Abstract:

The purpose of this study was to validate the microbial limit test method for anticoccidial drug Dichroa febrifuga oral liquid (DFOL),and provide data base for its quality control and researching the new veterinary drug. The direct inoculation method was used to validate the antibacterial activity for DFOL, and the bacterial counting,determination of recovery rate and inspection of control bacteria were measured using a validated test condition and method (conventional method).The results showed that DFOL had no or faint bacteriostasis verified by validated test method, the determination and inspection of bacteria could be determined by conventional method. The normal plate counting were used to detect the amount of Escherichia coli,Staphylococcus aureus, Bacillus subtilis, Candida albicans and Aspergillus niger in DFOL in which the recovery rate were all more than 70%,and the results were not disturbed by sample and diluents. The control bacteria including Escherichia coli,Salmonella paratyphi B,Staphylococcus aureus,and Pseudomonas aeruginosa were tested according to conventional method,whose growth were detected in the test group and positive control group, while no growth were detected in the negative control group and sample group. In conclusion,the microbial limit test method for DFOL had been validated in this study,and the conventional method could be applied to DFOL for bacteria,moulds and yeast counting as well as the inspection for control bacteria. The process of test was in accordance with the regulations of microbial limits test method,the method was convenient and simple,and the results was reliable.

Key words: Dichroa febrifuga oral liquid (DFOL); microbial limit; method validation; conventional method