Abstract: 【Objective】 The experiment was aimed to enrich the dosage form of compound Ku Xuan Shen granules for the prevention and control of bacterial diarrhea in livestock and poultry, develop compound Ku Xxuan Shen oral liquid, and control its quality, lay a pharmacological foundation for later clinical trials. 【Method】 Based on the basis of the previous experiments, the applicability of the joint use of 0.25% benzoic acid and 0.075% sorbic acid as preservatives was evaluated, and the suitable antioxidants among 0.025%-0.100% sodium bisulfite, sodium metabisulfite and ascorbic acid were screened.TLC identification and analysis method for the four medicinal materials of Picria felterrae Lour., Cortex ilicis Rotundae, root of Rhodomyrtus tomentosa and Artemisia anomala S.Moore in the prescription and a HPLC method for the content determination and analysis of the standard component of picroside IA in the royal medicine Picria felterrae Lour. were established.The quality control of oral liquid was carried out according to the relevant provisions of the 2020 edition of the Veterinary Pharmacopoeia of the People’s Republic of China. 【Result】 Adding 0.25% benzoic acid and 0.075% sorbic acid as preservatives, the viable counts of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Aspergillus niger and Candida albicans in the compound Ku Xuan Shen oral liquid met the criteria for bacteriostatic efficacy on the 14th and 28th day, which indicated that the combination of the preservative had a good anticorrosive effect.Compared with the negative samples, the degradation of picroside IA decreased from 7% to 1.38% at 10 d with the addition of 0.075% sodium metabisulphite as antioxidant, which significantly enhanced the stability of the compound Ku Xuan Shen oral liquid.TLC results showed that the fluorescent spots of Picria felterrae Lour., Cortex ilicis Rotundae, root of Rhodomyrtus tomentosa and Artemisia anomala S.Moore in the oral liquid of compound Kuan Xuan Shen and the control or control herbs were in the same colour in the corresponding positions, which indicated that the specificity of the established TLC method was good.The HPLC results showed good linearity in the range of 14.063 to 450 μg/mL (R²=0.9996) for picroside IA, the active ingredient of Picria felterrae Lour., and the relative standard deviation (RSD) of the results of the precision test, reproducibility test, stability test were 1.02%, 0.44% and 0.60%, respectively.The average recovery was 98.50% with the RSD of 0.56%, which indicated that the established HPLC method of compound Ku Xuan Shen oral liquid met the methodological requirements in terms of specificity, linearity, stability and accuracy.The average values of the content of picroside IA in the three batches of compound Ku Xuan Shen oral liquid were 214.97, 213.85 and 214.82 μg/mL, respectively, and the RSD was 0.38%.Other quality control indicators such as yellow-brown appearance and properties, relative density was 1.039 to 1.055 g/mL, with RSD of 0.88%, pH was 5.50 to 5.66, with RSD of 0.72%, microbiological limits, etc.were in accordance with the relevant provisions of the 2020 edition of the Veterinary Pharmacopoeia of the People’s Republic of China for oral liquids. 【Conclusion】 The compound Ku Xuan Shen oral liquid prepared in this study had a simple process, accurate and reliable quality control method, and could be used for subsequent pilot production and quality control.

Key words: compound Ku Xuan Shen oral liquid; picroside IA; content determination; preparation process; quality standards