Experimental Study On Extraction Of Chlorophyll From Leaves Of Phyllostachys Edulis With Supercritical Carbon Dioxide

Extraction of chlorophyll from leaves of phyllostachys edulis with supercritical carbon dioxide were thoroughly investigated in this article. Based on lots of experimental studies and analyses, the optimal extraction condition was determined, which is pressure 24Mpa and temperature 50 C of extraction cell, the rate flow of CO₂ 60g/h, particle size 60 meshes of raw material, 10% ethanol as entrainer and extraction time of 80min. Experiment of the optimal condition was repeated at 8 times. The recovery rate is 3.53‰,3.50‰,3.53‰,3.53‰,3.49‰, 3.51‰,3.51‰,3.56‰, 3.52‰and the average recovery rate is 3.52‰. The results show that this method is well repeatability.The stability of chlorophyll from phyllostachys edulis was analyzed in this article. The effects of temperature, pH, concentration of oxidant and existence of Fe³⁺, Zn²⁺, Cu²⁺ on the stability of chlorophyll were evaluated. Results show that the primary factors are the temperature, PH, concentration of oxidant, and the existence of Zn²⁺, Cu²⁺ have marked but irregular effect on the stability of chlorophyll, nevertheless it shows good stability with the existence of Fe³⁺.Based on the experimental results, the prediction model by Back Propagation (BP) neural network for extraction of chlorophyll from leaves of phyllostachys edulis with supercritical carbon dioxide was established in this article. Extraction of chlorophyll from leaves of phyllostachys edulis with supercritical carbon dioxide was predicted with this model. The prediction results con-elated by this model were in fairly good agreement with the experimental data.