Eriocitrin

Eriocitrin

1. Identity: Chemical and Botanical Classification

Eriocitrin (eriodictyol glycoside) is a flavanone-7-O-glycoside between the flavanone eriodictyol and the disaccharide rutinose. Also called eriodictyol-7-rutinoside, it is a flavonoid glycoside where rutinose (L-rhamnosyl-D-glucose) is bound with eriodictyol (C₁₅H₁₂O₆; also called 3′,4′,5,7-tetrahydroxyflavanone) belonging to flavanones, a group of flavonoids. Its CAS registry number is 13463-28-0, and it is also known by the synonyms eriodictioside and eriodictyol 7-O-rutinoside.

It is colloquially called "lemon flavonoid" or "citrus flavonoid," one of the plant pigments that bring color to fruit and flowers, and is commonly found in lemons and other citrus fruits. Structurally, eriocitrin belongs to the subclass of flavanone glycosides (dihydroflavonoids), distinguished from flavones by the saturated C2–C3 bond in the central ring.

Natural Sources and Distribution

The distribution of eriocitrin in citrus fruits was found to be especially abundant in lemons and limes; however, it was scarcely found in other citrus fruits. In the case of lemon fruit, eriocitrin was primarily distributed in the peel (about 1,500 ppm) composed of the albedo (mesocarp), flavedo (epicarp), and pulp vesicles. It was also significantly present in the juice (about 200 ppm) but was not detected in the seed. Two varieties of lemon fruits, Eureka and Lisbon, almost had the same eriocitrin content.

One study testing hesperidin, eriocitrin, and diosmin in different parts of mature lemon fruit tissues found that hesperidin and eriocitrin are much more abundant in the albedo than in the flavedo and pulp.

This antioxidant also predominates (38% in one study) in peppermint infusions. Additional citrus species that contain eriocitrin include lime (Citrus aurantifolia), Citrus depressa, Citrus sudachi, Citrus junos, bitter orange (Citrus aurantium), grapefruit (Citrus paradisi), and several other species, though lemon and lime, which are especially rich in eriocitrin, are the preferred raw material.

Eriocitrin (eriodictyol 7-O-beta-rutinoside), belonging to the dihydroflavonoid compound class, is widely found in citrus fruits (lemon, citrus, grapefruit), vegetables, processed products (drinks, wine), and so on.

Physical and Chemical Properties

Identified as eriocitrin (eriodictyol 7-rutinoside) of the flavanone glycoside class by HPLC, ¹H-NMR, and ¹³C-NMR analyses, the purified compound is readily soluble in water, methanol, and ethanol. A water solution of 0.05% eriocitrin is weakly acidic (pH 4.2). Eriocitrin was found to be stable even at high temperature (121°C, 15 min) in acidic solution (pH 3.5).

2. Traditional and Historical Use

Eriocitrin as an isolated compound was not identified and characterized until the late twentieth century; its formal isolation from lemon fruit and characterization of its antioxidative activity was first published in 1997. However, the foods and preparations from which it derives have a much longer documented history of use.

Citrus peels and juices were used in folk remedies to combat scurvy, boost immunity, and promote digestive health. Eriocitrin is a naturally occurring flavonoid predominantly found in citrus fruits, especially lemons; traditionally, diets rich in citrus fruits have been associated with various health benefits, and eriocitrin is considered one of the key compounds contributing to these positive effects. Historically, its presence in lemon peels and other citrus sources has been linked to antioxidant and anti-inflammatory properties, supporting its use in traditional and modern nutritional products.

No traditional pharmacopeial monograph (such as those issued by the WHO, ESCOP, or German Commission E) specifically addresses eriocitrin as an isolated entity. Its traditional significance is therefore understood in the context of historical citrus-based preparations rather than as a standalone phytochemical.

Commercial and Supplement History

Eriocitrin is marketed as a dietary supplement, usually in conjunction with B and C vitamins and other substances, but there is no established medical use or FDA-approved application of the compound. The production of a food material having a high concentration of eriocitrin, derived from citrus fruits, was the subject of early patents, with eriocitrin being recognized as an antioxidant ingredient derived particularly from the flesh, juice, peel, or squeezed residue of lemon or lime. The peel after squeezing, a portion which is commonly discarded, was identified as an especially valuable secondary product from which eriocitrin could be recovered, making its extraction industrially efficient and environmentally meaningful.

