Yokukansan (Restrain the Liver Powder)

Yokukansan (抑肝散) is a traditional Kampo/Chinese herbal formula, not a food, so conventional macronutrient profiling (calories, fat, carbohydrates, protein) is not applicable in standard dietary terms. Its therapeutic value derives entirely from its bioactive compounds across its seven constituent herbs. Typical formulation (per daily dose, ~7.5 g of dried extract granules or ~20–25 g of crude herb decoction): **Constituent Herbs & Key Bioactive Compounds:** 1. **Atractylodes lancea rhizome (Sōjutsu/Cangzhu, ~4.0 g crude):** Atractylodin (~0.3–0.8 mg/g), atractylone, beta-eudesmol; sesquiterpenoids with anti-inflammatory and gastrointestinal-modulating activity. 2. **Poria cocos (Bukuryō/Fuling, ~4.0 g crude):** Pachymic acid (~0.5–2.0 mg/g), triterpenoids (dehydropachymic acid, tumulosic acid), polysaccharides (beta-glucans, ~2–5% w/w); supports mild diuretic and immunomodulatory effects. Provides trace potassium and magnesium. 3. **Cnidium officinale rhizome (Senkyū/Chuanxiong, ~3.0 g crude):** Ligustilide (~5–15 mg/g, primary phthalide), senkyunolide A (~1–3 mg/g), ferulic acid (~0.5–1.5 mg/g); these phthalides and phenolic acids promote cerebral vasodilation and exhibit antioxidant properties. Ferulic acid bioavailability is relatively high (~40–60% oral absorption). 4. **Angelica acutiloba root (Tōki/Danggui, ~3.0 g crude):** Z-ligustilide (~3–10 mg/g), ferulic acid (~0.5–2.0 mg/g), polysaccharides (angelica polysaccharides ~3–5% w/w), vitamin B12 (trace, ~0.05–0.2 µg/g), folic acid (trace), iron (trace, ~0.1–0.5 mg/g crude herb). Supports hematopoiesis. Ferulic acid shows good oral bioavailability. 5. **Bupleurum falcatum root (Saiko/Chaihu, ~2.0 g crude):** Saikosaponins a, c, and d (~5–15 mg/g total); triterpenoid saponins with anti-inflammatory, hepatoprotective, and corticosteroid-modulating activity. Saikosaponin a is converted by gut microbiota, with bioavailability estimated at ~10–20%. 6. **Glycyrrhiza uralensis root (Kanzō/Gancao, ~1.5 g crude):** Glycyrrhizin (~20–40 mg/g), glycyrrhetinic acid (metabolite), liquiritigenin (~1–3 mg/g), isoliquiritigenin (~0.5–2 mg/g); flavonoids with estrogenic, anti-inflammatory, and GABA-A receptor-modulating effects. Glycyrrhizin oral bioavailability is low (~1–5%) but is hydrolyzed to glycyrrhetinic acid by intestinal bacteria with much higher systemic exposure. Contains trace minerals including manganese and zinc. 7. **Uncaria rhynchophylla hook (Chōtōkō/Gouteng, ~3.0 g crude):** Geissoschizine methyl ether (GM, ~0.5–2.0 mg/g) — a key indole alkaloid acting as a partial agonist at serotonin 5-HT1A receptors and antagonist at 5-HT2A, 5-HT2C, and dopamine D2 receptors; rhynchophylline (~2–6 mg/g), isorhynchophylline (~1–4 mg/g), hirsutine (~0.5–2 mg/g); oxindole and indole alkaloids with neuroprotective, anti-glutamatergic, and calcium channel-blocking activity. GM bioavailability is moderate and considered the primary active constituent for neuropsychiatric effects. **Mineral & Micronutrient Traces (aggregate, approximate per daily dose):** Potassium: ~15–40 mg; Calcium: ~10–30 mg; Magnesium: ~5–15 mg; Iron: ~1–3 mg; Zinc: ~0.2–0.8 mg; Manganese: ~0.3–1.0 mg. **Fiber/Polysaccharides:** Total soluble polysaccharides from Poria, Angelica, and Atractylodes contribute approximately 200–500 mg per daily dose, with prebiotic-like effects on gut microbiota. **Bioavailability Notes:** Many active compounds (saikosaponins, glycyrrhizin, oxindole alkaloids) undergo extensive first-pass hepatic metabolism and gut microbial biotransformation, significantly altering their systemic bioactive profiles. Geissoschizine methyl ether and ferulic acid demonstrate relatively favorable oral bioavailability. Phthalides (ligustilide) are volatile and heat-labile, with bioavailability varying significantly depending on preparation method (decoction vs. granule extract). Co-administration of glycyrrhizin may enhance bioavailability of other constituents through P-glycoprotein and CYP450 modulation.