Herbs (Global Traditional) · Ayurveda
Tulsi (Ocimum sanctum) (Ocimum sanctum)
Strong Evidencebotanical
Hermetica Superfood Encyclopedia
Tulsi (Ocimum sanctum) is an adaptogenic herb containing phenolic compounds like eugenol and rosmarinic acid that provide antioxidant and stress-reducing effects. The herb works by modulating cortisol levels and scavenging free radicals through its bioactive constituents.
Tulsi (Ocimum sanctum), also known as holy basil, is a perennial herbaceous plant native to the Indian subcontinent and widely cultivated in tropical and subtropical regions of Asia. The plant belongs to the Lamiaceae family, with leaves serving as the primary medicinal part, typically extracted using solvents like methanol, ethanol, or n-hexane for isolation of phenolic compounds, flavonoids, terpenoids, and essential oils.
The research dossier explicitly states that search results lack specific details on key human clinical trials, randomized controlled trials (RCTs), or meta-analyses for Ocimum sanctum. No PubMed PMIDs for human studies with sample sizes or outcomes are available, with evidence limited to preclinical and in vitro studies highlighting antioxidant, antibacterial, antiviral, adaptogenic, and immune-enhancing properties.
No clinically studied dosage ranges are available from human trials. Chemical analysis shows essential oil contains eugenol (20.9 g/100 g oil), β-elemene (18.7 g/100 g), and β-caryophyllene (18.5 g/100 g), with methanol extracts containing total phenolics (1.36 g/100 g dry material), but without established clinical dosing guidelines. Consult a healthcare provider before starting any new supplement.
Per 100 g of fresh Tulsi (Ocimum sanctum) leaves: Calories ~23–33 kcal; Protein ~3.0–4.2 g; Total Fat ~0.5–0.7 g; Carbohydrates ~2.6–4.3 g; Dietary Fiber ~1.6–2.0 g; Water ~89–92 g. **Vitamins:** Vitamin A (as beta-carotene) ~2500–3500 IU (~750–1050 µg RAE); Vitamin C ~16–18 mg; Vitamin K ~170–415 µg (variable by cultivar and growing conditions); small amounts of folate (~30–35 µg), riboflavin (~0.1 mg), and niacin (~0.9–1.0 mg). **Minerals:** Calcium ~177–250 mg; Iron ~3.2–4.0 mg (non-heme form, bioavailability enhanced by co-consumption with vitamin C); Magnesium ~64–70 mg; Potassium ~295–330 mg; Phosphorus ~56–60 mg; Manganese ~1.1–1.5 mg; Zinc ~0.8–1.0 mg; Copper ~0.38–0.45 mg. **Key Bioactive Compounds:** Eugenol (primary phenylpropanoid) ~40–71% of essential oil yield (essential oil content ~0.5–1.0% of fresh leaf weight, i.e., ~500–1000 mg oil per 100 g leaves, yielding approximately 200–710 mg eugenol per 100 g fresh leaves); Rosmarinic acid ~2.5–5.6 mg/g dry weight (~0.25–0.56%); Ursolic acid ~0.5–1.5% of dry weight; Oleanolic acid ~0.2–0.8% of dry weight; Apigenin ~0.02–0.1% of dry weight; Luteolin ~0.01–0.05% of dry weight; Orientin and vicenin (flavone C-glycosides) present as minor constituents; Ocimumosides A and B (triterpenoid glycosides, adaptogenic markers); β-caryophyllene ~3–12% of essential oil; Methyl eugenol ~1–8% of essential oil (varies significantly by chemotype — eugenol-rich vs. methyl eugenol-rich); Linalool ~3–8% of essential oil. **Bioavailability Notes:** Eugenol is rapidly absorbed orally with high first-pass metabolism (glucuronidation and sulfation), resulting in moderate systemic bioavailability (~40–65% in animal models); rosmarinic acid has relatively low oral bioavailability (~1–5%) due to ester hydrolysis and phase II conjugation in the gut and liver; ursolic acid is poorly water-soluble with low oral bioavailability (~6–8% in animal models) but may be enhanced by lipid-based formulations or co-administration with piperine; flavonoid glycosides (orientin, vicenin) require gut microbial hydrolysis for aglycone release, affecting absorption kinetics; non-heme iron absorption from Tulsi is inherently low (~2–10%) but is improved with concurrent vitamin C intake; fat-soluble vitamins (A, K) and terpenoids benefit from co-ingestion with dietary fats for improved absorption. Concentrations vary substantially by chemotype (Krishna/purple vs. Rama/green cultivars), geographic origin, harvest season, and drying/processing methods.
Tulsi's phenolic compounds including eugenol, rosmarinic acid, and ursolic acid act as free radical scavengers and reducing agents. These bioactive compounds modulate the hypothalamic-pituitary-adrenal (HPA) axis, helping regulate cortisol production. Computational studies suggest certain compounds may bind to viral proteases, though this requires clinical validation.
Current evidence for tulsi primarily comes from in vitro studies and preliminary computational models rather than robust human trials. Small human studies suggest potential stress-reduction benefits, but sample sizes have been limited and study quality varies. The antiviral activity against COVID-19 remains theoretical based on molecular docking studies without clinical confirmation. More rigorous randomized controlled trials are needed to establish definitive therapeutic effects and optimal dosing protocols.
Tulsi is generally well-tolerated when consumed as tea or in traditional preparations. However, it may lower blood sugar levels and could interact with diabetes medications, requiring monitoring. The herb may also affect blood clotting and should be discontinued before surgery. Pregnant and breastfeeding women should avoid therapeutic doses due to insufficient safety data, though culinary use is typically considered safe.