3. Key Constituents, Active Compounds, and Mechanisms of Action

Primary Active Compound

Eriocitrin is itself the primary bioactive molecule of interest. Of all the bioactive molecules of lemon, eriocitrin (eriodictyol 7-rutinoside) is a major flavonoid with antioxidant activity. The aglycone liberated after intestinal deglycosylation — eriodictyol — contributes substantially to eriocitrin's biological effects in vivo.

Metabolism and Metabolites

Eriocitrin, a flavonoid glycoside present in lemon fruit, is metabolized in vivo to a series of eriodictyol, methylated eriodictyol, 3,4-dihydroxyhydrocinnamic acid, and their conjugates. Plasma antioxidant activity increased following oral administration of aqueous eriocitrin solutions to rats. Eriocitrin was not detected in plasma and urine; instead, eriodictyol, homoeriodictyol, and hesperetin in their conjugated forms were detected in plasma at 4 hours following administration of eriocitrin. In urine over 24 hours, both non-conjugated and conjugated forms of these metabolites were detected. 3,4-Dihydroxyhydrocinnamic acid, which is metabolized from eriodictyol by intestinal bacteria, was detected in slight amounts.

Using ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS), a total of 32 metabolites in vivo and 27 metabolites in vitro were obtained. Nine metabolites of eriocitrin were identified in rat urine, and seven in various tissues (eriodictyol, homoeriodictyol, hesperetin, and glucuronidated metabolites). Overall, eriocitrin metabolites were widely distributed in the rat tissues, where homoeriodictyol and homoeriodictyol-7-O-glucuronide were the major metabolites.

Antioxidant Mechanisms

Eriocitrin is a flavonoid originally isolated from lemon peel that has antioxidant and enzyme inhibitory activity. The antioxidant action of eriocitrin occurs directly by the uptake of oxygen radicals and the modulation of cell signaling pathways promoting the activation of endogenous defense mechanisms. In preclinical models, eriocitrin was shown to reduce markers of lipid peroxidation and DNA damage present in the liver and kidneys of diabetic rats.

Anti-Inflammatory Mechanisms

Nitric oxide (NO), IL-1β, IL-6, IL-8, TNF-α, NF-κB, MPO, MAPK, and MMP-9 secretion were reduced by eriocitrin, inhibiting cell apoptosis and the production of pro-inflammatory cytokines, while it increases the content of IL-10, Nrf2, DUSP14, HO-1, and NQO1. In a rat cerebral ischemia-reperfusion model, eriocitrin alleviated oxidative injury and inflammatory response through the promotion of Nrf2 activation and the suppression of NF-κBp65 activation.

Lipid Metabolism Mechanisms

Eriocitrin promotes mitochondrial β-oxidation and biogenesis and ameliorates high-fat-diet-induced hepatic steatosis. DNA microarray analysis revealed that eriocitrin increased mRNA of mitochondrial biogenesis genes, such as mitochondria transcription factor, nuclear respiratory factor 1, cytochrome c oxidase subunit 4, and ATP synthase. In HepG2 cells, eriocitrin also induced the corresponding orthologues and reduced lipid accumulation under conditions of lipid loading.

Glycemic and Insulin-Sensitizing Mechanisms

Peroxisome proliferator-activated receptor gamma (PPARγ) agonists are potent insulin sensitizers in treating type 2 diabetes. Despite being very effective in the fight against diabetes-mediated complications, PPARγ agonists are accompanied by severe side effects. A significant research effort is in progress to explore the PPARγ-activating potential of natural compounds. Lemon (Citrus limon) contains various bioactive flavonoids, and eriocitrin is the major flavonoid; it possesses substantial antioxidant, anticancer, and lipid-lowering activities and prevents obesity-associated metabolic diseases.

Eriocitrin reduces hyperglycemia and improves diabetes-related biomarkers in prediabetes patients, and is first metabolized by gut microbiota, producing energy for gut cells and short-chain fatty acids that play a relevant role in glycemic control.

Anticancer Mechanisms

Oxidative stress causes abnormal stimulation of signal transducer and activator of transcription 3 (STAT3) and c-Jun NH₂-terminal kinase (JNK), and p38 mitogen-activated protein kinases (MAPKs) signaling has been strongly connected with the regulation of cell survival and apoptosis of cancer cells. Eriocitrin was found to modulate STAT3/MAPKs signaling activation in MCF-7 cells; it strongly enhances reactive oxygen species (ROS) generation, alteration of mitochondrial outer membrane potential, and enhances apoptotic morphological changes. In lung adenocarcinoma cell lines, eriocitrin, a natural flavonoid compound, exerts anti-inflammatory and anticancer effects, and its anticancer properties include the ability to inhibit the epithelial-mesenchymal transition (EMT) process in lung adenocarcinoma cells, which is partially mediated through induction of ferroptosis in cancer cells.

