Study On The Extraction And Purification Of Safflower Yellow And Carthamin

Safflower is the dried flower peals of Carthamus tinctorius L, which is one of the traditional affinal drug and diet plant. The main constituent is safflower yellow(SY) along with a small amount of carthamin. The two pigments have been widely used in food and cosmetics industries due to great tinctorial strength and natural colour. Both pigments have good biological activity. The main product of Safflower is safflower yellow which has been widely studied and applicated. There are problems with the production of safflower yellow such as high costs and long production cycle. The abandon of the residue would cause the resources waste. Carthamin was the by-product of safflower yellow, which was less researched or reported. The production type of carthamin are less than safflower yellow, which cannot meet the demand of the market. In this paper, safflower yellow was extracted from Safflower firstly, and then carthamin was extracted from the residue. The study strived to make a comprehensive utilization of safflower, and to find a low costs, green and efficient production processes for the preparation of safflower yellow and carthamin. The main results are as follows:Safflower was crushed and sifted by 40 mesh sieve, with water as the extraction solvent, 70 min as the presoaking time, 14(v/w) as the liquid-solid ratio, 60℃ as the extracting temperature, 50 min as the extracting time, extracted twice. On this condition, the extraction rate of safflower yellow was 97.85%. To remove the impurity of safflower yellow extracts, We added 4%(v/v) chitosan solution, p H 4~5, 20℃ as the flocculating temperature, 1 h as flocculating time. On this condition, the transmittance(T%) of the solution increased by 50% to 84.32±0.6%, and SY retention rate was 92.64±0.41%. The concentration of chitosan and p H of the system significantly affected the Zeta potential of the particles, changing the electrostatic repulsive force; The particles flocculated and were removed from the system due to van der Waals forces and bridging effect.Compared with ZTC clarifying agents, chitosan has higher transmittance and SY retention rate with lower costs. The impurity removal capacity of chitosan was superior to ethanol precipitation method, similar to ultrafiltration, much less than macroporous adsorption resin; Chitosan flocculation process has the maximum SY retention rate. Chitosan flocculation process was easily operated with lower production costs, which can replace ethanol precipitation method and be a green and valid method for the purification of safflower yellow and other natural constituents.The residue above was uesd to extract carthamin to make a comprehensive utilization of Safflower. Took 80% ethanol as the extraction solvent of carthamin, 15(v/w) as the liquid-solid ratio, 45℃ as the extracting temperature, 10 min as the extracting time, extracted twice. On this condition, the relative extraction rate of carthamin was 92.34%. Aqueous two phase system(ATPS) containing(NH4)2SO4 and ethanol was used to purify the carthamin extracts. The concentration of(NH4)2SO4 solution was 0.67 g/m L. The volume ratio between organic and water phase is 2.33(v/v). Ethanol was added to the upper pahse to remove the salt. Carthamin precipitated after ethanol was removed by rotary evaporation. Carthamin was obtained after citric acid-washed twice, centrifugation and freeze-drying. The final product was dark red powder with metallic sheen. The color value was 140.94, which was much higher than commercially available products made by alkali dissolution and acid deposition method. The results of HPLC-MS showed the main component of the sample was quinoid carthamin. Its molecular mass was 910, which was consistent with the literature.The study showed that carthamin has poor thermal stability and resistance. Long illumination time caused the degradation of carthamin. The composition of the application system could cause the decrease of carthamin. The higher the content of water, the faster the carthamin degraded. So the production and storage process of carthamin should be kept in a low teperature and avoide light. In the real application of carthamin, high water content system should be avoided.