The linear range for the assay of atractylodin, pachymic acid, heptamethoxyflavone, naringenin, nobiletin, liquiritigenin, isoliquiritigenin, and 18β-glycyrrhetinic acid were 200–20,000, 10–1,000, 4–400, 50–5,000, 4–400, 2–200, 2–200, and 800–80,000 pg/mL, respectively.
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