4. Scientific Evidence by Area of Use

4.1 Antioxidant Activity

Preclinical (animal) evidence: To examine the preventive effect of eriocitrin (eriodictyol 7-O-rutinoside) on oxidative stress during acute exercise in vivo, levels of Nε-(hexanoyl)lysine (HEL), o,o-dityrosine (DT), and nitrotyrosine (NT) were determined in livers of trained rats. Eriocitrin administration prior to exercise significantly suppressed the increases in TBARS caused by lipid peroxidation during acute exercise; the contents of HEL, DT, and NT in rat liver increased dramatically by exercise without eriocitrin administration, but these increases were significantly suppressed by eriocitrin administration before exercise.

Hesperidin, eriocitrin, and eriodictyol were investigated for their prevention of oxidative stress and systemic inflammation caused by high-fat diet in C57BL/6J mice. Mice received a standard diet, a high-fat diet (45% kcal from fat), or a high-fat diet supplemented with hesperidin, eriocitrin, or eriodictyol for four weeks. Hesperidin, eriocitrin, and eriodictyol increased serum total antioxidant capacity and restrained the elevation of interleukin-6 (IL-6), macrophage chemoattractant protein-1 (MCP-1), and C-reactive protein (hs-CRP). In addition, liver TBARS levels and spleen mass were lower for flavanone-treated mice than in unsupplemented mice.

Human/pharmacokinetic evidence: A randomized-crossover human pharmacokinetic study (n = 16) compared the bioavailability and metabolism of flavanones from lemon and orange extracts and postprandial changes in oxidative, inflammatory, and metabolic markers after a high-fat-high-sugars meal. A total of 17 phase-II flavanone-derived metabolites were identified; no significant biomarker changes were observed. However, plasma and urinary concentrations of all metabolites, including hesperetin metabolites, were higher after lemon extract intake.

Evidence strength: The antioxidant effects of eriocitrin are well supported in preclinical models. The single human pharmacokinetic crossover study showed enhanced metabolite exposure compared to hesperidin, but did not detect significant changes in antioxidant biomarkers, likely due to small sample size. Evidence for direct antioxidant outcomes in humans remains preliminary.

4.2 Glycemic Control and Prediabetes

This is currently the area with the strongest human clinical evidence for eriocitrin.

Dose-ranging RCT in prediabetes: A study evaluated the potential effectiveness of different doses of Eriomin® on hyperglycemia and insulin resistance associated with other metabolic biomarkers in prediabetic individuals. Prediabetes patients (n = 103, aged 49 ± 10 years) were randomly divided into four parallel groups: placebo, Eriomin 200 mg, Eriomin 400 mg, and Eriomin 800 mg, with assessments of biochemical, metabolic, inflammatory, hepatic, renal, anthropometric markers, blood pressure, and dietary parameters performed during 12 weeks of intervention. Treatment with all doses of Eriomin (200, 400, and 800 mg) had similar effects and significantly altered the following variables: blood glucose (−5%), insulin resistance (−7%), glucose intolerance (−7%), glycated hemoglobin (−2%), glucagon (−6.5%), C-peptide (−5%), hsCRP (−12%), interleukin-6 (−13%), TNFα (−11%), lipid peroxidation (−17%), systolic blood pressure (−8%), GLP-1 (+15%), adiponectin (+19%), and antioxidant capacity (+6%). Eriomin or placebo did not influence the anthropometric and dietary variables.

Crossover RCT with higher-glycemia participants: A double-blind, randomized, placebo/controlled, crossover study evaluated the efficacy of Eriomin® in reducing hyperglycemia and improving diabetes-related biomarkers in individuals with hyperglycemia above 110 mg/dL (mean 123 ± 18 mg/dL). Subjects (n = 30), divided into two groups (Eriomin or Placebo), received a dose of 200 mg/d of the designated supplement for 12 weeks and, after a washout period of 2 weeks, switched to the other supplement in the following 12 weeks. Assessments of biochemical, metabolic, inflammatory, blood pressure, anthropometry, and dietary parameters were performed at the beginning and end of each intervention. Treatment with 200 mg/d of Eriomin significantly decreased blood glucose (−5%), homeostasis model assessment of insulin resistance (−11%), glucagon (−13%), interleukin-6 (−14%), tumor necrosis factor alpha (−20%), and alkaline phosphatase (−13%); but increased GLP-1 by 17% (P ≤ .05).

