drug-interaction potential 8Reference 8Hepatic metabolism of sakuranetin and its modulating effects on cytochrome P450s and UDP-glucuronosyltransferasesView study →.
As a bitter-receptor (hTAS2R31) antagonist in a cell assay 10Reference 10In-vitro evaluation of flavonoids from Eriodictyon californicum for antagonist activity against the bitterness receptor hTAS2R31View study →, it shares yerba santa’s taste-modifying biology — a flavor finding, not a therapeutic mechanism.
Dosage
There is no established human dose — no isolate is sold or dosed clinically. Rodent efficacy used ~20 mg/kg in asthma models, which is not translatable to a human dose, so the honest answer is that no dose is established.
References
- Toledo AC, et al. (2013). Flavanone treatment reverses airway inflammation and remodeling in an asthma murine model. British Journal of Pharmacology. https://pubmed.ncbi.nlm.nih.gov/23170811/
- Santana FPR, et al. (2019). Inhibition of MAPK and STAT3–SOCS3 by sakuranetin attenuated chronic allergic airway inflammation in mice. Mediators of Inflammation. https://pubmed.ncbi.nlm.nih.gov/31565031/
- Hasegawa M, et al. (2014). Analysis of the blast-fungus-responsive characters of the flavonoid phytoalexin sakuranetin. Molecules. https://pubmed.ncbi.nlm.nih.gov/25093982/
- Rakwal R, et al. (2000). Naringenin 7-O-methyltransferase involved in the biosynthesis of the flavanone phytoalexin sakuranetin from rice. Plant Science. https://pubmed.ncbi.nlm.nih.gov/10814825/
- Grecco SS, et al. (2012). In-vitro antileishmanial and antitrypanosomal activities of flavanones from Baccharis retusa. Experimental Parasitology. https://pubmed.ncbi.nlm.nih.gov/22143090/
- Choi HJ (2017). In-vitro antiviral activity of sakuranetin against human rhinovirus 3. Osong Public Health and Research Perspectives. https://pubmed.ncbi.nlm.nih.gov/29354400/
- Kwon DH, Ji JH, Yim SH, et al. (2018). Suppression of influenza B virus replication by sakuranetin and the mode of its action. Phytotherapy Research. https://pubmed.ncbi.nlm.nih.gov/30187587/
- Jeong H, Lee J, Kim S, et al. (2018). Hepatic metabolism of sakuranetin and its modulating effects on cytochrome P450s and UDP-glucuronosyltransferases. Molecules. https://pubmed.ncbi.nlm.nih.gov/29949932/
- Stompor-Gorący M, et al. (2020). A review on sources and pharmacological aspects of sakuranetin. Nutrients. https://pubmed.ncbi.nlm.nih.gov/32085443/
- Fletcher JN, Kinghorn AD, Slack JP, et al. (2011). In-vitro evaluation of flavonoids from Eriodictyon californicum for antagonist activity against the bitterness receptor hTAS2R31. Journal of Agricultural and Food Chemistry. https://pubmed.ncbi.nlm.nih.gov/22059530/
- Liu YL, et al. (1992). Isolation of potential cancer-chemopreventive agents from Eriodictyon californicum. Journal of Natural Products. https://pubmed.ncbi.nlm.nih.gov/1593282/
