Tao Ren (Prunus persica seed)

Tao Ren (Prunus persica seed, peach kernel) contains approximately 45-50% fixed oils (primarily oleic acid ~55-70%, linoleic acid ~20-30%, palmitic acid ~5-8%, and stearic acid ~2-4%), 25-30% protein, and 4-6% crude fiber per dry weight. Key bioactive compounds include amygdalin (approximately 2-4% by weight), a cyanogenic glycoside considered the principal pharmacologically active constituent, along with prunasin (a related glycoside, ~0.5-1%). The seed is rich in emulsin (an enzyme complex including β-glucosidase), which is relevant to amygdalin metabolism. Micronutrient content includes magnesium (~250-270 mg/100g), phosphorus (~400-450 mg/100g), potassium (~600-700 mg/100g), iron (~3-5 mg/100g), zinc (~3-4 mg/100g), calcium (~50-70 mg/100g), and selenium (~2-5 µg/100g). Vitamin content includes vitamin E (primarily γ-tocopherol, ~15-25 mg/100g), vitamin B1 (thiamine, ~0.1-0.3 mg/100g), vitamin B2 (riboflavin, ~0.1-0.2 mg/100g), and niacin (~1-3 mg/100g). Additional bioactive constituents include flavonoids (naringenin, kaempferol derivatives), phytosterols (β-sitosterol ~100-200 mg/100g, campesterol), and polyphenolic compounds with antioxidant activity. The seed also contains volatile oils and tannins in minor amounts. Bioavailability notes: Amygdalin has moderate oral bioavailability but is metabolized by gut microbiota and enzymatic hydrolysis, releasing benzaldehyde and trace hydrocyanic acid (HCN), which necessitates controlled dosing (typical TCM therapeutic dose: 4.5-9 g of raw herb). Processing methods such as stir-frying (chao) reduce amygdalin content by 30-50%, improving safety. Fat-soluble compounds (tocopherols, phytosterols) show enhanced absorption when consumed with dietary fats. Mineral bioavailability may be modestly reduced due to the presence of phytic acid (~1-2%) in the seed matrix.