# Frog Liver Extract (Anura)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/frog-liver-extract
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-25
**Evidence Score:** 2 / 10
**Category:** Protein
**Also Known As:** Rana ridibunda liver extract, Anura hepatic extract, Frog hepatocyte concentrate, Amphibian liver protein, Ranidae liver preparation, Anuran hepatic protein extract

## Overview

Frog liver extract (Anura) is a protein-dense organ supplement containing bioactive peptides and hepatic enzymes that demonstrate free radical scavenging activity in vitro. Its primary mechanism involves neutralizing [reactive oxygen species](/ingredients/condition/antioxidant) through hydrogen atom donation, with laboratory IC50 values of 0.39–0.41 mg/mL indicating moderate antioxidant potency.

## Health Benefits

• Antioxidant activity demonstrated in laboratory studies with IC50 values of 0.39-0.41 mg/mL for radical scavenging (preliminary evidence only)
• Protein-rich supplement providing 60.36% protein content (based on extraction studies, not clinical trials)
• [Free radical scaveng](/ingredients/condition/antioxidant)ing potential against DPPH, ABTS, and hydroxyl radicals (in vitro evidence only)
• Traditional medicinal use as a source of bioactive protein compounds (limited documentation)
• Distinct from skin extracts with unique protein-based activity profile (preliminary characterization)

## Mechanism of Action

The [antioxidant activity](/ingredients/condition/antioxidant) of frog liver extract is attributed to hepatic peptides and small molecular weight proteins that donate hydrogen atoms to neutralize free radicals, including DPPH (2,2-diphenyl-1-picrylhydrazyl) and hydroxyl radicals. These bioactive peptides may also chelate transition metal ions such as Fe²⁺ and Cu²⁺, reducing metal-catalyzed oxidative chain reactions. The high protein fraction (approximately 60.36%) contributes electron-rich amino acid residues—particularly tyrosine, tryptophan, and cysteine—that act as direct radical quenchers.

## Clinical Summary

Current evidence for frog liver extract is limited exclusively to in vitro laboratory studies; no published human clinical trials or animal intervention studies specifically examining this extract have been identified in peer-reviewed literature. Extraction studies confirm a protein yield of approximately 60.36% with IC50 values of 0.39–0.41 mg/mL for radical scavenging, placing its potency below that of well-characterized [antioxidant](/ingredients/condition/antioxidant)s like ascorbic acid. Without dose-response data from in vivo models, effective human dosages, bioavailability, and therapeutic endpoints remain entirely unknown. The existing data should be interpreted as preliminary proof-of-concept only, and no health claims can be substantiated for human supplementation at this time.

## Nutritional Profile

Frog Liver Extract (Anura) is a protein-dense ingredient with a documented protein content of approximately 60.36% by dry weight based on extraction studies. The protein fraction contains a diverse amino acid profile typical of vertebrate liver tissue, including essential amino acids such as leucine, isoleucine, valine, lysine, threonine, and methionine, though specific per-amino-acid concentrations from frog liver extraction studies are not yet precisely quantified in available literature. Fat content is relatively low in extracted form, with residual lipids including phospholipids and cholesterol fractions characteristic of hepatic tissue. The extract contains bioactive peptides and polyphenolic compounds contributing to its demonstrated [antioxidant](/ingredients/condition/antioxidant) capacity (IC50 of 0.39–0.41 mg/mL against DPPH, ABTS, and hydroxyl radicals in vitro). Micronutrient composition reflects vertebrate liver characteristics, likely including iron (heme-bound), zinc, copper, selenium, and B-vitamins particularly vitamin B12, riboflavin (B2), and folate, though frog-liver-specific concentrations remain unquantified in peer-reviewed extraction studies. Glycogen content is present in raw hepatic tissue but is largely degraded during extraction processing. Bioavailability of the protein fraction is expected to be moderately high given its animal-source origin and complete amino acid profile, though no human bioavailability trials have been conducted. The extract is devoid of dietary fiber. All nutritional data is derived from laboratory extraction studies, not standardized clinical nutritional analyses.

## Dosage & Preparation

No clinically studied dosage ranges exist for Frog Liver Extract (Anura) as human trials have not been conducted. Extraction studies used freeze-thaw methods yielding 60.36% protein content, but therapeutic dosing has not been established. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

No formal human safety studies, toxicology reports, or tolerability trials for frog liver extract have been published, making its safety profile uncharacterized. Individuals with shellfish or exotic protein allergies may face cross-reactive hypersensitivity risks given the novel animal protein source. Potential contamination concerns include environmental pollutants, heavy metals, and parasites (e.g., Salmonella, trematodes) associated with amphibian tissues if sourcing and processing are not rigorously controlled. Pregnant or breastfeeding individuals, immunocompromised patients, and those on anticoagulant or hepatic-metabolized medications should avoid this supplement entirely until safety data are established.

