Objective: To explore the most appropriate time reflecting cytotoxicity sensitively

to study the effect of cell inocμLating concentration determining the sensitivity of cytotoxic results. Method: Seven test extracts interacted with L-929 cells (the inoculating concentration was 1×104·mL-1 and 1×105·mL-1) from 1 to 7 days in MTT method to determining the most appropriate day which reflected the cytotoxicity sensitively. Result: The extension of cytotoxicity increased with the extracts interacting with 1×104·mL-1 cells from 1 to 7 days. It was 3 rd day that the cytotoxicity classification became stabilized. The extension of cytotoxicity increased with the extracts interacting with 1×105·mL-1 cells from 1 to 7 days. It was 2nd day that the cytotoxicityrating became stabilized

and from the 5th day the absorbance value of cells decreased. Conclusion: The effect of cytotoxicity has relationship with time. In 1×104·mL-1 inocμLating concentration condition

the shortest appropriate time reflecting cytotoxicity was 72 h. In 1×105·mL-1 inoculating concentration condition

the shortest incubation time reflecting cytotoxicity was 48 h. Increased cell inoculating concentration could shorten the time of cytotoxicity

increase the sensitivity of cytotoxicity.