Gut microbiota RCT: The aim of this third study was to assess the effect of Eriomin®, a nutraceutical composed of 70% eriocitrin, 5% hesperidin, and 4% naringin, on the microbiota of prediabetic patients. Patients were randomly divided into two groups and received unlabeled capsules of Eriomin® (200 mg/day) or placebo during 12 weeks. After treatment, there was a 6% decrease in hyperglycemia and a 22% increase in GLP-1 blood levels (p < .05). The profile of intestinal microorganisms, obtained by 16S rRNA sequencing of patients' feces, showed changes in microbiota composition, such as lower growth of Firmicutes and less abundance of the Lachnospiraceae family; Ruminococcaceae increased and the Blautia genus reduced with Eriomin® supplementation. Blautia was positively correlated with hyperglycemia reduction.

Evidence strength: There are now at least three published randomized controlled trials — including a dose-ranging parallel-group trial, a double-blind crossover trial, and a microbiota-focused RCT — all using the standardized commercial preparation Eriomin® (predominantly eriocitrin) at 200–800 mg/day over 12 weeks, all showing statistically significant reductions in fasting blood glucose and improvements in inflammatory biomarkers in prediabetic populations. This represents the most robust human evidence for any eriocitrin health application. Notable limitations include the relatively small sample sizes, the use of a standardized multi-flavonoid proprietary blend rather than pure eriocitrin, short intervention durations (12 weeks), and a research group with overlapping authorship across trials. Independent replication by other research groups is needed.

4.3 Lipid Metabolism and Hepatic Steatosis

Rat high-cholesterol model: Eriocitrin was investigated for its lowering effect on serum and hepatic lipids in high-fat and high-cholesterol fed rats. Rats in the control group (n = 6) were fed a 20% lard and 1% cholesterol diet for 21 days, and rats in the 0.35% and 0.70% eriocitrin groups (n = 6 each) were fed a diet supplemented with eriocitrin.

Zebrafish model (with HepG2 corroboration): Feeding experiments on zebrafish with diet-induced obesity were conducted to investigate the mechanism of action of eriocitrin. Oral administration of eriocitrin (32 mg/kg/day for 28 days) improved dyslipidemia and decreased lipid droplets in the liver. DNA microarray analysis revealed that eriocitrin increased mRNA of mitochondrial biogenesis genes, such as mitochondria transcription factor, nuclear respiratory factor 1, cytochrome c oxidase subunit 4, and ATP synthase. In HepG2 cells, eriocitrin also induced the corresponding orthologues and reduced lipid accumulation under conditions of lipid loading.

Mouse low-dose study: At the end of the study, mice supplemented with eriocitrin showed lower levels of blood serum glucose and blood and liver triacylglycerols (P < 0.05). Although earlier studies have reported beneficial effects of eriocitrin in vivo, most have not explored the efficacy of this flavonoid in counteracting obesity-induced metabolic disturbances at doses that would be practicable for humans.

Evidence strength: Evidence for lipid-lowering effects in the liver is moderately consistent across animal models (rats, mice, and zebrafish) and supported by mechanistic in vitro data. No dedicated human lipid-lowering clinical trial has been published for eriocitrin as a standalone compound. Some effect on triglycerides was noted in the human prediabetes RCTs (the placebo group saw a 13% increase, while the Eriomin group did not), but this was a secondary finding.

4.4 Inflammation

A review was conducted on studies of the anti-inflammatory effects of eriocitrin from January 2010 to April 2021. Based on eligibility criteria, six studies were included, consisting of in vitro and in vivo studies. Some pharmacological studies have suggested that eriocitrin has the potential to treat diseases involving inflammatory responses. Human clinical RCT evidence is consistent with anti-inflammatory effects: in both prediabetes trials, Eriomin® significantly reduced circulating IL-6 and TNF-α levels. However, all anti-inflammatory human data comes from studies whose primary aim was glycemic control, and direct anti-inflammatory trials in other conditions have not been conducted in humans.

