Study on the Extraction Process of Volatile Oil in Xiaoqinglong Plaster

Objective To optimize the best conditions of the extraction process of volatile oil in xiaoqinglong plaster.Methods L9(34)orthogonal test was adopted.The extraction rate of volatile oil was taken as the observation index.It was to observe the impacts of water amount,soak time and extraction time on the extraction rate of volatile ole in xiaoqinglong plaster.Results The extraction and soak time brought the best impact on the extraction of volatile oil,presenting the best significance.The water volume impacted less on the results.In consideration with the actual production,the final decision of the extraction process of volatile oil in xiaoqinglong plaster was:adding water 8 times as the weight of herbal materials,soaking for 1 h,steam distillation for 6 h.Conclusion In the verification test,the extraction rate of xiaoqinglong plaster of 3 batches is stable;the optimized extraction process of volatile oil is simple,stable and feasible.This process is suitable to be applied in the industrialized production.