Extraction Of Varieties Of Effective Components In Ginger And Membrane Separation Technology Of Ginger Protease

Ginger is one of characteristic resources of our country which has traditional advantages,and it plays an important role in the international market. Chinese ginger is famous by itsexcellent quality and has been planted in the ancient time, but the postpartum processing levelis relatively low. The situation that most of ginger products in the international marketcompetition are raw materials, seriously restricts the development of ginger industry of ourcountry. So the high value-added products are urgent needed to improve the total level ofginger deep processing of our country.This article focused on the simultaneous extraction of gingerol, curcumin and gingerprotease of ginger by using Laiwu Dajiang as materials, reached the optimum conditions byusing single factor test and orthogonal test, got the best extraction scheme, purified gingerprotease on the base of the scheme, determined the ginger protease molecule weight by usingelectrophoresis experiment eventually, column chromatography and membrane separationtechnology was used to purification of ginger protease. The main researching results were asfollowing:(1) Optimization of combined extraction conditionThe ethanol solvent method was used in gingerol, curcumin and ginger proteasesynchronous separation, the optimum combined extraction condition was ginger and ethanolliquid ratio at1:3(w/v), buffer pH at6.5, the ice bathing lasted7h; gingerol, curcumin rotaryevaporation optimum temperature at60℃, the rotating speed at16rpm. Under this condition,the extraction rate of gingerol and curcumin from ginger were3.143‰and3.889‰; gingerprotease was1.376%, specific activity reached4.465×10~6U/g, almost10~0times than thenational standard GB/T23527(5.0×10~4U/g).(2) Determination of molecular weight of ginger proteaseThere were two protein bands in the film after SDS-polyacrylamide gel electrophoresisof protein, a molecular weight was33.3KDa and the other was15.7KDa.(3) Optimum condition of membrane separation of ginger proteasePurifying ultrafiltration was processed under room temperature by polyether sulfonemembrane bag at molecular weights of10~KDa,30KDa and50KDa. The optimum conditionwas that buffer pH at6.98, operating pressure at0.8bar and material liquid ratio at1:4. Theresults showed that the enzyme specific activity mainly exists at33.3KDa and specificactivity was5.369×10~6U/g, which was about10~0times than the national standard GB/T 23527(5.0×10~4U/g). The purifying process also obtained a few of ginger protease at15.7KDawhich the specific activity was6.43×10~3U/g.(4) Column chromatography purification of ginger proteaseThe ginger protease was purified by using Sephadex G-50Medium as filler. Theoptimum condition was16×500mm chromatographic column with10~0mL bed volume (CBV),3mL sample size, elution velocity at1.5mL/min,0.03moL/L phosphate buffer solution whichpH at7.5as elution buffer. Two distinct peaks eluting peaks were gotten, of which peak I hadenzyme activity. The specific activity of the ginger protease was9.97×10~6U/g, andpurification ratio reached3.22times than the vitality (on the basis of the specific activity ofcombined extraction enzyme), and1.86times than membrane separation.