Application of response surface methodology to optimise supercritical carbon dioxide extraction of volatile compounds from Crocus sativus. (28th October 2013) - Shao, Qingsong
Abstract BACKGROUND Crocus sativus has been used as a traditional Chinese medicine for a long time. The volatile compounds of C. sativus appear biologically active and may act as antioxidants as well as anticonvulsants, antidepressants and antitumour agents. In order to obtain the highest possible yield of essential oils from C. sativus, response surface methodology was employed to optimise the conditions of supercritical fluid carbon dioxide extraction of the volatile compounds from C. sativus. Four factors were investigated: temperature, pressure, extraction time and carbon dioxide flow rate. Furthermore, the chemical compositions of the volatile compounds extracted by supercritical fluid extraction were compared with those obtained by hydro‐distillation and Soxhlet extraction. RESULTS The optimum extraction conditions were found to be: optimised temperature 44.9°C, pressure 34.9 MPa, extraction time 150.2 min and CO2 flow rate 10.1 L h−1. Under these conditions, the mean extraction yield was 10.94 g kg−1. The volatile compounds extracted by supercritical fluid extraction and Soxhlet extraction contained a large amount of unsaturated fatty acids. CONCLUSION Response surface methodology was successfully applied for supercritical fluid CO2 extraction optimisation of the volatile compounds from C. sativus. The study showed that pressure and CO2 flow rate had significant effect on volatile compounds yield produced by supercritical fluid extraction. This study is beneficial for the further research operating on a large scale. © 2013 Society of Chemical Industry