4.5 Neuroprotection and Cerebrovascular Injury

Animal evidence: One study aimed to detect the effect of eriocitrin on cerebral ischemia-reperfusion (I/R) injury. Seventy male Sprague-Dawley rats were randomly divided into five groups: control, cerebral I/R, and I/R + eriocitrin at 8 mg/kg, 16 mg/kg, and 32 mg/kg. Results showed that eriocitrin significantly reduced the cerebral infarct volume, cerebral water content, and cerebral indexes. Eriocitrin treatment alleviated pathological injury, promoted cell proliferation, and inhibited cell apoptosis. Eriocitrin upregulated SOD activity and downregulated MDA and LDH content. Eriocitrin also effectively decreased the levels of IL-6 and TNF-α, but increased the content of IL-10 in serum and brain tissues. Furthermore, eriocitrin increased the phosphorylation of Nrf2 as well as the expressions of HO-1 and NQO1, and decreased the phosphorylation of NF-κB p65. The researchers concluded that eriocitrin attenuated oxidative injury and inflammatory response in rats with CI/R via the Nrf2/HO-1/NQO1/NF-κB signaling pathway.

Eriocitrin, a dihydroflavonoid compound present in citrus fruits, along with its derivatives hesperetin, hesperidin, eriodictyol, and homoeriodictyol, has been reported to possess various neuroprotective bioactivities, including anti-inflammatory, anti-oxidative, anti-amyloidogenic, anti-tau phosphorylation, and anti-apoptotic properties, in several in vitro and in vivo models.

Evidence strength: Evidence is entirely preclinical (animal and cell models). No human clinical trials for neuroprotection or cerebrovascular indications have been published. Findings are preliminary.

4.6 Anticancer Activity

In vitro and cell-line evidence: Eriocitrin, a lemon flavanone, exhibits several biological properties, including antiproliferative and proapoptotic effects, but its molecular mechanism of action is not entirely clarified. Eriocitrin, derived from lemon and citrate juice, is a natural flavonoid compound. It has been reported to exert multiple biological functions in distinct in vitro settings, such as anti-inflammatory, anti-diabetic, and lipid-lowering effects. Emerging evidence suggests that eriocitrin could inhibit cancer cells' proliferation via diverse mechanisms. Eriocitrin suppressed the proliferation in human hepatocellular carcinoma cells.

Evidence strength: All anticancer evidence for eriocitrin is from cell culture (in vitro) or animal models. There are no published human clinical trials investigating eriocitrin's effects on any cancer endpoint. This evidence is exploratory and cannot support conclusions about efficacy in human cancer.

4.7 Nephroprotection

Animal evidence: Research targeted the protective measure of eriocitrin, a bioactive flavonoid, against cisplatin-induced renal toxicity in rats. Experimental groups received oral administration of eriocitrin (25 and 50 mg/kg body weight) for 10 days, and a single intraperitoneal injection of cisplatin (8 mg/kg body weight) was given on the 7th day for all except the normal control group. The researchers found eriocitrin to reduce markers of oxidative stress and renal injury in this model. Evidence in this area is limited to animal studies.

4.8 Skeletal Muscle

Eriocitrin suppresses muscle atrophy by reducing oxidative stress in the skeletal muscles of mice. This finding derives from a single preclinical study and has not been translated to human research.

5. Body Systems Associated with Eriocitrin

• Metabolic / endocrine system: Glycemic regulation, insulin sensitivity, GLP-1 secretion, adiponectin levels — supported by human RCTs in prediabetic populations.
• Hepatic (liver) system: Lipid metabolism, reduction of hepatic steatosis, mitochondrial biogenesis in liver cells — supported by animal and in vitro evidence.
• Cardiovascular / lipid system: Reduction of serum triglycerides and cholesterol in animal models; anti-inflammatory effects on vascular markers (hsCRP, IL-6) in human studies.
• Immune / inflammatory system: Suppression of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β, NF-κB pathway) — supported by animal and human data.
• Neurological system: Neuroprotection in cerebral ischemia-reperfusion animal models via Nrf2/NF-κB signaling.
• Gastrointestinal / microbiome: Modulation of gut microbiota composition, particularly in prediabetic individuals — supported by one human RCT.
• Antioxidant defense system: Systemic antioxidant activity via direct radical scavenging and induction of Nrf2-mediated endogenous antioxidant enzymes.

6. Dosage Forms and Dosages Reported in Studies

Forms Available

Beyond fresh fruits, eriocitrin can be found in citrus-derived products, such as juices and extracts. Lemon extracts are a concentrated source of this flavonoid. Eriocitrin is also available in supplement form, sometimes combined with other vitamins or compounds. These supplements are often manufactured from citrus by-products of fruit processing. A notable standardized proprietary preparation, Eriomin®, is a nutraceutical composed of 70% eriocitrin, 5% hesperidin, and 4% naringin.

