Clinical Preclinical Safety Evaluation Of Flos Caryophylli Extract Microemulsion

Caryophylli Flos(CF)is the dried flower buds of Myrtle plant of Eugenia caryophyllata Thunb,with effects of warmming middle burner and tonifying the kidney.Chemical research have shown that volatile oil(17.1%)is the main component of CF,in which eugenol content up to 80.3%.Pharmacological studies have shown that CF have the effects of anti-oxidation,anti-bacteria,anti-inflammation,expel insect and anti-mite.Microemulsion is a kind of oil and water mixted system composed of surfactant and cosurfactant,with advantages such as thermodynamically stable,low viscosity,good dispensability and easily absorbed.In order to provide a scientific basis for clinical application of CF extract microemulsion,acute toxicity test and sub-chronic toxicity test were performed to investigate the safety of CF extract microemulsion on animals.The results are as follows:(1)Acute toxicity test of CF extract microemulsionThe acute toxicity of CF extract microemulsion was evaluated by mouse acute toxicity test,rabbit skin irritation test and ocular conjunctival irritation test.The results showed that the LD50 for CF extract microemulsion by oral administration was higher than 5000 mg/kg,the maximum tolerance dose(MTD)for mouse was 9924 mg/kg,no irritation to rabbit skin and conjunctiva.As a result,CF extract microemulsion is non-toxic and non-irritant..(2)Subchronic Toxicity Test of CF Extract MicroemulsionThe subchronic toxic effects of CF extract microemulsion were evaluated by 28 days continuous oral administrated mice.The results showed that CF extract microemulsion had no significant effects on the clinical manifestations and visceral indexes of mice.The medium and low dose could reduce the body weight gain and the growth rate(P <0.05),high and medium dose could increase the number of neutrophils in mice blood(P <0.05).The levels of urea nitrogen in mice blood were decreased by high,medium and low dose of CF extract microemulsion(P<0.05).Other biochemical indexes were not affected(P>0.05).Histopathological examination showed no significant pathological changes.