Panax quinquefolius (American Ginseng)

Overview

Description: Panax quinquefolius, commonly known as American ginseng, is a perennial herb native to eastern North America. Its root is used as a botanical dietary supplement.
Adaptogenic Properties: Primarily cultivated for its adaptogenic properties, helping the body maintain homeostasis under physical, mental, or environmental stress.

Cognitive Enhancement: Can enhance cognitive performance, particularly working memory and attention, in both healthy adults and individuals with mild cognitive impairment (Kong et al., 2019).
Glucose Metabolism Modulation: Modulates glucose metabolism; randomized trials show reductions in fasting blood glucose and HbA1c in type‑2 diabetes patients (Jin et al., 2021).
Immune Function Support: Supports immune function; standardized extracts increase NK‑cell activity and reduce the duration of upper‑respiratory infections (Kim et al., 2020).
Fatigue Reduction and Endurance Improvement: Reduces fatigue and improves exercise‑related endurance by decreasing cortisol and lactate accumulation (Lee et al., 2022).
Antioxidant and Anti-inflammatory Actions: Exhibits antioxidant and anti‑inflammatory actions, lowering circulating CRP and oxidative stress markers in elderly cohorts (Zhang et al., 2023).
Dose Dependency: All benefits are dose‑dependent and most robust when using standardized extracts (≥ 5 % ginsenosides).

Active Constituents: Bioactivity derives mainly from ginsenosides (e.g., Rb1, Rg1, Re) and polysaccharides.
HPA Axis Modulation: Ginsenosides act as ligands for the glucocorticoid receptor and modulate the hypothalamic‑pituitary‑adrenal (HPA) axis, attenuating stress‑induced cortisol release.
Metabolic Pathway Activation: They also activate the PI3K‑Akt and AMPK pathways, enhancing glucose uptake via GLUT4 translocation in skeletal muscle and adipocytes.
Cognitive Enhancement: In the CNS, ginsenosides enhance synaptic plasticity by up‑regulating BDNF and modulating NMDA‑receptor activity, thereby improving memory consolidation.
Antioxidant Effects: Anti‑oxidant effects stem from scavenging of reactive oxygen species and up‑regulation of Nrf2‑driven antioxidant enzymes (SOD, catalase).
Immunomodulatory Effects: The polysaccharides stimulate Toll‑like receptor 4 (TLR4) signaling, boosting macrophage and NK‑cell activity, which underlies the immunomodulatory effects.

Standard Dosage: Typical adult dosing for standardized American‑ginseng extracts (≥ 5 % total ginsenosides) ranges from 200 mg to 400 mg of extract taken 1–3 times daily, with a total daily intake of 200–800 mg.
Acute Fatigue: For acute fatigue, a single 200 mg dose 30 min before a cognitively demanding task is common.
Chronic Metabolic Support: For chronic metabolic support, 400 mg taken with meals for 8–12 weeks is recommended.
Absorption: Water‑soluble extracts should be taken with food to improve absorption of ginsenosides.
Pediatric Dosage: In children (≥ 6 years) a reduced dose of 100 mg once daily is often used in clinical studies.
Precautions: Adjustments (e.g., lower doses) are advised for elderly individuals or those on anticoagulants; consult a healthcare professional before exceeding 800 mg/day.

General Tolerance: American ginseng is generally well‑tolerated.
Adverse Events: Mild adverse events include insomnia, headache, gastrointestinal upset, and mild hypertension (≤ 5 % incidence).
Contraindications: Contra‑indicated for pregnant or lactating women due to limited safety data.
Drug Interactions: Caution in patients with bleeding disorders or on anticoagulants (warfarin, clopidogrel) because ginsenosides may enhance anticoagulant effects. Potential interactions with insulin, sulfonylureas, and antidiabetic agents may cause hypoglycemia; monitoring of blood glucose is advised.
Medical Supervision: Individuals with autoimmune disease should use under medical supervision.
High-Dose Caution: Long‑term high‑dose (> 1 g/day) use is not recommended due to possible hormonal effects and potential adrenal suppression.

Active Compounds: American ginseng’s pharmacologically active constituents are the dammarane‑type triterpene saponins (ginsenosides).
Rb1 Molecular Formula: The principal ginsenoside Rb1, for example, has the molecular formula C₅₂H₈₈O₁₈.
Rb1 IUPAC Name: The IUPAC name is (2R,3S,5R,6R,20S)-20‑(β‑D‑glucopyranosyl)‑3‑hydroxy‑5,6‑dimethyl‑1‑[3‑(β‑D‑glucopyranosyl)‑2‑[(2‑deoxy‑β‑D‑glucopyranosyl)oxy]‑2‑hydroxy‑5‑hydroxymethyl‑6‑methyl‑3‑oxocyclohex‑1‑en‑1‑yl]‑2‑(2‑hydroxy‑3‑hydroxymethyl‑4‑hydroxy‑5‑methyl‑6‑oxo‑1‑pyrrolidyl)‑2‑[2‑(hydroxymethyl)‑2‑hydroxy‑1‑oxo‑1‑pyrrolidyl]‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1-pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1‑pyrrolidyl‑1-pyrrolidyl (simplified).
Key Features: Key features are a four‑ring dammarane skeleton with multiple sugar moieties at C‑3, C‑12, and C‑20, which determine bio‑availability and pharmacodynamics.

Cultivation Locations: American ginseng is cultivated primarily in Wisconsin, Canada (Ontario, Quebec), and the United States (Maine, New York).
Growing Conditions: The plant grows under forest canopy conditions that maximize ginsenoside content.
Harvesting and Processing: Harvested roots (≥ 4 years old) are cleaned, sliced, and dried at ≤ 55 °C to preserve ginsenosides.
Extraction: Extraction typically employs 70 % ethanol or water‑ethanol mixtures, followed by spray‑drying to produce standardized extracts (e.g., “Panax quinquefolius extract 5 % ginsenosides”).
Quality Control: High‑quality supplements adhere to Good Agricultural and Collection Practices (GACP) and are verified by HPLC‑UV for ginsenoside profile, heavy‑metal, pesticide, and microbial limits.
Organic Certification: Organic‑certified, wild‑crafted sources are rare; cultivated, certified‑organic products are preferred for consistency and sustainability.