Dosages Used in Published Research

• Human (parallel-group RCT, prediabetes): 200 mg, 400 mg, and 800 mg/day of Eriomin® (an eriocitrin-rich standardized extract) for 12 weeks in 103 prediabetic patients. All three doses produced similar statistically significant effects.
• Human (crossover RCT): 200 mg/day of Eriomin® for 12 weeks, with a 2-week washout period, in 30 individuals with fasting hyperglycemia above 110 mg/dL.
• Human (gut microbiota RCT): 200 mg/day of Eriomin® for 12 weeks in prediabetic patients.
• Zebrafish model: 32 mg/kg/day for 28 days, administered orally.
• Mouse model (high-fat diet): 10 mg/kg, 25 mg/kg, and 100 mg/kg body weight of eriocitrin supplemented into a high-fat diet.
• Rat model (cerebral ischemia-reperfusion): Doses of eriocitrin at 8 mg/kg, 16 mg/kg, and 32 mg/kg in Sprague-Dawley rats.
• Rat model (nephroprotection): Oral administration of eriocitrin at 25 and 50 mg/kg body weight for 10 days.
• Rat model (lipid-lowering): Dietary supplementation with eriocitrin at 0.35% and 0.70% of a high-fat, high-cholesterol diet for 21 days.

No pharmacopeial body or regulatory agency has issued an official daily recommended intake or upper tolerable limit for eriocitrin as an isolated compound.

7. Safety Considerations and Interactions

Regulatory Status

Eriocitrin is marketed as a dietary supplement, usually in conjunction with B and C vitamins and other substances, but there is no established medical use or FDA-approved application of the compound.

Preclinical Safety Data

Eriocitrin is a stronger antioxidant than other citrus flavonoid compounds and is abundant in lemon and lime, with safety proven by the lack of developmental toxicity in zebrafish. In addition, a rat feeding test revealed that lemon flavonoids containing 33% eriocitrin could be administered at ≤2 g/kg/day for 4 weeks without causing any toxicological phenotypic changes, including body weight, feeding volume, urine, hematological and biochemical parameters, organ weight, and histology. There was no phenotypic change at ≤2 g/kg/day.

Pharmacokinetics Relevant to Safety

Eriocitrin metabolites were widely distributed in rat tissues, with the half-lives of the metabolites in plasma between 3 and 3.2 hours, and the total bioavailability of eriocitrin was less than 1%. In a separate rat pharmacokinetic study, the maximum plasma concentration (Cmax) of eriocitrin was 299.833 ± 16.743 μg/L, while the corresponding time to reach Cmax (Tmax) was 0.094 ± 0.019 h, demonstrating rapid absorption from the gastrointestinal tract. The half-time (T1/2) was 1.752 ± 0.323 h, indicating that it would remain in the body for a short time and may need to be given multiple times to enhance clinical efficacy.

Potential Concern: Erythrocyte Effects at High Concentrations

A notable in vitro safety observation has emerged. At anticancer concentrations of eriocitrin (20–100 μM), the compound stimulates premature red blood cell (RBC) death by both hemolysis and eryptosis. However, whether this concentration range is achievable in vivo remains to be determined in future studies. This observation is based on in vitro testing and its clinical relevance is uncertain, but it represents a finding that warrants investigation if very high pharmacological doses are pursued.

Potential Drug Transporter Interactions

While eriocitrin itself is largely considered safe, some citrus flavonoids, including other flavanone rutinosides, have shown potential to interact with certain medications by inhibiting drug transporters like OATP2B1. These interactions are more likely with concentrated forms, such as supplements, rather than typical dietary intake.

Bioavailability Limitation

The hydrophobic nature of eriocitrin lowers its bioavailability and wide applications. However, eriocitrin significantly reduces oxidative stress and inflammatory conditions like diabetes mellitus and atherosclerosis. The higher solubility of eriocitrin versus hesperidin could facilitate the metabolism of eriocitrin to yield phase-II derived metabolites in a shorter time, including eriodictyol-derived metabolites with increased antioxidant activity.

Summary of Human Trial Safety Signals

In the published human RCTs using Eriomin® at 200–800 mg/day for 12 weeks, no serious adverse events were reported in the published results. Eriocitrin has a favorable safety profile, though comprehensive data on potential side effects and interactions with medications are still being gathered.

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