Optimization and comparison of extraction technology of flavonoids from jackfruit peel

The aim was to select the suitable method for extracting flavonoids from jackfruit peel, used extraction yield as evaluation index, the flavonoids was extracted by enzymatic assistant ethanol and organic solvent methods.Based on single factor test, an orthogonal design was applied to optimize extraction process.Comparison of the two methods was evaluated for extraction results.The optimum results for the extraction of flavonoids were achieved by ethanol and pectinase assistant extraction. The subsidiary conditions were as follows: additional amount of pectinase 300 U/g, extraction solvent 80% ( v/v) ethanol, temperature 55 ℃, p H value 5.5, time 2.0 h and the substrate concentration 45 g/L.The optimum conditions of organic solvent were found to be extraction at 55 ℃ for 2.5 h using 80% aqueous ethanol with a solid-to-liquid ratio of 1 ∶ 20 ( g/m L) .The highest extraction yield and purity of pectinase enzymolysis method were 4.98% and 12.60%, much higher than 3.05% and8.92% of traditional extraction by organic solvent.Meanwhile, the extraction of enzymatic method revealed stronger antioxidant activity.The results of experiment indicated that the pectinase enzymolysis method was superior to traditional extraction by organic solvent.