Three statistical experimental designs for enhancing yield of active compounds from herbal medicines and anti‑motion sickness bioactivity

Background: Since antiquity, Zingiber officinale (ginger), pogostemonis herba, and radix aucklandiae have been used as traditional Chinese medicines to remit gastrointestinal discomfort. Recent evidences also show the efficacy of the three herbal medicines against nausea and vomiting. Objective: To optimize the CO2 supercritical fluid extraction (SFE‑CO2) conditions for ginger and the ethanol reflux extraction conditions for radix aucklandiae, control the quality of pogostemonis herba essential oil, and evaluate anti‑motion sickness activity of the compound recipes composed of the three herbal medicine extracts. Materials and Methods: Two orthogonal array designs L9 (3)4 were employed to optimize the SFE‑CO2 conditions for enhancing yield of 6‑gingerol from ginger and the ethanol reflux extraction conditions for enhancing yield of costunolide and dehydrocostus lactone from radix aucklandiae; a uniform design U5(53) was applied for evaluation of anti‑motion sickness activity of the compound recipes. Results: Extraction pressure (P < 0.01), extraction temperature and extraction time (P < 0.05) have significant effects on the yield of 6‑gingerol from ginger by SFE‑CO2; ethanol concentration (P < 0.01) and times of repeating extraction (P < 0.05) have significant effects on the total yield of costunolide and dehydrocostus lactone from radix aucklandiae by ethanol reflux extraction; the anti‑motion sickness effects of the optimized compound recipe composed of the three herbal medicine extracts were markedly better than those of dimenhydrinate. Conclusion: The compound recipe composed of ginger, pogostemonis herba, and radix aucklandiae could be developed as a promising anti‑motion sickness medicine.