[Anti-mite activity and skin safety of Herbal taraxaci extract for Demodex folliculorum].

OBJECTIVE:To test the in vitro effect of the extract of Herbal taraxaci on Demodex folliculorum. METHODS:Active Demodex folliculorum were obtained from patients with moderate to severe demodex infestation. Herbal taraxaci and Radix stemona were extracted respectively with 80% ethanol under 85 degrees C, and a preparation with a concentration of 200mg/ml was made. The extractions were used in vitro to examine the anti-mite activity by observing time of killing mites. Physiological saline and Radix stemona extraction served as blank control and positive control respectively. PH value of Herbal Taraxaci extract was noted. Skin irritation test of normal and wounded skin and acute toxicity test were carried out with rabbit shin, and Herbal taraxaci and 75% ethanol were served as experiment and control medicine. RESULTS:Motion and morphology of the mites considerably changed with the effect of Herbal taraxaci extract. The time of mite-killing was (1.50+/-0.65)min with Herbal taraxaci and (3.53+/-1.04)min with Radix stemona respectively (P<0.01) and over 120 min with physiological saline. pH value of Herbal taraxaci extract was 5.00+/-0.28. Score for irritation to normal and wounded rabbit skin was 0 and 0.3 respectively, and acute toxicity test showed no significant toxicity. CONCLUSION:Herbal taraxaci extract shows a remarkable in vitro activity to Demodex folliculorum with skin safety.