## Scientific Research

No human clinical trials, randomized controlled trials (RCTs), or meta-analyses have been conducted on Frog Liver Extract (Anura). All available research is limited to in vitro [antioxidant activity](/ingredients/condition/antioxidant) assessments and extraction optimization studies, with no PubMed PMIDs available for human trials.

## Historical & Cultural Context

Forest frog (Rana ridibunda) has been used in traditional medicine as a source of active protein compounds, though specific historical applications for liver extracts are not well-documented. Unlike the broader traditional use of anuran skin extracts, liver use appears more modern and research-oriented.

## Synergistic Combinations

Other [antioxidant](/ingredients/condition/antioxidant) proteins, vitamin C, vitamin E, selenium, [glutathione](/ingredients/condition/detox)

## Frequently Asked Questions

### What is frog liver extract and what is it used for?

Frog liver extract is a dietary supplement derived from the hepatic tissue of frogs in the order Anura, marketed primarily for its antioxidant and protein-supplementation properties. Laboratory studies show it contains approximately 60.36% protein and bioactive peptides capable of scavenging free radicals at IC50 values of 0.39–0.41 mg/mL. Its use in humans remains speculative, as no clinical trials have validated these in vitro findings in a living system.

### How does frog liver extract compare to other antioxidant supplements?

In vitro, frog liver extract demonstrates an IC50 of 0.39–0.41 mg/mL for DPPH radical scavenging, which is measurably weaker than ascorbic acid (vitamin C), which typically shows IC50 values below 0.05 mg/mL under comparable assay conditions. It may be broadly comparable to some plant-based peptide extracts in radical scavenging potency, but direct comparative studies are absent. Without human bioavailability data, any ranking of its real-world antioxidant efficacy relative to established supplements is premature.

### What is the protein content of frog liver extract?

Extraction studies report frog liver extract contains approximately 60.36% protein by dry weight, making it a protein-dense organ-derived supplement. The protein fraction is thought to include structural hepatic proteins, enzymes, and short bioactive peptides rich in amino acids such as tyrosine, cysteine, and tryptophan. However, these figures come from laboratory extraction protocols, not standardized supplement manufacturing, so commercial product protein content may vary significantly.

### Are there any side effects or safety risks of taking frog liver extract?

No formal human safety or toxicology data exist for frog liver extract, so its side effect profile is unknown. Key risks include allergic reactions to novel amphibian proteins, potential exposure to environmental contaminants such as heavy metals and pesticides bioaccumulated in frog tissues, and parasitic or bacterial contamination (including trematodes and Salmonella species) if the raw material is not properly processed. Until safety studies are conducted, this supplement should be treated as uncharacterized and used with extreme caution, if at all.

### Is there any clinical evidence that frog liver extract works in humans?

As of the available published literature, there are no human clinical trials, randomized controlled studies, or animal intervention studies demonstrating efficacy of frog liver extract in vivo. All existing evidence comes from in vitro laboratory assays measuring radical scavenging activity and protein composition. This means there is currently no scientific basis to recommend frog liver extract for any specific health condition or therapeutic purpose in humans.

### What is the sustainable sourcing status of frog liver extract supplements?

Frog liver extract sourcing raises conservation concerns, as many amphibian species face population decline due to habitat loss, disease, and overharvesting. Reputable suppliers should provide documentation of ethical sourcing practices and compliance with CITES regulations for protected species. Consumers concerned about sustainability may want to inquire whether manufacturers use farmed amphibians versus wild-caught sources.

### How is frog liver extract processed, and does processing affect its potency?

Frog liver extract is typically produced through solvent extraction methods that isolate bioactive compounds from raw liver tissue, with the extraction efficiency and final antioxidant activity varying based on solvent type and processing conditions. Processing variables such as temperature, pH, and extraction duration can significantly impact the concentration of radical-scavenging compounds and overall product potency. Standardization of extraction methods remains inconsistent across manufacturers, which may lead to variable product quality.

### Is frog liver extract regulated as a dietary supplement or pharmaceutical ingredient in different countries?

Regulatory status of frog liver extract varies significantly by country; it may be classified as a dietary supplement in some regions while being restricted or banned in others due to amphibian conservation laws and endangered species protections. In the United States, it would typically fall under dietary supplement regulations if marketed, while European countries may have stricter requirements or prohibitions based on species sourcing. Consumers should verify local regulations and manufacturer compliance before purchasing, particularly in countries with strong wildlife protection frameworks.

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